Reimplement style values atop NSExpression (#10726)

* [ios, macos] Import headers, not implementation files

* [core] Added accessors for various expression parameters

Added missing parameter accessors to various expression operator classes, as well as a method on InterpolatorBase and Step that enumerates the stops and their values.

* [ios, macos] Silenced warning in test of error condition

* [ios, macos] Made MGLSphericalPosition boxable

* [ios, macos] Implemented array enumeration during conversion

* [ios, macos] Temporarily ignore heatmap layer type

* [ios, macos] Migrated MGLSymbolStyleLayer.text to NSExpression

MGLSymbolStyleLayer.text is now of type NSExpression instead of MGLStyleValue, as a first step toward migrating the entire layer API from style values to expressions.

Implemented conversions from NSExpression to JSON arrays and vice versa. The most common NSExpression functions are now converted into style expressions, but not all of the most common style expression operators are supported yet.

* [ios, macos] Implemented string coercion

* [ios, macos] Color literals

* [ios, macos] Null constant expressions

* [ios, macos] Convert dictionary literals

* [ios, macos] Interpolation expressions

* [ios, macos] to-boolean, to-number, get from object

* [ios, macos] Variable expressions

Implemented custom expression functions for assigning and referring to variables within the context of an expression. Variables are assigned via a “context dictionary” and applied to an subexpression that is given as another argument to the same expression. Also implemented built-in variable expressions for zoom level and heatmap density.

* [ios, macos] Convert colors, offsets, padding in expressions to JSON objects

* [ios, macos] Expression-based style property getters

Implemented a conversion from mbgl::style::PropertyValues to Objective-C JSON objects, which are then converted to NSExpressions.

* [ios, macos] Consolidated property value–expression conversion in MGLStyleValueTransformer

* [ios, macos] Predicate and expression guide

Extracted documentation about predicates from a documentation comment in MGLVectorStyleLayer.h to a new jazzy guide. Added details about NSExpression support as well. Began updating the “For Style Authors” guide to reflect the transition from style values to expressions.

* [ios, macos] Updated style authoring guide

Updated the Information for Style Authors guide to discuss expressions instead of style functions. Included a table mapping style specification expression operators to NSExpression syntaxes.

* [ios, macos] Migrated codegen templates to expressions

* [ios, macos] Applied expression changes via codegen

Ran make darwin-style-code.

* [macos] Migrated macosapp to expressions

* [ios, macos] Updated style function guide

This guide needs to be thoroughly rewritten, but for now the example code has been migrated to expressions.

* [ios, macos] Eviscerated style function tests

* [ios, macos] Updated changelogs

* [ios] Migrated iosapp to expressions

* [ios, macos] Exposed JSON conversion methods publicly

* [ios, macos] Removed MGLStyleValue, MGLStyleFunction

38 files changed, 3304 insertions, 3988 deletions

diff --git a/platform/darwin/src/MGLBackgroundStyleLayer.h b/platform/darwin/src/MGLBackgroundStyleLayer.h
index 659903914c..9d2673c859 100644
--- a/platform/darwin/src/MGLBackgroundStyleLayer.h
+++ b/platform/darwin/src/MGLBackgroundStyleLayer.h
@@ -2,7 +2,6 @@
 // Edit platform/darwin/scripts/generate-style-code.js, then run `make darwin-style-code`.
 
 #import "MGLFoundation.h"
-#import "MGLStyleValue.h"
 #import "MGLStyleLayer.h"
 
 NS_ASSUME_NONNULL_BEGIN
@@ -38,45 +37,28 @@ which it is added.
 
 #pragma mark - Accessing the Paint Attributes
 
-#if TARGET_OS_IPHONE
 /**
  The color with which the background will be drawn.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.blackColor`. Set this property to `nil` to reset it to the default
  value.
  
  This property is only applied to the style if `backgroundPattern` is set to
  `nil`. Otherwise, it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *backgroundColor;
-#else
-/**
- The color with which the background will be drawn.
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.blackColor`. Set this property to `nil` to reset it to the default
- value.
- 
- This property is only applied to the style if `backgroundPattern` is set to
- `nil`. Otherwise, it is ignored.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *backgroundColor;
-#endif
+@property (nonatomic, null_resettable) NSExpression *backgroundColor;
 
 /**
  The transition affecting any changes to this layer’s `backgroundColor` property.
@@ -88,18 +70,21 @@ which it is added.
 /**
  The opacity at which the background will be drawn.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `1`. Set this property to `nil` to reset it to the default value.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *backgroundOpacity;
+@property (nonatomic, null_resettable) NSExpression *backgroundOpacity;
 
 /**
  The transition affecting any changes to this layer’s `backgroundOpacity` property.
@@ -113,13 +98,19 @@ which it is added.
  seamless patterns, image width and height must be a factor of two (2, 4, 8,
  ..., 512).
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant string values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSString *> *backgroundPattern;
+@property (nonatomic, null_resettable) NSExpression *backgroundPattern;
 
 /**
  The transition affecting any changes to this layer’s `backgroundPattern` property.
diff --git a/platform/darwin/src/MGLBackgroundStyleLayer.mm b/platform/darwin/src/MGLBackgroundStyleLayer.mm
index 47b491fc65..7c4cf79709 100644
--- a/platform/darwin/src/MGLBackgroundStyleLayer.mm
+++ b/platform/darwin/src/MGLBackgroundStyleLayer.mm
@@ -32,21 +32,21 @@
 
 #pragma mark - Accessing the Paint Attributes
 
-- (void)setBackgroundColor:(MGLStyleValue<MGLColor *> *)backgroundColor {
+- (void)setBackgroundColor:(NSExpression *)backgroundColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toInterpolatablePropertyValue(backgroundColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::PropertyValue<mbgl::Color>>(backgroundColor);
     self.rawLayer->setBackgroundColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)backgroundColor {
+- (NSExpression *)backgroundColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getBackgroundColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toStyleValue(self.rawLayer->getDefaultBackgroundColor());
+        propertyValue = self.rawLayer->getDefaultBackgroundColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setBackgroundColorTransition:(MGLTransition )transition {
@@ -67,21 +67,21 @@
     return transition;
 }
 
-- (void)setBackgroundOpacity:(MGLStyleValue<NSNumber *> *)backgroundOpacity {
+- (void)setBackgroundOpacity:(NSExpression *)backgroundOpacity {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(backgroundOpacity);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(backgroundOpacity);
     self.rawLayer->setBackgroundOpacity(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)backgroundOpacity {
+- (NSExpression *)backgroundOpacity {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getBackgroundOpacity();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultBackgroundOpacity());
+        propertyValue = self.rawLayer->getDefaultBackgroundOpacity();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setBackgroundOpacityTransition:(MGLTransition )transition {
@@ -102,21 +102,21 @@
     return transition;
 }
 
-- (void)setBackgroundPattern:(MGLStyleValue<NSString *> *)backgroundPattern {
+- (void)setBackgroundPattern:(NSExpression *)backgroundPattern {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::string, NSString *>().toPropertyValue(backgroundPattern);
+    auto mbglValue = MGLStyleValueTransformer<std::string, NSString *>().toPropertyValue<mbgl::style::PropertyValue<std::string>>(backgroundPattern);
     self.rawLayer->setBackgroundPattern(mbglValue);
 }
 
-- (MGLStyleValue<NSString *> *)backgroundPattern {
+- (NSExpression *)backgroundPattern {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getBackgroundPattern();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::string, NSString *>().toStyleValue(self.rawLayer->getDefaultBackgroundPattern());
+        propertyValue = self.rawLayer->getDefaultBackgroundPattern();
     }
-    return MGLStyleValueTransformer<std::string, NSString *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::string, NSString *>().toExpression(propertyValue);
 }
 
 - (void)setBackgroundPatternTransition:(MGLTransition )transition {
diff --git a/platform/darwin/src/MGLCircleStyleLayer.h b/platform/darwin/src/MGLCircleStyleLayer.h
index 86143894b1..caa6d2f6cb 100644
--- a/platform/darwin/src/MGLCircleStyleLayer.h
+++ b/platform/darwin/src/MGLCircleStyleLayer.h
@@ -2,7 +2,6 @@
 // Edit platform/darwin/scripts/generate-style-code.js, then run `make darwin-style-code`.
 
 #import "MGLFoundation.h"
-#import "MGLStyleValue.h"
 #import "MGLVectorStyleLayer.h"
 
 NS_ASSUME_NONNULL_BEGIN
@@ -83,12 +82,11 @@ typedef NS_ENUM(NSUInteger, MGLCircleTranslationAnchor) {
  ```swift
  let layer = MGLCircleStyleLayer(identifier: "circles", source: population)
  layer.sourceLayerIdentifier = "population"
- layer.circleColor = MGLStyleValue(rawValue: .green)
- layer.circleRadius = MGLStyleValue(interpolationMode: .exponential,
-                                    cameraStops: [12: MGLStyleValue(rawValue: 2),
-                                                  22: MGLStyleValue(rawValue: 180)],
-                                    options: [.interpolationBase: 1.75])
- layer.circleOpacity = MGLStyleValue(rawValue: 0.7)
+ layer.circleColor = NSExpression(forConstantValue: UIColor.green)
+ layer.circleRadius = NSExpression(format: "FUNCTION($zoomLevel, 'mgl_interpolateWithCurveType:parameters:stops:', 'exponential', 1.75, %@)",
+                                   [12: 2,
+                                    22: 180])
+ layer.circleOpacity = NSExpression(forConstantValue: 0.7)
  layer.predicate = NSPredicate(format: "%K == %@", "marital-status", "married")
  mapView.style?.addLayer(layer)
  ```
@@ -117,27 +115,19 @@ MGL_EXPORT
  Amount to blur the circle. 1 blurs the circle such that only the centerpoint is
  full opacity.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *circleBlur;
+@property (nonatomic, null_resettable) NSExpression *circleBlur;
 
 /**
  The transition affecting any changes to this layer’s `circleBlur` property.
@@ -146,57 +136,23 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition circleBlurTransition;
 
-#if TARGET_OS_IPHONE
 /**
  The fill color of the circle.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.blackColor`. Set this property to `nil` to reset it to the default
  value.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *circleColor;
-#else
-/**
- The fill color of the circle.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.blackColor`. Set this property to `nil` to reset it to the default
- value.
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *circleColor;
-#endif
+@property (nonatomic, null_resettable) NSExpression *circleColor;
 
 /**
  The transition affecting any changes to this layer’s `circleColor` property.
@@ -208,27 +164,19 @@ MGL_EXPORT
 /**
  The opacity at which the circle will be drawn.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1`. Set this property to `nil` to reset
- it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to the float
+ `1`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *circleOpacity;
+@property (nonatomic, null_resettable) NSExpression *circleOpacity;
 
 /**
  The transition affecting any changes to this layer’s `circleOpacity` property.
@@ -240,44 +188,44 @@ MGL_EXPORT
 /**
  Orientation of circle when map is pitched.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLCirclePitchAlignmentViewport`. Set this
- property to `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to
+ `viewport`. Set this property to `nil` to reset it to the default value.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ * Constant `MGLCirclePitchAlignment` values
+ * Any of the following constant string values:
+   * `map`: The circle is aligned to the plane of the map.
+   * `viewport`: The circle is aligned to the plane of the viewport.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *circlePitchAlignment;
+@property (nonatomic, null_resettable) NSExpression *circlePitchAlignment;
 
 /**
  Circle radius.
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `5`. Set this property to `nil` to reset
- it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to the float
+ `5`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *circleRadius;
+@property (nonatomic, null_resettable) NSExpression *circleRadius;
 
 /**
  The transition affecting any changes to this layer’s `circleRadius` property.
@@ -289,75 +237,50 @@ MGL_EXPORT
 /**
  Controls the scaling behavior of the circle when the map is pitched.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLCircleScaleAlignmentMap`. Set this property to
- `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `map`.
+ Set this property to `nil` to reset it to the default value.
  
  This attribute corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-circle-pitch-scale"><code>circle-pitch-scale</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLCircleScaleAlignment` values
+ * Any of the following constant string values:
+   * `map`: Circles are scaled according to their apparent distance to the
+ camera.
+   * `viewport`: Circles are not scaled.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *circleScaleAlignment;
+@property (nonatomic, null_resettable) NSExpression *circleScaleAlignment;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *circlePitchScale __attribute__((unavailable("Use circleScaleAlignment instead.")));
+@property (nonatomic, null_resettable) NSExpression *circlePitchScale __attribute__((unavailable("Use circleScaleAlignment instead.")));
 
-#if TARGET_OS_IPHONE
 /**
  The stroke color of the circle.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.blackColor`. Set this property to `nil` to reset it to the default
  value.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *circleStrokeColor;
-#else
-/**
- The stroke color of the circle.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.blackColor`. Set this property to `nil` to reset it to the default
- value.
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *circleStrokeColor;
-#endif
+@property (nonatomic, null_resettable) NSExpression *circleStrokeColor;
 
 /**
  The transition affecting any changes to this layer’s `circleStrokeColor` property.
@@ -369,27 +292,19 @@ MGL_EXPORT
 /**
  The opacity of the circle's stroke.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1`. Set this property to `nil` to reset
- it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to the float
+ `1`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *circleStrokeOpacity;
+@property (nonatomic, null_resettable) NSExpression *circleStrokeOpacity;
 
 /**
  The transition affecting any changes to this layer’s `circleStrokeOpacity` property.
@@ -404,27 +319,19 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *circleStrokeWidth;
+@property (nonatomic, null_resettable) NSExpression *circleStrokeWidth;
 
 /**
  The transition affecting any changes to this layer’s `circleStrokeWidth` property.
@@ -439,7 +346,7 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 points rightward and 0
  points downward. Set this property to `nil` to reset it to the default value.
  
@@ -447,21 +354,25 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-circle-translate"><code>circle-translate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *circleTranslation;
+@property (nonatomic, null_resettable) NSExpression *circleTranslation;
 #else
 /**
  The geometry's offset.
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 points rightward and 0
  points upward. Set this property to `nil` to reset it to the default value.
  
@@ -469,14 +380,18 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-circle-translate"><code>circle-translate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *circleTranslation;
+@property (nonatomic, null_resettable) NSExpression *circleTranslation;
 #endif
 
 /**
@@ -486,14 +401,13 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition circleTranslationTransition;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *circleTranslate __attribute__((unavailable("Use circleTranslation instead.")));
+@property (nonatomic, null_resettable) NSExpression *circleTranslate __attribute__((unavailable("Use circleTranslation instead.")));
 
 /**
  Controls the frame of reference for `circleTranslation`.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLCircleTranslationAnchorMap`. Set this property
- to `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `map`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `circleTranslation` is non-`nil`.
  Otherwise, it is ignored.
@@ -502,15 +416,24 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-circle-translate-anchor"><code>circle-translate-anchor</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLCircleTranslationAnchor` values
+ * Any of the following constant string values:
+   * `map`: The circle is translated relative to the map.
+   * `viewport`: The circle is translated relative to the viewport.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *circleTranslationAnchor;
+@property (nonatomic, null_resettable) NSExpression *circleTranslationAnchor;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *circleTranslateAnchor __attribute__((unavailable("Use circleTranslationAnchor instead.")));
+@property (nonatomic, null_resettable) NSExpression *circleTranslateAnchor __attribute__((unavailable("Use circleTranslationAnchor instead.")));
 
 @end
 
diff --git a/platform/darwin/src/MGLCircleStyleLayer.mm b/platform/darwin/src/MGLCircleStyleLayer.mm
index 71ae37035e..0be3920987 100644
--- a/platform/darwin/src/MGLCircleStyleLayer.mm
+++ b/platform/darwin/src/MGLCircleStyleLayer.mm
@@ -87,21 +87,21 @@ namespace mbgl {
 
 #pragma mark - Accessing the Paint Attributes
 
-- (void)setCircleBlur:(MGLStyleValue<NSNumber *> *)circleBlur {
+- (void)setCircleBlur:(NSExpression *)circleBlur {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(circleBlur);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(circleBlur);
     self.rawLayer->setCircleBlur(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)circleBlur {
+- (NSExpression *)circleBlur {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getCircleBlur();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultCircleBlur());
+        propertyValue = self.rawLayer->getDefaultCircleBlur();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setCircleBlurTransition:(MGLTransition )transition {
@@ -122,21 +122,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setCircleColor:(MGLStyleValue<MGLColor *> *)circleColor {
+- (void)setCircleColor:(NSExpression *)circleColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenPropertyValue(circleColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::Color>>(circleColor);
     self.rawLayer->setCircleColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)circleColor {
+- (NSExpression *)circleColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getCircleColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(self.rawLayer->getDefaultCircleColor());
+        propertyValue = self.rawLayer->getDefaultCircleColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setCircleColorTransition:(MGLTransition )transition {
@@ -157,21 +157,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setCircleOpacity:(MGLStyleValue<NSNumber *> *)circleOpacity {
+- (void)setCircleOpacity:(NSExpression *)circleOpacity {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(circleOpacity);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(circleOpacity);
     self.rawLayer->setCircleOpacity(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)circleOpacity {
+- (NSExpression *)circleOpacity {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getCircleOpacity();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultCircleOpacity());
+        propertyValue = self.rawLayer->getDefaultCircleOpacity();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setCircleOpacityTransition:(MGLTransition )transition {
@@ -192,38 +192,38 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setCirclePitchAlignment:(MGLStyleValue<NSValue *> *)circlePitchAlignment {
+- (void)setCirclePitchAlignment:(NSExpression *)circlePitchAlignment {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLCirclePitchAlignment>().toEnumPropertyValue(circlePitchAlignment);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLCirclePitchAlignment>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::AlignmentType>>(circlePitchAlignment);
     self.rawLayer->setCirclePitchAlignment(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)circlePitchAlignment {
+- (NSExpression *)circlePitchAlignment {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getCirclePitchAlignment();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLCirclePitchAlignment>().toEnumStyleValue(self.rawLayer->getDefaultCirclePitchAlignment());
+        propertyValue = self.rawLayer->getDefaultCirclePitchAlignment();
     }
-    return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLCirclePitchAlignment>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLCirclePitchAlignment>().toExpression(propertyValue);
 }
 
-- (void)setCircleRadius:(MGLStyleValue<NSNumber *> *)circleRadius {
+- (void)setCircleRadius:(NSExpression *)circleRadius {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(circleRadius);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(circleRadius);
     self.rawLayer->setCircleRadius(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)circleRadius {
+- (NSExpression *)circleRadius {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getCircleRadius();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultCircleRadius());
+        propertyValue = self.rawLayer->getDefaultCircleRadius();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setCircleRadiusTransition:(MGLTransition )transition {
@@ -244,45 +244,45 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setCircleScaleAlignment:(MGLStyleValue<NSValue *> *)circleScaleAlignment {
+- (void)setCircleScaleAlignment:(NSExpression *)circleScaleAlignment {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::CirclePitchScaleType, NSValue *, mbgl::style::CirclePitchScaleType, MGLCircleScaleAlignment>().toEnumPropertyValue(circleScaleAlignment);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::CirclePitchScaleType, NSValue *, mbgl::style::CirclePitchScaleType, MGLCircleScaleAlignment>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::CirclePitchScaleType>>(circleScaleAlignment);
     self.rawLayer->setCirclePitchScale(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)circleScaleAlignment {
+- (NSExpression *)circleScaleAlignment {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getCirclePitchScale();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::CirclePitchScaleType, NSValue *, mbgl::style::CirclePitchScaleType, MGLCircleScaleAlignment>().toEnumStyleValue(self.rawLayer->getDefaultCirclePitchScale());
+        propertyValue = self.rawLayer->getDefaultCirclePitchScale();
     }
-    return MGLStyleValueTransformer<mbgl::style::CirclePitchScaleType, NSValue *, mbgl::style::CirclePitchScaleType, MGLCircleScaleAlignment>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::CirclePitchScaleType, NSValue *, mbgl::style::CirclePitchScaleType, MGLCircleScaleAlignment>().toExpression(propertyValue);
 }
 
-- (void)setCirclePitchScale:(MGLStyleValue<NSValue *> *)circlePitchScale {
+- (void)setCirclePitchScale:(NSExpression *)circlePitchScale {
 }
 
-- (MGLStyleValue<NSValue *> *)circlePitchScale {
+- (NSExpression *)circlePitchScale {
     return self.circleScaleAlignment;
 }
 
-- (void)setCircleStrokeColor:(MGLStyleValue<MGLColor *> *)circleStrokeColor {
+- (void)setCircleStrokeColor:(NSExpression *)circleStrokeColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenPropertyValue(circleStrokeColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::Color>>(circleStrokeColor);
     self.rawLayer->setCircleStrokeColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)circleStrokeColor {
+- (NSExpression *)circleStrokeColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getCircleStrokeColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(self.rawLayer->getDefaultCircleStrokeColor());
+        propertyValue = self.rawLayer->getDefaultCircleStrokeColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setCircleStrokeColorTransition:(MGLTransition )transition {
@@ -303,21 +303,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setCircleStrokeOpacity:(MGLStyleValue<NSNumber *> *)circleStrokeOpacity {
+- (void)setCircleStrokeOpacity:(NSExpression *)circleStrokeOpacity {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(circleStrokeOpacity);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(circleStrokeOpacity);
     self.rawLayer->setCircleStrokeOpacity(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)circleStrokeOpacity {
+- (NSExpression *)circleStrokeOpacity {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getCircleStrokeOpacity();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultCircleStrokeOpacity());
+        propertyValue = self.rawLayer->getDefaultCircleStrokeOpacity();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setCircleStrokeOpacityTransition:(MGLTransition )transition {
@@ -338,21 +338,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setCircleStrokeWidth:(MGLStyleValue<NSNumber *> *)circleStrokeWidth {
+- (void)setCircleStrokeWidth:(NSExpression *)circleStrokeWidth {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(circleStrokeWidth);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(circleStrokeWidth);
     self.rawLayer->setCircleStrokeWidth(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)circleStrokeWidth {
+- (NSExpression *)circleStrokeWidth {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getCircleStrokeWidth();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultCircleStrokeWidth());
+        propertyValue = self.rawLayer->getDefaultCircleStrokeWidth();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setCircleStrokeWidthTransition:(MGLTransition )transition {
@@ -373,21 +373,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setCircleTranslation:(MGLStyleValue<NSValue *> *)circleTranslation {
+- (void)setCircleTranslation:(NSExpression *)circleTranslation {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toInterpolatablePropertyValue(circleTranslation);
+    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toPropertyValue<mbgl::style::PropertyValue<std::array<float, 2>>>(circleTranslation);
     self.rawLayer->setCircleTranslate(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)circleTranslation {
+- (NSExpression *)circleTranslation {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getCircleTranslate();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toStyleValue(self.rawLayer->getDefaultCircleTranslate());
+        propertyValue = self.rawLayer->getDefaultCircleTranslate();
     }
-    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toExpression(propertyValue);
 }
 
 - (void)setCircleTranslationTransition:(MGLTransition )transition {
@@ -408,34 +408,34 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setCircleTranslate:(MGLStyleValue<NSValue *> *)circleTranslate {
+- (void)setCircleTranslate:(NSExpression *)circleTranslate {
 }
 
-- (MGLStyleValue<NSValue *> *)circleTranslate {
+- (NSExpression *)circleTranslate {
     return self.circleTranslation;
 }
 
-- (void)setCircleTranslationAnchor:(MGLStyleValue<NSValue *> *)circleTranslationAnchor {
+- (void)setCircleTranslationAnchor:(NSExpression *)circleTranslationAnchor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLCircleTranslationAnchor>().toEnumPropertyValue(circleTranslationAnchor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLCircleTranslationAnchor>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::TranslateAnchorType>>(circleTranslationAnchor);
     self.rawLayer->setCircleTranslateAnchor(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)circleTranslationAnchor {
+- (NSExpression *)circleTranslationAnchor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getCircleTranslateAnchor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLCircleTranslationAnchor>().toEnumStyleValue(self.rawLayer->getDefaultCircleTranslateAnchor());
+        propertyValue = self.rawLayer->getDefaultCircleTranslateAnchor();
     }
-    return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLCircleTranslationAnchor>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLCircleTranslationAnchor>().toExpression(propertyValue);
 }
 
-- (void)setCircleTranslateAnchor:(MGLStyleValue<NSValue *> *)circleTranslateAnchor {
+- (void)setCircleTranslateAnchor:(NSExpression *)circleTranslateAnchor {
 }
 
-- (MGLStyleValue<NSValue *> *)circleTranslateAnchor {
+- (NSExpression *)circleTranslateAnchor {
     return self.circleTranslationAnchor;
 }
 
diff --git a/platform/darwin/src/MGLConversion.h b/platform/darwin/src/MGLConversion.h
index 0d18d4e716..92a6720e6a 100644
--- a/platform/darwin/src/MGLConversion.h
+++ b/platform/darwin/src/MGLConversion.h
@@ -62,10 +62,14 @@ public:
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wnullability-completeness"
     template <class Fn>
-    static optional<Error> eachMember(const Holder&, Fn&&) {
+    static optional<Error> eachMember(const Holder& holder, Fn&& visit) {
 #pragma clang diagnostic pop
-        // Not implemented (unneeded for MGLStyleFunction conversion).
-        NSCAssert(NO, @"eachMember not implemented");
+        [holder.value enumerateKeysAndObjectsUsingBlock:^(id  _Nonnull key, id  _Nonnull obj, BOOL * _Nonnull stop) {
+            auto result = visit(std::string(static_cast<const char *>([key UTF8String])), obj);
+            if (result) {
+                *stop = YES;
+            }
+        }];
         return {};
     }
 
diff --git a/platform/darwin/src/MGLFeature.mm b/platform/darwin/src/MGLFeature.mm
index 033052bda8..ee2c71be21 100644
--- a/platform/darwin/src/MGLFeature.mm
+++ b/platform/darwin/src/MGLFeature.mm
@@ -12,7 +12,7 @@
 
 #import "NSDictionary+MGLAdditions.h"
 #import "NSArray+MGLAdditions.h"
-#import "NSExpression+MGLAdditions.h"
+#import "NSExpression+MGLPrivateAdditions.h"
 
 #import <mbgl/util/geometry.hpp>
 #import <mbgl/style/conversion/geojson.hpp>
diff --git a/platform/darwin/src/MGLFillExtrusionStyleLayer.h b/platform/darwin/src/MGLFillExtrusionStyleLayer.h
index 02d6b2ff88..d1d5af6ba2 100644
--- a/platform/darwin/src/MGLFillExtrusionStyleLayer.h
+++ b/platform/darwin/src/MGLFillExtrusionStyleLayer.h
@@ -2,7 +2,6 @@
 // Edit platform/darwin/scripts/generate-style-code.js, then run `make darwin-style-code`.
 
 #import "MGLFoundation.h"
-#import "MGLStyleValue.h"
 #import "MGLVectorStyleLayer.h"
 
 NS_ASSUME_NONNULL_BEGIN
@@ -45,8 +44,8 @@ typedef NS_ENUM(NSUInteger, MGLFillExtrusionTranslationAnchor) {
  ```swift
  let layer = MGLFillExtrusionStyleLayer(identifier: "buildings", source: buildings)
  layer.sourceLayerIdentifier = "building"
- layer.fillExtrusionHeight = MGLStyleValue(interpolationMode: .identity, sourceStops: nil, attributeName: "height", options: nil)
- layer.fillExtrusionBase = MGLStyleValue(interpolationMode: .identity, sourceStops: nil, attributeName: "min_height", options: nil)
+ layer.fillExtrusionHeight = NSExpression(forKeyPath: "height")
+ layer.fillExtrusionBase = NSExpression(forKeyPath: "min_height")
  layer.predicate = NSPredicate(format: "extrude == 'true'")
  mapView.style?.addLayer(layer)
  ```
@@ -77,30 +76,22 @@ MGL_EXPORT
  
  This property is measured in meters.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `fillExtrusionHeight` is
  non-`nil`. Otherwise, it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *fillExtrusionBase;
+@property (nonatomic, null_resettable) NSExpression *fillExtrusionBase;
 
 /**
  The transition affecting any changes to this layer’s `fillExtrusionBase` property.
@@ -109,69 +100,29 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition fillExtrusionBaseTransition;
 
-#if TARGET_OS_IPHONE
 /**
  The base color of this layer. The extrusion's surfaces will be shaded
  differently based on this color in combination with the `light` settings. If
  this color is specified with an alpha component, the alpha component will be
  ignored; use `fillExtrusionOpacity` to set layer opacityco.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.blackColor`. Set this property to `nil` to reset it to the default
  value.
  
  This property is only applied to the style if `fillExtrusionPattern` is set to
  `nil`. Otherwise, it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *fillExtrusionColor;
-#else
-/**
- The base color of this layer. The extrusion's surfaces will be shaded
- differently based on this color in combination with the `light` settings. If
- this color is specified with an alpha component, the alpha component will be
- ignored; use `fillExtrusionOpacity` to set layer opacityco.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.blackColor`. Set this property to `nil` to reset it to the default
- value.
- 
- This property is only applied to the style if `fillExtrusionPattern` is set to
- `nil`. Otherwise, it is ignored.
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *fillExtrusionColor;
-#endif
+@property (nonatomic, null_resettable) NSExpression *fillExtrusionColor;
 
 /**
  The transition affecting any changes to this layer’s `fillExtrusionColor` property.
@@ -185,27 +136,19 @@ MGL_EXPORT
  
  This property is measured in meters.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *fillExtrusionHeight;
+@property (nonatomic, null_resettable) NSExpression *fillExtrusionHeight;
 
 /**
  The transition affecting any changes to this layer’s `fillExtrusionHeight` property.
@@ -218,18 +161,21 @@ MGL_EXPORT
  The opacity of the entire fill extrusion layer. This is rendered on a
  per-layer, not per-feature, basis, and data-driven styling is not available.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `1`. Set this property to `nil` to reset it to the default value.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *fillExtrusionOpacity;
+@property (nonatomic, null_resettable) NSExpression *fillExtrusionOpacity;
 
 /**
  The transition affecting any changes to this layer’s `fillExtrusionOpacity` property.
@@ -243,13 +189,19 @@ MGL_EXPORT
  seamless patterns, image width and height must be a factor of two (2, 4, 8,
  ..., 512).
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant string values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSString *> *fillExtrusionPattern;
+@property (nonatomic, null_resettable) NSExpression *fillExtrusionPattern;
 
 /**
  The transition affecting any changes to this layer’s `fillExtrusionPattern` property.
@@ -264,7 +216,7 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 points rightward and 0
  points downward. Set this property to `nil` to reset it to the default value.
  
@@ -272,21 +224,25 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-fill-extrusion-translate"><code>fill-extrusion-translate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *fillExtrusionTranslation;
+@property (nonatomic, null_resettable) NSExpression *fillExtrusionTranslation;
 #else
 /**
  The geometry's offset.
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 points rightward and 0
  points upward. Set this property to `nil` to reset it to the default value.
  
@@ -294,14 +250,18 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-fill-extrusion-translate"><code>fill-extrusion-translate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *fillExtrusionTranslation;
+@property (nonatomic, null_resettable) NSExpression *fillExtrusionTranslation;
 #endif
 
 /**
@@ -311,14 +271,13 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition fillExtrusionTranslationTransition;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *fillExtrusionTranslate __attribute__((unavailable("Use fillExtrusionTranslation instead.")));
+@property (nonatomic, null_resettable) NSExpression *fillExtrusionTranslate __attribute__((unavailable("Use fillExtrusionTranslation instead.")));
 
 /**
  Controls the frame of reference for `fillExtrusionTranslation`.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLFillExtrusionTranslationAnchorMap`. Set this
- property to `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `map`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `fillExtrusionTranslation` is
  non-`nil`. Otherwise, it is ignored.
@@ -327,15 +286,24 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-fill-extrusion-translate-anchor"><code>fill-extrusion-translate-anchor</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLFillExtrusionTranslationAnchor` values
+ * Any of the following constant string values:
+   * `map`: The fill extrusion is translated relative to the map.
+   * `viewport`: The fill extrusion is translated relative to the viewport.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *fillExtrusionTranslationAnchor;
+@property (nonatomic, null_resettable) NSExpression *fillExtrusionTranslationAnchor;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *fillExtrusionTranslateAnchor __attribute__((unavailable("Use fillExtrusionTranslationAnchor instead.")));
+@property (nonatomic, null_resettable) NSExpression *fillExtrusionTranslateAnchor __attribute__((unavailable("Use fillExtrusionTranslationAnchor instead.")));
 
 @end
 
diff --git a/platform/darwin/src/MGLFillExtrusionStyleLayer.mm b/platform/darwin/src/MGLFillExtrusionStyleLayer.mm
index b00ed8e09f..1baa264689 100644
--- a/platform/darwin/src/MGLFillExtrusionStyleLayer.mm
+++ b/platform/darwin/src/MGLFillExtrusionStyleLayer.mm
@@ -77,21 +77,21 @@ namespace mbgl {
 
 #pragma mark - Accessing the Paint Attributes
 
-- (void)setFillExtrusionBase:(MGLStyleValue<NSNumber *> *)fillExtrusionBase {
+- (void)setFillExtrusionBase:(NSExpression *)fillExtrusionBase {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(fillExtrusionBase);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(fillExtrusionBase);
     self.rawLayer->setFillExtrusionBase(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)fillExtrusionBase {
+- (NSExpression *)fillExtrusionBase {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillExtrusionBase();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultFillExtrusionBase());
+        propertyValue = self.rawLayer->getDefaultFillExtrusionBase();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setFillExtrusionBaseTransition:(MGLTransition )transition {
@@ -112,21 +112,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setFillExtrusionColor:(MGLStyleValue<MGLColor *> *)fillExtrusionColor {
+- (void)setFillExtrusionColor:(NSExpression *)fillExtrusionColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenPropertyValue(fillExtrusionColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::Color>>(fillExtrusionColor);
     self.rawLayer->setFillExtrusionColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)fillExtrusionColor {
+- (NSExpression *)fillExtrusionColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillExtrusionColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(self.rawLayer->getDefaultFillExtrusionColor());
+        propertyValue = self.rawLayer->getDefaultFillExtrusionColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setFillExtrusionColorTransition:(MGLTransition )transition {
@@ -147,21 +147,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setFillExtrusionHeight:(MGLStyleValue<NSNumber *> *)fillExtrusionHeight {
+- (void)setFillExtrusionHeight:(NSExpression *)fillExtrusionHeight {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(fillExtrusionHeight);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(fillExtrusionHeight);
     self.rawLayer->setFillExtrusionHeight(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)fillExtrusionHeight {
+- (NSExpression *)fillExtrusionHeight {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillExtrusionHeight();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultFillExtrusionHeight());
+        propertyValue = self.rawLayer->getDefaultFillExtrusionHeight();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setFillExtrusionHeightTransition:(MGLTransition )transition {
@@ -182,21 +182,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setFillExtrusionOpacity:(MGLStyleValue<NSNumber *> *)fillExtrusionOpacity {
+- (void)setFillExtrusionOpacity:(NSExpression *)fillExtrusionOpacity {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(fillExtrusionOpacity);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(fillExtrusionOpacity);
     self.rawLayer->setFillExtrusionOpacity(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)fillExtrusionOpacity {
+- (NSExpression *)fillExtrusionOpacity {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillExtrusionOpacity();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultFillExtrusionOpacity());
+        propertyValue = self.rawLayer->getDefaultFillExtrusionOpacity();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setFillExtrusionOpacityTransition:(MGLTransition )transition {
@@ -217,21 +217,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setFillExtrusionPattern:(MGLStyleValue<NSString *> *)fillExtrusionPattern {
+- (void)setFillExtrusionPattern:(NSExpression *)fillExtrusionPattern {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::string, NSString *>().toPropertyValue(fillExtrusionPattern);
+    auto mbglValue = MGLStyleValueTransformer<std::string, NSString *>().toPropertyValue<mbgl::style::PropertyValue<std::string>>(fillExtrusionPattern);
     self.rawLayer->setFillExtrusionPattern(mbglValue);
 }
 
-- (MGLStyleValue<NSString *> *)fillExtrusionPattern {
+- (NSExpression *)fillExtrusionPattern {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillExtrusionPattern();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::string, NSString *>().toStyleValue(self.rawLayer->getDefaultFillExtrusionPattern());
+        propertyValue = self.rawLayer->getDefaultFillExtrusionPattern();
     }
-    return MGLStyleValueTransformer<std::string, NSString *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::string, NSString *>().toExpression(propertyValue);
 }
 
 - (void)setFillExtrusionPatternTransition:(MGLTransition )transition {
@@ -252,21 +252,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setFillExtrusionTranslation:(MGLStyleValue<NSValue *> *)fillExtrusionTranslation {
+- (void)setFillExtrusionTranslation:(NSExpression *)fillExtrusionTranslation {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toInterpolatablePropertyValue(fillExtrusionTranslation);
+    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toPropertyValue<mbgl::style::PropertyValue<std::array<float, 2>>>(fillExtrusionTranslation);
     self.rawLayer->setFillExtrusionTranslate(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)fillExtrusionTranslation {
+- (NSExpression *)fillExtrusionTranslation {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillExtrusionTranslate();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toStyleValue(self.rawLayer->getDefaultFillExtrusionTranslate());
+        propertyValue = self.rawLayer->getDefaultFillExtrusionTranslate();
     }
-    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toExpression(propertyValue);
 }
 
 - (void)setFillExtrusionTranslationTransition:(MGLTransition )transition {
@@ -287,34 +287,34 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setFillExtrusionTranslate:(MGLStyleValue<NSValue *> *)fillExtrusionTranslate {
+- (void)setFillExtrusionTranslate:(NSExpression *)fillExtrusionTranslate {
 }
 
-- (MGLStyleValue<NSValue *> *)fillExtrusionTranslate {
+- (NSExpression *)fillExtrusionTranslate {
     return self.fillExtrusionTranslation;
 }
 
-- (void)setFillExtrusionTranslationAnchor:(MGLStyleValue<NSValue *> *)fillExtrusionTranslationAnchor {
+- (void)setFillExtrusionTranslationAnchor:(NSExpression *)fillExtrusionTranslationAnchor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLFillExtrusionTranslationAnchor>().toEnumPropertyValue(fillExtrusionTranslationAnchor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLFillExtrusionTranslationAnchor>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::TranslateAnchorType>>(fillExtrusionTranslationAnchor);
     self.rawLayer->setFillExtrusionTranslateAnchor(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)fillExtrusionTranslationAnchor {
+- (NSExpression *)fillExtrusionTranslationAnchor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillExtrusionTranslateAnchor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLFillExtrusionTranslationAnchor>().toEnumStyleValue(self.rawLayer->getDefaultFillExtrusionTranslateAnchor());
+        propertyValue = self.rawLayer->getDefaultFillExtrusionTranslateAnchor();
     }
-    return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLFillExtrusionTranslationAnchor>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLFillExtrusionTranslationAnchor>().toExpression(propertyValue);
 }
 
-- (void)setFillExtrusionTranslateAnchor:(MGLStyleValue<NSValue *> *)fillExtrusionTranslateAnchor {
+- (void)setFillExtrusionTranslateAnchor:(NSExpression *)fillExtrusionTranslateAnchor {
 }
 
-- (MGLStyleValue<NSValue *> *)fillExtrusionTranslateAnchor {
+- (NSExpression *)fillExtrusionTranslateAnchor {
     return self.fillExtrusionTranslationAnchor;
 }
 
diff --git a/platform/darwin/src/MGLFillStyleLayer.h b/platform/darwin/src/MGLFillStyleLayer.h
index e385256aae..5caab91b45 100644
--- a/platform/darwin/src/MGLFillStyleLayer.h
+++ b/platform/darwin/src/MGLFillStyleLayer.h
@@ -2,7 +2,6 @@
 // Edit platform/darwin/scripts/generate-style-code.js, then run `make darwin-style-code`.
 
 #import "MGLFoundation.h"
-#import "MGLStyleValue.h"
 #import "MGLVectorStyleLayer.h"
 
 NS_ASSUME_NONNULL_BEGIN
@@ -44,7 +43,7 @@ typedef NS_ENUM(NSUInteger, MGLFillTranslationAnchor) {
  ```swift
  let layer = MGLFillStyleLayer(identifier: "parks", source: parks)
  layer.sourceLayerIdentifier = "parks"
- layer.fillColor = MGLStyleValue(rawValue: .green)
+ layer.fillColor = NSExpression(forConstantValue: UIColor.green)
  layer.predicate = NSPredicate(format: "type == %@", "national-park")
  mapView.style?.addLayer(layer)
  ```
@@ -72,81 +71,49 @@ MGL_EXPORT
 /**
  Whether or not the fill should be antialiased.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing `YES`. Set this property to `nil` to reset it to
- the default value.
+ The default value of this property is an expression that evaluates to `YES`.
+ Set this property to `nil` to reset it to the default value.
  
  This attribute corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-fill-antialias"><code>fill-antialias</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ * Constant Boolean values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable, getter=isFillAntialiased) MGLStyleValue<NSNumber *> *fillAntialiased;
+@property (nonatomic, null_resettable, getter=isFillAntialiased) NSExpression *fillAntialiased;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *fillAntialias __attribute__((unavailable("Use fillAntialiased instead.")));
+@property (nonatomic, null_resettable) NSExpression *fillAntialias __attribute__((unavailable("Use fillAntialiased instead.")));
 
-#if TARGET_OS_IPHONE
 /**
  The color of the filled part of this layer.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.blackColor`. Set this property to `nil` to reset it to the default
  value.
  
  This property is only applied to the style if `fillPattern` is set to `nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *fillColor;
-#else
-/**
- The color of the filled part of this layer.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.blackColor`. Set this property to `nil` to reset it to the default
- value.
- 
- This property is only applied to the style if `fillPattern` is set to `nil`.
- Otherwise, it is ignored.
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *fillColor;
-#endif
+@property (nonatomic, null_resettable) NSExpression *fillColor;
 
 /**
  The transition affecting any changes to this layer’s `fillColor` property.
@@ -159,27 +126,19 @@ MGL_EXPORT
  The opacity of the entire fill layer. In contrast to the `fillColor`, this
  value will also affect the 1pt stroke around the fill, if the stroke is used.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1`. Set this property to `nil` to reset
- it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to the float
+ `1`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *fillOpacity;
+@property (nonatomic, null_resettable) NSExpression *fillOpacity;
 
 /**
  The transition affecting any changes to this layer’s `fillOpacity` property.
@@ -188,57 +147,23 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition fillOpacityTransition;
 
-#if TARGET_OS_IPHONE
 /**
  The outline color of the fill. Matches the value of `fillColor` if unspecified.
  
  This property is only applied to the style if `fillPattern` is set to `nil`,
- and `fillAntialiased` is set to an `MGLStyleValue` object containing an
- `NSNumber` object containing `YES`. Otherwise, it is ignored.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *fillOutlineColor;
-#else
-/**
- The outline color of the fill. Matches the value of `fillColor` if unspecified.
+ and `fillAntialiased` is set to an expression that evaluates to `YES`.
+ Otherwise, it is ignored.
  
- This property is only applied to the style if `fillPattern` is set to `nil`,
- and `fillAntialiased` is set to an `MGLStyleValue` object containing an
- `NSNumber` object containing `YES`. Otherwise, it is ignored.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *fillOutlineColor;
-#endif
+@property (nonatomic, null_resettable) NSExpression *fillOutlineColor;
 
 /**
  The transition affecting any changes to this layer’s `fillOutlineColor` property.
@@ -251,13 +176,19 @@ MGL_EXPORT
  Name of image in sprite to use for drawing image fills. For seamless patterns,
  image width and height must be a factor of two (2, 4, 8, ..., 512).
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant string values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSString *> *fillPattern;
+@property (nonatomic, null_resettable) NSExpression *fillPattern;
 
 /**
  The transition affecting any changes to this layer’s `fillPattern` property.
@@ -272,7 +203,7 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 points rightward and 0
  points downward. Set this property to `nil` to reset it to the default value.
  
@@ -280,21 +211,25 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-fill-translate"><code>fill-translate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *fillTranslation;
+@property (nonatomic, null_resettable) NSExpression *fillTranslation;
 #else
 /**
  The geometry's offset.
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 points rightward and 0
  points upward. Set this property to `nil` to reset it to the default value.
  
@@ -302,14 +237,18 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-fill-translate"><code>fill-translate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *fillTranslation;
+@property (nonatomic, null_resettable) NSExpression *fillTranslation;
 #endif
 
 /**
@@ -319,14 +258,13 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition fillTranslationTransition;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *fillTranslate __attribute__((unavailable("Use fillTranslation instead.")));
+@property (nonatomic, null_resettable) NSExpression *fillTranslate __attribute__((unavailable("Use fillTranslation instead.")));
 
 /**
  Controls the frame of reference for `fillTranslation`.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLFillTranslationAnchorMap`. Set this property to
- `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `map`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `fillTranslation` is non-`nil`.
  Otherwise, it is ignored.
@@ -335,15 +273,24 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-fill-translate-anchor"><code>fill-translate-anchor</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLFillTranslationAnchor` values
+ * Any of the following constant string values:
+   * `map`: The fill is translated relative to the map.
+   * `viewport`: The fill is translated relative to the viewport.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *fillTranslationAnchor;
+@property (nonatomic, null_resettable) NSExpression *fillTranslationAnchor;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *fillTranslateAnchor __attribute__((unavailable("Use fillTranslationAnchor instead.")));
+@property (nonatomic, null_resettable) NSExpression *fillTranslateAnchor __attribute__((unavailable("Use fillTranslationAnchor instead.")));
 
 @end
 
diff --git a/platform/darwin/src/MGLFillStyleLayer.mm b/platform/darwin/src/MGLFillStyleLayer.mm
index 71b01a6661..ab28b414b5 100644
--- a/platform/darwin/src/MGLFillStyleLayer.mm
+++ b/platform/darwin/src/MGLFillStyleLayer.mm
@@ -77,45 +77,45 @@ namespace mbgl {
 
 #pragma mark - Accessing the Paint Attributes
 
-- (void)setFillAntialiased:(MGLStyleValue<NSNumber *> *)fillAntialiased {
+- (void)setFillAntialiased:(NSExpression *)fillAntialiased {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue(fillAntialiased);
+    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<bool>>(fillAntialiased);
     self.rawLayer->setFillAntialias(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)isFillAntialiased {
+- (NSExpression *)isFillAntialiased {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillAntialias();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(self.rawLayer->getDefaultFillAntialias());
+        propertyValue = self.rawLayer->getDefaultFillAntialias();
     }
-    return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<bool, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setFillAntialias:(MGLStyleValue<NSNumber *> *)fillAntialias {
+- (void)setFillAntialias:(NSExpression *)fillAntialias {
 }
 
-- (MGLStyleValue<NSNumber *> *)fillAntialias {
+- (NSExpression *)fillAntialias {
     return self.isFillAntialiased;
 }
 
-- (void)setFillColor:(MGLStyleValue<MGLColor *> *)fillColor {
+- (void)setFillColor:(NSExpression *)fillColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenPropertyValue(fillColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::Color>>(fillColor);
     self.rawLayer->setFillColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)fillColor {
+- (NSExpression *)fillColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(self.rawLayer->getDefaultFillColor());
+        propertyValue = self.rawLayer->getDefaultFillColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setFillColorTransition:(MGLTransition )transition {
@@ -136,21 +136,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setFillOpacity:(MGLStyleValue<NSNumber *> *)fillOpacity {
+- (void)setFillOpacity:(NSExpression *)fillOpacity {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(fillOpacity);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(fillOpacity);
     self.rawLayer->setFillOpacity(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)fillOpacity {
+- (NSExpression *)fillOpacity {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillOpacity();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultFillOpacity());
+        propertyValue = self.rawLayer->getDefaultFillOpacity();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setFillOpacityTransition:(MGLTransition )transition {
@@ -171,21 +171,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setFillOutlineColor:(MGLStyleValue<MGLColor *> *)fillOutlineColor {
+- (void)setFillOutlineColor:(NSExpression *)fillOutlineColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenPropertyValue(fillOutlineColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::Color>>(fillOutlineColor);
     self.rawLayer->setFillOutlineColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)fillOutlineColor {
+- (NSExpression *)fillOutlineColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillOutlineColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(self.rawLayer->getDefaultFillOutlineColor());
+        propertyValue = self.rawLayer->getDefaultFillOutlineColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setFillOutlineColorTransition:(MGLTransition )transition {
@@ -206,21 +206,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setFillPattern:(MGLStyleValue<NSString *> *)fillPattern {
+- (void)setFillPattern:(NSExpression *)fillPattern {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::string, NSString *>().toPropertyValue(fillPattern);
+    auto mbglValue = MGLStyleValueTransformer<std::string, NSString *>().toPropertyValue<mbgl::style::PropertyValue<std::string>>(fillPattern);
     self.rawLayer->setFillPattern(mbglValue);
 }
 
-- (MGLStyleValue<NSString *> *)fillPattern {
+- (NSExpression *)fillPattern {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillPattern();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::string, NSString *>().toStyleValue(self.rawLayer->getDefaultFillPattern());
+        propertyValue = self.rawLayer->getDefaultFillPattern();
     }
-    return MGLStyleValueTransformer<std::string, NSString *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::string, NSString *>().toExpression(propertyValue);
 }
 
 - (void)setFillPatternTransition:(MGLTransition )transition {
@@ -241,21 +241,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setFillTranslation:(MGLStyleValue<NSValue *> *)fillTranslation {
+- (void)setFillTranslation:(NSExpression *)fillTranslation {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toInterpolatablePropertyValue(fillTranslation);
+    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toPropertyValue<mbgl::style::PropertyValue<std::array<float, 2>>>(fillTranslation);
     self.rawLayer->setFillTranslate(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)fillTranslation {
+- (NSExpression *)fillTranslation {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillTranslate();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toStyleValue(self.rawLayer->getDefaultFillTranslate());
+        propertyValue = self.rawLayer->getDefaultFillTranslate();
     }
-    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toExpression(propertyValue);
 }
 
 - (void)setFillTranslationTransition:(MGLTransition )transition {
@@ -276,34 +276,34 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setFillTranslate:(MGLStyleValue<NSValue *> *)fillTranslate {
+- (void)setFillTranslate:(NSExpression *)fillTranslate {
 }
 
-- (MGLStyleValue<NSValue *> *)fillTranslate {
+- (NSExpression *)fillTranslate {
     return self.fillTranslation;
 }
 
-- (void)setFillTranslationAnchor:(MGLStyleValue<NSValue *> *)fillTranslationAnchor {
+- (void)setFillTranslationAnchor:(NSExpression *)fillTranslationAnchor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLFillTranslationAnchor>().toEnumPropertyValue(fillTranslationAnchor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLFillTranslationAnchor>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::TranslateAnchorType>>(fillTranslationAnchor);
     self.rawLayer->setFillTranslateAnchor(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)fillTranslationAnchor {
+- (NSExpression *)fillTranslationAnchor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getFillTranslateAnchor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLFillTranslationAnchor>().toEnumStyleValue(self.rawLayer->getDefaultFillTranslateAnchor());
+        propertyValue = self.rawLayer->getDefaultFillTranslateAnchor();
     }
-    return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLFillTranslationAnchor>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLFillTranslationAnchor>().toExpression(propertyValue);
 }
 
-- (void)setFillTranslateAnchor:(MGLStyleValue<NSValue *> *)fillTranslateAnchor {
+- (void)setFillTranslateAnchor:(NSExpression *)fillTranslateAnchor {
 }
 
-- (MGLStyleValue<NSValue *> *)fillTranslateAnchor {
+- (NSExpression *)fillTranslateAnchor {
     return self.fillTranslationAnchor;
 }
 
diff --git a/platform/darwin/src/MGLHillshadeStyleLayer.h b/platform/darwin/src/MGLHillshadeStyleLayer.h
index 0fe49d510d..c1fa069844 100644
--- a/platform/darwin/src/MGLHillshadeStyleLayer.h
+++ b/platform/darwin/src/MGLHillshadeStyleLayer.h
@@ -2,7 +2,6 @@
 // Edit platform/darwin/scripts/generate-style-code.js, then run `make darwin-style-code`.
 
 #import "MGLFoundation.h"
-#import "MGLStyleValue.h"
 #import "MGLVectorStyleLayer.h"
 
 NS_ASSUME_NONNULL_BEGIN
@@ -59,41 +58,26 @@ MGL_EXPORT
 
 #pragma mark - Accessing the Paint Attributes
 
-#if TARGET_OS_IPHONE
 /**
  The shading color used to accentuate rugged terrain like sharp cliffs and
  gorges.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.blackColor`. Set this property to `nil` to reset it to the default
  value.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *hillshadeAccentColor;
-#else
-/**
- The shading color used to accentuate rugged terrain like sharp cliffs and
- gorges.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.blackColor`. Set this property to `nil` to reset it to the default
- value.
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *hillshadeAccentColor;
-#endif
+@property (nonatomic, null_resettable) NSExpression *hillshadeAccentColor;
 
 /**
  The transition affecting any changes to this layer’s `hillshadeAccentColor` property.
@@ -105,18 +89,21 @@ MGL_EXPORT
 /**
  Intensity of the hillshade
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0.5`. Set this property to `nil` to
- reset it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0.5`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *hillshadeExaggeration;
+@property (nonatomic, null_resettable) NSExpression *hillshadeExaggeration;
 
 /**
  The transition affecting any changes to this layer’s `hillshadeExaggeration` property.
@@ -125,39 +112,25 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition hillshadeExaggerationTransition;
 
-#if TARGET_OS_IPHONE
 /**
  The shading color of areas that faces towards the light source.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.whiteColor`. Set this property to `nil` to reset it to the default
  value.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *hillshadeHighlightColor;
-#else
-/**
- The shading color of areas that faces towards the light source.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.whiteColor`. Set this property to `nil` to reset it to the default
- value.
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *hillshadeHighlightColor;
-#endif
+@property (nonatomic, null_resettable) NSExpression *hillshadeHighlightColor;
 
 /**
  The transition affecting any changes to this layer’s `hillshadeHighlightColor` property.
@@ -169,17 +142,26 @@ MGL_EXPORT
 /**
  Direction of light source when map is rotated.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLHillshadeIlluminationAnchorViewport`. Set this
- property to `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to
+ `viewport`. Set this property to `nil` to reset it to the default value.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ * Constant `MGLHillshadeIlluminationAnchor` values
+ * Any of the following constant string values:
+   * `map`: The hillshade illumination is relative to the north direction.
+   * `viewport`: The hillshade illumination is relative to the top of the
+ viewport.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *hillshadeIlluminationAnchor;
+@property (nonatomic, null_resettable) NSExpression *hillshadeIlluminationAnchor;
 
 /**
  The direction of the light source used to generate the hillshading with 0 as
@@ -187,18 +169,21 @@ MGL_EXPORT
  `MGLHillshadeIlluminationAnchorViewport` and due north if
  `hillshadeIlluminationAnchor` is set to `MGLHillshadeIlluminationAnchorMap`.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `335`. Set this property to `nil` to
- reset it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `335`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *hillshadeIlluminationDirection;
+@property (nonatomic, null_resettable) NSExpression *hillshadeIlluminationDirection;
 
 /**
  The transition affecting any changes to this layer’s `hillshadeIlluminationDirection` property.
@@ -207,39 +192,25 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition hillshadeIlluminationDirectionTransition;
 
-#if TARGET_OS_IPHONE
 /**
  The shading color of areas that face away from the light source.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.blackColor`. Set this property to `nil` to reset it to the default
  value.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *hillshadeShadowColor;
-#else
-/**
- The shading color of areas that face away from the light source.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.blackColor`. Set this property to `nil` to reset it to the default
- value.
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *hillshadeShadowColor;
-#endif
+@property (nonatomic, null_resettable) NSExpression *hillshadeShadowColor;
 
 /**
  The transition affecting any changes to this layer’s `hillshadeShadowColor` property.
diff --git a/platform/darwin/src/MGLHillshadeStyleLayer.mm b/platform/darwin/src/MGLHillshadeStyleLayer.mm
index 3225feb587..ac12b52506 100644
--- a/platform/darwin/src/MGLHillshadeStyleLayer.mm
+++ b/platform/darwin/src/MGLHillshadeStyleLayer.mm
@@ -77,21 +77,21 @@ namespace mbgl {
 
 #pragma mark - Accessing the Paint Attributes
 
-- (void)setHillshadeAccentColor:(MGLStyleValue<MGLColor *> *)hillshadeAccentColor {
+- (void)setHillshadeAccentColor:(NSExpression *)hillshadeAccentColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toInterpolatablePropertyValue(hillshadeAccentColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::PropertyValue<mbgl::Color>>(hillshadeAccentColor);
     self.rawLayer->setHillshadeAccentColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)hillshadeAccentColor {
+- (NSExpression *)hillshadeAccentColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getHillshadeAccentColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toStyleValue(self.rawLayer->getDefaultHillshadeAccentColor());
+        propertyValue = self.rawLayer->getDefaultHillshadeAccentColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setHillshadeAccentColorTransition:(MGLTransition )transition {
@@ -112,21 +112,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setHillshadeExaggeration:(MGLStyleValue<NSNumber *> *)hillshadeExaggeration {
+- (void)setHillshadeExaggeration:(NSExpression *)hillshadeExaggeration {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(hillshadeExaggeration);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(hillshadeExaggeration);
     self.rawLayer->setHillshadeExaggeration(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)hillshadeExaggeration {
+- (NSExpression *)hillshadeExaggeration {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getHillshadeExaggeration();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultHillshadeExaggeration());
+        propertyValue = self.rawLayer->getDefaultHillshadeExaggeration();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setHillshadeExaggerationTransition:(MGLTransition )transition {
@@ -147,21 +147,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setHillshadeHighlightColor:(MGLStyleValue<MGLColor *> *)hillshadeHighlightColor {
+- (void)setHillshadeHighlightColor:(NSExpression *)hillshadeHighlightColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toInterpolatablePropertyValue(hillshadeHighlightColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::PropertyValue<mbgl::Color>>(hillshadeHighlightColor);
     self.rawLayer->setHillshadeHighlightColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)hillshadeHighlightColor {
+- (NSExpression *)hillshadeHighlightColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getHillshadeHighlightColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toStyleValue(self.rawLayer->getDefaultHillshadeHighlightColor());
+        propertyValue = self.rawLayer->getDefaultHillshadeHighlightColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setHillshadeHighlightColorTransition:(MGLTransition )transition {
@@ -182,38 +182,38 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setHillshadeIlluminationAnchor:(MGLStyleValue<NSValue *> *)hillshadeIlluminationAnchor {
+- (void)setHillshadeIlluminationAnchor:(NSExpression *)hillshadeIlluminationAnchor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::HillshadeIlluminationAnchorType, NSValue *, mbgl::style::HillshadeIlluminationAnchorType, MGLHillshadeIlluminationAnchor>().toEnumPropertyValue(hillshadeIlluminationAnchor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::HillshadeIlluminationAnchorType, NSValue *, mbgl::style::HillshadeIlluminationAnchorType, MGLHillshadeIlluminationAnchor>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::HillshadeIlluminationAnchorType>>(hillshadeIlluminationAnchor);
     self.rawLayer->setHillshadeIlluminationAnchor(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)hillshadeIlluminationAnchor {
+- (NSExpression *)hillshadeIlluminationAnchor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getHillshadeIlluminationAnchor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::HillshadeIlluminationAnchorType, NSValue *, mbgl::style::HillshadeIlluminationAnchorType, MGLHillshadeIlluminationAnchor>().toEnumStyleValue(self.rawLayer->getDefaultHillshadeIlluminationAnchor());
+        propertyValue = self.rawLayer->getDefaultHillshadeIlluminationAnchor();
     }
-    return MGLStyleValueTransformer<mbgl::style::HillshadeIlluminationAnchorType, NSValue *, mbgl::style::HillshadeIlluminationAnchorType, MGLHillshadeIlluminationAnchor>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::HillshadeIlluminationAnchorType, NSValue *, mbgl::style::HillshadeIlluminationAnchorType, MGLHillshadeIlluminationAnchor>().toExpression(propertyValue);
 }
 
-- (void)setHillshadeIlluminationDirection:(MGLStyleValue<NSNumber *> *)hillshadeIlluminationDirection {
+- (void)setHillshadeIlluminationDirection:(NSExpression *)hillshadeIlluminationDirection {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(hillshadeIlluminationDirection);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(hillshadeIlluminationDirection);
     self.rawLayer->setHillshadeIlluminationDirection(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)hillshadeIlluminationDirection {
+- (NSExpression *)hillshadeIlluminationDirection {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getHillshadeIlluminationDirection();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultHillshadeIlluminationDirection());
+        propertyValue = self.rawLayer->getDefaultHillshadeIlluminationDirection();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setHillshadeIlluminationDirectionTransition:(MGLTransition )transition {
@@ -234,21 +234,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setHillshadeShadowColor:(MGLStyleValue<MGLColor *> *)hillshadeShadowColor {
+- (void)setHillshadeShadowColor:(NSExpression *)hillshadeShadowColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toInterpolatablePropertyValue(hillshadeShadowColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::PropertyValue<mbgl::Color>>(hillshadeShadowColor);
     self.rawLayer->setHillshadeShadowColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)hillshadeShadowColor {
+- (NSExpression *)hillshadeShadowColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getHillshadeShadowColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toStyleValue(self.rawLayer->getDefaultHillshadeShadowColor());
+        propertyValue = self.rawLayer->getDefaultHillshadeShadowColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setHillshadeShadowColorTransition:(MGLTransition )transition {
diff --git a/platform/darwin/src/MGLLight.h b/platform/darwin/src/MGLLight.h
index 55b789f043..d7e64cbfad 100644
--- a/platform/darwin/src/MGLLight.h
+++ b/platform/darwin/src/MGLLight.h
@@ -27,7 +27,7 @@ typedef NS_ENUM(NSUInteger, MGLLightAnchor) {
  A structure containing information about the position of the light source
  relative to lit geometries.
  */
-typedef struct MGLSphericalPosition {
+typedef struct __attribute__((objc_boxable)) MGLSphericalPosition {
     /** Distance from the center of the base of an object to its light. */
     CGFloat radial;
     /** Position of the light relative to 0° (0° when `MGLLight.anchor` is set to viewport corresponds
@@ -65,20 +65,31 @@ MGL_EXPORT
 /**
  Whether extruded geometries are lit relative to the map or viewport.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLLightAnchorViewport`.
+ The default value of this property is an expression that evaluates to
+ `viewport`.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ * Constant `MGLAnchor` values
+ * Any of the following constant string values:
+   * `map`: The position of the light source is aligned to the rotation of the
+ map.
+   * `viewport`: The position of the light source is aligned to the rotation of
+ the viewport.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
 
  This property corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-js/style-spec/#light-anchor"><code>anchor</code></a>
  light property in the Mapbox Style Specification.
  */
-@property (nonatomic) MGLStyleValue<NSValue *> *anchor;
+@property (nonatomic) NSExpression *anchor;
 
 /**
  Position of the `MGLLight` source relative to lit (extruded) geometries, in a
@@ -90,21 +101,25 @@ MGL_EXPORT
  corresponds to due north, and degrees proceed clockwise), and polar indicates
  the height of the light (from 0°, directly above, to 180°, directly below).
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `MGLSphericalPosition` struct set to 1.15 radial, 210 azimuthal and 30 polar.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLSphericalPosition` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
 
  This property corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-js/style-spec/#light-position"><code>position</code></a>
  light property in the Mapbox Style Specification.
  */
-@property (nonatomic) MGLStyleValue<NSValue *> *position;
+@property (nonatomic) NSExpression *position;
 
 /**
  The transition affecting any changes to this layer’s `position` property.
@@ -113,45 +128,28 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition positionTransition;
 
-#if TARGET_OS_IPHONE
 /**
  Color tint for lighting extruded geometries.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.whiteColor`.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-
- This property corresponds to the <a
- href="https://www.mapbox.com/mapbox-gl-js/style-spec/#light-color"><code>color</code></a>
- light property in the Mapbox Style Specification.
- */
-@property (nonatomic) MGLStyleValue<UIColor *> *color;
-#else
-/**
- Color tint for lighting extruded geometries.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.whiteColor`.
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
 
  This property corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-js/style-spec/#light-color"><code>color</code></a>
  light property in the Mapbox Style Specification.
  */
-@property (nonatomic) MGLStyleValue<NSColor *> *color;
-#endif
+@property (nonatomic) NSExpression *color;
 
 /**
  The transition affecting any changes to this layer’s `color` property.
@@ -164,21 +162,25 @@ MGL_EXPORT
  Intensity of lighting (on a scale from 0 to 1). Higher numbers will present as
  more extreme contrast.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0.5`.
+ The default value of this property is an expression that evaluates to the float
+ `0.5`.
+ 
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
 
  This property corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-js/style-spec/#light-intensity"><code>intensity</code></a>
  light property in the Mapbox Style Specification.
  */
-@property (nonatomic) MGLStyleValue<NSNumber *> *intensity;
+@property (nonatomic) NSExpression *intensity;
 
 /**
  The transition affecting any changes to this layer’s `intensity` property.
diff --git a/platform/darwin/src/MGLLight.h.ejs b/platform/darwin/src/MGLLight.h.ejs
index 26ecefc3af..56c3312107 100644
--- a/platform/darwin/src/MGLLight.h.ejs
+++ b/platform/darwin/src/MGLLight.h.ejs
@@ -33,7 +33,7 @@ typedef NS_ENUM(NSUInteger, MGLLight<%- camelize(property.name) %>) {
  A structure containing information about the position of the light source
  relative to lit geometries.
  */
-typedef struct MGLSphericalPosition {
+typedef struct __attribute__((objc_boxable)) MGLSphericalPosition {
     /** Distance from the center of the base of an object to its light. */
     CGFloat radial;
     /** Position of the light relative to 0° (0° when `MGLLight.anchor` is set to viewport corresponds
@@ -77,7 +77,7 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-js/style-spec/#light-<%- originalPropertyName(property) %>"><code><%- originalPropertyName(property) %></code></a>
  light property in the Mapbox Style Specification.
  */
-@property (nonatomic<% if (property.getter) { %>, getter=<%- objCGetter(property) -%><% } %>) MGLStyleValue<<%- propertyType(property, true) %>> *<%- camelizeWithLeadingLowercase(property.name) %>;
+@property (nonatomic<% if (property.getter) { %>, getter=<%- objCGetter(property) -%><% } %>) NSExpression *<%- camelizeWithLeadingLowercase(property.name) %>;
 
 <% if (property.transition) { -%>
 /**
@@ -89,7 +89,7 @@ MGL_EXPORT
 
 <% } -%>
 <% if (property.original) { -%>
-@property (nonatomic<% if (!property.required) { %>, null_resettable<% } %>) MGLStyleValue<<%- propertyType(property, true) %>> *<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> __attribute__((unavailable("Use <%- camelizeWithLeadingLowercase(property.name) %> instead.")));
+@property (nonatomic<% if (!property.required) { %>, null_resettable<% } %>) NSExpression *<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> __attribute__((unavailable("Use <%- camelizeWithLeadingLowercase(property.name) %> instead.")));
 
 <% } -%>
 <% } -%>
diff --git a/platform/darwin/src/MGLLight.mm b/platform/darwin/src/MGLLight.mm
index c83ef127a6..db2893ed44 100644
--- a/platform/darwin/src/MGLLight.mm
+++ b/platform/darwin/src/MGLLight.mm
@@ -44,39 +44,39 @@ NS_INLINE mbgl::style::TransitionOptions MGLOptionsFromTransition(MGLTransition
 {
     if (self = [super init]) {
         auto anchor = mbglLight->getAnchor();
-        MGLStyleValue<NSValue *> *anchorStyleValue;
+        NSExpression *anchorExpression;
         if (anchor.isUndefined()) {
             mbgl::style::PropertyValue<mbgl::style::LightAnchorType> defaultAnchor = mbglLight->getDefaultAnchor();
-            anchorStyleValue = MGLStyleValueTransformer<mbgl::style::LightAnchorType, NSValue *, mbgl::style::LightAnchorType, MGLLightAnchor>().toEnumStyleValue(defaultAnchor);
+            anchorExpression = MGLStyleValueTransformer<mbgl::style::LightAnchorType, NSValue *, mbgl::style::LightAnchorType, MGLLightAnchor>().toExpression(defaultAnchor);
         } else {
-            anchorStyleValue = MGLStyleValueTransformer<mbgl::style::LightAnchorType, NSValue *, mbgl::style::LightAnchorType, MGLLightAnchor>().toEnumStyleValue(anchor);
+            anchorExpression = MGLStyleValueTransformer<mbgl::style::LightAnchorType, NSValue *, mbgl::style::LightAnchorType, MGLLightAnchor>().toExpression(anchor);
         }
 
-        _anchor = anchorStyleValue;
+        _anchor = anchorExpression;
 
         auto positionValue = mbglLight->getPosition();
         if (positionValue.isUndefined()) {
-            _position = MGLStyleValueTransformer<mbgl::style::Position, NSValue *>().toStyleValue(mbglLight->getDefaultPosition());
+            _position = MGLStyleValueTransformer<mbgl::style::Position, NSValue *>().toExpression(mbglLight->getDefaultPosition());
         } else {
-            _position = MGLStyleValueTransformer<mbgl::style::Position, NSValue *>().toStyleValue(positionValue);
+            _position = MGLStyleValueTransformer<mbgl::style::Position, NSValue *>().toExpression(positionValue);
         }
         
         _positionTransition = MGLTransitionFromOptions(mbglLight->getPositionTransition());
  
         auto colorValue = mbglLight->getColor();
         if (colorValue.isUndefined()) {
-            _color = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toStyleValue(mbglLight->getDefaultColor());
+            _color = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(mbglLight->getDefaultColor());
         } else {
-            _color = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toStyleValue(colorValue);
+            _color = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(colorValue);
         }
         
         _colorTransition = MGLTransitionFromOptions(mbglLight->getColorTransition());
  
         auto intensityValue = mbglLight->getIntensity();
         if (intensityValue.isUndefined()) {
-            _intensity = MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(mbglLight->getDefaultIntensity());
+            _intensity = MGLStyleValueTransformer<float, NSNumber *>().toExpression(mbglLight->getDefaultIntensity());
         } else {
-            _intensity = MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(intensityValue);
+            _intensity = MGLStyleValueTransformer<float, NSNumber *>().toExpression(intensityValue);
         }
         
         _intensityTransition = MGLTransitionFromOptions(mbglLight->getIntensityTransition());
@@ -89,20 +89,20 @@ NS_INLINE mbgl::style::TransitionOptions MGLOptionsFromTransition(MGLTransition
 - (mbgl::style::Light)mbglLight
 {
     mbgl::style::Light mbglLight;
-    auto anchor = MGLStyleValueTransformer<mbgl::style::LightAnchorType, NSValue *, mbgl::style::LightAnchorType, MGLLightAnchor>().toEnumPropertyValue(self.anchor);
+    auto anchor = MGLStyleValueTransformer<mbgl::style::LightAnchorType, NSValue *, mbgl::style::LightAnchorType, MGLLightAnchor>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::LightAnchorType>>(self.anchor);
     mbglLight.setAnchor(anchor);
 
-    auto position = MGLStyleValueTransformer<mbgl::style::Position, NSValue *>().toInterpolatablePropertyValue(self.position);
+    auto position = MGLStyleValueTransformer<mbgl::style::Position, NSValue *>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::Position>>(self.position);
     mbglLight.setPosition(position);
  
     mbglLight.setPositionTransition(MGLOptionsFromTransition(self.positionTransition));
 
-    auto color = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toInterpolatablePropertyValue(self.color);
+    auto color = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::PropertyValue<mbgl::Color>>(self.color);
     mbglLight.setColor(color);
  
     mbglLight.setColorTransition(MGLOptionsFromTransition(self.colorTransition));
 
-    auto intensity = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(self.intensity);
+    auto intensity = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(self.intensity);
     mbglLight.setIntensity(intensity);
  
     mbglLight.setIntensityTransition(MGLOptionsFromTransition(self.intensityTransition));
diff --git a/platform/darwin/src/MGLLight.mm.ejs b/platform/darwin/src/MGLLight.mm.ejs
index 0d0da124c8..b241269519 100644
--- a/platform/darwin/src/MGLLight.mm.ejs
+++ b/platform/darwin/src/MGLLight.mm.ejs
@@ -55,15 +55,15 @@ NS_INLINE mbgl::style::TransitionOptions MGLOptionsFromTransition(MGLTransition
 <% for (const property of properties) { -%>
 <% if (property.type == "enum") { -%>
         auto <%- camelizeWithLeadingLowercase(property.name) -%> = mbglLight->get<%- camelize(property.name) -%>();
-        MGLStyleValue<NSValue *> *<%- camelizeWithLeadingLowercase(property.name) -%>StyleValue;
+        NSExpression *<%- camelizeWithLeadingLowercase(property.name) -%>Expression;
         if (<%- camelizeWithLeadingLowercase(property.name) -%>.isUndefined()) {
             mbgl::style::PropertyValue<mbgl::style::Light<%- camelize(property.name) -%>Type> default<%- camelize(property.name) -%> = mbglLight->getDefault<%- camelize(property.name) -%>();
-            <%- camelizeWithLeadingLowercase(property.name) -%>StyleValue = MGLStyleValueTransformer<mbgl::style::LightAnchorType, NSValue *, mbgl::style::Light<%- camelize(property.name) -%>Type, MGLLight<%- camelize(property.name) -%>>().toEnumStyleValue(default<%- camelize(property.name) -%>);
+            <%- camelizeWithLeadingLowercase(property.name) -%>Expression = MGLStyleValueTransformer<mbgl::style::LightAnchorType, NSValue *, mbgl::style::Light<%- camelize(property.name) -%>Type, MGLLight<%- camelize(property.name) -%>>().toExpression(default<%- camelize(property.name) -%>);
         } else {
-            <%- camelizeWithLeadingLowercase(property.name) -%>StyleValue = MGLStyleValueTransformer<mbgl::style::Light<%- camelize(property.name) -%>Type, NSValue *, mbgl::style::Light<%- camelize(property.name) -%>Type, MGLLight<%- camelize(property.name) -%>>().toEnumStyleValue(<%- camelizeWithLeadingLowercase(property.name) -%>);
+            <%- camelizeWithLeadingLowercase(property.name) -%>Expression = MGLStyleValueTransformer<mbgl::style::Light<%- camelize(property.name) -%>Type, NSValue *, mbgl::style::Light<%- camelize(property.name) -%>Type, MGLLight<%- camelize(property.name) -%>>().toExpression(<%- camelizeWithLeadingLowercase(property.name) -%>);
         }
 
-        _<%- camelizeWithLeadingLowercase(property.name) -%> = <%- camelizeWithLeadingLowercase(property.name) -%>StyleValue;
+        _<%- camelizeWithLeadingLowercase(property.name) -%> = <%- camelizeWithLeadingLowercase(property.name) -%>Expression;
 
 <% if (property.transition) { -%>
         _<%- camelizeWithLeadingLowercase(property.name) -%>Transition = MGLTransitionFromOptions(mbglLight->get<%- camelize(property.name) -%>Transition());
@@ -72,9 +72,9 @@ NS_INLINE mbgl::style::TransitionOptions MGLOptionsFromTransition(MGLTransition
 <% } else {-%>
         auto <%- camelizeWithLeadingLowercase(property.name) -%>Value = mbglLight->get<%- camelize(property.name) -%>();
         if (<%- camelizeWithLeadingLowercase(property.name) -%>Value.isUndefined()) {
-            _<%- camelizeWithLeadingLowercase(property.name) -%> = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toStyleValue(mbglLight->getDefault<%- camelize(property.name) -%>());
+            _<%- camelizeWithLeadingLowercase(property.name) -%> = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toExpression(mbglLight->getDefault<%- camelize(property.name) -%>());
         } else {
-            _<%- camelizeWithLeadingLowercase(property.name) -%> = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toStyleValue(<%- camelizeWithLeadingLowercase(property.name) -%>Value);
+            _<%- camelizeWithLeadingLowercase(property.name) -%> = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toExpression(<%- camelizeWithLeadingLowercase(property.name) -%>Value);
         }
 <% if (property.transition) { -%>        
         _<%- camelizeWithLeadingLowercase(property.name) -%>Transition = MGLTransitionFromOptions(mbglLight->get<%- camelize(property.name) -%>Transition());
@@ -93,11 +93,11 @@ NS_INLINE mbgl::style::TransitionOptions MGLOptionsFromTransition(MGLTransition
 <% if (properties.length) { -%>
 <% for (const property of properties) { -%>
 <% if (property.type == "enum") { -%>
-    auto <%- camelizeWithLeadingLowercase(property.name) -%> = MGLStyleValueTransformer<mbgl::style::Light<%- camelize(property.name) -%>Type, NSValue *, mbgl::style::Light<%- camelize(property.name) -%>Type, MGLLight<%- camelize(property.name) -%>>().toEnumPropertyValue(self.<%- camelizeWithLeadingLowercase(property.name) -%>);
+    auto <%- camelizeWithLeadingLowercase(property.name) -%> = MGLStyleValueTransformer<mbgl::style::Light<%- camelize(property.name) -%>Type, NSValue *, mbgl::style::Light<%- camelize(property.name) -%>Type, MGLLight<%- camelize(property.name) -%>>().toPropertyValue<mbgl::style::PropertyValue<<%- valueTransformerArguments(property)[0] %>>>(self.<%- camelizeWithLeadingLowercase(property.name) -%>);
     mbglLight.set<%- camelize(property.name) -%>(<%- camelizeWithLeadingLowercase(property.name) -%>);
 
 <% } else {-%>
-    auto <%- camelizeWithLeadingLowercase(property.name) -%> = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toInterpolatablePropertyValue(self.<%- camelizeWithLeadingLowercase(property.name) -%>);
+    auto <%- camelizeWithLeadingLowercase(property.name) -%> = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toPropertyValue<mbgl::style::PropertyValue<<%- valueTransformerArguments(property)[0] %>>>(self.<%- camelizeWithLeadingLowercase(property.name) -%>);
     mbglLight.set<%- camelize(property.name) -%>(<%- camelizeWithLeadingLowercase(property.name) -%>);
  
 <% } -%>
diff --git a/platform/darwin/src/MGLLineStyleLayer.h b/platform/darwin/src/MGLLineStyleLayer.h
index e48951d97b..003f48ae43 100644
--- a/platform/darwin/src/MGLLineStyleLayer.h
+++ b/platform/darwin/src/MGLLineStyleLayer.h
@@ -2,7 +2,6 @@
 // Edit platform/darwin/scripts/generate-style-code.js, then run `make darwin-style-code`.
 
 #import "MGLFoundation.h"
-#import "MGLStyleValue.h"
 #import "MGLVectorStyleLayer.h"
 
 NS_ASSUME_NONNULL_BEGIN
@@ -94,12 +93,11 @@ typedef NS_ENUM(NSUInteger, MGLLineTranslationAnchor) {
  ```swift
  let layer = MGLLineStyleLayer(identifier: "trails-path", source: trails)
  layer.sourceLayerIdentifier = "trails"
- layer.lineWidth = MGLStyleValue(interpolationMode: .exponential,
-                                 cameraStops: [14: MGLStyleValue(rawValue: 2),
-                                               18: MGLStyleValue(rawValue: 20)],
-                                 options: [.interpolationBase: 1.5])
- layer.lineColor = MGLStyleValue(rawValue: .brown)
- layer.lineCap = MGLStyleValue(rawValue: NSValue(mglLineCap: .round))
+ layer.lineWidth = NSExpression(format: "FUNCTION($zoomLevel, 'mgl_interpolateWithCurveType:parameters:stops:', 'exponential', 1.5, %@)",
+                                [14: 2,
+                                 18: 20])
+ layer.lineColor = NSExpression(forConstantValue: UIColor.brown)
+ layer.lineCap = NSExpression(forConstantValue: "round")
  layer.predicate = NSPredicate(format: "%K == %@", "trail-type", "mountain-biking")
  mapView.style?.addLayer(layer)
  ```
@@ -127,82 +125,99 @@ MGL_EXPORT
 /**
  The display of line endings.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLLineCapButt`. Set this property to `nil` to
- reset it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ The default value of this property is an expression that evaluates to `butt`.
+ Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLLineCap` values
+ * Any of the following constant string values:
+   * `butt`: A cap with a squared-off end which is drawn to the exact endpoint
+ of the line.
+   * `round`: A cap with a rounded end which is drawn beyond the endpoint of the
+ line at a radius of one-half of the line's width and centered on the endpoint
+ of the line.
+   * `square`: A cap with a squared-off end which is drawn beyond the endpoint
+ of the line at a distance of one-half of the line's width.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *lineCap;
+@property (nonatomic, null_resettable) NSExpression *lineCap;
 
 /**
  The display of lines when joining.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLLineJoinMiter`. Set this property to `nil` to
- reset it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to `miter`.
+ Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLLineJoin` values
+ * Any of the following constant string values:
+   * `bevel`: A join with a squared-off end which is drawn beyond the endpoint
+ of the line at a distance of one-half of the line's width.
+   * `round`: A join with a rounded end which is drawn beyond the endpoint of
+ the line at a radius of one-half of the line's width and centered on the
+ endpoint of the line.
+   * `miter`: A join with a sharp, angled corner which is drawn with the outer
+ sides beyond the endpoint of the path until they meet.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *lineJoin;
+@property (nonatomic, null_resettable) NSExpression *lineJoin;
 
 /**
  Used to automatically convert miter joins to bevel joins for sharp angles.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `2`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `2`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `lineJoin` is set to an
- `MGLStyleValue` object containing an `NSValue` object containing
- `MGLLineJoinMiter`. Otherwise, it is ignored.
+ expression that evaluates to `miter`. Otherwise, it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *lineMiterLimit;
+@property (nonatomic, null_resettable) NSExpression *lineMiterLimit;
 
 /**
  Used to automatically convert round joins to miter joins for shallow angles.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1.05`. Set this property to `nil` to
- reset it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `1.05`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `lineJoin` is set to an
- `MGLStyleValue` object containing an `NSValue` object containing
- `MGLLineJoinRound`. Otherwise, it is ignored.
+ expression that evaluates to `round`. Otherwise, it is ignored.
+ 
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *lineRoundLimit;
+@property (nonatomic, null_resettable) NSExpression *lineRoundLimit;
 
 #pragma mark - Accessing the Paint Attributes
 
@@ -211,27 +226,19 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *lineBlur;
+@property (nonatomic, null_resettable) NSExpression *lineBlur;
 
 /**
  The transition affecting any changes to this layer’s `lineBlur` property.
@@ -240,63 +247,26 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition lineBlurTransition;
 
-#if TARGET_OS_IPHONE
 /**
  The color with which the line will be drawn.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.blackColor`. Set this property to `nil` to reset it to the default
  value.
  
  This property is only applied to the style if `linePattern` is set to `nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *lineColor;
-#else
-/**
- The color with which the line will be drawn.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.blackColor`. Set this property to `nil` to reset it to the default
- value.
- 
- This property is only applied to the style if `linePattern` is set to `nil`.
- Otherwise, it is ignored.
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *lineColor;
-#endif
+@property (nonatomic, null_resettable) NSExpression *lineColor;
 
 /**
  The transition affecting any changes to this layer’s `lineColor` property.
@@ -319,13 +289,19 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-line-dasharray"><code>line-dasharray</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ * Constant array values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSArray<NSNumber *> *> *lineDashPattern;
+@property (nonatomic, null_resettable) NSExpression *lineDashPattern;
 
 /**
  The transition affecting any changes to this layer’s `lineDashPattern` property.
@@ -334,7 +310,7 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition lineDashPatternTransition;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSArray<NSNumber *> *> *lineDasharray __attribute__((unavailable("Use lineDashPattern instead.")));
+@property (nonatomic, null_resettable) NSExpression *lineDasharray __attribute__((unavailable("Use lineDashPattern instead.")));
 
 /**
  Draws a line casing outside of a line's actual path. Value indicates the width
@@ -342,27 +318,19 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *lineGapWidth;
+@property (nonatomic, null_resettable) NSExpression *lineGapWidth;
 
 /**
  The transition affecting any changes to this layer’s `lineGapWidth` property.
@@ -379,27 +347,19 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *lineOffset;
+@property (nonatomic, null_resettable) NSExpression *lineOffset;
 
 /**
  The transition affecting any changes to this layer’s `lineOffset` property.
@@ -411,27 +371,19 @@ MGL_EXPORT
 /**
  The opacity at which the line will be drawn.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1`. Set this property to `nil` to reset
- it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to the float
+ `1`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *lineOpacity;
+@property (nonatomic, null_resettable) NSExpression *lineOpacity;
 
 /**
  The transition affecting any changes to this layer’s `lineOpacity` property.
@@ -444,13 +396,19 @@ MGL_EXPORT
  Name of image in style images to use for drawing image lines. For seamless
  patterns, image width must be a factor of two (2, 4, 8, ..., 512).
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant string values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSString *> *linePattern;
+@property (nonatomic, null_resettable) NSExpression *linePattern;
 
 /**
  The transition affecting any changes to this layer’s `linePattern` property.
@@ -465,7 +423,7 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 points rightward and 0
  points downward. Set this property to `nil` to reset it to the default value.
  
@@ -473,21 +431,25 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-line-translate"><code>line-translate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *lineTranslation;
+@property (nonatomic, null_resettable) NSExpression *lineTranslation;
 #else
 /**
  The geometry's offset.
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 points rightward and 0
  points upward. Set this property to `nil` to reset it to the default value.
  
@@ -495,14 +457,18 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-line-translate"><code>line-translate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *lineTranslation;
+@property (nonatomic, null_resettable) NSExpression *lineTranslation;
 #endif
 
 /**
@@ -512,14 +478,13 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition lineTranslationTransition;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *lineTranslate __attribute__((unavailable("Use lineTranslation instead.")));
+@property (nonatomic, null_resettable) NSExpression *lineTranslate __attribute__((unavailable("Use lineTranslation instead.")));
 
 /**
  Controls the frame of reference for `lineTranslation`.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLLineTranslationAnchorMap`. Set this property to
- `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `map`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `lineTranslation` is non-`nil`.
  Otherwise, it is ignored.
@@ -528,42 +493,43 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-line-translate-anchor"><code>line-translate-anchor</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ * Constant `MGLLineTranslationAnchor` values
+ * Any of the following constant string values:
+   * `map`: The line is translated relative to the map.
+   * `viewport`: The line is translated relative to the viewport.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *lineTranslationAnchor;
+@property (nonatomic, null_resettable) NSExpression *lineTranslationAnchor;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *lineTranslateAnchor __attribute__((unavailable("Use lineTranslationAnchor instead.")));
+@property (nonatomic, null_resettable) NSExpression *lineTranslateAnchor __attribute__((unavailable("Use lineTranslationAnchor instead.")));
 
 /**
  Stroke thickness.
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1`. Set this property to `nil` to reset
- it to the default value.
- 
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ The default value of this property is an expression that evaluates to the float
+ `1`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *lineWidth;
+@property (nonatomic, null_resettable) NSExpression *lineWidth;
 
 /**
  The transition affecting any changes to this layer’s `lineWidth` property.
diff --git a/platform/darwin/src/MGLLineStyleLayer.mm b/platform/darwin/src/MGLLineStyleLayer.mm
index 5b2652cdeb..4e6ff27b39 100644
--- a/platform/darwin/src/MGLLineStyleLayer.mm
+++ b/platform/darwin/src/MGLLineStyleLayer.mm
@@ -89,91 +89,91 @@ namespace mbgl {
 
 #pragma mark - Accessing the Layout Attributes
 
-- (void)setLineCap:(MGLStyleValue<NSValue *> *)lineCap {
+- (void)setLineCap:(NSExpression *)lineCap {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::LineCapType, NSValue *, mbgl::style::LineCapType, MGLLineCap>().toEnumPropertyValue(lineCap);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::LineCapType, NSValue *, mbgl::style::LineCapType, MGLLineCap>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::LineCapType>>(lineCap);
     self.rawLayer->setLineCap(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)lineCap {
+- (NSExpression *)lineCap {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineCap();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::LineCapType, NSValue *, mbgl::style::LineCapType, MGLLineCap>().toEnumStyleValue(self.rawLayer->getDefaultLineCap());
+        propertyValue = self.rawLayer->getDefaultLineCap();
     }
-    return MGLStyleValueTransformer<mbgl::style::LineCapType, NSValue *, mbgl::style::LineCapType, MGLLineCap>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::LineCapType, NSValue *, mbgl::style::LineCapType, MGLLineCap>().toExpression(propertyValue);
 }
 
-- (void)setLineJoin:(MGLStyleValue<NSValue *> *)lineJoin {
+- (void)setLineJoin:(NSExpression *)lineJoin {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::LineJoinType, NSValue *, mbgl::style::LineJoinType, MGLLineJoin>().toDataDrivenPropertyValue(lineJoin);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::LineJoinType, NSValue *, mbgl::style::LineJoinType, MGLLineJoin>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::style::LineJoinType>>(lineJoin);
     self.rawLayer->setLineJoin(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)lineJoin {
+- (NSExpression *)lineJoin {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineJoin();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::LineJoinType, NSValue *, mbgl::style::LineJoinType, MGLLineJoin>().toDataDrivenStyleValue(self.rawLayer->getDefaultLineJoin());
+        propertyValue = self.rawLayer->getDefaultLineJoin();
     }
-    return MGLStyleValueTransformer<mbgl::style::LineJoinType, NSValue *, mbgl::style::LineJoinType, MGLLineJoin>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::LineJoinType, NSValue *, mbgl::style::LineJoinType, MGLLineJoin>().toExpression(propertyValue);
 }
 
-- (void)setLineMiterLimit:(MGLStyleValue<NSNumber *> *)lineMiterLimit {
+- (void)setLineMiterLimit:(NSExpression *)lineMiterLimit {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(lineMiterLimit);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(lineMiterLimit);
     self.rawLayer->setLineMiterLimit(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)lineMiterLimit {
+- (NSExpression *)lineMiterLimit {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineMiterLimit();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultLineMiterLimit());
+        propertyValue = self.rawLayer->getDefaultLineMiterLimit();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setLineRoundLimit:(MGLStyleValue<NSNumber *> *)lineRoundLimit {
+- (void)setLineRoundLimit:(NSExpression *)lineRoundLimit {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(lineRoundLimit);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(lineRoundLimit);
     self.rawLayer->setLineRoundLimit(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)lineRoundLimit {
+- (NSExpression *)lineRoundLimit {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineRoundLimit();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultLineRoundLimit());
+        propertyValue = self.rawLayer->getDefaultLineRoundLimit();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 #pragma mark - Accessing the Paint Attributes
 
-- (void)setLineBlur:(MGLStyleValue<NSNumber *> *)lineBlur {
+- (void)setLineBlur:(NSExpression *)lineBlur {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(lineBlur);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(lineBlur);
     self.rawLayer->setLineBlur(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)lineBlur {
+- (NSExpression *)lineBlur {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineBlur();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultLineBlur());
+        propertyValue = self.rawLayer->getDefaultLineBlur();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setLineBlurTransition:(MGLTransition )transition {
@@ -194,21 +194,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setLineColor:(MGLStyleValue<MGLColor *> *)lineColor {
+- (void)setLineColor:(NSExpression *)lineColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenPropertyValue(lineColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::Color>>(lineColor);
     self.rawLayer->setLineColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)lineColor {
+- (NSExpression *)lineColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(self.rawLayer->getDefaultLineColor());
+        propertyValue = self.rawLayer->getDefaultLineColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setLineColorTransition:(MGLTransition )transition {
@@ -229,21 +229,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setLineDashPattern:(MGLStyleValue<NSArray<NSNumber *> *> *)lineDashPattern {
+- (void)setLineDashPattern:(NSExpression *)lineDashPattern {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::vector<float>, NSArray<NSNumber *> *, float>().toPropertyValue(lineDashPattern);
+    auto mbglValue = MGLStyleValueTransformer<std::vector<float>, NSArray<NSNumber *> *, float>().toPropertyValue<mbgl::style::PropertyValue<std::vector<float>>>(lineDashPattern);
     self.rawLayer->setLineDasharray(mbglValue);
 }
 
-- (MGLStyleValue<NSArray<NSNumber *> *> *)lineDashPattern {
+- (NSExpression *)lineDashPattern {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineDasharray();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::vector<float>, NSArray<NSNumber *> *, float>().toStyleValue(self.rawLayer->getDefaultLineDasharray());
+        propertyValue = self.rawLayer->getDefaultLineDasharray();
     }
-    return MGLStyleValueTransformer<std::vector<float>, NSArray<NSNumber *> *, float>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::vector<float>, NSArray<NSNumber *> *, float>().toExpression(propertyValue);
 }
 
 - (void)setLineDashPatternTransition:(MGLTransition )transition {
@@ -264,28 +264,28 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setLineDasharray:(MGLStyleValue<NSArray<NSNumber *> *> *)lineDasharray {
+- (void)setLineDasharray:(NSExpression *)lineDasharray {
 }
 
-- (MGLStyleValue<NSArray<NSNumber *> *> *)lineDasharray {
+- (NSExpression *)lineDasharray {
     return self.lineDashPattern;
 }
 
-- (void)setLineGapWidth:(MGLStyleValue<NSNumber *> *)lineGapWidth {
+- (void)setLineGapWidth:(NSExpression *)lineGapWidth {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(lineGapWidth);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(lineGapWidth);
     self.rawLayer->setLineGapWidth(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)lineGapWidth {
+- (NSExpression *)lineGapWidth {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineGapWidth();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultLineGapWidth());
+        propertyValue = self.rawLayer->getDefaultLineGapWidth();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setLineGapWidthTransition:(MGLTransition )transition {
@@ -306,21 +306,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setLineOffset:(MGLStyleValue<NSNumber *> *)lineOffset {
+- (void)setLineOffset:(NSExpression *)lineOffset {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(lineOffset);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(lineOffset);
     self.rawLayer->setLineOffset(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)lineOffset {
+- (NSExpression *)lineOffset {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineOffset();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultLineOffset());
+        propertyValue = self.rawLayer->getDefaultLineOffset();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setLineOffsetTransition:(MGLTransition )transition {
@@ -341,21 +341,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setLineOpacity:(MGLStyleValue<NSNumber *> *)lineOpacity {
+- (void)setLineOpacity:(NSExpression *)lineOpacity {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(lineOpacity);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(lineOpacity);
     self.rawLayer->setLineOpacity(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)lineOpacity {
+- (NSExpression *)lineOpacity {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineOpacity();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultLineOpacity());
+        propertyValue = self.rawLayer->getDefaultLineOpacity();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setLineOpacityTransition:(MGLTransition )transition {
@@ -376,21 +376,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setLinePattern:(MGLStyleValue<NSString *> *)linePattern {
+- (void)setLinePattern:(NSExpression *)linePattern {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::string, NSString *>().toPropertyValue(linePattern);
+    auto mbglValue = MGLStyleValueTransformer<std::string, NSString *>().toPropertyValue<mbgl::style::PropertyValue<std::string>>(linePattern);
     self.rawLayer->setLinePattern(mbglValue);
 }
 
-- (MGLStyleValue<NSString *> *)linePattern {
+- (NSExpression *)linePattern {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLinePattern();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::string, NSString *>().toStyleValue(self.rawLayer->getDefaultLinePattern());
+        propertyValue = self.rawLayer->getDefaultLinePattern();
     }
-    return MGLStyleValueTransformer<std::string, NSString *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::string, NSString *>().toExpression(propertyValue);
 }
 
 - (void)setLinePatternTransition:(MGLTransition )transition {
@@ -411,21 +411,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setLineTranslation:(MGLStyleValue<NSValue *> *)lineTranslation {
+- (void)setLineTranslation:(NSExpression *)lineTranslation {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toInterpolatablePropertyValue(lineTranslation);
+    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toPropertyValue<mbgl::style::PropertyValue<std::array<float, 2>>>(lineTranslation);
     self.rawLayer->setLineTranslate(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)lineTranslation {
+- (NSExpression *)lineTranslation {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineTranslate();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toStyleValue(self.rawLayer->getDefaultLineTranslate());
+        propertyValue = self.rawLayer->getDefaultLineTranslate();
     }
-    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toExpression(propertyValue);
 }
 
 - (void)setLineTranslationTransition:(MGLTransition )transition {
@@ -446,52 +446,52 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setLineTranslate:(MGLStyleValue<NSValue *> *)lineTranslate {
+- (void)setLineTranslate:(NSExpression *)lineTranslate {
 }
 
-- (MGLStyleValue<NSValue *> *)lineTranslate {
+- (NSExpression *)lineTranslate {
     return self.lineTranslation;
 }
 
-- (void)setLineTranslationAnchor:(MGLStyleValue<NSValue *> *)lineTranslationAnchor {
+- (void)setLineTranslationAnchor:(NSExpression *)lineTranslationAnchor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLLineTranslationAnchor>().toEnumPropertyValue(lineTranslationAnchor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLLineTranslationAnchor>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::TranslateAnchorType>>(lineTranslationAnchor);
     self.rawLayer->setLineTranslateAnchor(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)lineTranslationAnchor {
+- (NSExpression *)lineTranslationAnchor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineTranslateAnchor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLLineTranslationAnchor>().toEnumStyleValue(self.rawLayer->getDefaultLineTranslateAnchor());
+        propertyValue = self.rawLayer->getDefaultLineTranslateAnchor();
     }
-    return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLLineTranslationAnchor>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLLineTranslationAnchor>().toExpression(propertyValue);
 }
 
-- (void)setLineTranslateAnchor:(MGLStyleValue<NSValue *> *)lineTranslateAnchor {
+- (void)setLineTranslateAnchor:(NSExpression *)lineTranslateAnchor {
 }
 
-- (MGLStyleValue<NSValue *> *)lineTranslateAnchor {
+- (NSExpression *)lineTranslateAnchor {
     return self.lineTranslationAnchor;
 }
 
-- (void)setLineWidth:(MGLStyleValue<NSNumber *> *)lineWidth {
+- (void)setLineWidth:(NSExpression *)lineWidth {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(lineWidth);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(lineWidth);
     self.rawLayer->setLineWidth(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)lineWidth {
+- (NSExpression *)lineWidth {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getLineWidth();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultLineWidth());
+        propertyValue = self.rawLayer->getDefaultLineWidth();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setLineWidthTransition:(MGLTransition )transition {
diff --git a/platform/darwin/src/MGLRasterStyleLayer.h b/platform/darwin/src/MGLRasterStyleLayer.h
index e808bb5242..55d49329c2 100644
--- a/platform/darwin/src/MGLRasterStyleLayer.h
+++ b/platform/darwin/src/MGLRasterStyleLayer.h
@@ -2,7 +2,6 @@
 // Edit platform/darwin/scripts/generate-style-code.js, then run `make darwin-style-code`.
 
 #import "MGLFoundation.h"
-#import "MGLStyleValue.h"
 #import "MGLForegroundStyleLayer.h"
 
 NS_ASSUME_NONNULL_BEGIN
@@ -29,7 +28,7 @@ NS_ASSUME_NONNULL_BEGIN
 
  ```swift
  let layer = MGLRasterStyleLayer(identifier: "clouds", source: source)
- layer.rasterOpacity = MGLStyleValue(rawValue: 0.5)
+ layer.rasterOpacity = NSExpression(forConstantValue: 0.5)
  mapView.style?.addLayer(layer)
  ```
  */
@@ -57,22 +56,25 @@ MGL_EXPORT
  Increase or reduce the brightness of the image. The value is the maximum
  brightness.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `1`. Set this property to `nil` to reset it to the default value.
  
  This attribute corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-raster-brightness-max"><code>raster-brightness-max</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *maximumRasterBrightness;
+@property (nonatomic, null_resettable) NSExpression *maximumRasterBrightness;
 
 /**
  The transition affecting any changes to this layer’s `maximumRasterBrightness` property.
@@ -81,28 +83,31 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition maximumRasterBrightnessTransition;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *rasterBrightnessMax __attribute__((unavailable("Use maximumRasterBrightness instead.")));
+@property (nonatomic, null_resettable) NSExpression *rasterBrightnessMax __attribute__((unavailable("Use maximumRasterBrightness instead.")));
 
 /**
  Increase or reduce the brightness of the image. The value is the minimum
  brightness.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
  
  This attribute corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-raster-brightness-min"><code>raster-brightness-min</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *minimumRasterBrightness;
+@property (nonatomic, null_resettable) NSExpression *minimumRasterBrightness;
 
 /**
  The transition affecting any changes to this layer’s `minimumRasterBrightness` property.
@@ -111,23 +116,26 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition minimumRasterBrightnessTransition;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *rasterBrightnessMin __attribute__((unavailable("Use minimumRasterBrightness instead.")));
+@property (nonatomic, null_resettable) NSExpression *rasterBrightnessMin __attribute__((unavailable("Use minimumRasterBrightness instead.")));
 
 /**
  Increase or reduce the contrast of the image.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *rasterContrast;
+@property (nonatomic, null_resettable) NSExpression *rasterContrast;
 
 /**
  The transition affecting any changes to this layer’s `rasterContrast` property.
@@ -141,40 +149,46 @@ MGL_EXPORT
  
  This property is measured in milliseconds.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `300`. Set this property to `nil` to
- reset it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `300`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *rasterFadeDuration;
+@property (nonatomic, null_resettable) NSExpression *rasterFadeDuration;
 
 /**
  Rotates hues around the color wheel.
  
  This property is measured in degrees.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
  
  This attribute corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-raster-hue-rotate"><code>raster-hue-rotate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *rasterHueRotation;
+@property (nonatomic, null_resettable) NSExpression *rasterHueRotation;
 
 /**
  The transition affecting any changes to this layer’s `rasterHueRotation` property.
@@ -183,23 +197,26 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition rasterHueRotationTransition;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *rasterHueRotate __attribute__((unavailable("Use rasterHueRotation instead.")));
+@property (nonatomic, null_resettable) NSExpression *rasterHueRotate __attribute__((unavailable("Use rasterHueRotation instead.")));
 
 /**
  The opacity at which the image will be drawn.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `1`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *rasterOpacity;
+@property (nonatomic, null_resettable) NSExpression *rasterOpacity;
 
 /**
  The transition affecting any changes to this layer’s `rasterOpacity` property.
@@ -211,18 +228,21 @@ MGL_EXPORT
 /**
  Increase or reduce the saturation of the image.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *rasterSaturation;
+@property (nonatomic, null_resettable) NSExpression *rasterSaturation;
 
 /**
  The transition affecting any changes to this layer’s `rasterSaturation` property.
diff --git a/platform/darwin/src/MGLRasterStyleLayer.mm b/platform/darwin/src/MGLRasterStyleLayer.mm
index 277b2b82a6..94a58409de 100644
--- a/platform/darwin/src/MGLRasterStyleLayer.mm
+++ b/platform/darwin/src/MGLRasterStyleLayer.mm
@@ -39,21 +39,21 @@
 
 #pragma mark - Accessing the Paint Attributes
 
-- (void)setMaximumRasterBrightness:(MGLStyleValue<NSNumber *> *)maximumRasterBrightness {
+- (void)setMaximumRasterBrightness:(NSExpression *)maximumRasterBrightness {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(maximumRasterBrightness);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(maximumRasterBrightness);
     self.rawLayer->setRasterBrightnessMax(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)maximumRasterBrightness {
+- (NSExpression *)maximumRasterBrightness {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getRasterBrightnessMax();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultRasterBrightnessMax());
+        propertyValue = self.rawLayer->getDefaultRasterBrightnessMax();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setMaximumRasterBrightnessTransition:(MGLTransition )transition {
@@ -74,28 +74,28 @@
     return transition;
 }
 
-- (void)setRasterBrightnessMax:(MGLStyleValue<NSNumber *> *)rasterBrightnessMax {
+- (void)setRasterBrightnessMax:(NSExpression *)rasterBrightnessMax {
 }
 
-- (MGLStyleValue<NSNumber *> *)rasterBrightnessMax {
+- (NSExpression *)rasterBrightnessMax {
     return self.maximumRasterBrightness;
 }
 
-- (void)setMinimumRasterBrightness:(MGLStyleValue<NSNumber *> *)minimumRasterBrightness {
+- (void)setMinimumRasterBrightness:(NSExpression *)minimumRasterBrightness {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(minimumRasterBrightness);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(minimumRasterBrightness);
     self.rawLayer->setRasterBrightnessMin(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)minimumRasterBrightness {
+- (NSExpression *)minimumRasterBrightness {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getRasterBrightnessMin();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultRasterBrightnessMin());
+        propertyValue = self.rawLayer->getDefaultRasterBrightnessMin();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setMinimumRasterBrightnessTransition:(MGLTransition )transition {
@@ -116,28 +116,28 @@
     return transition;
 }
 
-- (void)setRasterBrightnessMin:(MGLStyleValue<NSNumber *> *)rasterBrightnessMin {
+- (void)setRasterBrightnessMin:(NSExpression *)rasterBrightnessMin {
 }
 
-- (MGLStyleValue<NSNumber *> *)rasterBrightnessMin {
+- (NSExpression *)rasterBrightnessMin {
     return self.minimumRasterBrightness;
 }
 
-- (void)setRasterContrast:(MGLStyleValue<NSNumber *> *)rasterContrast {
+- (void)setRasterContrast:(NSExpression *)rasterContrast {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(rasterContrast);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(rasterContrast);
     self.rawLayer->setRasterContrast(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)rasterContrast {
+- (NSExpression *)rasterContrast {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getRasterContrast();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultRasterContrast());
+        propertyValue = self.rawLayer->getDefaultRasterContrast();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setRasterContrastTransition:(MGLTransition )transition {
@@ -158,38 +158,38 @@
     return transition;
 }
 
-- (void)setRasterFadeDuration:(MGLStyleValue<NSNumber *> *)rasterFadeDuration {
+- (void)setRasterFadeDuration:(NSExpression *)rasterFadeDuration {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(rasterFadeDuration);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(rasterFadeDuration);
     self.rawLayer->setRasterFadeDuration(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)rasterFadeDuration {
+- (NSExpression *)rasterFadeDuration {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getRasterFadeDuration();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultRasterFadeDuration());
+        propertyValue = self.rawLayer->getDefaultRasterFadeDuration();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setRasterHueRotation:(MGLStyleValue<NSNumber *> *)rasterHueRotation {
+- (void)setRasterHueRotation:(NSExpression *)rasterHueRotation {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(rasterHueRotation);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(rasterHueRotation);
     self.rawLayer->setRasterHueRotate(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)rasterHueRotation {
+- (NSExpression *)rasterHueRotation {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getRasterHueRotate();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultRasterHueRotate());
+        propertyValue = self.rawLayer->getDefaultRasterHueRotate();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setRasterHueRotationTransition:(MGLTransition )transition {
@@ -210,28 +210,28 @@
     return transition;
 }
 
-- (void)setRasterHueRotate:(MGLStyleValue<NSNumber *> *)rasterHueRotate {
+- (void)setRasterHueRotate:(NSExpression *)rasterHueRotate {
 }
 
-- (MGLStyleValue<NSNumber *> *)rasterHueRotate {
+- (NSExpression *)rasterHueRotate {
     return self.rasterHueRotation;
 }
 
-- (void)setRasterOpacity:(MGLStyleValue<NSNumber *> *)rasterOpacity {
+- (void)setRasterOpacity:(NSExpression *)rasterOpacity {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(rasterOpacity);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(rasterOpacity);
     self.rawLayer->setRasterOpacity(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)rasterOpacity {
+- (NSExpression *)rasterOpacity {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getRasterOpacity();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultRasterOpacity());
+        propertyValue = self.rawLayer->getDefaultRasterOpacity();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setRasterOpacityTransition:(MGLTransition )transition {
@@ -252,21 +252,21 @@
     return transition;
 }
 
-- (void)setRasterSaturation:(MGLStyleValue<NSNumber *> *)rasterSaturation {
+- (void)setRasterSaturation:(NSExpression *)rasterSaturation {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(rasterSaturation);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(rasterSaturation);
     self.rawLayer->setRasterSaturation(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)rasterSaturation {
+- (NSExpression *)rasterSaturation {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getRasterSaturation();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultRasterSaturation());
+        propertyValue = self.rawLayer->getDefaultRasterSaturation();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setRasterSaturationTransition:(MGLTransition )transition {
diff --git a/platform/darwin/src/MGLStyle.mm b/platform/darwin/src/MGLStyle.mm
index 5221e838f8..fefd8fcf37 100644
--- a/platform/darwin/src/MGLStyle.mm
+++ b/platform/darwin/src/MGLStyle.mm
@@ -677,70 +677,31 @@ static NSURL *MGLStyleURL_trafficNight;
                 return localizedString;
             };
             
-            if ([layer.text isKindOfClass:[MGLConstantStyleValue class]]) {
-                NSString *textField = [(MGLConstantStyleValue<NSString *> *)layer.text rawValue];
+            if (layer.text.expressionType == NSConstantValueExpressionType) {
+                NSString *textField = layer.text.constantValue;
                 NSString *localizingString = stringByLocalizingString(textField);
                 if (![textField isEqualToString:localizingString]) {
                     MGLTextLanguage *textLanguage = [[MGLTextLanguage alloc] initWithTextLanguage:textField
                                                                                  updatedTextField:localizingString];
                     [self.localizedLayersByIdentifier setObject:@{ textField : textLanguage } forKey:layer.identifier];
-                    layer.text = [MGLStyleValue<NSString *> valueWithRawValue:localizingString];
+                    layer.text = [NSExpression expressionForConstantValue:localizingString];
                 }
             }
-            else if ([layer.text isKindOfClass:[MGLCameraStyleFunction class]]) {
-                MGLCameraStyleFunction *function = (MGLCameraStyleFunction<NSString *> *)layer.text;
-                NSMutableDictionary *stops = function.stops.mutableCopy;
-                NSMutableDictionary *cameraStops = [NSMutableDictionary dictionary];
-                [stops enumerateKeysAndObjectsUsingBlock:^(NSNumber *zoomLevel, MGLConstantStyleValue<NSString *> *stop, BOOL *done) {
-                    NSString *textField = stop.rawValue;
-                    NSString *localizingString = stringByLocalizingString(textField);
-                    if (![textField isEqualToString:localizingString]) {
-                        MGLTextLanguage *textLanguage = [[MGLTextLanguage alloc] initWithTextLanguage:textField
-                                                                                     updatedTextField:localizingString];
-                        [cameraStops setObject:textLanguage forKey:zoomLevel];
-                        stops[zoomLevel] = [MGLStyleValue<NSString *> valueWithRawValue:localizingString];
-                    }
-                    
-                }];
-                if (cameraStops.count > 0) {
-                    [self.localizedLayersByIdentifier setObject:cameraStops forKey:layer.identifier];
-                }
-                function.stops = stops;
-                layer.text = function;
-            }
         }
     } else {
         
         [self.localizedLayersByIdentifier enumerateKeysAndObjectsUsingBlock:^(NSString *identifier, NSDictionary<NSObject *, MGLTextLanguage *> *textFields, BOOL *done) {
             MGLSymbolStyleLayer *layer = (MGLSymbolStyleLayer *)[self.mapView.style layerWithIdentifier:identifier];
             
-            if ([layer.text isKindOfClass:[MGLConstantStyleValue class]]) {
-                NSString *textField = [(MGLConstantStyleValue<NSString *> *)layer.text rawValue];
+            if (layer.text.expressionType == NSConstantValueExpressionType) {
+                NSString *textField = layer.text.constantValue;
                 [textFields enumerateKeysAndObjectsUsingBlock:^(NSObject *originalLanguage, MGLTextLanguage *textLanguage, BOOL *done) {
                     if ([textLanguage.updatedTextField isEqualToString:textField]) {
-                        layer.text = [MGLStyleValue<NSString *> valueWithRawValue:textLanguage.originalTextField];
+                        layer.text = [NSExpression expressionForConstantValue:textLanguage.originalTextField];
                     }
                 }];
 
             }
-            else if ([layer.text isKindOfClass:[MGLCameraStyleFunction class]]) {
-                MGLCameraStyleFunction *function = (MGLCameraStyleFunction<NSString *> *)layer.text;
-                NSMutableDictionary *stops = function.stops.mutableCopy;
-                [textFields enumerateKeysAndObjectsUsingBlock:^(NSObject *zoomKey, MGLTextLanguage *textLanguage, BOOL *done) {
-                    if ([zoomKey isKindOfClass:[NSNumber class]]) {
-                        NSNumber *zoomLevel = (NSNumber*)zoomKey;
-                        MGLConstantStyleValue<NSString *> *stop = [stops objectForKey:zoomLevel];
-                        NSString *textField = stop.rawValue;
-                        if ([textLanguage.updatedTextField isEqualToString:textField]) {
-                            stops[zoomLevel] = [MGLStyleValue<NSString *> valueWithRawValue:textLanguage.originalTextField];
-                        }
-                    }
-                }];
-
-                function.stops = stops;
-                layer.text = function;
-            }
-
         }];
 
         self.localizedLayersByIdentifier = [NSMutableDictionary dictionary];
diff --git a/platform/darwin/src/MGLStyleLayer.h.ejs b/platform/darwin/src/MGLStyleLayer.h.ejs
index df42621c6d..db16df3de5 100644
--- a/platform/darwin/src/MGLStyleLayer.h.ejs
+++ b/platform/darwin/src/MGLStyleLayer.h.ejs
@@ -9,7 +9,6 @@
 // Edit platform/darwin/scripts/generate-style-code.js, then run `make darwin-style-code`.
 
 #import "MGLFoundation.h"
-#import "MGLStyleValue.h"
 #import "MGL<%-
 (type === 'background' ? '' :
  (type === 'raster' ? 'Foreground' :
@@ -120,10 +119,10 @@ which it is added.
 /**
 <%- propertyDoc(property.name, property, type, 'layout').wrap(80, 1) %>
  */
-@property (nonatomic<% if (!property.required) { %>, null_resettable<% } if (property.getter) { %>, getter=<%- objCGetter(property) -%><% } %>) MGLStyleValue<<%- propertyType(property, true) %>> *<%- camelizeWithLeadingLowercase(property.name) %>;
+@property (nonatomic<% if (!property.required) { %>, null_resettable<% } if (property.getter) { %>, getter=<%- objCGetter(property) -%><% } %>) NSExpression *<%- camelizeWithLeadingLowercase(property.name) %>;
 
 <% if (property.original) { %>
-@property (nonatomic<% if (!property.required) { %>, null_resettable<% } %>) MGLStyleValue<<%- propertyType(property, true) %>> *<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> __attribute__((unavailable("Use <%- camelizeWithLeadingLowercase(property.name) %> instead.")));
+@property (nonatomic<% if (!property.required) { %>, null_resettable<% } %>) NSExpression *<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> __attribute__((unavailable("Use <%- camelizeWithLeadingLowercase(property.name) %> instead.")));
 
 <% } -%>
 <% } -%>
@@ -135,7 +134,7 @@ which it is added.
 /**
 <%- propertyDoc(property.name, property, type, 'paint').wrap(80, 1) %>
  */
-@property (nonatomic<% if (!property.required) { %>, null_resettable<% } if (property.getter) { %>, getter=<%- objCGetter(property) -%><% } %>) MGLStyleValue<<%- propertyType(property, true) %>> *<%- camelizeWithLeadingLowercase(property.name) %>;
+@property (nonatomic<% if (!property.required) { %>, null_resettable<% } if (property.getter) { %>, getter=<%- objCGetter(property) -%><% } %>) NSExpression *<%- camelizeWithLeadingLowercase(property.name) %>;
 
 <% if (property["transition"]) { -%>
 /**
@@ -147,7 +146,7 @@ which it is added.
 
 <% } -%>
 <% if (property.original) { -%>
-@property (nonatomic<% if (!property.required) { %>, null_resettable<% } %>) MGLStyleValue<<%- propertyType(property, true) %>> *<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> __attribute__((unavailable("Use <%- camelizeWithLeadingLowercase(property.name) %> instead.")));
+@property (nonatomic<% if (!property.required) { %>, null_resettable<% } %>) NSExpression *<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> __attribute__((unavailable("Use <%- camelizeWithLeadingLowercase(property.name) %> instead.")));
 
 <% } -%>
 <% } -%>
diff --git a/platform/darwin/src/MGLStyleLayer.mm.ejs b/platform/darwin/src/MGLStyleLayer.mm.ejs
index da67cbd633..8101c1f463 100644
--- a/platform/darwin/src/MGLStyleLayer.mm.ejs
+++ b/platform/darwin/src/MGLStyleLayer.mm.ejs
@@ -118,52 +118,32 @@ namespace mbgl {
 #pragma mark - Accessing the Layout Attributes
 
 <% for (const property of layoutProperties) { -%>
-- (void)set<%- camelize(property.name) %>:(MGLStyleValue<<%- propertyType(property, true) %>> *)<%- objCName(property) %> {
+- (void)set<%- camelize(property.name) %>:(NSExpression *)<%- objCName(property) %> {
     MGLAssertStyleLayerIsValid();
 
 <% if (property["property-function"]) { -%>
-    auto mbglValue = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toDataDrivenPropertyValue(<%- objCName(property) %>);
+    auto mbglValue = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<<%- valueTransformerArguments(property)[0] %>>>(<%- objCName(property) %>);
 <% } else { -%>
-<% if (property.type == "enum") { -%>
-    auto mbglValue = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toEnumPropertyValue(<%- objCName(property) %>);
-<% } else if (property.function == "piecewise-constant") { -%>
-    auto mbglValue = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toPropertyValue(<%- objCName(property) %>);
-<% } else { -%>
-    auto mbglValue = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toInterpolatablePropertyValue(<%- objCName(property) %>);
-<% } -%>
+    auto mbglValue = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toPropertyValue<mbgl::style::PropertyValue<<%- valueTransformerArguments(property)[0] %>>>(<%- objCName(property) %>);
 <% } -%>
     self.rawLayer->set<%- camelize(originalPropertyName(property)) %>(mbglValue);
 }
 
-- (MGLStyleValue<<%- propertyType(property, true) %>> *)<%- objCGetter(property) %> {
+- (NSExpression *)<%- objCGetter(property) %> {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->get<%- camelize(originalPropertyName(property)) %>();
-<% if (property["property-function"]) { -%>
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toDataDrivenStyleValue(self.rawLayer->getDefault<%- camelize(originalPropertyName(property)) %>());
+        propertyValue = self.rawLayer->getDefault<%- camelize(originalPropertyName(property)) %>();
     }
-    return MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toDataDrivenStyleValue(propertyValue);
-<% } else { -%>
-<% if (property.type == "enum") { -%>
-    if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<<%- mbglType(property) %>, NSValue *, <%- mbglType(property) %>, MGL<%- camelize(property.name) %>>().toEnumStyleValue(self.rawLayer->getDefault<%- camelize(originalPropertyName(property)) %>());
-    }
-    return MGLStyleValueTransformer<<%- mbglType(property) %>, NSValue *, <%- mbglType(property) %>, MGL<%- camelize(property.name) %>>().toEnumStyleValue(propertyValue);
-<% } else { -%>
-    if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toStyleValue(self.rawLayer->getDefault<%- camelize(originalPropertyName(property)) %>());
-    }
-    return MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toStyleValue(propertyValue);
-<% } -%>
-<% } -%>
+    return MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toExpression(propertyValue);
 }
 
 <% if (property.original) { -%>
-- (void)set<%- camelize(originalPropertyName(property)) %>:(MGLStyleValue<<%- propertyType(property, true) %>> *)<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> {
+- (void)set<%- camelize(originalPropertyName(property)) %>:(NSExpression *)<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> {
 }
 
-- (MGLStyleValue<<%- propertyType(property, true) %>> *)<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> {
+- (NSExpression *)<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> {
     return self.<%- objCGetter(property) %>;
 }
 
@@ -174,45 +154,25 @@ namespace mbgl {
 #pragma mark - Accessing the Paint Attributes
 <% for (const property of paintProperties) { -%>
 
-- (void)set<%- camelize(property.name) %>:(MGLStyleValue<<%- propertyType(property, true) %>> *)<%- objCName(property) %> {
+- (void)set<%- camelize(property.name) %>:(NSExpression *)<%- objCName(property) %> {
     MGLAssertStyleLayerIsValid();
 
 <% if (property["property-function"]) { -%>
-    auto mbglValue = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toDataDrivenPropertyValue(<%- objCName(property) %>);
+    auto mbglValue = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<<%- valueTransformerArguments(property)[0] %>>>(<%- objCName(property) %>);
 <% } else { -%>
-<% if (property.type == "enum") { -%>
-    auto mbglValue = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toEnumPropertyValue(<%- objCName(property) %>);
-<% } else if (property.function == "piecewise-constant") { -%>
-    auto mbglValue = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toPropertyValue(<%- objCName(property) %>);
-<% } else { -%>
-    auto mbglValue = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toInterpolatablePropertyValue(<%- objCName(property) %>);
-<% } -%>
+    auto mbglValue = MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toPropertyValue<mbgl::style::PropertyValue<<%- valueTransformerArguments(property)[0] %>>>(<%- objCName(property) %>);
 <% } -%>
     self.rawLayer->set<%- camelize(originalPropertyName(property)) %>(mbglValue);
 }
 
-- (MGLStyleValue<<%- propertyType(property, true) %>> *)<%- objCGetter(property) %> {
+- (NSExpression *)<%- objCGetter(property) %> {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->get<%- camelize(originalPropertyName(property)) %>();
-<% if (property["property-function"]) { -%>
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toDataDrivenStyleValue(self.rawLayer->getDefault<%- camelize(originalPropertyName(property)) %>());
+        propertyValue = self.rawLayer->getDefault<%- camelize(originalPropertyName(property)) %>();
     }
-    return MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toDataDrivenStyleValue(propertyValue);
-<% } else { -%>
-<% if (property.type == "enum") { -%>
-    if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<<%- mbglType(property) %>, NSValue *, <%- mbglType(property) %>, MGL<%- camelize(property.name) %>>().toEnumStyleValue(self.rawLayer->getDefault<%- camelize(originalPropertyName(property)) %>());
-    }
-    return MGLStyleValueTransformer<<%- mbglType(property) %>, NSValue *, <%- mbglType(property) %>, MGL<%- camelize(property.name) %>>().toEnumStyleValue(propertyValue);
-<% } else { -%>
-    if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toStyleValue(self.rawLayer->getDefault<%- camelize(originalPropertyName(property)) %>());
-    }
-    return MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toStyleValue(propertyValue);
-<% } -%>
-<% } -%>
+    return MGLStyleValueTransformer<<%- valueTransformerArguments(property).join(', ') %>>().toExpression(propertyValue);
 }
 <% if (property["transition"]) { -%>
 
@@ -236,10 +196,10 @@ namespace mbgl {
 <% } -%>
 <% if (property.original) { -%>
 
-- (void)set<%- camelize(originalPropertyName(property)) %>:(MGLStyleValue<<%- propertyType(property, true) %>> *)<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> {
+- (void)set<%- camelize(originalPropertyName(property)) %>:(NSExpression *)<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> {
 }
 
-- (MGLStyleValue<<%- propertyType(property, true) %>> *)<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> {
+- (NSExpression *)<%- camelizeWithLeadingLowercase(originalPropertyName(property)) %> {
     return self.<%- objCGetter(property) %>;
 }
 <% } -%>
diff --git a/platform/darwin/src/MGLStyleValue.h b/platform/darwin/src/MGLStyleValue.h
index 9c9b1dc4d1..f6e9c51729 100644
--- a/platform/darwin/src/MGLStyleValue.h
+++ b/platform/darwin/src/MGLStyleValue.h
@@ -6,485 +6,43 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
-/**
- Options for `MGLStyleFunction` objects.
- */
-typedef NSString *MGLStyleFunctionOption NS_STRING_ENUM;
+typedef NSString *MGLStyleFunctionOption NS_STRING_ENUM NS_UNAVAILABLE;
 
-/**
- An `NSNumber` object containing an integer that determines the style function's 
- exponential interpolation base.
- 
- The exponential interpolation base controls the rate at which the function’s 
- output values increase. A value of 1 causes the function to increase linearly 
- based on zoom level or attribute value. A higher exponential interpolation base
- causes the function’s output values to vary exponentially, increasing more rapidly
- towards the high end of the function’s range. The default value of this property 
- is 1, for a linear curve.
+extern MGL_EXPORT const MGLStyleFunctionOption MGLStyleFunctionOptionInterpolationBase __attribute__((unavailable("Use NSExpression instead, applying the mgl_interpolateWithCurveType:parameters:stops: function with a curve type of “exponential” and a non-nil parameter.")));
 
- This attribute corresponds to the
- <a href="https://www.mapbox.com/mapbox-gl-js/style-spec/#function-base"><code>base</code></a>
- function property in the Mapbox Style Specification.
+extern MGL_EXPORT const MGLStyleFunctionOption MGLStyleFunctionOptionDefaultValue __attribute__((unavailable("Use +[NSExpression expressionForConditional:trueExpression:falseExpression:] instead.")));
 
- This option only applies to functions that use an 
- `MGLInterpolationModeExponential` interpolation mode that are assigned to
- interpolatable style layer properties.
- */
-extern MGL_EXPORT const MGLStyleFunctionOption MGLStyleFunctionOptionInterpolationBase;
-
-/**
- An `MGLConstantStyleValue` object that specifies a default value that a style
- function can use when it can't otherwise determine a value.
-
- A default value can be used to set the value of a style layer property that
- is not otherwise set by a function. For example, a source function with a
- `MGLInterpolationModeCategorical` interpolation mode with stops that specify
- color values to use based on a feature's attributes would set any feature
- that does not have attributes that match the stop key values to this 
- default value.
- 
- This option only applies to `MGLSourceStyleFunction` and
- `MGLCompositeStyleFunction` functions.
- */
-extern MGL_EXPORT const MGLStyleFunctionOption MGLStyleFunctionOptionDefaultValue;
-
-/** 
- The modes used to interpolate property values between map zoom level changes
- or over a range of feature attribute values.
- */
 typedef NS_ENUM(NSUInteger, MGLInterpolationMode) {
-    /**
-     Values between two stops are interpolated linearly, or exponentially based on 
-     the `MGLStyleFunctionOptionInterpolationBase`. A higher interpolation base 
-     causes the function’s output values to vary exponentially, increasing more rapidly
-     towards the high end of the function’s range. The default interpolation base of 1 
-     creates a linear interpolation. Use exponential interpolation mode to show values
-     relative to stop keys.
-     */
-    MGLInterpolationModeExponential = 0,
-    /**
-     Values between two stops are not interpolated. Instead, properties are set
-     to the value of the stop just less than the function input. Use interval
-     interpolation mode to show values that fall within a range.
-     */
-    MGLInterpolationModeInterval,
-    /**
-     Values between two stops are not interpolated. Instead, properties are set
-     to the value of the stop equal to the function input's key value. Use
-     categorical interpolation mode to show values that fit into categories.
-     */
-    MGLInterpolationModeCategorical,
-    /**
-     Values between two stops are not interpolated. Instead, for any given feature, the
-     style value matches a value in that feature’s attributes dictionary. Use identity
-     interpolation mode to show attribute values that can be used as style values.
-     */
-    MGLInterpolationModeIdentity
-};
-
-/**
- An `MGLStyleValue` object is a generic container for a style attribute value.
- The layout and paint attribute properties of `MGLStyleLayer` can be set to
- `MGLStyleValue` objects.
-
- The `MGLStyleValue` class itself represents a class cluster. Under the hood, a
- particular `MGLStyleValue` object may be either an `MGLConstantStyleValue` to
- represent a constant value or one of the concrete subclasses of 
- `MGLStyleFunction` to represent a value function. Do not initialize an 
- `MGLStyleValue` object directly; instead, use one of the class factory methods 
- to create an `MGLStyleValue` object.
+    MGLInterpolationModeExponential __attribute__((unavailable("Use NSExpression instead, applying the mgl_interpolateWithCurveType:parameters:stops: function with a curve type of “exponential”."))) = 0,
+    MGLInterpolationModeInterval __attribute__((unavailable("Use NSExpression instead, calling the mgl_stepWithMinimum:stops: function."))),
+    MGLInterpolationModeCategorical __attribute__((unavailable("Use NSExpression instead."))),
+    MGLInterpolationModeIdentity __attribute__((unavailable("Use +[NSExpression expressionForKeyPath:] instead.")))
+} __attribute__((unavailable("Use NSExpression instead.")));
 
- The `MGLStyleValue` class takes a generic parameter `T` that indicates the
- Foundation class being wrapped by this class. Common values for `T` include:
-
- <ul>
- <li><code>NSNumber</code> (for Boolean values and floating-point numbers)</li>
- <li><code>NSValue</code> (for <code>CGVector</code>, <code>NSEdgeInsets</code>, <code>UIEdgeInsets</code>, and enumerations)</li>
- <li><code>NSString</code></li>
- <li><code>NSColor</code> or <code>UIColor</code></li>
- <li><code>NSArray</code></li>
- </ul>
- */
-MGL_EXPORT
+MGL_EXPORT __attribute__((unavailable("Use NSExpression instead.")))
 @interface MGLStyleValue<T> : NSObject
-
-#pragma mark Creating a Style Value
-
-/**
- Creates and returns an `MGLConstantStyleValue` object containing a raw value.
-
- @param rawValue The constant value contained by the object.
- @return An `MGLConstantStyleValue` object containing `rawValue`, which is
-    treated as a constant value.
- */
-+ (instancetype)valueWithRawValue:(T)rawValue;
-
-#pragma mark Function values
-
-/**
- Creates and returns an `MGLCameraStyleFunction` object representing a linear camera
- function with one or more stops.
-
- @param stops A dictionary associating zoom levels with style values.
- @return An `MGLCameraStyleFunction` object with the given stops.
- */
-+ (instancetype)valueWithStops:(NS_DICTIONARY_OF(NSNumber *, MGLStyleValue<T> *) *)stops __attribute__((deprecated("Use +[MGLStyleValue valueWithInterpolationMode:cameraStops:options:]")));
-
-/**
- Creates and returns an `MGLCameraStyleFunction` object representing a camera
- function with an exponential interpolation base and one or more stops.
-
- @param interpolationBase The exponential base of the interpolation curve.
- @param stops A dictionary associating zoom levels with style values.
- @return An `MGLCameraStyleFunction` object with the given interpolation base and stops.
- */
-+ (instancetype)valueWithInterpolationBase:(CGFloat)interpolationBase stops:(NS_DICTIONARY_OF(NSNumber *, MGLStyleValue<T> *) *)stops __attribute__((deprecated("Use +[MGLStyleValue valueWithInterpolationMode:cameraStops:options:]")));
-
-/**
- Creates and returns an `MGLCameraStyleFunction` object representing a camera function
- with one or more stops.
-
- @param interpolationMode The mode used to interpolate property values between 
-    map zoom level changes.
- @param cameraStops A dictionary associating zoom levels with style values.
- @param options A dictionary containing `MGLStyleFunctionOption` values that 
-    specify how a function is applied.
- @return An `MGLCameraStyleFunction` object with the given interpolation mode,
-    camera stops, and options.
- */
-+ (instancetype)valueWithInterpolationMode:(MGLInterpolationMode)interpolationMode cameraStops:(NS_DICTIONARY_OF(id, MGLStyleValue<T> *) *)cameraStops options:(nullable NS_DICTIONARY_OF(MGLStyleFunctionOption, id) *)options;
-
-/**
- Creates and returns an `MGLSourceStyleFunction` object representing a source function.
-
- @param interpolationMode The mode used to interpolate property values over a 
-    range of feature attribute values.
- @param sourceStops A dictionary associating feature attributes with style values.
- @param attributeName Specifies the feature attribute to take as the function 
-    input.
- @param options A dictionary containing `MGLStyleFunctionOption` values that
-    specify how a function is applied.
- @return An `MGLSourceStyleFunction` object with the given interpolation mode,
-    source stops, attribute name, and options.
- */
-+ (instancetype)valueWithInterpolationMode:(MGLInterpolationMode)interpolationMode sourceStops:(nullable NS_DICTIONARY_OF(id, MGLStyleValue<T> *) *)sourceStops attributeName:(NSString *)attributeName options:(nullable NS_DICTIONARY_OF(MGLStyleFunctionOption, id) *)options;
-
-/**
- Creates and returns an `MGLCompositeStyleFunction` object representing a composite
- function.
-
- @param interpolationMode The mode used to interpolate property values over a 
-    range of feature attribute values for each outer zoom level.
- @param compositeStops A dictionary associating feature attributes with style
-    values.
- @param attributeName Specifies the feature attribute to take as the function
-    input.
- @param options A dictionary containing `MGLStyleFunctionOption` values that
-    specify how a function is applied.
- @return An `MGLCompositeStyleFunction` object with the given interpolation mode,
-    composite stops, attribute name, and options.
- */
-+ (instancetype)valueWithInterpolationMode:(MGLInterpolationMode)interpolationMode compositeStops:(NS_DICTIONARY_OF(id, NS_DICTIONARY_OF(id, MGLStyleValue<T> *) *) *)compositeStops attributeName:(NSString *)attributeName options:(nullable NS_DICTIONARY_OF(MGLStyleFunctionOption, id) *)options;
-
 @end
 
-/**
- An `MGLConstantStyleValue` object is a generic container for a style attribute
- value that remains constant as the zoom level changes. The layout and paint
- attribute properties of `MGLStyleLayer` objects can be set to
- `MGLConstantStyleValue` objects.
-
- The `MGLConstantStyleValue` class takes a generic parameter `T` that indicates
- the Foundation class being wrapped by this class.
- */
-MGL_EXPORT
+MGL_EXPORT __attribute__((unavailable("Use +[NSExpression expressionForConstantValue:] instead.")))
 @interface MGLConstantStyleValue<T> : MGLStyleValue<T>
-
-#pragma mark Creating a Style Constant Value
-
-/**
- Creates and returns an `MGLConstantStyleValue` object containing a raw value.
-
- @param rawValue The constant value contained by the object.
- @return An `MGLConstantStyleValue` object containing `rawValue`, which is
-    treated as a constant value.
- */
-+ (instancetype)valueWithRawValue:(T)rawValue;
-
-#pragma mark Initializing a Style Constant Value
-
-- (instancetype)init NS_UNAVAILABLE;
-
-/**
- Returns an `MGLConstantStyleValue` object containing a raw value.
-
- @param rawValue The value contained by the receiver.
- @return An `MGLConstantStyleValue` object containing `rawValue`.
- */
-- (instancetype)initWithRawValue:(T)rawValue NS_DESIGNATED_INITIALIZER;
-
-#pragma mark Accessing the Underlying Value
-
-/**
- The raw value contained by the receiver.
- */
-@property (nonatomic) T rawValue;
-
 @end
 
 @compatibility_alias MGLStyleConstantValue MGLConstantStyleValue;
 
-/**
- An `MGLStyleFunction` is a is an abstract superclass for functions that are 
- defined by an `MGLCameraStyleFunction`, `MGLSourceStyleFunction`, or
- `MGLCompositeStyleFunction` object.
- 
- Create instances of `MGLCameraStyleFunction`, `MGLSourceStyleFunction`, and
- `MGLCompositeStyleFunction` in order to use `MGLStyleFunction`'s methods. Do
- not create instances of `MGLStyleFunction` directly, and do not create your
- own subclasses of this class.
-
- The `MGLStyleFunction` class takes a generic parameter `T` that indicates the
- Foundation class being wrapped by this class.
- */
-MGL_EXPORT
+MGL_EXPORT __attribute__((unavailable("Use NSExpression instead, calling the mgl_stepWithMinimum:stops: or mgl_interpolateWithCurveType:parameters:stops: function.")))
 @interface MGLStyleFunction<T> : MGLStyleValue<T>
-
-#pragma mark Creating a Style Function
-
-/**
- Creates and returns an `MGLCameraStyleFunction` object representing a camera 
- function with a linear interpolation curve.
-
- @note Do not create function instances using this method unless it is required 
-    for backwards compatiblity with your application code.
-
- @param stops A dictionary associating zoom levels with style values.
- @return An `MGLCameraStyleFunction` object with the given stops.
- */
-+ (instancetype)functionWithStops:(NS_DICTIONARY_OF(NSNumber *, MGLStyleValue<T> *) *)stops __attribute__((deprecated("Use +[MGLStyleValue valueWithInterpolationMode:cameraStops:options:]")));
-
-/**
- Creates and returns an `MGLCameraStyleFunction` object representing a camera
- function with an interpolation curve controlled by the provided interpolation 
- base.
-
- @note Do not create function instances using this method unless it is required
-    for backwards compatiblity with your application code.
-
- @param interpolationBase The exponential base of the interpolation curve.
- @param stops A dictionary associating zoom levels with style values.
- @return An `MGLCameraStyleFunction` object with the given interpolation base and stops.
- */
-+ (instancetype)functionWithInterpolationBase:(CGFloat)interpolationBase stops:(NS_DICTIONARY_OF(NSNumber *, MGLStyleValue<T> *) *)stops __attribute__((deprecated("Use +[MGLStyleValue valueWithInterpolationMode:cameraStops:options:]")));
-
-#pragma mark Initializing a Style Function
-
-/**
- Returns an `MGLStyleFunction` object representing a camera function. If the 
- function is set as a style layer property value, it will be interpreted
- as a camera function with an interpolation curve controlled by the provided
- interpolation base.
- 
- @note Do not create instances of `MGLStyleFunction` unless it is required for
-    backwards compatiblity with your application code. You should create and use
-    instances of `MGLCameraStyleFunction` to specify how properties will
-    be visualized at different zoom levels.
-
- @param interpolationBase The exponential base of the interpolation curve.
- @param stops A dictionary associating zoom levels with style values.
- @return An `MGLStyleFunction` object with the given interpolation base and stops.
- */
-- (instancetype)initWithInterpolationBase:(CGFloat)interpolationBase stops:(NS_DICTIONARY_OF(NSNumber *, MGLStyleValue<T> *) *)stops __attribute__((deprecated("Use +[MGLStyleValue valueWithInterpolationMode:cameraStops:options:]")));
-
-#pragma mark Accessing the Parameters of a Function
-
-/**
- The modes used to interpolate property values between map zoom level changes or
- over a range of feature attribute values.
- */
-@property (nonatomic) MGLInterpolationMode interpolationMode;
-
-/**
- A dictionary associating zoom levels with style values.
- */
-@property (nonatomic, copy, nullable) NSDictionary *stops;
-
-/**
- The exponential interpolation base of the function’s interpolation curve.
- 
- @note This property specifies the exponential base of the interpolation curve 
-    of `MGLCameraStyleFunction` and `MGLSourceStyleFunction` functions that use 
-    a `MGLInterpolationModeExponential` `interpolationMode`. Otherwise, it is
-    ignored.
- */
-@property (nonatomic) CGFloat interpolationBase;
-
 @end
 
-/**
- An `MGLCameraStyleFunction` is a value function defining a style value that changes
- as the zoom level changes. The layout and paint attribute properties of an
- `MGLStyleLayer` object can be set to `MGLCameraStyleFunction` objects. Use a camera
- function to create the illusion of depth and control data density.
-
- The `MGLCameraStyleFunction` class takes a generic parameter `T` that indicates the
- Foundation class being wrapped by this class.
- */
-MGL_EXPORT
+MGL_EXPORT __attribute__((unavailable("Use NSExpression instead, applying the mgl_stepWithMinimum:stops: or mgl_interpolateWithCurveType:parameters:stops: function to the $zoomLevel variable.")))
 @interface MGLCameraStyleFunction<T> : MGLStyleFunction<T>
-
-#pragma mark Creating a Camera Function
-
-/**
- Creates and returns an `MGLCameraStyleFunction` object representing a camera
- function with one or more stops.
-
- @param interpolationMode The mode used to interpolate property values between
-    map zoom level changes.
- @param stops A dictionary associating zoom levels with style values.
- @param options A dictionary containing `MGLStyleFunctionOption` values that
-    specify how a function is applied.
- @return An `MGLCameraStyleFunction` object with the given interpolation mode,
-    camera stops, and options.
- */
-+ (instancetype)functionWithInterpolationMode:(MGLInterpolationMode)interpolationMode stops:(NS_DICTIONARY_OF(id, MGLStyleValue<T> *) *)stops options:(nullable NS_DICTIONARY_OF(MGLStyleFunctionOption, id) *)options;
-
-#pragma mark Accessing the Parameters of a Camera Function
-
-/**
- A dictionary associating zoom levels with style values.
-
- Each of the function’s stops is represented by one key-value pair in the
- dictionary. Each key in the dictionary is an `NSNumber` object containing a
- floating-point zoom level. Each value in the dictionary is an `MGLStyleValue`
- object containing the value of the style attribute when the map is at the
- associated zoom level. An `MGLStyleFunction` object may not be used recursively
- as a stop value.
- */
-@property (nonatomic, copy) NS_DICTIONARY_OF(id, MGLStyleValue<T> *) *stops;
-
 @end
 
-/**
- An `MGLSourceStyleFunction` is a value function defining a style value that 
- changes with its properties. The layout and paint attribute properties of an
- `MGLStyleLayer` object can be set to `MGLSourceStyleFunction` objects.
- Use source functions to visually differentate types of features within the same 
- layer or create data visualizations.
-
- The `MGLSourceStyleFunction` class takes a generic parameter `T` that indicates the
- Foundation class being wrapped by this class.
- */
-MGL_EXPORT
+MGL_EXPORT __attribute__((unavailable("Use NSExpression instead, applying the mgl_stepWithMinimum:stops: or mgl_interpolateWithCurveType:parameters:stops: function to a key path expression.")))
 @interface MGLSourceStyleFunction<T> : MGLStyleFunction<T>
-
-#pragma mark Creating a Source Function
-
-/**
- Creates and returns an `MGLSourceStyleFunction` object representing a source 
- function.
-
- @param interpolationMode The mode used to interpolate property values over a
-    range of feature attribute values.
- @param stops A dictionary associating feature attributes with style values.
- @param attributeName Specifies the feature attribute to take as the function
-    input.
- @param options A dictionary containing `MGLStyleFunctionOption` values that
-    specify how a function is applied.
- @return An `MGLSourceStyleFunction` object with the given interpolation mode,
-    source stops, attribute name, and options.
-*/
-+ (instancetype)functionWithInterpolationMode:(MGLInterpolationMode)interpolationMode stops:(nullable NS_DICTIONARY_OF(id, MGLStyleValue<T> *) *)stops attributeName:(NSString *)attributeName options:(nullable NS_DICTIONARY_OF(MGLStyleFunctionOption, id) *)options;
-
-#pragma mark Accessing the Parameters of a Source Function
-
-/**
- A string that specifies the feature attribute key whose value be used as the function
- input.
-*/
-@property (nonatomic, copy) NSString *attributeName;
-
-/**
- A dictionary associating attribute values with style values.
-
- Each of the function’s stops is represented by one key-value pair in the
- dictionary. Each key in the dictionary is an object representing a feature 
- attribute key or interpolation stop. Each value in the dictionary is an 
- `MGLStyleValue` object containing the value to use when the function is given 
- the associated attribute key. An `MGLStyleFunction` object may not be used 
- recursively as a stop value.
- */
-@property (nonatomic, copy, nullable) NS_DICTIONARY_OF(id, MGLStyleValue<T> *) *stops;
-
-/**
- An `MGLStyleValue` object containing the default value to use when there is
- no input to provide to the function.
- */
-@property (nonatomic, nullable) MGLStyleValue<T> *defaultValue;
-
 @end
 
-/**
- An `MGLCompositeStyleFunction` is a value function defining a style value that
- changes with the feature attributes at each map zoom level. The layout and paint 
- attribute properties of an `MGLStyleLayer` object can be set to 
- `MGLCompositeStyleFunction` objects. Use composite functions to allow the 
- appearance of a map feature to change with both its attributes and the map zoom 
- level.
-
- The `MGLCompositeStyleFunction` class takes a generic parameter `T` that indicates the
- Foundation class being wrapped by this class.
- */
-MGL_EXPORT
+MGL_EXPORT __attribute__((unavailable("Use a NSExpression instead with nested mgl_stepWithMinimum:stops: or mgl_interpolateWithCurveType:parameters:stops: function calls.")))
 @interface MGLCompositeStyleFunction<T> : MGLStyleFunction<T>
-
-#pragma mark Creating a Composite Function
-
-/**
- Creates and returns an `MGLCompositeStyleFunction` object representing a composite
- function.
-
- @param interpolationMode The mode used to interpolate property values over a
-    range of feature attribute values for each outer zoom level.
- @param stops A dictionary associating feature attributes with style values.
- @param attributeName Specifies the feature attribute to take as the function
-    input.
- @param options A dictionary containing `MGLStyleFunctionOption` values that
-    specify how a function is applied.
- @return An `MGLCompositeStyleFunction` object with the given interpolation mode,
-    composite stops, attribute name, and options.
- */
-+ (instancetype)functionWithInterpolationMode:(MGLInterpolationMode)interpolationMode stops:(NS_DICTIONARY_OF(id, NS_DICTIONARY_OF(id, MGLStyleValue<T> *) *) *)stops attributeName:(NSString *)attributeName options:(nullable NS_DICTIONARY_OF(MGLStyleFunctionOption, id) *)options;
-
-#pragma mark Accessing the Parameters of a Composite Function
-
-/**
- A string that specifies the feature attribute key whose value be used as the function
- input.
- */
-@property (nonatomic, copy) NSString *attributeName;
-
-/**
- A dictionary associating attribute values with style values.
-
- Each of the function’s stops is represented by one key-value pair in the
- dictionary. Each key in the dictionary is an `NSNumber` object containing a
- floating-point zoom level. Each value in the dictionary is an inner nested 
- dictionary. Each key in the nested dictionary is an object representing a feature
- attribute key or interpolation stop. Each value in the nested dictionary is an
- `MGLStyleValue` object containing the value to use when the function is given
- the associated attribute key. An `MGLStyleFunction` object may not be used
- recursively as a value inside the nested dictionary.
- */
-@property (nonatomic, copy) NS_DICTIONARY_OF(id, NS_DICTIONARY_OF(id, MGLStyleValue<T> *) *) *stops;
-
-/**
- An `MGLStyleValue` object containing the default value to use when there is
- no input to provide to the function.
- */
-@property (nonatomic, nullable) MGLStyleValue<T> *defaultValue;
-
 @end
 
 NS_ASSUME_NONNULL_END
diff --git a/platform/darwin/src/MGLStyleValue.mm b/platform/darwin/src/MGLStyleValue.mm
index 4dd6b550d8..74e1926f79 100644
--- a/platform/darwin/src/MGLStyleValue.mm
+++ b/platform/darwin/src/MGLStyleValue.mm
@@ -1,308 +1,121 @@
 #import "MGLStyleValue_Private.h"
 
+#include <mbgl/style/expression/expression.hpp>
+
 const MGLStyleFunctionOption MGLStyleFunctionOptionInterpolationBase = @"MGLStyleFunctionOptionInterpolationBase";
 const MGLStyleFunctionOption MGLStyleFunctionOptionDefaultValue = @"MGLStyleFunctionOptionDefaultValue";
 
-@implementation MGLStyleValue
-
-+ (instancetype)valueWithRawValue:(id)rawValue {
-    return [MGLConstantStyleValue valueWithRawValue:rawValue];
-}
-
-+ (instancetype)valueWithInterpolationBase:(CGFloat)interpolationBase stops:(NSDictionary *)stops {
-    return [MGLCameraStyleFunction functionWithInterpolationMode:MGLInterpolationModeExponential stops:stops options:@{MGLStyleFunctionOptionInterpolationBase: @(interpolationBase)}];
-}
-
-+ (instancetype)valueWithStops:(NSDictionary *)stops {
-    return [MGLCameraStyleFunction functionWithInterpolationMode:MGLInterpolationModeExponential stops:stops options:nil];
-}
-
-+ (instancetype)valueWithInterpolationMode:(MGLInterpolationMode)interpolationMode cameraStops:(NSDictionary *)cameraStops options:(NSDictionary *)options {
-    return [MGLCameraStyleFunction functionWithInterpolationMode:interpolationMode stops:cameraStops options:options];
-}
-
-+ (instancetype)valueWithInterpolationMode:(MGLInterpolationMode)interpolationMode sourceStops:(NSDictionary *)sourceStops attributeName:(NSString *)attributeName options:(NSDictionary *)options {
-    return [MGLSourceStyleFunction functionWithInterpolationMode:interpolationMode stops:sourceStops attributeName:attributeName options:options];
-}
-
-+ (instancetype)valueWithInterpolationMode:(MGLInterpolationMode)interpolationMode compositeStops:(NSDictionary *)compositeStops attributeName:(NSString *)attributeName options:(NSDictionary *)options {
-    return [MGLCompositeStyleFunction functionWithInterpolationMode:interpolationMode stops:compositeStops attributeName:attributeName options:options];
-}
-
-@end
-
-@implementation MGLConstantStyleValue
-
-+ (instancetype)valueWithRawValue:(id)rawValue {
-    return [[self alloc] initWithRawValue:rawValue];
+id MGLJSONObjectFromMBGLValue(const mbgl::style::expression::Value &value) {
+    return value.match([](const mbgl::NullValue) -> id {
+        return [NSNull null];
+    }, [](const bool value) {
+        return @(value);
+    }, [](const float value) {
+        return @(value);
+    }, [](const int64_t value) {
+        return @(value);
+    }, [](const double value) {
+        return @(value);
+    }, [](const std::string &value) {
+        return @(value.c_str());
+    }, [](const mbgl::Color &value) {
+        return [MGLColor mgl_colorWithColor:value];
+    }, [](const mbgl::style::Position &value) {
+        std::array<float, 3> spherical = value.getSpherical();
+        MGLSphericalPosition position = MGLSphericalPositionMake(spherical[0], spherical[1], spherical[2]);
+        return [NSValue valueWithMGLSphericalPosition:position];
+    }, [&](const std::vector<mbgl::style::expression::Value> &vector) {
+        NSMutableArray *array = [NSMutableArray arrayWithCapacity:vector.size()];
+        for (auto value : vector) {
+            [array addObject:MGLJSONObjectFromMBGLValue(value)];
+        }
+        return @[@"literal", array];
+    }, [&](const std::unordered_map<std::string, mbgl::style::expression::Value> &map) {
+        NSMutableDictionary *dictionary = [NSMutableDictionary dictionaryWithCapacity:map.size()];
+        for (auto &item : map) {
+            dictionary[@(item.first.c_str())] = MGLJSONObjectFromMBGLValue(item.second);
+        }
+        return @[@"literal", dictionary];
+    }, [](const auto &) -> id {
+        return nil;
+    });
 }
 
-- (instancetype)initWithRawValue:(id)rawValue {
-    if (self = [super init]) {
-        _rawValue = rawValue;
+id MGLJSONObjectFromMBGLExpression(const mbgl::style::expression::Expression &mbglExpression) {
+    using namespace mbgl::style::expression;
+    if (auto literalExpression = dynamic_cast<const Literal *>(&mbglExpression)) {
+        auto result = literalExpression->evaluate({ nullptr });
+        return result ? MGLJSONObjectFromMBGLValue(*result) : nil;
     }
-    return self;
-}
-
-- (NSString *)description {
-    return [self.rawValue description];
-}
-
-- (NSString *)debugDescription {
-    return [self.rawValue debugDescription];
-}
-
-- (BOOL)isEqual:(MGLConstantStyleValue *)other {
-    return [other isKindOfClass:[self class]] && [other.rawValue isEqual:self.rawValue];
-}
-
-- (NSUInteger)hash {
-    return [self.rawValue hash];
-}
-
-@end
-
-@implementation MGLStyleFunction
-
-+ (instancetype)functionWithStops:(NSDictionary *)stops {
-    return [MGLCameraStyleFunction functionWithInterpolationMode:MGLInterpolationModeExponential stops:stops options:nil];
-}
-
-+ (instancetype)functionWithInterpolationBase:(CGFloat)interpolationBase stops:(NSDictionary *)stops {
-    return [MGLCameraStyleFunction functionWithInterpolationMode:MGLInterpolationModeExponential stops:stops options:@{MGLStyleFunctionOptionInterpolationBase: @(interpolationBase)}];
-}
-
-- (instancetype)init {
-    if (self = [super init]) {
-        self.interpolationBase = 1.0;
-        self.stops = @{};
+    if (auto assertExpression = dynamic_cast<const ArrayAssertion *>(&mbglExpression)) {
+        NSMutableArray *inputs = [NSMutableArray array];
+        assertExpression->eachChild([&](const Expression &child) {
+            [inputs addObject:MGLJSONObjectFromMBGLExpression(child)];
+        });
+        return @[@"literal", inputs.lastObject];
     }
-    return self;
-}
-
-- (instancetype)initWithInterpolationBase:(CGFloat)interpolationBase stops:(NSDictionary *)stops {
-    if (self = [super init]) {
-        self.interpolationBase = interpolationBase;
-        self.stops = stops;
+    if (auto assertExpression = dynamic_cast<const Assertion *>(&mbglExpression)) {
+        NSMutableArray *inputs = [NSMutableArray array];
+        assertExpression->eachChild([&](const Expression &child) {
+            [inputs addObject:MGLJSONObjectFromMBGLExpression(child)];
+        });
+        return inputs.firstObject;
     }
-    return self;
-}
-
-- (NSString *)description {
-    return [NSString stringWithFormat:@"<%@: %p, \
-            stops = %@, \
-            interpolationBase = %f>",
-            NSStringFromClass([self class]), (void *)self,
-            self.stops,
-            self.interpolationBase];
-}
-
-- (BOOL)isEqual:(MGLStyleFunction *)other {
-    return ([other isKindOfClass:[self class]]
-            && [other.stops isEqualToDictionary:self.stops]
-            && other.interpolationBase == self.interpolationBase);
-}
-
-- (NSUInteger)hash {
-    return  self.stops.hash + @(self.interpolationBase).hash;
-}
-
-@end
-
-@implementation MGLCameraStyleFunction
-
-@dynamic stops;
-
-+ (instancetype)functionWithInterpolationMode:(MGLInterpolationMode)interpolationMode stops:(NSDictionary *)stops options:(NSDictionary *)options {
-    return [[self alloc] initWithInterpolationMode:interpolationMode stops:stops options:options];
-}
-
-- (instancetype)initWithInterpolationBase:(CGFloat)interpolationBase stops:(NSDictionary *)stops {
-    return [self initWithInterpolationMode:MGLInterpolationModeExponential stops:stops options:@{MGLStyleFunctionOptionInterpolationBase: @(interpolationBase)}];
-}
-
-- (instancetype)initWithInterpolationMode:(MGLInterpolationMode)interpolationMode stops:(NSDictionary *)stops options:(NSDictionary *)options {
-    if (![stops count]) {
-        [NSException raise:NSInvalidArgumentException
-                    format:@"Camera functions must have at least one stop."];
-        return {};
+    if (auto compoundExpression = dynamic_cast<const CompoundExpressionBase *>(&mbglExpression)) {
+        const std::string name = compoundExpression->getName();
+        mbgl::optional<std::size_t> parameterCount = compoundExpression->getParameterCount();
+        NSMutableArray *expressionObject = parameterCount ? [NSMutableArray arrayWithCapacity:*parameterCount + 1] : [NSMutableArray array];
+        [expressionObject addObject:@(name.c_str())];
+        compoundExpression->eachChild([&](const Expression &child) {
+            [expressionObject addObject:MGLJSONObjectFromMBGLExpression(child)];
+        });
+        return expressionObject;
     }
-
-    if (self = [super init]) {
-        self.interpolationMode = interpolationMode;
-        self.stops = stops;
-
-        if ([options.allKeys containsObject:MGLStyleFunctionOptionInterpolationBase]) {
-            if ([options[MGLStyleFunctionOptionInterpolationBase] isKindOfClass:[NSNumber class]]) {
-                NSNumber *value = (NSNumber *)options[MGLStyleFunctionOptionInterpolationBase];
-                self.interpolationBase = [value floatValue];
-            } else {
-                [NSException raise:NSInvalidArgumentException format:@"Interpolation base must be an NSNumber that represents a CGFloat."];
-            }
+    if (auto stepExpression = dynamic_cast<const Step *>(&mbglExpression)) {
+        auto &input = stepExpression->getInput();
+        NSMutableArray *expressionObject = [NSMutableArray arrayWithObjects:@"step", MGLJSONObjectFromMBGLExpression(*input.get()), nil];
+        stepExpression->eachStop([&](double stop, const Expression &child) {
+            [expressionObject addObject:@(stop)];
+            [expressionObject addObject:MGLJSONObjectFromMBGLExpression(child)];
+        });
+        if ([expressionObject[2] isEqual:@(-INFINITY)]) {
+            [expressionObject removeObjectAtIndex:2];
         }
+        return expressionObject;
     }
-    return self;
-}
-
-- (NSString *)description {
-    return [NSString stringWithFormat:@"<%@: %p, \
-            interpolationMode = %lu, \
-            stops = %@, \
-            interpolationBase = %f>",
-            NSStringFromClass([self class]), (void *)self,
-            (unsigned long)self.interpolationMode,
-            self.stops,
-            self.interpolationBase];
-}
-
-- (BOOL)isEqual:(MGLCameraStyleFunction *)other {
-    return ([other isKindOfClass:[self class]]
-            && other.interpolationMode == self.interpolationMode
-            && [other.stops isEqualToDictionary:self.stops]
-            && other.interpolationBase == self.interpolationBase);
-}
-
-- (NSUInteger)hash {
-    return  @(self.interpolationMode).hash + self.stops.hash + @(self.interpolationBase).hash;
-}
-
-@end
-
-@implementation MGLSourceStyleFunction
-
-@dynamic stops;
-
-+ (instancetype)functionWithInterpolationMode:(MGLInterpolationMode)interpolationMode stops:(NSDictionary *)stops attributeName:(NSString *)attributeName options:(NSDictionary *)options {
-    return [[self alloc] initWithInterpolationMode:interpolationMode stops:stops attributeName:attributeName options:options];
-}
-
-- (instancetype)initWithInterpolationBase:(CGFloat)interpolationBase stops:(NSDictionary *)stops {
-    return [self initWithInterpolationMode:MGLInterpolationModeExponential stops:stops attributeName:@"" options:@{MGLStyleFunctionOptionInterpolationBase: @(interpolationBase)}];
-}
-
-- (instancetype)initWithInterpolationMode:(MGLInterpolationMode)interpolationMode stops:(NSDictionary *)stops attributeName:(NSString *)attributeName options:(NSDictionary *)options {
-    if (self = [super init]) {
-        self.interpolationMode = interpolationMode;
-        self.stops = stops;
-        _attributeName = attributeName;
-
-        if ([options.allKeys containsObject:MGLStyleFunctionOptionDefaultValue]) {
-            if ([options[MGLStyleFunctionOptionDefaultValue] isKindOfClass:[MGLStyleValue class]]) {
-                MGLStyleValue *value = (MGLStyleValue *)options[MGLStyleFunctionOptionDefaultValue];
-                _defaultValue = value;
-            } else {
-                [NSException raise:NSInvalidArgumentException format:@"Default value must be an MGLStyleValue"];
-            }
-        }
-
-        if ([options.allKeys containsObject:MGLStyleFunctionOptionInterpolationBase]) {
-            if ([options[MGLStyleFunctionOptionInterpolationBase] isKindOfClass:[NSNumber class]]) {
-                NSNumber *value = (NSNumber *)options[MGLStyleFunctionOptionInterpolationBase];
-                self.interpolationBase = [value floatValue];
-            } else {
-                [NSException raise:NSInvalidArgumentException format:@"Interpolation base must be an NSNumber that represents a CGFloat."];
-            }
+    if (auto interpolateExpression = dynamic_cast<const InterpolateBase *>(&mbglExpression)) {
+        auto &interpolator = interpolateExpression->getInterpolator();
+        auto &input = interpolateExpression->getInput();
+        NSArray *interpolatorObject;
+        if (interpolator.is<ExponentialInterpolator>()) {
+            auto exponentialInterpolator = interpolator.get<ExponentialInterpolator>();
+            interpolatorObject = exponentialInterpolator.base == 1 ? @[@"linear"] : @[@"exponential", @(exponentialInterpolator.base)];
+        } else if (interpolator.is<CubicBezierInterpolator>()) {
+            auto cubicBezierInterpolator = interpolator.get<CubicBezierInterpolator>();
+            auto bezier = cubicBezierInterpolator.ub;
+            interpolatorObject = @[
+                @"cubic-bezier",
+                @(bezier.getP1().first), @(bezier.getP1().second),
+                @(bezier.getP2().first), @(bezier.getP2().second),
+            ];
+        } else {
+            NSCAssert(NO, @"Unrecognized interpolator type.");
         }
+        NSMutableArray *expressionObject = [NSMutableArray arrayWithObjects:@"interpolate", interpolatorObject, MGLJSONObjectFromMBGLExpression(*input.get()), nil];
+        interpolateExpression->eachStop([&](double stop, const Expression &child) {
+            [expressionObject addObject:@(stop)];
+            [expressionObject addObject:MGLJSONObjectFromMBGLExpression(child)];
+        });
+        return expressionObject;
     }
-    return self;
-}
-
-- (NSString *)description {
-    return [NSString stringWithFormat:@"<%@: %p, \
-            interpolationMode = %lu, \
-            stops = %@, \
-            attributeName = %@, \
-            defaultValue = %@, \
-            interpolationBase = %f>",
-            NSStringFromClass([self class]),
-            (void *)self,
-            (unsigned long)self.interpolationMode,
-            self.stops,
-            self.attributeName,
-            self.defaultValue,
-            self.interpolationBase];
-}
-
-- (BOOL)isEqual:(MGLSourceStyleFunction *)other {
-    return ([other isKindOfClass:[self class]]
-            && other.interpolationMode == self.interpolationMode
-            && ((self.stops && [other.stops isEqualToDictionary:self.stops]) || (!self.stops && !other.stops))
-            && [other.attributeName isEqual:self.attributeName]
-            && ((self.defaultValue && [other.defaultValue isEqual:self.defaultValue]) || (!self.defaultValue && !other.defaultValue))
-            && other.interpolationBase == self.interpolationBase);
-}
-
-- (NSUInteger)hash {
-    return @(self.interpolationMode).hash + self.stops.hash + self.attributeName.hash + self.defaultValue.hash + @(self.interpolationBase).hash;
-}
-
-@end
-
-@implementation MGLCompositeStyleFunction
-
-@dynamic stops;
-
-+ (instancetype)functionWithInterpolationMode:(MGLInterpolationMode)interpolationMode stops:(NSDictionary *)stops attributeName:(NSString *)attributeName options:(NSDictionary *)options {
-    return [[self alloc] initWithInterpolationMode:interpolationMode stops:stops attributeName:attributeName options:options];
-}
-
-- (instancetype)initWithInterpolationBase:(CGFloat)interpolationBase stops:(NSDictionary *)stops {
-    return [self initWithInterpolationMode:MGLInterpolationModeExponential stops:stops attributeName:@"" options:@{MGLStyleFunctionOptionInterpolationBase: @(interpolationBase)}];
-}
-
-- (instancetype)initWithInterpolationMode:(MGLInterpolationMode)interpolationMode stops:(NSDictionary *)stops attributeName:(NSString *)attributeName options:(NSDictionary *)options {
-    if (self = [super init]) {
-        self.interpolationMode = interpolationMode;
-        self.stops = stops;
-        _attributeName = attributeName;
-
-        if ([options.allKeys containsObject:MGLStyleFunctionOptionDefaultValue]) {
-            if ([options[MGLStyleFunctionOptionDefaultValue] isKindOfClass:[MGLStyleValue class]]) {
-                MGLStyleValue *value = (MGLStyleValue *)options[MGLStyleFunctionOptionDefaultValue];
-                _defaultValue = value;
-            } else {
-                [NSException raise:NSInvalidArgumentException format:@"Default value must be an MGLStyleValue"];
-            }
-        }
-
-        if ([options.allKeys containsObject:MGLStyleFunctionOptionInterpolationBase]) {
-            if ([options[MGLStyleFunctionOptionInterpolationBase] isKindOfClass:[NSNumber class]]) {
-                NSNumber *value = (NSNumber *)options[MGLStyleFunctionOptionInterpolationBase];
-                self.interpolationBase = [value floatValue];
-            } else {
-                [NSException raise:NSInvalidArgumentException format:@"Interpolation base must be an NSNumber that represents a CGFloat."];
-            }
-        }
+    if (auto caseExpression = dynamic_cast<const Case *>(&mbglExpression)) {
+        NSMutableArray *expressionObject = [NSMutableArray arrayWithObject:@"case"];
+        caseExpression->eachChild([&](const Expression &child) {
+            [expressionObject addObject:MGLJSONObjectFromMBGLExpression(child)];
+        });
+        return expressionObject;
     }
-    return self;
-}
-
-- (NSString *)description {
-    return [NSString stringWithFormat:@"<%@: %p, \
-            interpolationMode = %lu, \
-            stops = %@, \
-            attributeName = %@, \
-            defaultValue = %@, \
-            interpolationBase = %f>",
-            NSStringFromClass([self class]), (void *)self,
-            (unsigned long)self.interpolationMode,
-            self.stops,
-            self.attributeName,
-            self.defaultValue,
-            self.interpolationBase];
-}
-
-- (BOOL)isEqual:(MGLCompositeStyleFunction *)other {
-    return ([other isKindOfClass:[self class]]
-            && other.interpolationMode == self.interpolationMode
-            && [other.stops isEqualToDictionary:self.stops]
-            && [other.attributeName isEqual:self.attributeName]
-            && ((self.defaultValue && [other.defaultValue isEqual:self.defaultValue]) || (!self.defaultValue && !other.defaultValue))
-            && other.interpolationBase == self.interpolationBase);
-}
-
-- (NSUInteger)hash {
-    return  @(self.interpolationMode).hash + self.stops.hash + self.attributeName.hash + @(self.interpolationBase).hash;
+    NSCAssert(NO, @"Unrecognized expression type.");
+    return nil;
 }
 
-@end
diff --git a/platform/darwin/src/MGLStyleValue_Private.h b/platform/darwin/src/MGLStyleValue_Private.h
index 5914e0a2aa..ba4b413a3c 100644
--- a/platform/darwin/src/MGLStyleValue_Private.h
+++ b/platform/darwin/src/MGLStyleValue_Private.h
@@ -4,11 +4,13 @@
 
 #import "NSValue+MGLStyleAttributeAdditions.h"
 #import "NSValue+MGLAdditions.h"
+#import "NSExpression+MGLPrivateAdditions.h"
 #import "MGLTypes.h"
 
 #import "MGLConversion.h"
+#include <mbgl/style/conversion/property_value.hpp>
 #include <mbgl/style/conversion/data_driven_property_value.hpp>
-#include <mbgl/style/conversion.hpp>
+#include <mbgl/style/conversion/position.hpp>
 #import <mbgl/style/types.hpp>
 
 #import <mbgl/util/enum.hpp>
@@ -23,166 +25,68 @@
     #import "NSColor+MGLAdditions.h"
 #endif
 
+namespace mbgl {
+    namespace style {
+        namespace expression {
+            class Expression;
+        }
+    }
+}
+
+id MGLJSONObjectFromMBGLExpression(const mbgl::style::expression::Expression &mbglExpression);
+
 template <typename MBGLType, typename ObjCType, typename MBGLElement = MBGLType, typename ObjCEnum = ObjCType>
 class MGLStyleValueTransformer {
 public:
-
-    // Convert an mbgl property value into an mgl style value
-    MGLStyleValue<ObjCType> *toStyleValue(const mbgl::style::PropertyValue<MBGLType> &mbglValue) {
-        PropertyValueEvaluator evaluator;
-        return mbglValue.evaluate(evaluator);
-    }
-
-    // Convert an mbgl data driven property value into an mgl style value
-    MGLStyleValue<ObjCType> *toDataDrivenStyleValue(const mbgl::style::DataDrivenPropertyValue<MBGLType> &mbglValue) {
-        PropertyValueEvaluator evaluator;
+    
+    /// Convert an mbgl property value into an mgl style value
+    NSExpression *toExpression(const mbgl::style::PropertyValue<MBGLType> &mbglValue) {
+        PropertyExpressionEvaluator evaluator;
         return mbglValue.evaluate(evaluator);
     }
-
-    // Convert an mbgl property value containing an enum into an mgl style value
-    template <typename MBGLEnum = MBGLType,
-              class = typename std::enable_if<std::is_enum<MBGLEnum>::value>::type,
-              typename MGLEnum = ObjCEnum,
-              class = typename std::enable_if<std::is_enum<MGLEnum>::value>::type>
-    MGLStyleValue<ObjCType> *toEnumStyleValue(const mbgl::style::PropertyValue<MBGLEnum> &mbglValue) {
-        EnumPropertyValueEvaluator<MBGLEnum, ObjCEnum> evaluator;
+    
+    /// Convert an mbgl data driven property value into an mgl style value
+    template <typename MBGLEnum = MBGLType, typename MGLEnum = ObjCEnum>
+    NSExpression *toExpression(const mbgl::style::DataDrivenPropertyValue<MBGLEnum> &mbglValue) {
+        PropertyExpressionEvaluator evaluator;
         return mbglValue.evaluate(evaluator);
     }
-
-    // Convert an mgl style value into a non interpolatable (camera with interval stops) mbgl property value
-    mbgl::style::PropertyValue<MBGLType> toPropertyValue(MGLStyleValue<ObjCType> *value) {
-        if ([value isKindOfClass:[MGLSourceStyleFunction class]] || [value isKindOfClass:[MGLCompositeStyleFunction class]]) {
-            [NSException raise:NSInvalidArgumentException
-                        format:@"This property can only be set to camera functions. Use +[MGLStyleValue valueWithInterpolationMode:cameraStops:options:] instead."];
-            return {};
-        }
-
-        if ([value isKindOfClass:[MGLConstantStyleValue class]]) {
-            return toMBGLConstantValue((MGLConstantStyleValue<ObjCType> *)value);
-        } else if ([value isKindOfClass:[MGLCameraStyleFunction class]]) {
-            MGLCameraStyleFunction<ObjCType> *cameraStyleFunction = (MGLCameraStyleFunction<ObjCType> *)value;
-            // Intentionally ignore the stop type set by the developer becuase non interpolatable property values
-            // can only have interval stops. This also allows for backwards compatiblity when the developer uses
-            // a deprecated MGLStyleValue method (that used to create an MGLStyleFunction) to create a function
-            // for properties that are piecewise-constant (i.e. enum, bool, string)
-            return toMBGLIntervalCameraFunction(cameraStyleFunction);
-        } else if ([value isMemberOfClass:[MGLStyleFunction class]]) {
-            MGLStyleFunction<ObjCType> *styleFunction = (MGLStyleFunction<ObjCType> *)value;
-            return toMBGLIntervalCameraFunction(styleFunction);
-        } else if (value) {
-            [NSException raise:@"MGLAbstractClassException" format:
-             @"The style value %@ cannot be applied to the style. "
-             @"Make sure the style value was created as a member of a concrete subclass of MGLStyleValue.",
-             NSStringFromClass([value class])];
-            return {};
-        } else {
-            return {};
-        }
-    }
-
-    // Convert an mgl style value into a non interpolatable (camera with exponential or interval stops) mbgl property value
-    mbgl::style::PropertyValue<MBGLType> toInterpolatablePropertyValue(MGLStyleValue<ObjCType> *value) {
-        if ([value isKindOfClass:[MGLSourceStyleFunction class]] || [value isKindOfClass:[MGLCompositeStyleFunction class]]) {
-            [NSException raise:NSInvalidArgumentException
-                        format:@"This property can only be set to camera functions. Use +[MGLStyleValue valueWithInterpolationMode:cameraStops:options:] instead."];
+    
+    /**
+     Converts an NSExpression to an mbgl property value.
+     */
+    template <typename MBGLValue>
+    MBGLValue toPropertyValue(NSExpression *expression) {
+        if (!expression) {
             return {};
         }
-
-        if ([value isKindOfClass:[MGLConstantStyleValue class]]) {
-            return toMBGLConstantValue((MGLConstantStyleValue<ObjCType> *)value);
-        } else if ([value isMemberOfClass:[MGLStyleFunction class]]) {
-            MGLStyleFunction<ObjCType> *styleFunction = (MGLStyleFunction<ObjCType> *)value;
-            return toMBGLExponentialCameraFunction(styleFunction);
-        } else if ([value isKindOfClass:[MGLCameraStyleFunction class]]) {
-            MGLCameraStyleFunction<ObjCType> *cameraStyleFunction = (MGLCameraStyleFunction<ObjCType> *)value;
-            switch (cameraStyleFunction.interpolationMode) {
-                case MGLInterpolationModeExponential:
-                    return toMBGLExponentialCameraFunction(cameraStyleFunction);
-                    break;
-                case MGLInterpolationModeInterval:
-                    return toMBGLIntervalCameraFunction(cameraStyleFunction);
-                    break;
-                default:
-                    [NSException raise:NSInvalidArgumentException
-                                format:@"A camera function must use either exponential or interval stops."];
-                    break;
-            }
-            return {};
-        } else if (value) {
-            [NSException raise:@"MGLAbstractClassException" format:
-             @"The style value %@ cannot be applied to the style. "
-             @"Make sure the style value was created as a member of a concrete subclass of MGLStyleValue.",
-             NSStringFromClass([value class])];
-            return {};
-        } else {
-            return {};
+        
+        if (expression.expressionType == NSConstantValueExpressionType) {
+            MBGLType mbglValue;
+            getMBGLValue(expression.constantValue, mbglValue);
+            return mbglValue;
         }
-    }
-
-    // Convert an mgl style value into a mbgl data driven property value
-    mbgl::style::DataDrivenPropertyValue<MBGLType> toDataDrivenPropertyValue(MGLStyleValue<ObjCType> *value) {
-        if ([value isKindOfClass:[MGLConstantStyleValue class]]) {
-            return toMBGLConstantValue((MGLConstantStyleValue<ObjCType> *)value);
-        } else if ([value isKindOfClass:[MGLStyleFunction class]]) {
-            mbgl::style::conversion::Error error;
-            auto result = mbgl::style::conversion::convert<mbgl::style::DataDrivenPropertyValue<MBGLType>>(
-                mbgl::style::conversion::makeConvertible(toRawStyleSpecValue((MGLStyleFunction<ObjCType> *) value)), error);
-            NSCAssert(result, @(error.message.c_str()));
-            return *result;
-        } else {
-            return {};
+        if (expression.expressionType == NSAggregateExpressionType) {
+            MBGLType mbglValue;
+            getMBGLValue(expression.collection, mbglValue);
+            return mbglValue;
         }
-    }
-
-    // Convert an mgl style value containing an enum into a mbgl property value containing an enum
-    template <typename MBGLEnum = MBGLType,
-              class = typename std::enable_if<std::is_enum<MBGLEnum>::value>::type,
-              typename MGLEnum = ObjCEnum,
-              class = typename std::enable_if<std::is_enum<MGLEnum>::value>::type>
-    mbgl::style::PropertyValue<MBGLEnum> toEnumPropertyValue(MGLStyleValue<ObjCType> *value) {
-        if ([value isKindOfClass:[MGLSourceStyleFunction class]] || [value isKindOfClass:[MGLCompositeStyleFunction class]]) {
+        
+        NSArray *jsonExpression = expression.mgl_jsonExpressionObject;
+        
+        mbgl::style::conversion::Error valueError;
+        auto value = mbgl::style::conversion::convert<MBGLValue>(
+            mbgl::style::conversion::makeConvertible(jsonExpression), valueError);
+        if (!value) {
             [NSException raise:NSInvalidArgumentException
-                        format:@"This property can only be set to camera functions. Use +[MGLStyleValue valueWithInterpolationMode:cameraStops:options:] instead."];
-            return {};
-        }
-
-        if ([value isKindOfClass:[MGLConstantStyleValue class]]) {
-            MBGLEnum mbglValue;
-            getMBGLValue([(MGLConstantStyleValue<ObjCType> *)value rawValue], mbglValue);
-            return mbglValue;
-        } else if ([value isKindOfClass:[MGLCameraStyleFunction class]]) {
-            MGLCameraStyleFunction<NSValue *> *cameraStyleFunction = (MGLCameraStyleFunction<NSValue *> *)value;
-            __block std::map<float, MBGLType> stops = {};
-            [cameraStyleFunction.stops enumerateKeysAndObjectsUsingBlock:^(NSNumber * _Nonnull zoomKey, MGLStyleValue<NSValue *> * _Nonnull stopValue, BOOL * _Nonnull stop) {
-                NSCAssert([stopValue isKindOfClass:[MGLStyleValue class]], @"Stops should be MGLStyleValues");
-                auto mbglStopValue = toEnumPropertyValue(stopValue);
-                NSCAssert(mbglStopValue.isConstant(), @"Stops must be constant");
-                stops[zoomKey.floatValue] = mbglStopValue.asConstant();
-            }];
-
-            // Enumerations can only ever use interval stops.
-            mbgl::style::IntervalStops<MBGLType> intervalStops = {stops};
-
-            mbgl::style::CameraFunction<MBGLType> cameraFunction = {intervalStops};
-            return cameraFunction;
-        } else if (value) {
-            [NSException raise:@"MGLAbstractClassException" format:
-             @"The style value %@ cannot be applied to the style. "
-             @"Make sure the style value was created as a member of a concrete subclass of MGLStyleValue.",
-             NSStringFromClass([value class])];
-            return {};
-        } else {
+                        format:@"Invalid property value: %@", @(valueError.message.c_str())];
             return {};
         }
+        
+        return *value;
     }
 
 private: // Private utilities for converting from mgl to mbgl values
-
-    MBGLType toMBGLConstantValue(MGLConstantStyleValue<ObjCType> *value) {
-        MBGLType mbglValue;
-        getMBGLValue(value.rawValue, mbglValue);
-        return mbglValue;
-    }
     
     /**
      As hack to allow converting enum => string values, we accept a second, dummy parameter in
@@ -220,164 +124,6 @@ private: // Private utilities for converting from mgl to mbgl values
         return @(color.mgl_color.stringify().c_str());
     }
 
-    
-    NSObject* toRawStyleSpecValue(MGLStyleFunction<ObjCType>* styleFunction) {
-        NSMutableDictionary * rawFunction = [NSMutableDictionary new];
-        // interpolationMode => type
-        switch (styleFunction.interpolationMode) {
-            case MGLInterpolationModeExponential:
-                rawFunction[@"type"] = @"exponential";
-                break;
-            case MGLInterpolationModeInterval:
-                rawFunction[@"type"] = @"interval";
-                break;
-            case MGLInterpolationModeCategorical:
-                rawFunction[@"type"] = @"categorical";
-                break;
-            case MGLInterpolationModeIdentity:
-                rawFunction[@"type"] = @"identity";
-                break;
-        }
-        
-        // interpolationBase => base
-        if (styleFunction.interpolationBase) {
-            rawFunction[@"base"] = @(styleFunction.interpolationBase);
-        }
-        
-        // stops and default value
-        if ([styleFunction isKindOfClass:[MGLCameraStyleFunction class]]) {
-            // zoom-only function (no default value)
-            __block NSMutableArray *stops = [[NSMutableArray alloc] init];
-            [styleFunction.stops enumerateKeysAndObjectsUsingBlock:^(NSNumber * _Nonnull zoomKey, MGLConstantStyleValue<ObjCType> * _Nonnull outputValue, BOOL * _Nonnull stop) {
-                MBGLType dummyMbglValue;
-                NSArray *rawStop = @[zoomKey, toRawStyleSpecValue([outputValue rawValue], dummyMbglValue)];
-                [stops addObject:rawStop];
-            }];
-            rawFunction[@"stops"] = stops;
-
-        } else if ([styleFunction isKindOfClass:[MGLSourceStyleFunction class]]) {
-            auto sourceStyleFunction = (MGLSourceStyleFunction<ObjCType> *)styleFunction;
-            rawFunction[@"property"] = sourceStyleFunction.attributeName;
-            // property-only function
-            __block NSMutableArray *stops = [[NSMutableArray alloc] init];
-            [styleFunction.stops enumerateKeysAndObjectsUsingBlock:^(NSObject * _Nonnull propertyKey, MGLConstantStyleValue<ObjCType> * _Nonnull outputValue, BOOL * _Nonnull stop) {
-                MBGLType dummyMbglValue;
-                NSArray *rawStop = @[propertyKey, toRawStyleSpecValue([outputValue rawValue], dummyMbglValue)];
-                [stops addObject:rawStop];
-            }];
-            rawFunction[@"stops"] = stops;
-            
-            // defaultValue => default
-            if (sourceStyleFunction.defaultValue) {
-                NSCAssert([sourceStyleFunction.defaultValue isKindOfClass:[MGLConstantStyleValue class]], @"Default value must be constant");
-                MBGLType dummyMbglValue;
-                rawFunction[@"default"] = toRawStyleSpecValue([(MGLConstantStyleValue<ObjCType> *)sourceStyleFunction.defaultValue rawValue], dummyMbglValue);
-            }
-        } else if ([styleFunction isKindOfClass:[MGLCompositeStyleFunction class]]) {
-            // zoom-and-property function
-            auto compositeStyleFunction = (MGLCompositeStyleFunction<ObjCType> *)styleFunction;
-            rawFunction[@"property"] = compositeStyleFunction.attributeName;
-            
-            __block NSMutableArray *stops = [[NSMutableArray alloc] init];
-            [compositeStyleFunction.stops enumerateKeysAndObjectsUsingBlock:^(NSNumber * _Nonnull zoomKey, NSDictionary * _Nonnull stopValue, BOOL * _Nonnull stop) {
-                for (NSObject *valueKey in stopValue.allKeys) {
-                    NSDictionary *stopKey = @{
-                         @"zoom": zoomKey,
-                         @"value": valueKey
-                     };
-                    MGLConstantStyleValue<ObjCType> *outputValue = stopValue[valueKey];
-                    NSCAssert([outputValue isKindOfClass:[MGLConstantStyleValue<ObjCType> class]], @"Stop outputs should be MGLConstantStyleValues");
-                    MBGLType dummyMbglValue;
-                    NSArray *rawStop = @[stopKey, toRawStyleSpecValue([outputValue rawValue], dummyMbglValue)];
-                    [stops addObject:rawStop];
-                }
-            }];
-            rawFunction[@"stops"] = stops;
-            
-            // defaultValue => default
-            if (compositeStyleFunction.defaultValue) {
-                NSCAssert([compositeStyleFunction.defaultValue isKindOfClass:[MGLConstantStyleValue class]], @"Default value must be constant");
-                MBGLType dummyMbglValue;
-                rawFunction[@"default"] = toRawStyleSpecValue([(MGLConstantStyleValue<ObjCType> *)compositeStyleFunction.defaultValue rawValue], dummyMbglValue);
-            }
-        }
-        
-        return rawFunction;
-    }
-
-    mbgl::style::CameraFunction<MBGLType> toMBGLExponentialCameraFunction(MGLStyleFunction<ObjCType> *styleFunction) {
-        __block std::map<float, MBGLType> stops = {};
-        [styleFunction.stops enumerateKeysAndObjectsUsingBlock:^(NSNumber * _Nonnull zoomKey, MGLStyleValue<ObjCType> * _Nonnull stopValue, BOOL * _Nonnull stop) {
-            NSCAssert([stopValue isKindOfClass:[MGLStyleValue class]], @"Stops should be MGLStyleValues");
-            auto mbglStopValue = toPropertyValue(stopValue);
-            NSCAssert(mbglStopValue.isConstant(), @"Stops must be constant");
-            stops[zoomKey.floatValue] = mbglStopValue.asConstant();
-        }];
-
-        // Camera function with Exponential stops
-        mbgl::style::ExponentialStops<MBGLType> exponentialStops = {stops, (float)styleFunction.interpolationBase};
-        mbgl::style::CameraFunction<MBGLType> cameraFunction = {exponentialStops};
-
-        return cameraFunction;
-    }
-
-    mbgl::style::CameraFunction<MBGLType> toMBGLIntervalCameraFunction(MGLStyleFunction<ObjCType> *styleFunction) {
-        __block std::map<float, MBGLType> stops = {};
-        [styleFunction.stops enumerateKeysAndObjectsUsingBlock:^(NSNumber * _Nonnull zoomKey, MGLStyleValue<ObjCType> * _Nonnull stopValue, BOOL * _Nonnull stop) {
-            NSCAssert([stopValue isKindOfClass:[MGLStyleValue class]], @"Stops should be MGLStyleValues");
-            auto mbglStopValue = toPropertyValue(stopValue);
-            NSCAssert(mbglStopValue.isConstant(), @"Stops must be constant");
-            stops[zoomKey.floatValue] = mbglStopValue.asConstant();
-        }];
-
-        // Camera function with Interval stops
-        mbgl::style::IntervalStops<MBGLType> intervalStops = {stops};
-        mbgl::style::CameraFunction<MBGLType> cameraFunction = {intervalStops};
-
-        return cameraFunction;
-    }
-
-    mbgl::style::SourceFunction<MBGLType> toMBGLCategoricalSourceFunction(MGLSourceStyleFunction<ObjCType> *sourceStyleFunction) {
-        __block std::map<mbgl::style::CategoricalValue, MBGLType> stops = {};
-        [sourceStyleFunction.stops enumerateKeysAndObjectsUsingBlock:^(id categoryKey, MGLStyleValue<ObjCType> *stopValue, BOOL *stop) {
-            NSCAssert([stopValue isKindOfClass:[MGLStyleValue class]], @"Stops should be MGLStyleValues");
-            auto mbglStopValue = toPropertyValue(stopValue);
-            NSCAssert(mbglStopValue.isConstant(), @"Stops must be constant");
-
-            if ([categoryKey isKindOfClass:[NSString class]]) {
-                const std::string& convertedValueKey = [((NSString *)categoryKey) UTF8String];
-                stops[mbgl::style::CategoricalValue(convertedValueKey)] = mbglStopValue.asConstant();
-            } else if ([categoryKey isKindOfClass:[NSNumber class]]) {
-                NSNumber *key = (NSNumber *)categoryKey;
-                if ((strcmp([key objCType], @encode(char)) == 0) ||
-                    (strcmp([key objCType], @encode(BOOL)) == 0)) {
-                    stops[mbgl::style::CategoricalValue((bool)[key boolValue])] = mbglStopValue.asConstant();
-                } else if (strcmp([key objCType], @encode(double)) == 0 ||
-                           strcmp([key objCType], @encode(float)) == 0) {
-                    NSCAssert(mbglStopValue.isConstant(), @"Categorical stop keys must be strings, booleans, or integers");
-                } else if ([key compare:@(0)] == NSOrderedDescending ||
-                           [key compare:@(0)] == NSOrderedSame ||
-                           [key compare:@(0)] == NSOrderedAscending) {
-                    stops[mbgl::style::CategoricalValue((int64_t)[key integerValue])] = mbglStopValue.asConstant();
-                }
-            }
-        }];
-        mbgl::style::CategoricalStops<MBGLType> categoricalStops = {stops};
-        mbgl::style::SourceFunction<MBGLType> sourceFunction = {sourceStyleFunction.attributeName.UTF8String, categoricalStops};
-        setDefaultMBGLValue(sourceStyleFunction, sourceFunction);
-        return sourceFunction;
-    }
-
-    void setDefaultMBGLValue(MGLSourceStyleFunction<ObjCType> *sourceStyleFunction, mbgl::style::SourceFunction<MBGLType> &sourceFunction) {
-        if (sourceStyleFunction.defaultValue) {
-            NSCAssert([sourceStyleFunction.defaultValue isKindOfClass:[MGLConstantStyleValue class]], @"Default value must be constant");
-            MBGLType mbglValue;
-            id mglValue = [(MGLConstantStyleValue<ObjCType> *)sourceStyleFunction.defaultValue rawValue];
-            getMBGLValue(mglValue, mbglValue);
-            sourceFunction.defaultValue = mbglValue;
-        }
-    }
-
     // Bool
     void getMBGLValue(NSNumber *rawValue, bool &mbglValue) {
         mbglValue = !!rawValue.boolValue;
@@ -394,13 +140,28 @@ private: // Private utilities for converting from mgl to mbgl values
     }
 
     // Offsets
-    void getMBGLValue(NSValue *rawValue, std::array<float, 2> &mbglValue) {
-        mbglValue = rawValue.mgl_offsetArrayValue;
+    void getMBGLValue(id rawValue, std::array<float, 2> &mbglValue) {
+        if ([rawValue isKindOfClass:[NSValue class]]) {
+            mbglValue = [rawValue mgl_offsetArrayValue];
+        } else if ([rawValue isKindOfClass:[NSArray class]]) {
+            NSArray *array = (NSArray *)rawValue;
+            getMBGLValue(array[0], mbglValue[0]);
+            getMBGLValue(array[1], mbglValue[1]);
+        }
     }
 
     // Padding
-    void getMBGLValue(NSValue *rawValue, std::array<float, 4> &mbglValue) {
-        mbglValue = rawValue.mgl_paddingArrayValue;
+    void getMBGLValue(id rawValue, std::array<float, 4> &mbglValue) {
+        if ([rawValue isKindOfClass:[NSValue class]]) {
+            mbglValue = [rawValue mgl_paddingArrayValue];
+        } else if ([rawValue isKindOfClass:[NSArray class]]) {
+            NSArray *array = (NSArray *)rawValue;
+            getMBGLValue(array[0], mbglValue[0]);
+            getMBGLValue(array[1], mbglValue[1]);
+            getMBGLValue(array[2], mbglValue[2]);
+            getMBGLValue(array[3], mbglValue[3]);
+            getMBGLValue(array[4], mbglValue[4]);
+        }
     }
 
     // Color
@@ -412,8 +173,12 @@ private: // Private utilities for converting from mgl to mbgl values
     void getMBGLValue(ObjCType rawValue, std::vector<MBGLElement> &mbglValue) {
         mbglValue.reserve(rawValue.count);
         for (id obj in rawValue) {
+            id constantObject = obj;
+            if ([obj isKindOfClass:[NSExpression class]] && [obj expressionType] == NSConstantValueExpressionType) {
+                constantObject = [constantObject constantValue];
+            }
             MBGLElement mbglElement;
-            getMBGLValue(obj, mbglElement);
+            getMBGLValue(constantObject, mbglElement);
             mbglValue.push_back(mbglElement);
         }
     }
@@ -429,11 +194,15 @@ private: // Private utilities for converting from mgl to mbgl values
     class = typename std::enable_if<std::is_enum<MBGLEnum>::value>::type,
     typename MGLEnum = ObjCEnum,
     class = typename std::enable_if<std::is_enum<MGLEnum>::value>::type>
-    void getMBGLValue(ObjCType rawValue, MBGLEnum &mbglValue) {
-        MGLEnum mglEnum;
-        [rawValue getValue:&mglEnum];
-        auto str = mbgl::Enum<MGLEnum>::toString(mglEnum);
-        mbglValue = *mbgl::Enum<MBGLEnum>::toEnum(str);
+    void getMBGLValue(id rawValue, MBGLEnum &mbglValue) {
+        if ([rawValue isKindOfClass:[NSString class]]) {
+            mbglValue = *mbgl::Enum<MBGLEnum>::toEnum([(NSString *)rawValue UTF8String]);
+        } else {
+            MGLEnum mglEnum;
+            [(NSValue *)rawValue getValue:&mglEnum];
+            auto str = mbgl::Enum<MGLEnum>::toString(mglEnum);
+            mbglValue = *mbgl::Enum<MBGLEnum>::toEnum(str);
+        }
     }
 
 private: // Private utilities for converting from mbgl to mgl values
@@ -477,7 +246,7 @@ private: // Private utilities for converting from mbgl to mgl values
     static ObjCType toMGLRawStyleValue(const std::vector<MBGLElement> &mbglStopValue) {
         NSMutableArray *array = [NSMutableArray arrayWithCapacity:mbglStopValue.size()];
         for (const auto &mbglElement: mbglStopValue) {
-            [array addObject:toMGLRawStyleValue(mbglElement)];
+            [array addObject:[NSExpression expressionForConstantValue:toMGLRawStyleValue(mbglElement)]];
         }
         return array;
     }
@@ -496,212 +265,49 @@ private: // Private utilities for converting from mbgl to mgl values
         return [NSValue value:&mglType withObjCType:@encode(MGLEnum)];
     }
 
-    // Converts mbgl stops to an equivilent NSDictionary for mgl
-    static NSMutableDictionary *toConvertedStops(const std::map<float, MBGLType> &mbglStops) {
-        NSMutableDictionary *stops = [NSMutableDictionary dictionaryWithCapacity:mbglStops.size()];
-        for (const auto &mbglStop : mbglStops) {
-            auto rawValue = toMGLRawStyleValue(mbglStop.second);
-            stops[@(mbglStop.first)] = [MGLStyleValue valueWithRawValue:rawValue];
-        }
-        return stops;
-    }
-
-    // Converts mbgl interval stop categorical values to an equivilant object for mgl
-    class CategoricalValueVisitor {
-    public:
-        id operator()(const bool value) {
-            return toMGLRawStyleValue(value);
-        }
-
-        id operator()(const int64_t value) {
-            return toMGLRawStyleValue(value);
-        }
-
-        id operator()(const std::string value) {
-            return toMGLRawStyleValue(value);
-        }
-    };
-
-    // Converts all types of mbgl property values containing enumerations into an equivilant mgl style value
-    template <typename MBGLEnum = MBGLType, typename MGLEnum = ObjCEnum>
-    class EnumPropertyValueEvaluator {
+    /// Converts all types of mbgl property values into an equivalent NSExpression.
+    class PropertyExpressionEvaluator {
     public:
-        id operator()(const mbgl::style::Undefined) const {
+        NSExpression *operator()(const mbgl::style::Undefined) const {
             return nil;
         }
 
-        id operator()(const MBGLEnum &value) const {
-            auto str = mbgl::Enum<MBGLEnum>::toString(value);
-            MGLEnum mglType = *mbgl::Enum<MGLEnum>::toEnum(str);
-            return [MGLConstantStyleValue<ObjCType> valueWithRawValue:[NSValue value:&mglType withObjCType:@encode(MGLEnum)]];
-        }
-
-        id operator()(const mbgl::style::CameraFunction<MBGLEnum> &mbglValue) const {
-            CameraFunctionStopsVisitor visitor;
-            return apply_visitor(visitor, mbglValue.stops);
-        }
-    };
-
-    // Converts all possible mbgl camera function stops into an equivilant mgl style value
-    class CameraFunctionStopsVisitor {
-    public:
-        id operator()(const mbgl::style::ExponentialStops<MBGLType> &mbglStops) {
-            return [MGLCameraStyleFunction functionWithInterpolationMode:MGLInterpolationModeExponential
-                                                          stops:toConvertedStops(mbglStops.stops)
-                                                        options:@{MGLStyleFunctionOptionInterpolationBase: @(mbglStops.base)}];
-        }
-
-        id operator()(const mbgl::style::IntervalStops<MBGLType> &mbglStops) {
-            return [MGLCameraStyleFunction functionWithInterpolationMode:MGLInterpolationModeInterval
-                                                          stops:toConvertedStops(mbglStops.stops)
-                                                        options:nil];
-        }
-    };
-
-    // Converts a source function and all possible mbgl source function stops into an equivilant mgl style value
-    class SourceFunctionStopsVisitor {
-    public:
-        id operator()(const mbgl::style::ExponentialStops<MBGLType> &mbglStops) {
-            MGLSourceStyleFunction *sourceFunction = [MGLSourceStyleFunction functionWithInterpolationMode:MGLInterpolationModeExponential
-                                                                                            stops:toConvertedStops(mbglStops.stops)
-                                                                                    attributeName:@(mbglFunction.property.c_str())
-                                                                                          options:@{MGLStyleFunctionOptionInterpolationBase: @(mbglStops.base)}];
-            if (mbglFunction.defaultValue) {
-                sourceFunction.defaultValue = [MGLStyleValue valueWithRawValue:toMGLRawStyleValue(*mbglFunction.defaultValue)];
+        /**
+         As hack to allow converting enum => string values, we accept a second, dummy parameter in
+         the toRawStyleSpecValue() methods for converting 'atomic' (non-style-function) values.
+         This allows us to use `std::enable_if` to test (at compile time) whether or not MBGLType is an Enum.
+         */
+        template <typename MBGLEnum = MBGLType,
+            class = typename std::enable_if<!std::is_enum<MBGLEnum>::value>::type,
+        typename MGLEnum = ObjCEnum,
+            class = typename std::enable_if<!std::is_enum<MGLEnum>::value>::type>
+        NSExpression *operator()(const MBGLType &value) const {
+            id constantValue = toMGLRawStyleValue(value);
+            if ([constantValue isKindOfClass:[NSArray class]]) {
+                return [NSExpression expressionForAggregate:constantValue];
             }
-            return sourceFunction;
+            return [NSExpression expressionForConstantValue:constantValue];
         }
-
-        id operator()(const mbgl::style::IntervalStops<MBGLType> &mbglStops) {
-            MGLSourceStyleFunction *sourceFunction = [MGLSourceStyleFunction functionWithInterpolationMode:MGLInterpolationModeInterval
-                                                                                            stops:toConvertedStops(mbglStops.stops)
-                                                                                    attributeName:@(mbglFunction.property.c_str())
-                                                                                          options:nil];
-            if (mbglFunction.defaultValue) {
-                sourceFunction.defaultValue = [MGLStyleValue valueWithRawValue:toMGLRawStyleValue(*mbglFunction.defaultValue)];
-            }
-            return sourceFunction;
-        }
-
-        id operator()(const mbgl::style::CategoricalStops<MBGLType> &mbglStops) {
-            NSMutableDictionary *stops = [NSMutableDictionary dictionaryWithCapacity:mbglStops.stops.size()];
-            for (const auto &mbglStop : mbglStops.stops) {
-                auto categoricalValue = mbglStop.first;
-                auto rawValue = toMGLRawStyleValue(mbglStop.second);
-                CategoricalValueVisitor categoricalValueVisitor;
-                id stopKey = apply_visitor(categoricalValueVisitor, categoricalValue);
-                stops[stopKey] = [MGLStyleValue valueWithRawValue:rawValue];
-            }
-
-            MGLSourceStyleFunction *sourceFunction = [MGLSourceStyleFunction functionWithInterpolationMode:MGLInterpolationModeCategorical
-                                                                                            stops:stops
-                                                                                    attributeName:@(mbglFunction.property.c_str())
-                                                                                          options:nil];
-            if (mbglFunction.defaultValue) {
-                sourceFunction.defaultValue = [MGLStyleValue valueWithRawValue:toMGLRawStyleValue(*mbglFunction.defaultValue)];
-            }
-            return sourceFunction;
-
-        }
-
-        id operator()(const mbgl::style::IdentityStops<MBGLType> &mbglStops) {
-            MGLSourceStyleFunction *sourceFunction = [MGLSourceStyleFunction functionWithInterpolationMode:MGLInterpolationModeIdentity
-                                                                                                     stops:nil
-                                                                                             attributeName:@(mbglFunction.property.c_str()) options:nil];
-            if (mbglFunction.defaultValue) {
-                sourceFunction.defaultValue = [MGLStyleValue valueWithRawValue:toMGLRawStyleValue(*mbglFunction.defaultValue)];
-            }
-            return sourceFunction;
-        }
-
-        const mbgl::style::SourceFunction<MBGLType> &mbglFunction;
-    };
-
-    // Converts a composite function and all possible mbgl stops into an equivilant mgl style value
-    class CompositeFunctionStopsVisitor {
-    public:
-        id operator()(const mbgl::style::CompositeExponentialStops<MBGLType> &mbglStops) {
-            NSMutableDictionary *stops = [NSMutableDictionary dictionaryWithCapacity:mbglStops.stops.size()];
-            for (auto const& outerStop: mbglStops.stops) {
-                stops[@(outerStop.first)] = toConvertedStops(outerStop.second);
-            }
-            MGLCompositeStyleFunction *compositeFunction = [MGLCompositeStyleFunction functionWithInterpolationMode:MGLInterpolationModeExponential
-                                                                                                     stops:stops
-                                                                                             attributeName:@(mbglFunction.property.c_str())
-                                                                                                   options:@{MGLStyleFunctionOptionInterpolationBase: @(mbglStops.base)}];
-            if (mbglFunction.defaultValue) {
-                compositeFunction.defaultValue = [MGLStyleValue valueWithRawValue:toMGLRawStyleValue(*mbglFunction.defaultValue)];
-            }
-            return compositeFunction;
-        }
-
-        id operator()(const mbgl::style::CompositeIntervalStops<MBGLType> &mbglStops) {
-            NSMutableDictionary *stops = [NSMutableDictionary dictionaryWithCapacity:mbglStops.stops.size()];
-            for (auto const& outerStop: mbglStops.stops) {
-                stops[@(outerStop.first)] = toConvertedStops(outerStop.second);
-            }
-            MGLCompositeStyleFunction *compositeFunction = [MGLCompositeStyleFunction functionWithInterpolationMode:MGLInterpolationModeInterval
-                                                                                                     stops:stops
-                                                                                             attributeName:@(mbglFunction.property.c_str())
-                                                                                                   options:nil];
-            if (mbglFunction.defaultValue) {
-                compositeFunction.defaultValue = [MGLStyleValue valueWithRawValue:toMGLRawStyleValue(*mbglFunction.defaultValue)];
-            }
-            return compositeFunction;
-        }
-
-        id operator()(const mbgl::style::CompositeCategoricalStops<MBGLType> &mbglStops) {
-            NSMutableDictionary *stops = [NSMutableDictionary dictionaryWithCapacity:mbglStops.stops.size()];
-            for (auto const& outerStop: mbglStops.stops) {
-                    NSMutableDictionary *innerStops = [NSMutableDictionary dictionaryWithCapacity:outerStop.second.size()];
-                for (const auto &mbglStop : outerStop.second) {
-                    auto categoricalValue = mbglStop.first;
-                    auto rawValue = toMGLRawStyleValue(mbglStop.second);
-                    CategoricalValueVisitor categoricalValueVisitor;
-                    id stopKey = apply_visitor(categoricalValueVisitor, categoricalValue);
-                    innerStops[stopKey] = [MGLStyleValue valueWithRawValue:rawValue];
-                }
-                stops[@(outerStop.first)] = innerStops;
-            }
-
-            MGLCompositeStyleFunction *compositeFunction = [MGLCompositeStyleFunction functionWithInterpolationMode:MGLInterpolationModeCategorical
-                                                                                                     stops:stops attributeName:@(mbglFunction.property.c_str())
-                                                                                                   options:nil];
-            if (mbglFunction.defaultValue) {
-                compositeFunction.defaultValue = [MGLStyleValue valueWithRawValue:toMGLRawStyleValue(*mbglFunction.defaultValue)];
-            }
-            return compositeFunction;
-        }
-
-        const mbgl::style::CompositeFunction<MBGLType> &mbglFunction;
-    };
-
-
-    // Converts all types of mbgl property values that don't contain enumerations into an equivilant mgl style value
-    class PropertyValueEvaluator {
-    public:
-        id operator()(const mbgl::style::Undefined) const {
-            return nil;
-        }
-
-        id operator()(const MBGLType &value) const {
-            auto rawValue = toMGLRawStyleValue(value);
-            return [MGLConstantStyleValue<ObjCType> valueWithRawValue:rawValue];
+        
+        template <typename MBGLEnum = MBGLType,
+            class = typename std::enable_if<std::is_enum<MBGLEnum>::value>::type,
+        typename MGLEnum = ObjCEnum,
+            class = typename std::enable_if<std::is_enum<MGLEnum>::value>::type>
+        NSExpression *operator()(const MBGLEnum &value) const {
+            NSString *constantValue = @(mbgl::Enum<MBGLEnum>::toString(value));
+            return [NSExpression expressionForConstantValue:constantValue];
         }
 
-        id operator()(const mbgl::style::CameraFunction<MBGLType> &mbglValue) const {
-            CameraFunctionStopsVisitor visitor;
-            return apply_visitor(visitor, mbglValue.stops);
+        NSExpression *operator()(const mbgl::style::CameraFunction<MBGLType> &mbglValue) const {
+            return [NSExpression mgl_expressionWithJSONObject:MGLJSONObjectFromMBGLExpression(mbglValue.getExpression())];
         }
 
-        id operator()(const mbgl::style::SourceFunction<MBGLType> &mbglValue) const {
-            SourceFunctionStopsVisitor visitor { mbglValue };
-            return apply_visitor(visitor, mbglValue.stops);
+        NSExpression *operator()(const mbgl::style::SourceFunction<MBGLType> &mbglValue) const {
+            return [NSExpression mgl_expressionWithJSONObject:MGLJSONObjectFromMBGLExpression(mbglValue.getExpression())];
         }
 
-        MGLCompositeStyleFunction<ObjCType> * operator()(const mbgl::style::CompositeFunction<MBGLType> &mbglValue) const {
-            CompositeFunctionStopsVisitor visitor { mbglValue };
-            return apply_visitor(visitor, mbglValue.stops);
+        NSExpression *operator()(const mbgl::style::CompositeFunction<MBGLType> &mbglValue) const {
+            return [NSExpression mgl_expressionWithJSONObject:MGLJSONObjectFromMBGLExpression(mbglValue.getExpression())];
         }
     };
 };
diff --git a/platform/darwin/src/MGLSymbolStyleLayer.h b/platform/darwin/src/MGLSymbolStyleLayer.h
index 84d32cd0b1..1017db5442 100644
--- a/platform/darwin/src/MGLSymbolStyleLayer.h
+++ b/platform/darwin/src/MGLSymbolStyleLayer.h
@@ -2,7 +2,6 @@
 // Edit platform/darwin/scripts/generate-style-code.js, then run `make darwin-style-code`.
 
 #import "MGLFoundation.h"
-#import "MGLStyleValue.h"
 #import "MGLVectorStyleLayer.h"
 
 NS_ASSUME_NONNULL_BEGIN
@@ -335,12 +334,12 @@ typedef NS_ENUM(NSUInteger, MGLTextTranslationAnchor) {
  ```swift
  let layer = MGLSymbolStyleLayer(identifier: "coffeeshops", source: pois)
  layer.sourceLayerIdentifier = "pois"
- layer.iconImageName = MGLStyleValue(rawValue: "coffee")
- layer.iconScale = MGLStyleValue(rawValue: 0.5)
- layer.text = MGLStyleValue(rawValue: "{name}")
- layer.textTranslation = MGLStyleValue(rawValue: NSValue(cgVector: CGVector(dx: 10, dy: 0)))
- layer.textJustification = MGLStyleValue(rawValue: NSValue(mglTextJustification: .left))
- layer.textAnchor = MGLStyleValue(rawValue: NSValue(mglTextAnchor: .left))
+ layer.iconImageName = NSExpression(forConstantValue: "coffee")
+ layer.iconScale = NSExpression(forConstantValue: 0.5)
+ layer.text = NSExpression(forKeyPath: "name")
+ layer.textTranslation = NSExpression(forConstantValue: NSValue(cgVector: CGVector(dx: 10, dy: 0)))
+ layer.textJustification = NSExpression(forConstantValue: "left")
+ layer.textAnchor = NSExpression(forConstantValue: "left")
  layer.predicate = NSPredicate(format: "%K == %@", "venue-type", "coffee")
  mapView.style?.addLayer(layer)
  ```
@@ -369,9 +368,8 @@ MGL_EXPORT
  If true, the icon will be visible even if it collides with other previously
  drawn symbols.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing `NO`. Set this property to `nil` to reset it to
- the default value.
+ The default value of this property is an expression that evaluates to `NO`. Set
+ this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
@@ -380,51 +378,62 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-icon-allow-overlap"><code>icon-allow-overlap</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ * Constant Boolean values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconAllowsOverlap;
+@property (nonatomic, null_resettable) NSExpression *iconAllowsOverlap;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconAllowOverlap __attribute__((unavailable("Use iconAllowsOverlap instead.")));
+@property (nonatomic, null_resettable) NSExpression *iconAllowOverlap __attribute__((unavailable("Use iconAllowsOverlap instead.")));
 
 /**
  Part of the icon placed closest to the anchor.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLIconAnchorCenter`. Set this property to `nil`
- to reset it to the default value.
+ The default value of this property is an expression that evaluates to `center`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconAnchor;
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLIconAnchor` values
+ * Any of the following constant string values:
+   * `center`: The center of the icon is placed closest to the anchor.
+   * `left`: The left side of the icon is placed closest to the anchor.
+   * `right`: The right side of the icon is placed closest to the anchor.
+   * `top`: The top of the icon is placed closest to the anchor.
+   * `bottom`: The bottom of the icon is placed closest to the anchor.
+   * `top-left`: The top left corner of the icon is placed closest to the
+ anchor.
+   * `top-right`: The top right corner of the icon is placed closest to the
+ anchor.
+   * `bottom-left`: The bottom left corner of the icon is placed closest to the
+ anchor.
+   * `bottom-right`: The bottom right corner of the icon is placed closest to
+ the anchor.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
+ */
+@property (nonatomic, null_resettable) NSExpression *iconAnchor;
 
 /**
  If true, other symbols can be visible even if they collide with the icon.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing `NO`. Set this property to `nil` to reset it to
- the default value.
+ The default value of this property is an expression that evaluates to `NO`. Set
+ this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
@@ -433,16 +442,22 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-icon-ignore-placement"><code>icon-ignore-placement</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant Boolean values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconIgnoresPlacement;
+@property (nonatomic, null_resettable) NSExpression *iconIgnoresPlacement;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconIgnorePlacement __attribute__((unavailable("Use iconIgnoresPlacement instead.")));
+@property (nonatomic, null_resettable) NSExpression *iconIgnorePlacement __attribute__((unavailable("Use iconIgnoresPlacement instead.")));
 
 /**
  Name of image in sprite to use for drawing an image background. Within literal
@@ -455,103 +470,87 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-icon-image"><code>icon-image</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant string values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSString *> *iconImageName;
+@property (nonatomic, null_resettable) NSExpression *iconImageName;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSString *> *iconImage __attribute__((unavailable("Use iconImageName instead.")));
+@property (nonatomic, null_resettable) NSExpression *iconImage __attribute__((unavailable("Use iconImageName instead.")));
 
 #if TARGET_OS_IPHONE
 /**
  Offset distance of icon from its anchor.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 rightward and 0
  downward. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconOffset;
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
+ */
+@property (nonatomic, null_resettable) NSExpression *iconOffset;
 #else
 /**
  Offset distance of icon from its anchor.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 rightward and 0
  upward. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconOffset;
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
+ */
+@property (nonatomic, null_resettable) NSExpression *iconOffset;
 #endif
 
 /**
  If true, text will display without their corresponding icons when the icon
  collides with other symbols and the text does not.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing `NO`. Set this property to `nil` to reset it to
- the default value.
+ The default value of this property is an expression that evaluates to `NO`. Set
+ this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`, and
  `text` is non-`nil`. Otherwise, it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant Boolean values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable, getter=isIconOptional) MGLStyleValue<NSNumber *> *iconOptional;
+@property (nonatomic, null_resettable, getter=isIconOptional) NSExpression *iconOptional;
 
 /**
  Size of the additional area around the icon bounding box used for detecting
@@ -559,48 +558,59 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `2`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `2`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconPadding;
+@property (nonatomic, null_resettable) NSExpression *iconPadding;
 
 /**
  Orientation of icon when map is pitched.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLIconPitchAlignmentAuto`. Set this property to
- `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `auto`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ * Constant `MGLIconPitchAlignment` values
+ * Any of the following constant string values:
+   * `map`: The icon is aligned to the plane of the map.
+   * `viewport`: The icon is aligned to the plane of the viewport.
+   * `auto`: Automatically matches the value of `icon-rotation-alignment`.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconPitchAlignment;
+@property (nonatomic, null_resettable) NSExpression *iconPitchAlignment;
 
 /**
  Rotates the icon clockwise.
  
  This property is measured in degrees.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
@@ -609,45 +619,51 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-icon-rotate"><code>icon-rotate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconRotation;
+@property (nonatomic, null_resettable) NSExpression *iconRotation;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconRotate __attribute__((unavailable("Use iconRotation instead.")));
+@property (nonatomic, null_resettable) NSExpression *iconRotate __attribute__((unavailable("Use iconRotation instead.")));
 
 /**
  In combination with `symbolPlacement`, determines the rotation behavior of
  icons.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLIconRotationAlignmentAuto`. Set this property
- to `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `auto`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLIconRotationAlignment` values
+ * Any of the following constant string values:
+   * `map`: When `symbol-placement` is set to `point`, aligns icons east-west.
+ When `symbol-placement` is set to `line`, aligns icon x-axes with the line.
+   * `viewport`: Produces icons whose x-axes are aligned with the x-axis of the
+ viewport, regardless of the value of `symbol-placement`.
+   * `auto`: When `symbol-placement` is set to `point`, this is equivalent to
+ `viewport`. When `symbol-placement` is set to `line`, this is equivalent to
+ `map`.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconRotationAlignment;
+@property (nonatomic, null_resettable) NSExpression *iconRotationAlignment;
 
 /**
  Scales the original size of the icon by the provided factor. The new point size
@@ -656,9 +672,8 @@ MGL_EXPORT
  
  This property is measured in factor of the original icon sizes.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `1`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
@@ -667,44 +682,49 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-icon-size"><code>icon-size</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconScale;
+@property (nonatomic, null_resettable) NSExpression *iconScale;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconSize __attribute__((unavailable("Use iconScale instead.")));
+@property (nonatomic, null_resettable) NSExpression *iconSize __attribute__((unavailable("Use iconScale instead.")));
 
 /**
  Scales the icon to fit around the associated text.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLIconTextFitNone`. Set this property to `nil` to
- reset it to the default value.
+ The default value of this property is an expression that evaluates to `none`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`, and
  `text` is non-`nil`. Otherwise, it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ * Constant `MGLIconTextFit` values
+ * Any of the following constant string values:
+   * `none`: The icon is displayed at its intrinsic aspect ratio.
+   * `width`: The icon is scaled in the x-dimension to fit the width of the
+ text.
+   * `height`: The icon is scaled in the y-dimension to fit the height of the
+ text.
+   * `both`: The icon is scaled in both x- and y-dimensions.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconTextFit;
+@property (nonatomic, null_resettable) NSExpression *iconTextFit;
 
 #if TARGET_OS_IPHONE
 /**
@@ -712,142 +732,160 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing `UIEdgeInsetsZero`. Set this property to `nil` to
  reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`, and
- `text` is non-`nil`, and `iconTextFit` is set to an `MGLStyleValue` object
- containing an `NSValue` object containing `MGLIconTextFitBoth`,
- `MGLIconTextFitWidth`, or `MGLIconTextFitHeight`. Otherwise, it is ignored.
+ `text` is non-`nil`, and `iconTextFit` is set to an expression that evaluates
+ to `MGLIconTextFitBoth`, `MGLIconTextFitWidth`, or `MGLIconTextFitHeight`.
+ Otherwise, it is ignored.
+ 
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant `UIEdgeInsets` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconTextFitPadding;
+@property (nonatomic, null_resettable) NSExpression *iconTextFitPadding;
 #else
 /**
  Size of the additional area added to dimensions determined by `iconTextFit`.
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing `NSEdgeInsetsZero`. Set this property to `nil` to
  reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`, and
- `text` is non-`nil`, and `iconTextFit` is set to an `MGLStyleValue` object
- containing an `NSValue` object containing `MGLIconTextFitBoth`,
- `MGLIconTextFitWidth`, or `MGLIconTextFitHeight`. Otherwise, it is ignored.
+ `text` is non-`nil`, and `iconTextFit` is set to an expression that evaluates
+ to `MGLIconTextFitBoth`, `MGLIconTextFitWidth`, or `MGLIconTextFitHeight`.
+ Otherwise, it is ignored.
+ 
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant `NSEdgeInsets` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconTextFitPadding;
+@property (nonatomic, null_resettable) NSExpression *iconTextFitPadding;
 #endif
 
 /**
  If true, the icon may be flipped to prevent it from being rendered upside-down.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing `NO`. Set this property to `nil` to reset it to
- the default value.
+ The default value of this property is an expression that evaluates to `NO`. Set
+ this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`, and
- `iconRotationAlignment` is set to an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLIconRotationAlignmentMap`, and
- `symbolPlacement` is set to an `MGLStyleValue` object containing an `NSValue`
- object containing `MGLSymbolPlacementLine`. Otherwise, it is ignored.
+ `iconRotationAlignment` is set to an expression that evaluates to `map`, and
+ `symbolPlacement` is set to an expression that evaluates to `line`. Otherwise,
+ it is ignored.
  
  This attribute corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-icon-keep-upright"><code>icon-keep-upright</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ * Constant Boolean values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *keepsIconUpright;
+@property (nonatomic, null_resettable) NSExpression *keepsIconUpright;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconKeepUpright __attribute__((unavailable("Use keepsIconUpright instead.")));
+@property (nonatomic, null_resettable) NSExpression *iconKeepUpright __attribute__((unavailable("Use keepsIconUpright instead.")));
 
 /**
  If true, the text may be flipped vertically to prevent it from being rendered
  upside-down.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing `YES`. Set this property to `nil` to reset it to
- the default value.
+ The default value of this property is an expression that evaluates to `YES`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`, and
- `textRotationAlignment` is set to an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLTextRotationAlignmentMap`, and
- `symbolPlacement` is set to an `MGLStyleValue` object containing an `NSValue`
- object containing `MGLSymbolPlacementLine`. Otherwise, it is ignored.
+ `textRotationAlignment` is set to an expression that evaluates to `map`, and
+ `symbolPlacement` is set to an expression that evaluates to `line`. Otherwise,
+ it is ignored.
  
  This attribute corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-text-keep-upright"><code>text-keep-upright</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant Boolean values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *keepsTextUpright;
+@property (nonatomic, null_resettable) NSExpression *keepsTextUpright;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textKeepUpright __attribute__((unavailable("Use keepsTextUpright instead.")));
+@property (nonatomic, null_resettable) NSExpression *textKeepUpright __attribute__((unavailable("Use keepsTextUpright instead.")));
 
 /**
  Maximum angle change between adjacent characters.
  
  This property is measured in degrees.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `45`. Set this property to `nil` to
- reset it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `45`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`, and
- `symbolPlacement` is set to an `MGLStyleValue` object containing an `NSValue`
- object containing `MGLSymbolPlacementLine`. Otherwise, it is ignored.
+ `symbolPlacement` is set to an expression that evaluates to `line`. Otherwise,
+ it is ignored.
  
  This attribute corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-text-max-angle"><code>text-max-angle</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *maximumTextAngle;
+@property (nonatomic, null_resettable) NSExpression *maximumTextAngle;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textMaxAngle __attribute__((unavailable("Use maximumTextAngle instead.")));
+@property (nonatomic, null_resettable) NSExpression *textMaxAngle __attribute__((unavailable("Use maximumTextAngle instead.")));
 
 /**
  The maximum line width for text wrapping.
  
  This property is measured in ems.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `10`. Set this property to `nil` to
- reset it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `10`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
@@ -856,26 +894,19 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-text-max-width"><code>text-max-width</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *maximumTextWidth;
+@property (nonatomic, null_resettable) NSExpression *maximumTextWidth;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textMaxWidth __attribute__((unavailable("Use maximumTextWidth instead.")));
+@property (nonatomic, null_resettable) NSExpression *textMaxWidth __attribute__((unavailable("Use maximumTextWidth instead.")));
 
 /**
  If true, the symbols will not cross tile edges to avoid mutual collisions.
@@ -883,61 +914,77 @@ MGL_EXPORT
  prevent collisions, or if it is a point symbol layer placed after a line symbol
  layer.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing `NO`. Set this property to `nil` to reset it to
- the default value.
+ The default value of this property is an expression that evaluates to `NO`. Set
+ this property to `nil` to reset it to the default value.
  
  This attribute corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-symbol-avoid-edges"><code>symbol-avoid-edges</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant Boolean values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *symbolAvoidsEdges;
+@property (nonatomic, null_resettable) NSExpression *symbolAvoidsEdges;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *symbolAvoidEdges __attribute__((unavailable("Use symbolAvoidsEdges instead.")));
+@property (nonatomic, null_resettable) NSExpression *symbolAvoidEdges __attribute__((unavailable("Use symbolAvoidsEdges instead.")));
 
 /**
  Label placement relative to its geometry.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLSymbolPlacementPoint`. Set this property to
- `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `point`.
+ Set this property to `nil` to reset it to the default value.
+ 
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant `MGLSymbolPlacement` values
+ * Any of the following constant string values:
+   * `point`: The label is placed at the point where the geometry is located.
+   * `line`: The label is placed along the line of the geometry. Can only be
+ used on `LineString` and `Polygon` geometries.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *symbolPlacement;
+@property (nonatomic, null_resettable) NSExpression *symbolPlacement;
 
 /**
  Distance between two symbol anchors.
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `250`. Set this property to `nil` to
- reset it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `250`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `symbolPlacement` is set to an
- `MGLStyleValue` object containing an `NSValue` object containing
- `MGLSymbolPlacementLine`. Otherwise, it is ignored.
+ expression that evaluates to `line`. Otherwise, it is ignored.
+ 
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *symbolSpacing;
+@property (nonatomic, null_resettable) NSExpression *symbolSpacing;
 
 /**
  Value to use for a text label. Within literal values, attribute names enclosed
@@ -945,41 +992,33 @@ MGL_EXPORT
  attribute. Expressions do not support this syntax; for equivalent functionality
  in expressions, use `stringByAppendingString:` and key path expressions.
  
- The default value of this property is an `MGLStyleValue` object containing the
- empty string. Set this property to `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to the empty
+ string. Set this property to `nil` to reset it to the default value.
  
  This attribute corresponds to the <a
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-text-field"><code>text-field</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant string values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSString *> *text;
+@property (nonatomic, null_resettable) NSExpression *text;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSString *> *textField __attribute__((unavailable("Use text instead.")));
+@property (nonatomic, null_resettable) NSExpression *textField __attribute__((unavailable("Use text instead.")));
 
 /**
  If true, the text will be visible even if it collides with other previously
  drawn symbols.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing `NO`. Set this property to `nil` to reset it to
- the default value.
+ The default value of this property is an expression that evaluates to `NO`. Set
+ this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
@@ -988,44 +1027,56 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-text-allow-overlap"><code>text-allow-overlap</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant Boolean values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textAllowsOverlap;
+@property (nonatomic, null_resettable) NSExpression *textAllowsOverlap;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textAllowOverlap __attribute__((unavailable("Use textAllowsOverlap instead.")));
+@property (nonatomic, null_resettable) NSExpression *textAllowOverlap __attribute__((unavailable("Use textAllowsOverlap instead.")));
 
 /**
  Part of the text placed closest to the anchor.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLTextAnchorCenter`. Set this property to `nil`
- to reset it to the default value.
+ The default value of this property is an expression that evaluates to `center`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textAnchor;
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLTextAnchor` values
+ * Any of the following constant string values:
+   * `center`: The center of the text is placed closest to the anchor.
+   * `left`: The left side of the text is placed closest to the anchor.
+   * `right`: The right side of the text is placed closest to the anchor.
+   * `top`: The top of the text is placed closest to the anchor.
+   * `bottom`: The bottom of the text is placed closest to the anchor.
+   * `top-left`: The top left corner of the text is placed closest to the
+ anchor.
+   * `top-right`: The top right corner of the text is placed closest to the
+ anchor.
+   * `bottom-left`: The bottom left corner of the text is placed closest to the
+ anchor.
+   * `bottom-right`: The bottom right corner of the text is placed closest to
+ the anchor.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
+ */
+@property (nonatomic, null_resettable) NSExpression *textAnchor;
 
 /**
  An array of font face names used to display the text.
@@ -1040,9 +1091,9 @@ MGL_EXPORT
  the text, if the first font lacks a glyph for the character, the next font is
  applied as a fallback, and so on.
  
- The default value of this property is an `MGLStyleValue` object containing the
- array `Open Sans Regular`, `Arial Unicode MS Regular`. Set this property to
- `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to the array
+ `Open Sans Regular`, `Arial Unicode MS Regular`. Set this property to `nil` to
+ reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
@@ -1051,35 +1102,27 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-text-font"><code>text-font</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant array values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSArray<NSString *> *> *textFontNames;
+@property (nonatomic, null_resettable) NSExpression *textFontNames;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSArray<NSString *> *> *textFont __attribute__((unavailable("Use textFontNames instead.")));
+@property (nonatomic, null_resettable) NSExpression *textFont __attribute__((unavailable("Use textFontNames instead.")));
 
 /**
  Font size.
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `16`. Set this property to `nil` to
- reset it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `16`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
@@ -1088,33 +1131,25 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-text-size"><code>text-size</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textFontSize;
+@property (nonatomic, null_resettable) NSExpression *textFontSize;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textSize __attribute__((unavailable("Use textFontSize instead.")));
+@property (nonatomic, null_resettable) NSExpression *textSize __attribute__((unavailable("Use textFontSize instead.")));
 
 /**
  If true, other symbols can be visible even if they collide with the text.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing `NO`. Set this property to `nil` to reset it to
- the default value.
+ The default value of this property is an expression that evaluates to `NO`. Set
+ this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
@@ -1123,23 +1158,28 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-text-ignore-placement"><code>text-ignore-placement</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant Boolean values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textIgnoresPlacement;
+@property (nonatomic, null_resettable) NSExpression *textIgnoresPlacement;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textIgnorePlacement __attribute__((unavailable("Use textIgnoresPlacement instead.")));
+@property (nonatomic, null_resettable) NSExpression *textIgnorePlacement __attribute__((unavailable("Use textIgnoresPlacement instead.")));
 
 /**
  Text justification options.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLTextJustificationCenter`. Set this property to
- `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `center`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
@@ -1148,77 +1188,69 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-text-justify"><code>text-justify</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant `MGLTextJustification` values
+ * Any of the following constant string values:
+   * `left`: The text is aligned to the left.
+   * `center`: The text is centered.
+   * `right`: The text is aligned to the right.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textJustification;
+@property (nonatomic, null_resettable) NSExpression *textJustification;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textJustify __attribute__((unavailable("Use textJustification instead.")));
+@property (nonatomic, null_resettable) NSExpression *textJustify __attribute__((unavailable("Use textJustification instead.")));
 
 /**
  Text tracking amount.
  
  This property is measured in ems.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textLetterSpacing;
+@property (nonatomic, null_resettable) NSExpression *textLetterSpacing;
 
 /**
  Text leading value for multi-line text.
  
  This property is measured in ems.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1.2`. Set this property to `nil` to
- reset it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `1.2`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textLineHeight;
+@property (nonatomic, null_resettable) NSExpression *textLineHeight;
 
 #if TARGET_OS_IPHONE
 /**
@@ -1226,80 +1258,71 @@ MGL_EXPORT
  
  This property is measured in ems.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 ems rightward and 0
  ems downward. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textOffset;
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
+ */
+@property (nonatomic, null_resettable) NSExpression *textOffset;
 #else
 /**
  Offset distance of text from its anchor.
  
  This property is measured in ems.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 ems rightward and 0
  ems upward. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textOffset;
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
+ */
+@property (nonatomic, null_resettable) NSExpression *textOffset;
 #endif
 
 /**
  If true, icons will display without their corresponding text when the text
  collides with other symbols and the icon does not.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing `NO`. Set this property to `nil` to reset it to
- the default value.
+ The default value of this property is an expression that evaluates to `NO`. Set
+ this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`, and
  `iconImageName` is non-`nil`. Otherwise, it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant Boolean values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable, getter=isTextOptional) MGLStyleValue<NSNumber *> *textOptional;
+@property (nonatomic, null_resettable, getter=isTextOptional) NSExpression *textOptional;
 
 /**
  Size of the additional area around the text bounding box used for detecting
@@ -1307,48 +1330,59 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `2`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `2`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textPadding;
+@property (nonatomic, null_resettable) NSExpression *textPadding;
 
 /**
  Orientation of text when map is pitched.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLTextPitchAlignmentAuto`. Set this property to
- `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `auto`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLTextPitchAlignment` values
+ * Any of the following constant string values:
+   * `map`: The text is aligned to the plane of the map.
+   * `viewport`: The text is aligned to the plane of the viewport.
+   * `auto`: Automatically matches the value of `text-rotation-alignment`.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textPitchAlignment;
+@property (nonatomic, null_resettable) NSExpression *textPitchAlignment;
 
 /**
  Rotates the text clockwise.
  
  This property is measured in degrees.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
@@ -1357,135 +1391,99 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#layout-symbol-text-rotate"><code>text-rotate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textRotation;
+@property (nonatomic, null_resettable) NSExpression *textRotation;
 
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textRotate __attribute__((unavailable("Use textRotation instead.")));
+@property (nonatomic, null_resettable) NSExpression *textRotate __attribute__((unavailable("Use textRotation instead.")));
 
 /**
  In combination with `symbolPlacement`, determines the rotation behavior of the
  individual glyphs forming the text.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLTextRotationAlignmentAuto`. Set this property
- to `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `auto`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLTextRotationAlignment` values
+ * Any of the following constant string values:
+   * `map`: When `symbol-placement` is set to `point`, aligns text east-west.
+ When `symbol-placement` is set to `line`, aligns text x-axes with the line.
+   * `viewport`: Produces glyphs whose x-axes are aligned with the x-axis of the
+ viewport, regardless of the value of `symbol-placement`.
+   * `auto`: When `symbol-placement` is set to `point`, this is equivalent to
+ `viewport`. When `symbol-placement` is set to `line`, this is equivalent to
+ `map`.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textRotationAlignment;
+@property (nonatomic, null_resettable) NSExpression *textRotationAlignment;
 
 /**
  Specifies how to capitalize text.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLTextTransformNone`. Set this property to `nil`
- to reset it to the default value.
+ The default value of this property is an expression that evaluates to `none`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant `MGLTextTransform` values
+ * Any of the following constant string values:
+   * `none`: The text is not altered.
+   * `uppercase`: Forces all letters to be displayed in uppercase.
+   * `lowercase`: Forces all letters to be displayed in lowercase.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textTransform;
+@property (nonatomic, null_resettable) NSExpression *textTransform;
 
 #pragma mark - Accessing the Paint Attributes
 
-#if TARGET_OS_IPHONE
 /**
  The tint color to apply to the icon. The `iconImageName` property must be set
  to a template image.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.blackColor`. Set this property to `nil` to reset it to the default
  value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *iconColor;
-#else
-/**
- The tint color to apply to the icon. The `iconImageName` property must be set
- to a template image.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.blackColor`. Set this property to `nil` to reset it to the default
- value.
- 
- This property is only applied to the style if `iconImageName` is non-`nil`.
- Otherwise, it is ignored.
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *iconColor;
-#endif
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
+ */
+@property (nonatomic, null_resettable) NSExpression *iconColor;
 
 /**
  The transition affecting any changes to this layer’s `iconColor` property.
@@ -1499,30 +1497,22 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconHaloBlur;
+@property (nonatomic, null_resettable) NSExpression *iconHaloBlur;
 
 /**
  The transition affecting any changes to this layer’s `iconHaloBlur` property.
@@ -1531,65 +1521,27 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition iconHaloBlurTransition;
 
-#if TARGET_OS_IPHONE
 /**
  The color of the icon’s halo. The `iconImageName` property must be set to a
  template image.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.clearColor`. Set this property to `nil` to reset it to the default
  value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *iconHaloColor;
-#else
-/**
- The color of the icon’s halo. The `iconImageName` property must be set to a
- template image.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.clearColor`. Set this property to `nil` to reset it to the default
- value.
- 
- This property is only applied to the style if `iconImageName` is non-`nil`.
- Otherwise, it is ignored.
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *iconHaloColor;
-#endif
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
+ */
+@property (nonatomic, null_resettable) NSExpression *iconHaloColor;
 
 /**
  The transition affecting any changes to this layer’s `iconHaloColor` property.
@@ -1603,30 +1555,22 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconHaloWidth;
+@property (nonatomic, null_resettable) NSExpression *iconHaloWidth;
 
 /**
  The transition affecting any changes to this layer’s `iconHaloWidth` property.
@@ -1638,30 +1582,22 @@ MGL_EXPORT
 /**
  The opacity at which the icon will be drawn.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `1`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`.
  Otherwise, it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *iconOpacity;
+@property (nonatomic, null_resettable) NSExpression *iconOpacity;
 
 /**
  The transition affecting any changes to this layer’s `iconOpacity` property.
@@ -1676,7 +1612,7 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 points rightward and 0
  points downward. Set this property to `nil` to reset it to the default value.
  
@@ -1687,21 +1623,25 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-icon-translate"><code>icon-translate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconTranslation;
+@property (nonatomic, null_resettable) NSExpression *iconTranslation;
 #else
 /**
  Distance that the icon's anchor is moved from its original placement.
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 points rightward and 0
  points upward. Set this property to `nil` to reset it to the default value.
  
@@ -1712,14 +1652,18 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-icon-translate"><code>icon-translate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconTranslation;
+@property (nonatomic, null_resettable) NSExpression *iconTranslation;
 #endif
 
 /**
@@ -1729,14 +1673,13 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition iconTranslationTransition;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconTranslate __attribute__((unavailable("Use iconTranslation instead.")));
+@property (nonatomic, null_resettable) NSExpression *iconTranslate __attribute__((unavailable("Use iconTranslation instead.")));
 
 /**
  Controls the frame of reference for `iconTranslation`.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLIconTranslationAnchorMap`. Set this property to
- `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `map`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `iconImageName` is non-`nil`, and
  `iconTranslation` is non-`nil`. Otherwise, it is ignored.
@@ -1745,73 +1688,45 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-icon-translate-anchor"><code>icon-translate-anchor</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLIconTranslationAnchor` values
+ * Any of the following constant string values:
+   * `map`: Icons are translated relative to the map.
+   * `viewport`: Icons are translated relative to the viewport.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconTranslationAnchor;
+@property (nonatomic, null_resettable) NSExpression *iconTranslationAnchor;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *iconTranslateAnchor __attribute__((unavailable("Use iconTranslationAnchor instead.")));
+@property (nonatomic, null_resettable) NSExpression *iconTranslateAnchor __attribute__((unavailable("Use iconTranslationAnchor instead.")));
 
-#if TARGET_OS_IPHONE
 /**
  The color with which the text will be drawn.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.blackColor`. Set this property to `nil` to reset it to the default
  value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *textColor;
-#else
-/**
- The color with which the text will be drawn.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.blackColor`. Set this property to `nil` to reset it to the default
- value.
- 
- This property is only applied to the style if `text` is non-`nil`. Otherwise,
- it is ignored.
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *textColor;
-#endif
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
+ */
+@property (nonatomic, null_resettable) NSExpression *textColor;
 
 /**
  The transition affecting any changes to this layer’s `textColor` property.
@@ -1825,30 +1740,22 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textHaloBlur;
+@property (nonatomic, null_resettable) NSExpression *textHaloBlur;
 
 /**
  The transition affecting any changes to this layer’s `textHaloBlur` property.
@@ -1857,63 +1764,26 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition textHaloBlurTransition;
 
-#if TARGET_OS_IPHONE
 /**
  The color of the text's halo, which helps it stand out from backgrounds.
  
- The default value of this property is an `MGLStyleValue` object containing
+ The default value of this property is an expression that evaluates to
  `UIColor.clearColor`. Set this property to `nil` to reset it to the default
  value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<UIColor *> *textHaloColor;
-#else
-/**
- The color of the text's halo, which helps it stand out from backgrounds.
- 
- The default value of this property is an `MGLStyleValue` object containing
- `NSColor.clearColor`. Set this property to `nil` to reset it to the default
- value.
- 
- This property is only applied to the style if `text` is non-`nil`. Otherwise,
- it is ignored.
+ You can set this property to an expression containing any of the following:
  
- You can set this property to an instance of:
- 
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
- */
-@property (nonatomic, null_resettable) MGLStyleValue<NSColor *> *textHaloColor;
-#endif
+ * Constant `UIColor` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
+ */
+@property (nonatomic, null_resettable) NSExpression *textHaloColor;
 
 /**
  The transition affecting any changes to this layer’s `textHaloColor` property.
@@ -1928,30 +1798,22 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `0`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `0`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textHaloWidth;
+@property (nonatomic, null_resettable) NSExpression *textHaloWidth;
 
 /**
  The transition affecting any changes to this layer’s `textHaloWidth` property.
@@ -1963,30 +1825,22 @@ MGL_EXPORT
 /**
  The opacity at which the text will be drawn.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSNumber` object containing the float `1`. Set this property to `nil` to reset
- it to the default value.
+ The default value of this property is an expression that evaluates to the float
+ `1`. Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`. Otherwise,
  it is ignored.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
- * `MGLSourceStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
-   * `MGLInterpolationModeIdentity`
- * `MGLCompositeStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
-   * `MGLInterpolationModeCategorical`
+ * Constant numeric values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable and/or
+ feature attributes
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSNumber *> *textOpacity;
+@property (nonatomic, null_resettable) NSExpression *textOpacity;
 
 /**
  The transition affecting any changes to this layer’s `textOpacity` property.
@@ -2001,7 +1855,7 @@ MGL_EXPORT
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 points rightward and 0
  points downward. Set this property to `nil` to reset it to the default value.
  
@@ -2012,21 +1866,25 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-text-translate"><code>text-translate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textTranslation;
+@property (nonatomic, null_resettable) NSExpression *textTranslation;
 #else
 /**
  Distance that the text's anchor is moved from its original placement.
  
  This property is measured in points.
  
- The default value of this property is an `MGLStyleValue` object containing an
+ The default value of this property is an expression that evaluates to an
  `NSValue` object containing a `CGVector` struct set to 0 points rightward and 0
  points upward. Set this property to `nil` to reset it to the default value.
  
@@ -2037,14 +1895,18 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-text-translate"><code>text-translate</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `CGVector` values
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Interpolation and step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of:
-   * `MGLInterpolationModeExponential`
-   * `MGLInterpolationModeInterval`
+ This property does not support applying interpolation or step functions to
+ feature attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textTranslation;
+@property (nonatomic, null_resettable) NSExpression *textTranslation;
 #endif
 
 /**
@@ -2054,14 +1916,13 @@ MGL_EXPORT
 */
 @property (nonatomic) MGLTransition textTranslationTransition;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textTranslate __attribute__((unavailable("Use textTranslation instead.")));
+@property (nonatomic, null_resettable) NSExpression *textTranslate __attribute__((unavailable("Use textTranslation instead.")));
 
 /**
  Controls the frame of reference for `textTranslation`.
  
- The default value of this property is an `MGLStyleValue` object containing an
- `NSValue` object containing `MGLTextTranslationAnchorMap`. Set this property to
- `nil` to reset it to the default value.
+ The default value of this property is an expression that evaluates to `map`.
+ Set this property to `nil` to reset it to the default value.
  
  This property is only applied to the style if `text` is non-`nil`, and
  `textTranslation` is non-`nil`. Otherwise, it is ignored.
@@ -2070,15 +1931,24 @@ MGL_EXPORT
  href="https://www.mapbox.com/mapbox-gl-style-spec/#paint-text-translate-anchor"><code>text-translate-anchor</code></a>
  layout property in the Mapbox Style Specification.
  
- You can set this property to an instance of:
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLTextTranslationAnchor` values
+ * Any of the following constant string values:
+   * `map`: The text is translated relative to the map.
+   * `viewport`: The text is translated relative to the viewport.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
  
- * `MGLConstantStyleValue`
- * `MGLCameraStyleFunction` with an interpolation mode of
- `MGLInterpolationModeInterval`
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
  */
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textTranslationAnchor;
+@property (nonatomic, null_resettable) NSExpression *textTranslationAnchor;
 
-@property (nonatomic, null_resettable) MGLStyleValue<NSValue *> *textTranslateAnchor __attribute__((unavailable("Use textTranslationAnchor instead.")));
+@property (nonatomic, null_resettable) NSExpression *textTranslateAnchor __attribute__((unavailable("Use textTranslationAnchor instead.")));
 
 @end
 
diff --git a/platform/darwin/src/MGLSymbolStyleLayer.mm b/platform/darwin/src/MGLSymbolStyleLayer.mm
index 3f206aac19..24d6643e6c 100644
--- a/platform/darwin/src/MGLSymbolStyleLayer.mm
+++ b/platform/darwin/src/MGLSymbolStyleLayer.mm
@@ -154,754 +154,754 @@ namespace mbgl {
 
 #pragma mark - Accessing the Layout Attributes
 
-- (void)setIconAllowsOverlap:(MGLStyleValue<NSNumber *> *)iconAllowsOverlap {
+- (void)setIconAllowsOverlap:(NSExpression *)iconAllowsOverlap {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue(iconAllowsOverlap);
+    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<bool>>(iconAllowsOverlap);
     self.rawLayer->setIconAllowOverlap(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)iconAllowsOverlap {
+- (NSExpression *)iconAllowsOverlap {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconAllowOverlap();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(self.rawLayer->getDefaultIconAllowOverlap());
+        propertyValue = self.rawLayer->getDefaultIconAllowOverlap();
     }
-    return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<bool, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setIconAllowOverlap:(MGLStyleValue<NSNumber *> *)iconAllowOverlap {
+- (void)setIconAllowOverlap:(NSExpression *)iconAllowOverlap {
 }
 
-- (MGLStyleValue<NSNumber *> *)iconAllowOverlap {
+- (NSExpression *)iconAllowOverlap {
     return self.iconAllowsOverlap;
 }
 
-- (void)setIconAnchor:(MGLStyleValue<NSValue *> *)iconAnchor {
+- (void)setIconAnchor:(NSExpression *)iconAnchor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLIconAnchor>().toDataDrivenPropertyValue(iconAnchor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLIconAnchor>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::style::SymbolAnchorType>>(iconAnchor);
     self.rawLayer->setIconAnchor(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)iconAnchor {
+- (NSExpression *)iconAnchor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconAnchor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLIconAnchor>().toDataDrivenStyleValue(self.rawLayer->getDefaultIconAnchor());
+        propertyValue = self.rawLayer->getDefaultIconAnchor();
     }
-    return MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLIconAnchor>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLIconAnchor>().toExpression(propertyValue);
 }
 
-- (void)setIconIgnoresPlacement:(MGLStyleValue<NSNumber *> *)iconIgnoresPlacement {
+- (void)setIconIgnoresPlacement:(NSExpression *)iconIgnoresPlacement {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue(iconIgnoresPlacement);
+    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<bool>>(iconIgnoresPlacement);
     self.rawLayer->setIconIgnorePlacement(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)iconIgnoresPlacement {
+- (NSExpression *)iconIgnoresPlacement {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconIgnorePlacement();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(self.rawLayer->getDefaultIconIgnorePlacement());
+        propertyValue = self.rawLayer->getDefaultIconIgnorePlacement();
     }
-    return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<bool, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setIconIgnorePlacement:(MGLStyleValue<NSNumber *> *)iconIgnorePlacement {
+- (void)setIconIgnorePlacement:(NSExpression *)iconIgnorePlacement {
 }
 
-- (MGLStyleValue<NSNumber *> *)iconIgnorePlacement {
+- (NSExpression *)iconIgnorePlacement {
     return self.iconIgnoresPlacement;
 }
 
-- (void)setIconImageName:(MGLStyleValue<NSString *> *)iconImageName {
+- (void)setIconImageName:(NSExpression *)iconImageName {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::string, NSString *>().toDataDrivenPropertyValue(iconImageName);
+    auto mbglValue = MGLStyleValueTransformer<std::string, NSString *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<std::string>>(iconImageName);
     self.rawLayer->setIconImage(mbglValue);
 }
 
-- (MGLStyleValue<NSString *> *)iconImageName {
+- (NSExpression *)iconImageName {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconImage();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::string, NSString *>().toDataDrivenStyleValue(self.rawLayer->getDefaultIconImage());
+        propertyValue = self.rawLayer->getDefaultIconImage();
     }
-    return MGLStyleValueTransformer<std::string, NSString *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::string, NSString *>().toExpression(propertyValue);
 }
 
-- (void)setIconImage:(MGLStyleValue<NSString *> *)iconImage {
+- (void)setIconImage:(NSExpression *)iconImage {
 }
 
-- (MGLStyleValue<NSString *> *)iconImage {
+- (NSExpression *)iconImage {
     return self.iconImageName;
 }
 
-- (void)setIconOffset:(MGLStyleValue<NSValue *> *)iconOffset {
+- (void)setIconOffset:(NSExpression *)iconOffset {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toDataDrivenPropertyValue(iconOffset);
+    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<std::array<float, 2>>>(iconOffset);
     self.rawLayer->setIconOffset(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)iconOffset {
+- (NSExpression *)iconOffset {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconOffset();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toDataDrivenStyleValue(self.rawLayer->getDefaultIconOffset());
+        propertyValue = self.rawLayer->getDefaultIconOffset();
     }
-    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toExpression(propertyValue);
 }
 
-- (void)setIconOptional:(MGLStyleValue<NSNumber *> *)iconOptional {
+- (void)setIconOptional:(NSExpression *)iconOptional {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue(iconOptional);
+    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<bool>>(iconOptional);
     self.rawLayer->setIconOptional(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)isIconOptional {
+- (NSExpression *)isIconOptional {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconOptional();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(self.rawLayer->getDefaultIconOptional());
+        propertyValue = self.rawLayer->getDefaultIconOptional();
     }
-    return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<bool, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setIconPadding:(MGLStyleValue<NSNumber *> *)iconPadding {
+- (void)setIconPadding:(NSExpression *)iconPadding {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(iconPadding);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(iconPadding);
     self.rawLayer->setIconPadding(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)iconPadding {
+- (NSExpression *)iconPadding {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconPadding();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultIconPadding());
+        propertyValue = self.rawLayer->getDefaultIconPadding();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setIconPitchAlignment:(MGLStyleValue<NSValue *> *)iconPitchAlignment {
+- (void)setIconPitchAlignment:(NSExpression *)iconPitchAlignment {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLIconPitchAlignment>().toEnumPropertyValue(iconPitchAlignment);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLIconPitchAlignment>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::AlignmentType>>(iconPitchAlignment);
     self.rawLayer->setIconPitchAlignment(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)iconPitchAlignment {
+- (NSExpression *)iconPitchAlignment {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconPitchAlignment();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLIconPitchAlignment>().toEnumStyleValue(self.rawLayer->getDefaultIconPitchAlignment());
+        propertyValue = self.rawLayer->getDefaultIconPitchAlignment();
     }
-    return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLIconPitchAlignment>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLIconPitchAlignment>().toExpression(propertyValue);
 }
 
-- (void)setIconRotation:(MGLStyleValue<NSNumber *> *)iconRotation {
+- (void)setIconRotation:(NSExpression *)iconRotation {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(iconRotation);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(iconRotation);
     self.rawLayer->setIconRotate(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)iconRotation {
+- (NSExpression *)iconRotation {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconRotate();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultIconRotate());
+        propertyValue = self.rawLayer->getDefaultIconRotate();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setIconRotate:(MGLStyleValue<NSNumber *> *)iconRotate {
+- (void)setIconRotate:(NSExpression *)iconRotate {
 }
 
-- (MGLStyleValue<NSNumber *> *)iconRotate {
+- (NSExpression *)iconRotate {
     return self.iconRotation;
 }
 
-- (void)setIconRotationAlignment:(MGLStyleValue<NSValue *> *)iconRotationAlignment {
+- (void)setIconRotationAlignment:(NSExpression *)iconRotationAlignment {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLIconRotationAlignment>().toEnumPropertyValue(iconRotationAlignment);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLIconRotationAlignment>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::AlignmentType>>(iconRotationAlignment);
     self.rawLayer->setIconRotationAlignment(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)iconRotationAlignment {
+- (NSExpression *)iconRotationAlignment {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconRotationAlignment();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLIconRotationAlignment>().toEnumStyleValue(self.rawLayer->getDefaultIconRotationAlignment());
+        propertyValue = self.rawLayer->getDefaultIconRotationAlignment();
     }
-    return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLIconRotationAlignment>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLIconRotationAlignment>().toExpression(propertyValue);
 }
 
-- (void)setIconScale:(MGLStyleValue<NSNumber *> *)iconScale {
+- (void)setIconScale:(NSExpression *)iconScale {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(iconScale);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(iconScale);
     self.rawLayer->setIconSize(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)iconScale {
+- (NSExpression *)iconScale {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconSize();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultIconSize());
+        propertyValue = self.rawLayer->getDefaultIconSize();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setIconSize:(MGLStyleValue<NSNumber *> *)iconSize {
+- (void)setIconSize:(NSExpression *)iconSize {
 }
 
-- (MGLStyleValue<NSNumber *> *)iconSize {
+- (NSExpression *)iconSize {
     return self.iconScale;
 }
 
-- (void)setIconTextFit:(MGLStyleValue<NSValue *> *)iconTextFit {
+- (void)setIconTextFit:(NSExpression *)iconTextFit {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::IconTextFitType, NSValue *, mbgl::style::IconTextFitType, MGLIconTextFit>().toEnumPropertyValue(iconTextFit);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::IconTextFitType, NSValue *, mbgl::style::IconTextFitType, MGLIconTextFit>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::IconTextFitType>>(iconTextFit);
     self.rawLayer->setIconTextFit(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)iconTextFit {
+- (NSExpression *)iconTextFit {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconTextFit();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::IconTextFitType, NSValue *, mbgl::style::IconTextFitType, MGLIconTextFit>().toEnumStyleValue(self.rawLayer->getDefaultIconTextFit());
+        propertyValue = self.rawLayer->getDefaultIconTextFit();
     }
-    return MGLStyleValueTransformer<mbgl::style::IconTextFitType, NSValue *, mbgl::style::IconTextFitType, MGLIconTextFit>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::IconTextFitType, NSValue *, mbgl::style::IconTextFitType, MGLIconTextFit>().toExpression(propertyValue);
 }
 
-- (void)setIconTextFitPadding:(MGLStyleValue<NSValue *> *)iconTextFitPadding {
+- (void)setIconTextFitPadding:(NSExpression *)iconTextFitPadding {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::array<float, 4>, NSValue *>().toInterpolatablePropertyValue(iconTextFitPadding);
+    auto mbglValue = MGLStyleValueTransformer<std::array<float, 4>, NSValue *>().toPropertyValue<mbgl::style::PropertyValue<std::array<float, 4>>>(iconTextFitPadding);
     self.rawLayer->setIconTextFitPadding(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)iconTextFitPadding {
+- (NSExpression *)iconTextFitPadding {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconTextFitPadding();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::array<float, 4>, NSValue *>().toStyleValue(self.rawLayer->getDefaultIconTextFitPadding());
+        propertyValue = self.rawLayer->getDefaultIconTextFitPadding();
     }
-    return MGLStyleValueTransformer<std::array<float, 4>, NSValue *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::array<float, 4>, NSValue *>().toExpression(propertyValue);
 }
 
-- (void)setKeepsIconUpright:(MGLStyleValue<NSNumber *> *)keepsIconUpright {
+- (void)setKeepsIconUpright:(NSExpression *)keepsIconUpright {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue(keepsIconUpright);
+    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<bool>>(keepsIconUpright);
     self.rawLayer->setIconKeepUpright(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)keepsIconUpright {
+- (NSExpression *)keepsIconUpright {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconKeepUpright();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(self.rawLayer->getDefaultIconKeepUpright());
+        propertyValue = self.rawLayer->getDefaultIconKeepUpright();
     }
-    return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<bool, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setIconKeepUpright:(MGLStyleValue<NSNumber *> *)iconKeepUpright {
+- (void)setIconKeepUpright:(NSExpression *)iconKeepUpright {
 }
 
-- (MGLStyleValue<NSNumber *> *)iconKeepUpright {
+- (NSExpression *)iconKeepUpright {
     return self.keepsIconUpright;
 }
 
-- (void)setKeepsTextUpright:(MGLStyleValue<NSNumber *> *)keepsTextUpright {
+- (void)setKeepsTextUpright:(NSExpression *)keepsTextUpright {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue(keepsTextUpright);
+    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<bool>>(keepsTextUpright);
     self.rawLayer->setTextKeepUpright(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)keepsTextUpright {
+- (NSExpression *)keepsTextUpright {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextKeepUpright();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(self.rawLayer->getDefaultTextKeepUpright());
+        propertyValue = self.rawLayer->getDefaultTextKeepUpright();
     }
-    return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<bool, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setTextKeepUpright:(MGLStyleValue<NSNumber *> *)textKeepUpright {
+- (void)setTextKeepUpright:(NSExpression *)textKeepUpright {
 }
 
-- (MGLStyleValue<NSNumber *> *)textKeepUpright {
+- (NSExpression *)textKeepUpright {
     return self.keepsTextUpright;
 }
 
-- (void)setMaximumTextAngle:(MGLStyleValue<NSNumber *> *)maximumTextAngle {
+- (void)setMaximumTextAngle:(NSExpression *)maximumTextAngle {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(maximumTextAngle);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(maximumTextAngle);
     self.rawLayer->setTextMaxAngle(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)maximumTextAngle {
+- (NSExpression *)maximumTextAngle {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextMaxAngle();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultTextMaxAngle());
+        propertyValue = self.rawLayer->getDefaultTextMaxAngle();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setTextMaxAngle:(MGLStyleValue<NSNumber *> *)textMaxAngle {
+- (void)setTextMaxAngle:(NSExpression *)textMaxAngle {
 }
 
-- (MGLStyleValue<NSNumber *> *)textMaxAngle {
+- (NSExpression *)textMaxAngle {
     return self.maximumTextAngle;
 }
 
-- (void)setMaximumTextWidth:(MGLStyleValue<NSNumber *> *)maximumTextWidth {
+- (void)setMaximumTextWidth:(NSExpression *)maximumTextWidth {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(maximumTextWidth);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(maximumTextWidth);
     self.rawLayer->setTextMaxWidth(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)maximumTextWidth {
+- (NSExpression *)maximumTextWidth {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextMaxWidth();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextMaxWidth());
+        propertyValue = self.rawLayer->getDefaultTextMaxWidth();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setTextMaxWidth:(MGLStyleValue<NSNumber *> *)textMaxWidth {
+- (void)setTextMaxWidth:(NSExpression *)textMaxWidth {
 }
 
-- (MGLStyleValue<NSNumber *> *)textMaxWidth {
+- (NSExpression *)textMaxWidth {
     return self.maximumTextWidth;
 }
 
-- (void)setSymbolAvoidsEdges:(MGLStyleValue<NSNumber *> *)symbolAvoidsEdges {
+- (void)setSymbolAvoidsEdges:(NSExpression *)symbolAvoidsEdges {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue(symbolAvoidsEdges);
+    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<bool>>(symbolAvoidsEdges);
     self.rawLayer->setSymbolAvoidEdges(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)symbolAvoidsEdges {
+- (NSExpression *)symbolAvoidsEdges {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getSymbolAvoidEdges();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(self.rawLayer->getDefaultSymbolAvoidEdges());
+        propertyValue = self.rawLayer->getDefaultSymbolAvoidEdges();
     }
-    return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<bool, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setSymbolAvoidEdges:(MGLStyleValue<NSNumber *> *)symbolAvoidEdges {
+- (void)setSymbolAvoidEdges:(NSExpression *)symbolAvoidEdges {
 }
 
-- (MGLStyleValue<NSNumber *> *)symbolAvoidEdges {
+- (NSExpression *)symbolAvoidEdges {
     return self.symbolAvoidsEdges;
 }
 
-- (void)setSymbolPlacement:(MGLStyleValue<NSValue *> *)symbolPlacement {
+- (void)setSymbolPlacement:(NSExpression *)symbolPlacement {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::SymbolPlacementType, NSValue *, mbgl::style::SymbolPlacementType, MGLSymbolPlacement>().toEnumPropertyValue(symbolPlacement);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::SymbolPlacementType, NSValue *, mbgl::style::SymbolPlacementType, MGLSymbolPlacement>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::SymbolPlacementType>>(symbolPlacement);
     self.rawLayer->setSymbolPlacement(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)symbolPlacement {
+- (NSExpression *)symbolPlacement {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getSymbolPlacement();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::SymbolPlacementType, NSValue *, mbgl::style::SymbolPlacementType, MGLSymbolPlacement>().toEnumStyleValue(self.rawLayer->getDefaultSymbolPlacement());
+        propertyValue = self.rawLayer->getDefaultSymbolPlacement();
     }
-    return MGLStyleValueTransformer<mbgl::style::SymbolPlacementType, NSValue *, mbgl::style::SymbolPlacementType, MGLSymbolPlacement>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::SymbolPlacementType, NSValue *, mbgl::style::SymbolPlacementType, MGLSymbolPlacement>().toExpression(propertyValue);
 }
 
-- (void)setSymbolSpacing:(MGLStyleValue<NSNumber *> *)symbolSpacing {
+- (void)setSymbolSpacing:(NSExpression *)symbolSpacing {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(symbolSpacing);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(symbolSpacing);
     self.rawLayer->setSymbolSpacing(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)symbolSpacing {
+- (NSExpression *)symbolSpacing {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getSymbolSpacing();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultSymbolSpacing());
+        propertyValue = self.rawLayer->getDefaultSymbolSpacing();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setText:(MGLStyleValue<NSString *> *)text {
+- (void)setText:(NSExpression *)text {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::string, NSString *>().toDataDrivenPropertyValue(text);
+    auto mbglValue = MGLStyleValueTransformer<std::string, NSString *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<std::string>>(text);
     self.rawLayer->setTextField(mbglValue);
 }
 
-- (MGLStyleValue<NSString *> *)text {
+- (NSExpression *)text {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextField();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::string, NSString *>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextField());
+        propertyValue = self.rawLayer->getDefaultTextField();
     }
-    return MGLStyleValueTransformer<std::string, NSString *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::string, NSString *>().toExpression(propertyValue);
 }
 
-- (void)setTextField:(MGLStyleValue<NSString *> *)textField {
+- (void)setTextField:(NSExpression *)textField {
 }
 
-- (MGLStyleValue<NSString *> *)textField {
+- (NSExpression *)textField {
     return self.text;
 }
 
-- (void)setTextAllowsOverlap:(MGLStyleValue<NSNumber *> *)textAllowsOverlap {
+- (void)setTextAllowsOverlap:(NSExpression *)textAllowsOverlap {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue(textAllowsOverlap);
+    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<bool>>(textAllowsOverlap);
     self.rawLayer->setTextAllowOverlap(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)textAllowsOverlap {
+- (NSExpression *)textAllowsOverlap {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextAllowOverlap();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(self.rawLayer->getDefaultTextAllowOverlap());
+        propertyValue = self.rawLayer->getDefaultTextAllowOverlap();
     }
-    return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<bool, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setTextAllowOverlap:(MGLStyleValue<NSNumber *> *)textAllowOverlap {
+- (void)setTextAllowOverlap:(NSExpression *)textAllowOverlap {
 }
 
-- (MGLStyleValue<NSNumber *> *)textAllowOverlap {
+- (NSExpression *)textAllowOverlap {
     return self.textAllowsOverlap;
 }
 
-- (void)setTextAnchor:(MGLStyleValue<NSValue *> *)textAnchor {
+- (void)setTextAnchor:(NSExpression *)textAnchor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLTextAnchor>().toDataDrivenPropertyValue(textAnchor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLTextAnchor>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::style::SymbolAnchorType>>(textAnchor);
     self.rawLayer->setTextAnchor(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)textAnchor {
+- (NSExpression *)textAnchor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextAnchor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLTextAnchor>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextAnchor());
+        propertyValue = self.rawLayer->getDefaultTextAnchor();
     }
-    return MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLTextAnchor>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::SymbolAnchorType, NSValue *, mbgl::style::SymbolAnchorType, MGLTextAnchor>().toExpression(propertyValue);
 }
 
-- (void)setTextFontNames:(MGLStyleValue<NSArray<NSString *> *> *)textFontNames {
+- (void)setTextFontNames:(NSExpression *)textFontNames {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::vector<std::string>, NSArray<NSString *> *, std::string>().toDataDrivenPropertyValue(textFontNames);
+    auto mbglValue = MGLStyleValueTransformer<std::vector<std::string>, NSArray<NSString *> *, std::string>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<std::vector<std::string>>>(textFontNames);
     self.rawLayer->setTextFont(mbglValue);
 }
 
-- (MGLStyleValue<NSArray<NSString *> *> *)textFontNames {
+- (NSExpression *)textFontNames {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextFont();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::vector<std::string>, NSArray<NSString *> *, std::string>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextFont());
+        propertyValue = self.rawLayer->getDefaultTextFont();
     }
-    return MGLStyleValueTransformer<std::vector<std::string>, NSArray<NSString *> *, std::string>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::vector<std::string>, NSArray<NSString *> *, std::string>().toExpression(propertyValue);
 }
 
-- (void)setTextFont:(MGLStyleValue<NSArray<NSString *> *> *)textFont {
+- (void)setTextFont:(NSExpression *)textFont {
 }
 
-- (MGLStyleValue<NSArray<NSString *> *> *)textFont {
+- (NSExpression *)textFont {
     return self.textFontNames;
 }
 
-- (void)setTextFontSize:(MGLStyleValue<NSNumber *> *)textFontSize {
+- (void)setTextFontSize:(NSExpression *)textFontSize {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(textFontSize);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(textFontSize);
     self.rawLayer->setTextSize(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)textFontSize {
+- (NSExpression *)textFontSize {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextSize();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextSize());
+        propertyValue = self.rawLayer->getDefaultTextSize();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setTextSize:(MGLStyleValue<NSNumber *> *)textSize {
+- (void)setTextSize:(NSExpression *)textSize {
 }
 
-- (MGLStyleValue<NSNumber *> *)textSize {
+- (NSExpression *)textSize {
     return self.textFontSize;
 }
 
-- (void)setTextIgnoresPlacement:(MGLStyleValue<NSNumber *> *)textIgnoresPlacement {
+- (void)setTextIgnoresPlacement:(NSExpression *)textIgnoresPlacement {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue(textIgnoresPlacement);
+    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<bool>>(textIgnoresPlacement);
     self.rawLayer->setTextIgnorePlacement(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)textIgnoresPlacement {
+- (NSExpression *)textIgnoresPlacement {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextIgnorePlacement();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(self.rawLayer->getDefaultTextIgnorePlacement());
+        propertyValue = self.rawLayer->getDefaultTextIgnorePlacement();
     }
-    return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<bool, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setTextIgnorePlacement:(MGLStyleValue<NSNumber *> *)textIgnorePlacement {
+- (void)setTextIgnorePlacement:(NSExpression *)textIgnorePlacement {
 }
 
-- (MGLStyleValue<NSNumber *> *)textIgnorePlacement {
+- (NSExpression *)textIgnorePlacement {
     return self.textIgnoresPlacement;
 }
 
-- (void)setTextJustification:(MGLStyleValue<NSValue *> *)textJustification {
+- (void)setTextJustification:(NSExpression *)textJustification {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TextJustifyType, NSValue *, mbgl::style::TextJustifyType, MGLTextJustification>().toDataDrivenPropertyValue(textJustification);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TextJustifyType, NSValue *, mbgl::style::TextJustifyType, MGLTextJustification>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::style::TextJustifyType>>(textJustification);
     self.rawLayer->setTextJustify(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)textJustification {
+- (NSExpression *)textJustification {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextJustify();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::TextJustifyType, NSValue *, mbgl::style::TextJustifyType, MGLTextJustification>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextJustify());
+        propertyValue = self.rawLayer->getDefaultTextJustify();
     }
-    return MGLStyleValueTransformer<mbgl::style::TextJustifyType, NSValue *, mbgl::style::TextJustifyType, MGLTextJustification>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::TextJustifyType, NSValue *, mbgl::style::TextJustifyType, MGLTextJustification>().toExpression(propertyValue);
 }
 
-- (void)setTextJustify:(MGLStyleValue<NSValue *> *)textJustify {
+- (void)setTextJustify:(NSExpression *)textJustify {
 }
 
-- (MGLStyleValue<NSValue *> *)textJustify {
+- (NSExpression *)textJustify {
     return self.textJustification;
 }
 
-- (void)setTextLetterSpacing:(MGLStyleValue<NSNumber *> *)textLetterSpacing {
+- (void)setTextLetterSpacing:(NSExpression *)textLetterSpacing {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(textLetterSpacing);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(textLetterSpacing);
     self.rawLayer->setTextLetterSpacing(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)textLetterSpacing {
+- (NSExpression *)textLetterSpacing {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextLetterSpacing();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextLetterSpacing());
+        propertyValue = self.rawLayer->getDefaultTextLetterSpacing();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setTextLineHeight:(MGLStyleValue<NSNumber *> *)textLineHeight {
+- (void)setTextLineHeight:(NSExpression *)textLineHeight {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(textLineHeight);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(textLineHeight);
     self.rawLayer->setTextLineHeight(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)textLineHeight {
+- (NSExpression *)textLineHeight {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextLineHeight();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultTextLineHeight());
+        propertyValue = self.rawLayer->getDefaultTextLineHeight();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setTextOffset:(MGLStyleValue<NSValue *> *)textOffset {
+- (void)setTextOffset:(NSExpression *)textOffset {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toDataDrivenPropertyValue(textOffset);
+    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<std::array<float, 2>>>(textOffset);
     self.rawLayer->setTextOffset(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)textOffset {
+- (NSExpression *)textOffset {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextOffset();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextOffset());
+        propertyValue = self.rawLayer->getDefaultTextOffset();
     }
-    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toExpression(propertyValue);
 }
 
-- (void)setTextOptional:(MGLStyleValue<NSNumber *> *)textOptional {
+- (void)setTextOptional:(NSExpression *)textOptional {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue(textOptional);
+    auto mbglValue = MGLStyleValueTransformer<bool, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<bool>>(textOptional);
     self.rawLayer->setTextOptional(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)isTextOptional {
+- (NSExpression *)isTextOptional {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextOptional();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(self.rawLayer->getDefaultTextOptional());
+        propertyValue = self.rawLayer->getDefaultTextOptional();
     }
-    return MGLStyleValueTransformer<bool, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<bool, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setTextPadding:(MGLStyleValue<NSNumber *> *)textPadding {
+- (void)setTextPadding:(NSExpression *)textPadding {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toInterpolatablePropertyValue(textPadding);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::PropertyValue<float>>(textPadding);
     self.rawLayer->setTextPadding(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)textPadding {
+- (NSExpression *)textPadding {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextPadding();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(self.rawLayer->getDefaultTextPadding());
+        propertyValue = self.rawLayer->getDefaultTextPadding();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setTextPitchAlignment:(MGLStyleValue<NSValue *> *)textPitchAlignment {
+- (void)setTextPitchAlignment:(NSExpression *)textPitchAlignment {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLTextPitchAlignment>().toEnumPropertyValue(textPitchAlignment);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLTextPitchAlignment>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::AlignmentType>>(textPitchAlignment);
     self.rawLayer->setTextPitchAlignment(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)textPitchAlignment {
+- (NSExpression *)textPitchAlignment {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextPitchAlignment();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLTextPitchAlignment>().toEnumStyleValue(self.rawLayer->getDefaultTextPitchAlignment());
+        propertyValue = self.rawLayer->getDefaultTextPitchAlignment();
     }
-    return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLTextPitchAlignment>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLTextPitchAlignment>().toExpression(propertyValue);
 }
 
-- (void)setTextRotation:(MGLStyleValue<NSNumber *> *)textRotation {
+- (void)setTextRotation:(NSExpression *)textRotation {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(textRotation);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(textRotation);
     self.rawLayer->setTextRotate(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)textRotation {
+- (NSExpression *)textRotation {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextRotate();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextRotate());
+        propertyValue = self.rawLayer->getDefaultTextRotate();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
-- (void)setTextRotate:(MGLStyleValue<NSNumber *> *)textRotate {
+- (void)setTextRotate:(NSExpression *)textRotate {
 }
 
-- (MGLStyleValue<NSNumber *> *)textRotate {
+- (NSExpression *)textRotate {
     return self.textRotation;
 }
 
-- (void)setTextRotationAlignment:(MGLStyleValue<NSValue *> *)textRotationAlignment {
+- (void)setTextRotationAlignment:(NSExpression *)textRotationAlignment {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLTextRotationAlignment>().toEnumPropertyValue(textRotationAlignment);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLTextRotationAlignment>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::AlignmentType>>(textRotationAlignment);
     self.rawLayer->setTextRotationAlignment(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)textRotationAlignment {
+- (NSExpression *)textRotationAlignment {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextRotationAlignment();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLTextRotationAlignment>().toEnumStyleValue(self.rawLayer->getDefaultTextRotationAlignment());
+        propertyValue = self.rawLayer->getDefaultTextRotationAlignment();
     }
-    return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLTextRotationAlignment>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::AlignmentType, NSValue *, mbgl::style::AlignmentType, MGLTextRotationAlignment>().toExpression(propertyValue);
 }
 
-- (void)setTextTransform:(MGLStyleValue<NSValue *> *)textTransform {
+- (void)setTextTransform:(NSExpression *)textTransform {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TextTransformType, NSValue *, mbgl::style::TextTransformType, MGLTextTransform>().toDataDrivenPropertyValue(textTransform);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TextTransformType, NSValue *, mbgl::style::TextTransformType, MGLTextTransform>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::style::TextTransformType>>(textTransform);
     self.rawLayer->setTextTransform(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)textTransform {
+- (NSExpression *)textTransform {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextTransform();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::TextTransformType, NSValue *, mbgl::style::TextTransformType, MGLTextTransform>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextTransform());
+        propertyValue = self.rawLayer->getDefaultTextTransform();
     }
-    return MGLStyleValueTransformer<mbgl::style::TextTransformType, NSValue *, mbgl::style::TextTransformType, MGLTextTransform>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::TextTransformType, NSValue *, mbgl::style::TextTransformType, MGLTextTransform>().toExpression(propertyValue);
 }
 
 #pragma mark - Accessing the Paint Attributes
 
-- (void)setIconColor:(MGLStyleValue<MGLColor *> *)iconColor {
+- (void)setIconColor:(NSExpression *)iconColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenPropertyValue(iconColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::Color>>(iconColor);
     self.rawLayer->setIconColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)iconColor {
+- (NSExpression *)iconColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(self.rawLayer->getDefaultIconColor());
+        propertyValue = self.rawLayer->getDefaultIconColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setIconColorTransition:(MGLTransition )transition {
@@ -922,21 +922,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setIconHaloBlur:(MGLStyleValue<NSNumber *> *)iconHaloBlur {
+- (void)setIconHaloBlur:(NSExpression *)iconHaloBlur {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(iconHaloBlur);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(iconHaloBlur);
     self.rawLayer->setIconHaloBlur(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)iconHaloBlur {
+- (NSExpression *)iconHaloBlur {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconHaloBlur();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultIconHaloBlur());
+        propertyValue = self.rawLayer->getDefaultIconHaloBlur();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setIconHaloBlurTransition:(MGLTransition )transition {
@@ -957,21 +957,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setIconHaloColor:(MGLStyleValue<MGLColor *> *)iconHaloColor {
+- (void)setIconHaloColor:(NSExpression *)iconHaloColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenPropertyValue(iconHaloColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::Color>>(iconHaloColor);
     self.rawLayer->setIconHaloColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)iconHaloColor {
+- (NSExpression *)iconHaloColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconHaloColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(self.rawLayer->getDefaultIconHaloColor());
+        propertyValue = self.rawLayer->getDefaultIconHaloColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setIconHaloColorTransition:(MGLTransition )transition {
@@ -992,21 +992,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setIconHaloWidth:(MGLStyleValue<NSNumber *> *)iconHaloWidth {
+- (void)setIconHaloWidth:(NSExpression *)iconHaloWidth {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(iconHaloWidth);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(iconHaloWidth);
     self.rawLayer->setIconHaloWidth(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)iconHaloWidth {
+- (NSExpression *)iconHaloWidth {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconHaloWidth();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultIconHaloWidth());
+        propertyValue = self.rawLayer->getDefaultIconHaloWidth();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setIconHaloWidthTransition:(MGLTransition )transition {
@@ -1027,21 +1027,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setIconOpacity:(MGLStyleValue<NSNumber *> *)iconOpacity {
+- (void)setIconOpacity:(NSExpression *)iconOpacity {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(iconOpacity);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(iconOpacity);
     self.rawLayer->setIconOpacity(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)iconOpacity {
+- (NSExpression *)iconOpacity {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconOpacity();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultIconOpacity());
+        propertyValue = self.rawLayer->getDefaultIconOpacity();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setIconOpacityTransition:(MGLTransition )transition {
@@ -1062,21 +1062,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setIconTranslation:(MGLStyleValue<NSValue *> *)iconTranslation {
+- (void)setIconTranslation:(NSExpression *)iconTranslation {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toInterpolatablePropertyValue(iconTranslation);
+    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toPropertyValue<mbgl::style::PropertyValue<std::array<float, 2>>>(iconTranslation);
     self.rawLayer->setIconTranslate(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)iconTranslation {
+- (NSExpression *)iconTranslation {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconTranslate();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toStyleValue(self.rawLayer->getDefaultIconTranslate());
+        propertyValue = self.rawLayer->getDefaultIconTranslate();
     }
-    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toExpression(propertyValue);
 }
 
 - (void)setIconTranslationTransition:(MGLTransition )transition {
@@ -1097,52 +1097,52 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setIconTranslate:(MGLStyleValue<NSValue *> *)iconTranslate {
+- (void)setIconTranslate:(NSExpression *)iconTranslate {
 }
 
-- (MGLStyleValue<NSValue *> *)iconTranslate {
+- (NSExpression *)iconTranslate {
     return self.iconTranslation;
 }
 
-- (void)setIconTranslationAnchor:(MGLStyleValue<NSValue *> *)iconTranslationAnchor {
+- (void)setIconTranslationAnchor:(NSExpression *)iconTranslationAnchor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLIconTranslationAnchor>().toEnumPropertyValue(iconTranslationAnchor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLIconTranslationAnchor>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::TranslateAnchorType>>(iconTranslationAnchor);
     self.rawLayer->setIconTranslateAnchor(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)iconTranslationAnchor {
+- (NSExpression *)iconTranslationAnchor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getIconTranslateAnchor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLIconTranslationAnchor>().toEnumStyleValue(self.rawLayer->getDefaultIconTranslateAnchor());
+        propertyValue = self.rawLayer->getDefaultIconTranslateAnchor();
     }
-    return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLIconTranslationAnchor>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLIconTranslationAnchor>().toExpression(propertyValue);
 }
 
-- (void)setIconTranslateAnchor:(MGLStyleValue<NSValue *> *)iconTranslateAnchor {
+- (void)setIconTranslateAnchor:(NSExpression *)iconTranslateAnchor {
 }
 
-- (MGLStyleValue<NSValue *> *)iconTranslateAnchor {
+- (NSExpression *)iconTranslateAnchor {
     return self.iconTranslationAnchor;
 }
 
-- (void)setTextColor:(MGLStyleValue<MGLColor *> *)textColor {
+- (void)setTextColor:(NSExpression *)textColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenPropertyValue(textColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::Color>>(textColor);
     self.rawLayer->setTextColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)textColor {
+- (NSExpression *)textColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextColor());
+        propertyValue = self.rawLayer->getDefaultTextColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setTextColorTransition:(MGLTransition )transition {
@@ -1163,21 +1163,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setTextHaloBlur:(MGLStyleValue<NSNumber *> *)textHaloBlur {
+- (void)setTextHaloBlur:(NSExpression *)textHaloBlur {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(textHaloBlur);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(textHaloBlur);
     self.rawLayer->setTextHaloBlur(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)textHaloBlur {
+- (NSExpression *)textHaloBlur {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextHaloBlur();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextHaloBlur());
+        propertyValue = self.rawLayer->getDefaultTextHaloBlur();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setTextHaloBlurTransition:(MGLTransition )transition {
@@ -1198,21 +1198,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setTextHaloColor:(MGLStyleValue<MGLColor *> *)textHaloColor {
+- (void)setTextHaloColor:(NSExpression *)textHaloColor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenPropertyValue(textHaloColor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<mbgl::Color>>(textHaloColor);
     self.rawLayer->setTextHaloColor(mbglValue);
 }
 
-- (MGLStyleValue<MGLColor *> *)textHaloColor {
+- (NSExpression *)textHaloColor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextHaloColor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextHaloColor());
+        propertyValue = self.rawLayer->getDefaultTextHaloColor();
     }
-    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::Color, MGLColor *>().toExpression(propertyValue);
 }
 
 - (void)setTextHaloColorTransition:(MGLTransition )transition {
@@ -1233,21 +1233,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setTextHaloWidth:(MGLStyleValue<NSNumber *> *)textHaloWidth {
+- (void)setTextHaloWidth:(NSExpression *)textHaloWidth {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(textHaloWidth);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(textHaloWidth);
     self.rawLayer->setTextHaloWidth(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)textHaloWidth {
+- (NSExpression *)textHaloWidth {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextHaloWidth();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextHaloWidth());
+        propertyValue = self.rawLayer->getDefaultTextHaloWidth();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setTextHaloWidthTransition:(MGLTransition )transition {
@@ -1268,21 +1268,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setTextOpacity:(MGLStyleValue<NSNumber *> *)textOpacity {
+- (void)setTextOpacity:(NSExpression *)textOpacity {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenPropertyValue(textOpacity);
+    auto mbglValue = MGLStyleValueTransformer<float, NSNumber *>().toPropertyValue<mbgl::style::DataDrivenPropertyValue<float>>(textOpacity);
     self.rawLayer->setTextOpacity(mbglValue);
 }
 
-- (MGLStyleValue<NSNumber *> *)textOpacity {
+- (NSExpression *)textOpacity {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextOpacity();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(self.rawLayer->getDefaultTextOpacity());
+        propertyValue = self.rawLayer->getDefaultTextOpacity();
     }
-    return MGLStyleValueTransformer<float, NSNumber *>().toDataDrivenStyleValue(propertyValue);
+    return MGLStyleValueTransformer<float, NSNumber *>().toExpression(propertyValue);
 }
 
 - (void)setTextOpacityTransition:(MGLTransition )transition {
@@ -1303,21 +1303,21 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setTextTranslation:(MGLStyleValue<NSValue *> *)textTranslation {
+- (void)setTextTranslation:(NSExpression *)textTranslation {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toInterpolatablePropertyValue(textTranslation);
+    auto mbglValue = MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toPropertyValue<mbgl::style::PropertyValue<std::array<float, 2>>>(textTranslation);
     self.rawLayer->setTextTranslate(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)textTranslation {
+- (NSExpression *)textTranslation {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextTranslate();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toStyleValue(self.rawLayer->getDefaultTextTranslate());
+        propertyValue = self.rawLayer->getDefaultTextTranslate();
     }
-    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toStyleValue(propertyValue);
+    return MGLStyleValueTransformer<std::array<float, 2>, NSValue *>().toExpression(propertyValue);
 }
 
 - (void)setTextTranslationTransition:(MGLTransition )transition {
@@ -1338,34 +1338,34 @@ namespace mbgl {
     return transition;
 }
 
-- (void)setTextTranslate:(MGLStyleValue<NSValue *> *)textTranslate {
+- (void)setTextTranslate:(NSExpression *)textTranslate {
 }
 
-- (MGLStyleValue<NSValue *> *)textTranslate {
+- (NSExpression *)textTranslate {
     return self.textTranslation;
 }
 
-- (void)setTextTranslationAnchor:(MGLStyleValue<NSValue *> *)textTranslationAnchor {
+- (void)setTextTranslationAnchor:(NSExpression *)textTranslationAnchor {
     MGLAssertStyleLayerIsValid();
 
-    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLTextTranslationAnchor>().toEnumPropertyValue(textTranslationAnchor);
+    auto mbglValue = MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLTextTranslationAnchor>().toPropertyValue<mbgl::style::PropertyValue<mbgl::style::TranslateAnchorType>>(textTranslationAnchor);
     self.rawLayer->setTextTranslateAnchor(mbglValue);
 }
 
-- (MGLStyleValue<NSValue *> *)textTranslationAnchor {
+- (NSExpression *)textTranslationAnchor {
     MGLAssertStyleLayerIsValid();
 
     auto propertyValue = self.rawLayer->getTextTranslateAnchor();
     if (propertyValue.isUndefined()) {
-        return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLTextTranslationAnchor>().toEnumStyleValue(self.rawLayer->getDefaultTextTranslateAnchor());
+        propertyValue = self.rawLayer->getDefaultTextTranslateAnchor();
     }
-    return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLTextTranslationAnchor>().toEnumStyleValue(propertyValue);
+    return MGLStyleValueTransformer<mbgl::style::TranslateAnchorType, NSValue *, mbgl::style::TranslateAnchorType, MGLTextTranslationAnchor>().toExpression(propertyValue);
 }
 
-- (void)setTextTranslateAnchor:(MGLStyleValue<NSValue *> *)textTranslateAnchor {
+- (void)setTextTranslateAnchor:(NSExpression *)textTranslateAnchor {
 }
 
-- (MGLStyleValue<NSValue *> *)textTranslateAnchor {
+- (NSExpression *)textTranslateAnchor {
     return self.textTranslationAnchor;
 }
 
diff --git a/platform/darwin/src/MGLVectorStyleLayer.h b/platform/darwin/src/MGLVectorStyleLayer.h
index 6603570e25..7780a34c7f 100644
--- a/platform/darwin/src/MGLVectorStyleLayer.h
+++ b/platform/darwin/src/MGLVectorStyleLayer.h
@@ -34,108 +34,9 @@ MGL_EXPORT
  comes from the style, its predicate corresponds to the
  <a href="https://www.mapbox.com/mapbox-gl-style-spec/#layer-filter">`filter`</a>
  property in the style JSON.
-
- The following comparison operators are supported.
-
- <ul>
- <li><code>NSEqualToPredicateOperatorType</code> (<code>=</code>, <code>==</code>)</li>
- <li><code>NSGreaterThanOrEqualToPredicateOperatorType</code> (<code>>=</code>, <code>=></code>)</li>
- <li><code>NSLessThanOrEqualToPredicateOperatorType</code> (<code><=</code>, <code>=<</code>)</li>
- <li><code>NSGreaterThanPredicateOperatorType</code> (<code>></code>)</li>
- <li><code>NSLessThanPredicateOperatorType</code> (<code><</code>)</li>
- <li><code>NSNotEqualToPredicateOperatorType</code> (<code>!=</code>, <code><></code>)</li>
- <li><code>NSBetweenPredicateOperatorType</code> (<code>BETWEEN</code>)</li>
- </ul>
-
- The following compound operators are supported:
-
- <ul>
- <li><code>NSAndPredicateType</code> (<code>AND</code>, <code>&&</code>)</li>
- <li><code>NSOrPredicateType</code> (<code>OR</code>, <code>||</code>)</li>
- <li><code>NSNotPredicateType</code> (<code>NOT</code>, <code>!</code>)</li>
- </ul>
-
- The following aggregate operators are supported:
-
- <ul>
- <li><code>NSInPredicateOperatorType</code> (<code>IN</code>)</li>
- <li><code>NSContainsPredicateOperatorType</code> (<code>CONTAINS</code>)</li>
- </ul>
-
- To test whether a feature has or lacks a specific attribute, compare the
- attribute to `NULL` or `NIL`. Predicates created using the
- `+[NSPredicate predicateWithValue:]` method are also supported. String
- operators and custom operators are not supported.
-
- For details about the predicate format string syntax, consult the “Predicate
- Format String Syntax” chapter of the
- “<a href="https://developer.apple.com/library/content/documentation/Cocoa/Conceptual/Predicates/">Predicate Programming Guide</a>”
- in Apple developer documentation.
-
- The predicate's left-hand expression must be a string that identifies a feature
- attribute or, alternatively, one of the following special attributes:
-
- <table>
- <thead>
- <tr><th>Attribute</th><th>Meaning</th></tr>
- </thead>
- <tbody>
- <tr>
-    <td><code>$id</code></td>
-    <td>
-        A value that uniquely identifies the feature in the containing source.
-        For details on the types of values that may be associated with this key,
-        consult the documentation for the <code>MGLFeature</code> protocol’s
-        <code>identifier</code> property.
-    </td>
- </tr>
- <tr>
-    <td><code>$type</code></td>
-    <td>
-        The type of geometry represented by the feature. A feature’s type is
-        guaranteed to be one of the following strings:
-        <ul>
-            <li>
-                <code>Point</code> for point features, corresponding to the
-                <code>MGLPointAnnotation</code> class
-            </li>
-            <li>
-                <code>LineString</code> for polyline features, corresponding to
-                the <code>MGLPolyline</code> class
-            </li>
-            <li>
-                <code>Polygon</code> for polygon features, corresponding to the
-                <code>MGLPolygon</code> class
-            </li>
-        </ul>
-    </td>
- </tr>
- <tr>
-    <td><code>point_count</code></td>
-    <td>The number of point features in a given cluster.</td>
- </tr>
- </tbody>
- </table>
-
- The predicate’s right-hand expression must be an `NSString` (to match strings)
- or `NSNumber` (to match numbers, including Boolean values) or an array of
- `NSString`s or `NSNumber`s, depending on the operator and the type of values
- expected for the attribute being tested. For floating-point values, use
- `-[NSNumber numberWithDouble:]` instead of `-[NSNumber numberWithFloat:]`
- to avoid precision issues.
-
- Automatic type casting is not performed. Therefore, a feature only matches this
- predicate if its value for the attribute in question is of the same type as the
- value specified in the predicate. Also, operator modifiers such as `c` (for
- case insensitivity), `d` (for diacritic insensitivity), and `l` (for locale
- sensitivity) are unsupported for comparison and aggregate operators that are
- used in the predicate.
-
- It is possible to create expressions that contain special characters in the
- predicate format syntax. This includes the `$` in the `$id` and `$type` special
- style attributes and also `hyphen-minus` and `tag:subtag`. However, you must use
- `%K` in the format string to represent these variables:
- `@"%K == 'LineString'", @"$type"`.
+ 
+ See the “<a href="../predicates-and-expressions.html">Predicates and Expressions</a>”
+ guide for details about the predicate syntax supported by this class.
 
  ### Example
 
diff --git a/platform/darwin/src/NSArray+MGLAdditions.mm b/platform/darwin/src/NSArray+MGLAdditions.mm
index 3cab7ff427..195e96b09d 100644
--- a/platform/darwin/src/NSArray+MGLAdditions.mm
+++ b/platform/darwin/src/NSArray+MGLAdditions.mm
@@ -1,7 +1,7 @@
 #import "NSArray+MGLAdditions.h"
 
 #import "NSDictionary+MGLAdditions.h"
-#import "NSExpression+MGLAdditions.mm"
+#import "NSExpression+MGLPrivateAdditions.h"
 
 @implementation NSArray (MGLAdditions)
 
diff --git a/platform/darwin/src/NSComparisonPredicate+MGLAdditions.mm b/platform/darwin/src/NSComparisonPredicate+MGLAdditions.mm
index ac2d598d05..5b54d66aeb 100644
--- a/platform/darwin/src/NSComparisonPredicate+MGLAdditions.mm
+++ b/platform/darwin/src/NSComparisonPredicate+MGLAdditions.mm
@@ -1,7 +1,7 @@
 #import "NSComparisonPredicate+MGLAdditions.h"
 
 #import "NSPredicate+MGLAdditions.h"
-#import "NSExpression+MGLAdditions.h"
+#import "NSExpression+MGLPrivateAdditions.h"
 
 @implementation NSComparisonPredicate (MGLAdditions)
 
@@ -294,3 +294,45 @@
 }
 
 @end
+
+@implementation NSComparisonPredicate (MGLExpressionAdditions)
+
+- (id)mgl_jsonExpressionObject {
+    NSString *op;
+    switch (self.predicateOperatorType) {
+        case NSLessThanPredicateOperatorType:
+            op = @"<";
+            break;
+        case NSLessThanOrEqualToPredicateOperatorType:
+            op = @"<=";
+            break;
+        case NSGreaterThanPredicateOperatorType:
+            op = @">";
+            break;
+        case NSGreaterThanOrEqualToPredicateOperatorType:
+            op = @">=";
+            break;
+        case NSEqualToPredicateOperatorType:
+            op = @"==";
+            break;
+        case NSNotEqualToPredicateOperatorType:
+            op = @"!=";
+            break;
+        case NSMatchesPredicateOperatorType:
+        case NSLikePredicateOperatorType:
+        case NSBeginsWithPredicateOperatorType:
+        case NSEndsWithPredicateOperatorType:
+        case NSInPredicateOperatorType:
+        case NSCustomSelectorPredicateOperatorType:
+        case NSContainsPredicateOperatorType:
+        case NSBetweenPredicateOperatorType:
+            [NSException raise:NSInvalidArgumentException
+                        format:@"NSPredicateOperatorType:%lu is not supported.", (unsigned long)self.predicateOperatorType];
+    }
+    if (op) {
+        return @[op, self.leftExpression.mgl_jsonExpressionObject, self.rightExpression.mgl_jsonExpressionObject];
+    }
+    return nil;
+}
+
+@end
diff --git a/platform/darwin/src/NSCompoundPredicate+MGLAdditions.mm b/platform/darwin/src/NSCompoundPredicate+MGLAdditions.mm
index 0039b5af82..19568b8033 100644
--- a/platform/darwin/src/NSCompoundPredicate+MGLAdditions.mm
+++ b/platform/darwin/src/NSCompoundPredicate+MGLAdditions.mm
@@ -1,7 +1,7 @@
 #import "NSCompoundPredicate+MGLAdditions.h"
 
 #import "NSPredicate+MGLAdditions.h"
-#import "NSExpression+MGLAdditions.h"
+#import "NSExpression+MGLPrivateAdditions.h"
 
 @implementation NSCompoundPredicate (MGLAdditions)
 
@@ -71,3 +71,31 @@
 }
 
 @end
+
+@implementation NSCompoundPredicate (MGLExpressionAdditions)
+
+- (id)mgl_jsonExpressionObject {
+    switch (self.compoundPredicateType) {
+        case NSNotPredicateType: {
+            NSAssert(self.subpredicates.count <= 1, @"NOT predicate cannot have multiple subpredicates.");
+            NSPredicate *subpredicate = self.subpredicates.firstObject;
+            return @[@"!", subpredicate.mgl_jsonExpressionObject];
+        }
+            
+        case NSAndPredicateType: {
+            NSArray *subarrays = [self.subpredicates valueForKeyPath:@"mgl_jsonExpressionObject"];
+            return [@[@"all"] arrayByAddingObjectsFromArray:subarrays];
+        }
+            
+        case NSOrPredicateType: {
+            NSArray *subarrays = [self.subpredicates valueForKeyPath:@"mgl_jsonExpressionObject"];
+            return [@[@"any"] arrayByAddingObjectsFromArray:subarrays];
+        }
+    }
+    
+    [NSException raise:@"Compound predicate type not handled"
+                format:@""];
+    return nil;
+}
+
+@end
diff --git a/platform/darwin/src/NSDictionary+MGLAdditions.mm b/platform/darwin/src/NSDictionary+MGLAdditions.mm
index aad7fd8810..4bc7ddb3cf 100644
--- a/platform/darwin/src/NSDictionary+MGLAdditions.mm
+++ b/platform/darwin/src/NSDictionary+MGLAdditions.mm
@@ -1,6 +1,6 @@
 #import "NSDictionary+MGLAdditions.h"
 
-#import "NSExpression+MGLAdditions.mm"
+#import "NSExpression+MGLPrivateAdditions.h"
 #import "NSArray+MGLAdditions.h"
 
 @implementation NSDictionary (MGLAdditions)
diff --git a/platform/darwin/src/NSExpression+MGLAdditions.h b/platform/darwin/src/NSExpression+MGLAdditions.h
index 491ed5a536..b4d36bc1b1 100644
--- a/platform/darwin/src/NSExpression+MGLAdditions.h
+++ b/platform/darwin/src/NSExpression+MGLAdditions.h
@@ -1,17 +1,46 @@
 #import <Foundation/Foundation.h>
+#if TARGET_OS_IPHONE
+    #import <UIKit/UIKit.h>
+#else
+    #import <Cocoa/Cocoa.h>
+#endif
 
-#include <mbgl/style/filter.hpp>
+#import "MGLTypes.h"
 
 NS_ASSUME_NONNULL_BEGIN
 
 @interface NSExpression (MGLAdditions)
 
-@property (nonatomic, readonly) mbgl::Value mgl_constantMBGLValue;
-@property (nonatomic, readonly) std::vector<mbgl::Value> mgl_aggregateMBGLValue;
-@property (nonatomic, readonly) mbgl::FeatureType mgl_featureType;
-@property (nonatomic, readonly) std::vector<mbgl::FeatureType> mgl_aggregateFeatureType;
-@property (nonatomic, readonly) mbgl::FeatureIdentifier mgl_featureIdentifier;
-@property (nonatomic, readonly) std::vector<mbgl::FeatureIdentifier> mgl_aggregateFeatureIdentifier;
+/**
+ Returns an expression equivalent to the given Foundation object deserialized
+ from JSON data.
+ 
+ The Foundation object is interpreted according to the
+ [Mapbox Style Specification](https://www.mapbox.com/mapbox-gl-js/style-spec/#expressions).
+ See the “[Predicates and Expressions](../predicates-and-expressions.html)”
+ guide for a correspondence of operators and types between the style
+ specification and the `NSExpression` representation used by this SDK.
+ 
+ @param object A Foundation object deserialized from JSON data, for example
+    using `NSJSONSerialization`.
+ @return An initialized expression equivalent to `object`, suitable for use as
+    the value of a style layer attribute.
+ */
++ (instancetype)mgl_expressionWithJSONObject:(id)object;
+
+/**
+ An equivalent Foundation object that can be serialized as JSON.
+ 
+ The Foundation object conforms to the
+ [Mapbox Style Specification](https://www.mapbox.com/mapbox-gl-js/style-spec/#expressions).
+ See the “[Predicates and Expressions](../predicates-and-expressions.html)”
+ guide for a correspondence of operators and types between the style
+ specification and the `NSExpression` representation used by this SDK.
+ 
+ You can use `NSJSONSerialization` to serialize the Foundation object as data to
+ write to a file.
+ */
+@property (nonatomic, readonly) id mgl_jsonExpressionObject;
 
 @end
 
diff --git a/platform/darwin/src/NSExpression+MGLAdditions.mm b/platform/darwin/src/NSExpression+MGLAdditions.mm
index a7759cda9d..5ad565c398 100644
--- a/platform/darwin/src/NSExpression+MGLAdditions.mm
+++ b/platform/darwin/src/NSExpression+MGLAdditions.mm
@@ -1,13 +1,19 @@
-#import "NSExpression+MGLAdditions.h"
+#import "NSExpression+MGLPrivateAdditions.h"
 
 #import "MGLTypes.h"
 #if TARGET_OS_IPHONE
     #import "UIColor+MGLAdditions.h"
+    #define MGLEdgeInsets UIEdgeInsets
 #else
     #import "NSColor+MGLAdditions.h"
+    #define MGLEdgeInsets NSEdgeInsets
 #endif
+#import "NSPredicate+MGLAdditions.h"
+#import "NSValue+MGLStyleAttributeAdditions.h"
 
-@implementation NSExpression (MGLAdditions)
+#import <mbgl/style/expression/expression.hpp>
+
+@implementation NSExpression (MGLPrivateAdditions)
 
 - (std::vector<mbgl::Value>)mgl_aggregateMBGLValue {
     if ([self.constantValue isKindOfClass:[NSArray class]] || [self.constantValue isKindOfClass:[NSSet class]]) {
@@ -154,3 +160,578 @@
 }
 
 @end
+
+@implementation NSObject (MGLExpressionAdditions)
+
+- (NSNumber *)mgl_number {
+    return nil;
+}
+
+- (NSNumber *)mgl_numberWithFallbackValues:(id)fallbackValue, ... {
+    if (self.mgl_number) {
+        return self.mgl_number;
+    }
+    
+    va_list fallbackValues;
+    va_start(fallbackValues, fallbackValue);
+    for (id value = fallbackValue; value; value = va_arg(fallbackValues, id)) {
+        if ([value mgl_number]) {
+            return [value mgl_number];
+        }
+    }
+    
+    return nil;
+}
+
+@end
+
+@implementation NSNull (MGLExpressionAdditions)
+
+- (id)mgl_jsonExpressionObject {
+    return self;
+}
+
+@end
+
+@implementation NSString (MGLExpressionAdditions)
+
+- (id)mgl_jsonExpressionObject {
+    return self;
+}
+
+- (NSNumber *)mgl_number {
+    if (self.doubleValue || ![[NSDecimalNumber decimalNumberWithString:self] isEqual:[NSDecimalNumber notANumber]]) {
+        return @(self.doubleValue);
+    }
+    
+    return nil;
+}
+
+@end
+
+@implementation NSNumber (MGLExpressionAdditions)
+
+- (id)mgl_interpolateWithCurveType:(NSString *)curveType
+                        parameters:(NSArray *)parameters
+                             stops:(NSDictionary<NSNumber *, id> *)stops {
+    [NSException raise:NSInvalidArgumentException
+                format:@"Interpolation expressions lack underlying Objective-C implementations."];
+    return nil;
+}
+
+- (id)mgl_stepWithMinimum:(id)minimum stops:(NSDictionary<NSNumber *, id> *)stops {
+    [NSException raise:NSInvalidArgumentException
+                format:@"Interpolation expressions lack underlying Objective-C implementations."];
+    return nil;
+}
+
+- (NSNumber *)mgl_number {
+    return self;
+}
+
+- (id)mgl_jsonExpressionObject {
+    if ([self isEqualToNumber:@(M_E)]) {
+        return @[@"e"];
+    } else if ([self isEqualToNumber:@(M_PI)]) {
+        return @[@"pi"];
+    }
+    return self;
+}
+
+@end
+
+@implementation MGLColor (MGLExpressionAdditions)
+
+- (id)mgl_jsonExpressionObject {
+    auto color = [self mgl_color];
+    if (color.a == 1) {
+        return @[@"rgb", @(color.r * 255), @(color.g * 255), @(color.b * 255)];
+    }
+    return @[@"rgba", @(color.r * 255), @(color.g * 255), @(color.b * 255), @(color.a)];
+}
+
+@end
+
+@implementation NSArray (MGLExpressionAdditions)
+
+- (id)mgl_jsonExpressionObject {
+    return [self valueForKeyPath:@"mgl_jsonExpressionObject"];
+}
+
+@end
+
+@implementation NSDictionary (MGLExpressionAdditions)
+
+- (id)mgl_jsonExpressionObject {
+    NSMutableDictionary *expressionObject = [NSMutableDictionary dictionaryWithCapacity:self.count];
+    [self enumerateKeysAndObjectsUsingBlock:^(id _Nonnull key, id _Nonnull obj, BOOL * _Nonnull stop) {
+        expressionObject[[key mgl_jsonExpressionObject]] = [obj mgl_jsonExpressionObject];
+    }];
+    
+    return expressionObject;
+}
+
+@end
+
+@implementation NSExpression (MGLExpressionAdditions)
+
+- (NSExpression *)mgl_expressionWithContext:(NSDictionary<NSString *, NSExpression *> *)context {
+    [NSException raise:NSInternalInconsistencyException
+                format:@"Assignment expressions lack underlying Objective-C implementations."];
+    return self;
+}
+
+@end
+
+@implementation NSExpression (MGLAdditions)
+
+static NSDictionary<NSString *, NSString *> *MGLFunctionNamesByExpressionOperator;
+static NSDictionary<NSString *, NSString *> *MGLExpressionOperatorsByFunctionNames;
+
+NSArray *MGLSubexpressionsWithJSONObjects(NSArray *objects) {
+    NSMutableArray *subexpressions = [NSMutableArray arrayWithCapacity:objects.count];
+    for (id object in objects) {
+        NSExpression *expression = [NSExpression mgl_expressionWithJSONObject:object];
+        [subexpressions addObject:expression];
+    }
+    return subexpressions;
+}
+
++ (instancetype)mgl_expressionWithJSONObject:(id)object {
+    static dispatch_once_t onceToken;
+    dispatch_once(&onceToken, ^{
+        MGLFunctionNamesByExpressionOperator = @{
+            @"+": @"add:to:",
+            @"-": @"from:subtract:",
+            @"*": @"multiply:by:",
+            @"/": @"divide:by:",
+            @"%": @"modulus:by:",
+            @"sqrt": @"sqrt:",
+            @"log10": @"log:",
+            @"ln": @"ln:",
+            @"^": @"raise:toPower:",
+            @"upcase": @"uppercase:",
+            @"downcase": @"lowercase:",
+        };
+    });
+    
+    if (!object || object == [NSNull null]) {
+        return [NSExpression expressionForConstantValue:nil];
+    }
+    
+    if ([object isKindOfClass:[NSString class]] ||
+        [object isKindOfClass:[NSNumber class]] ||
+        [object isKindOfClass:[NSValue class]] ||
+        [object isKindOfClass:[MGLColor class]]) {
+        return [NSExpression expressionForConstantValue:object];
+    }
+    
+    if ([object isKindOfClass:[NSDictionary class]]) {
+        NSMutableDictionary *dictionary = [NSMutableDictionary dictionaryWithCapacity:[object count]];
+        [object enumerateKeysAndObjectsUsingBlock:^(id _Nonnull key, id _Nonnull obj, BOOL * _Nonnull stop) {
+            dictionary[key] = [NSExpression mgl_expressionWithJSONObject:obj];
+        }];
+        return [NSExpression expressionForConstantValue:dictionary];
+    }
+    
+    if ([object isKindOfClass:[NSArray class]]) {
+        NSArray *array = (NSArray *)object;
+        NSString *op = array.firstObject;
+        
+        NSArray *argumentObjects = [array subarrayWithRange:NSMakeRange(1, array.count - 1)];
+        
+        NSString *functionName = MGLFunctionNamesByExpressionOperator[op];
+        if (functionName) {
+            NSArray *subexpressions = MGLSubexpressionsWithJSONObjects(argumentObjects);
+            if ([op isEqualToString:@"+"] && argumentObjects.count > 2) {
+                NSExpression *subexpression = [NSExpression expressionForAggregate:subexpressions];
+                return [NSExpression expressionForFunction:@"sum:"
+                                                 arguments:@[subexpression]];
+            } else if ([op isEqualToString:@"^"] && [argumentObjects.firstObject isEqual:@[@"e"]]) {
+                functionName = @"exp:";
+                subexpressions = [subexpressions subarrayWithRange:NSMakeRange(1, subexpressions.count - 1)];
+            }
+            
+            return [NSExpression expressionForFunction:functionName
+                                             arguments:subexpressions];
+        } else if ([op isEqualToString:@"literal"]) {
+            if ([argumentObjects.firstObject isKindOfClass:[NSArray class]]) {
+                return [NSExpression expressionForAggregate:MGLSubexpressionsWithJSONObjects(argumentObjects.firstObject)];
+            }
+            return [NSExpression mgl_expressionWithJSONObject:argumentObjects.firstObject];
+        } else if ([op isEqualToString:@"to-boolean"]) {
+            NSExpression *operand = [NSExpression mgl_expressionWithJSONObject:argumentObjects.firstObject];
+            return [NSExpression expressionForFunction:operand selectorName:@"boolValue" arguments:@[]];
+        } else if ([op isEqualToString:@"to-number"]) {
+            NSExpression *operand = [NSExpression mgl_expressionWithJSONObject:argumentObjects.firstObject];
+            argumentObjects = [argumentObjects subarrayWithRange:NSMakeRange(1, argumentObjects.count - 1)];
+            NSArray *subexpressions = MGLSubexpressionsWithJSONObjects(argumentObjects);
+            return [NSExpression expressionForFunction:operand selectorName:@"mgl_numberWithFallbackValues:" arguments:subexpressions];
+        } else if ([op isEqualToString:@"to-string"]) {
+            NSExpression *operand = [NSExpression mgl_expressionWithJSONObject:argumentObjects.firstObject];
+            return [NSExpression expressionForFunction:operand selectorName:@"stringValue" arguments:@[]];
+        } else if ([op isEqualToString:@"get"]) {
+            if (argumentObjects.count == 2) {
+                NSExpression *operand = [NSExpression mgl_expressionWithJSONObject:argumentObjects.lastObject];
+                if ([argumentObjects.firstObject isKindOfClass:[NSString class]]) {
+                    return [NSExpression expressionWithFormat:@"%@.%K", operand, argumentObjects.firstObject];
+                }
+                NSExpression *key = [NSExpression mgl_expressionWithJSONObject:argumentObjects.firstObject];
+                return [NSExpression expressionWithFormat:@"%@.%@", operand, key];
+            }
+            return [NSExpression expressionForKeyPath:argumentObjects.firstObject];
+        } else if ([op isEqualToString:@"length"]) {
+            NSArray *subexpressions = MGLSubexpressionsWithJSONObjects(argumentObjects);
+            return [NSExpression expressionForFunction:@"count:" arguments:@[subexpressions.firstObject]];
+        } else if ([op isEqualToString:@"min"]) {
+            NSArray *subexpressions = MGLSubexpressionsWithJSONObjects(argumentObjects);
+            NSExpression *subexpression = [NSExpression expressionForAggregate:subexpressions];
+            return [NSExpression expressionForFunction:@"min:" arguments:@[subexpression]];
+        } else if ([op isEqualToString:@"max"]) {
+            NSArray *subexpressions = MGLSubexpressionsWithJSONObjects(argumentObjects);
+            NSExpression *subexpression = [NSExpression expressionForAggregate:subexpressions];
+            return [NSExpression expressionForFunction:@"max:" arguments:@[subexpression]];
+        } else if ([op isEqualToString:@"e"]) {
+            return [NSExpression expressionForConstantValue:@(M_E)];
+        } else if ([op isEqualToString:@"pi"]) {
+            return [NSExpression expressionForConstantValue:@(M_PI)];
+        } else if ([op isEqualToString:@"concat"]) {
+            NSArray *subexpressions = MGLSubexpressionsWithJSONObjects(argumentObjects);
+            NSExpression *operand = subexpressions.firstObject;
+            subexpressions = [subexpressions subarrayWithRange:NSMakeRange(1, subexpressions.count - 1)];
+            return [NSExpression expressionForFunction:operand selectorName:@"stringByAppendingString:" arguments:subexpressions];
+        } else if ([op isEqualToString:@"interpolate"]) {
+            NSArray *interpolationOptions = argumentObjects.firstObject;
+            NSString *curveType = interpolationOptions.firstObject;
+            NSExpression *curveTypeExpression = [NSExpression mgl_expressionWithJSONObject:curveType];
+            id curveParameters;
+            if ([curveType isEqual:@"exponential"]) {
+                curveParameters = interpolationOptions[1];
+            } else if ([curveType isEqualToString:@"cubic-bezier"]) {
+                curveParameters = @[@"literal", [interpolationOptions subarrayWithRange:NSMakeRange(1, 4)]];
+            }
+            NSExpression *curveParameterExpression = [NSExpression mgl_expressionWithJSONObject:curveParameters];
+            argumentObjects = [argumentObjects subarrayWithRange:NSMakeRange(1, argumentObjects.count - 1)];
+            NSExpression *operand = [NSExpression mgl_expressionWithJSONObject:argumentObjects.firstObject];
+            NSArray *stopExpressions = [argumentObjects subarrayWithRange:NSMakeRange(1, argumentObjects.count - 1)];
+            NSMutableDictionary *stops = [NSMutableDictionary dictionaryWithCapacity:stopExpressions.count / 2];
+            NSEnumerator *stopEnumerator = stopExpressions.objectEnumerator;
+            while (NSNumber *key = stopEnumerator.nextObject) {
+                NSExpression *valueExpression = stopEnumerator.nextObject;
+                stops[key] = [NSExpression mgl_expressionWithJSONObject:valueExpression];
+            }
+            NSExpression *stopExpression = [NSExpression expressionForConstantValue:stops];
+            return [NSExpression expressionForFunction:operand
+                                          selectorName:@"mgl_interpolateWithCurveType:parameters:stops:"
+                                             arguments:@[curveTypeExpression, curveParameterExpression, stopExpression]];
+        } else if ([op isEqualToString:@"step"]) {
+            NSExpression *operand = [NSExpression mgl_expressionWithJSONObject:argumentObjects[0]];
+            NSArray *stopExpressions = [argumentObjects subarrayWithRange:NSMakeRange(1, argumentObjects.count - 1)];
+            NSExpression *minimum;
+            if (stopExpressions.count % 2) {
+                minimum = [NSExpression mgl_expressionWithJSONObject:stopExpressions.firstObject];
+                stopExpressions = [stopExpressions subarrayWithRange:NSMakeRange(1, stopExpressions.count - 1)];
+            }
+            NSMutableDictionary *stops = [NSMutableDictionary dictionaryWithCapacity:stopExpressions.count / 2];
+            NSEnumerator *stopEnumerator = stopExpressions.objectEnumerator;
+            while (NSNumber *key = stopEnumerator.nextObject) {
+                NSExpression *valueExpression = stopEnumerator.nextObject;
+                if (minimum) {
+                    stops[key] = [NSExpression mgl_expressionWithJSONObject:valueExpression];
+                } else {
+                    minimum = [NSExpression mgl_expressionWithJSONObject:valueExpression];
+                }
+            }
+            NSExpression *stopExpression = [NSExpression expressionForConstantValue:stops];
+            return [NSExpression expressionForFunction:operand
+                                          selectorName:@"mgl_stepWithMinimum:stops:"
+                                             arguments:@[minimum, stopExpression]];
+        } else if ([op isEqualToString:@"zoom"]) {
+            return [NSExpression expressionForVariable:@"zoomLevel"];
+        } else if ([op isEqualToString:@"heatmap-density"]) {
+            return [NSExpression expressionForVariable:@"heatmapDensity"];
+        } else if ([op isEqualToString:@"let"]) {
+            NSExpression *operand = [NSExpression mgl_expressionWithJSONObject:argumentObjects.lastObject];
+            NSArray *bindingObjects = [argumentObjects subarrayWithRange:NSMakeRange(0, argumentObjects.count - 1)];
+            NSMutableDictionary *context = [NSMutableDictionary dictionaryWithCapacity:bindingObjects.count / 2];
+            NSEnumerator *bindingEnumerator = bindingObjects.objectEnumerator;
+            while (NSString *key = bindingEnumerator.nextObject) {
+                context[key] = [NSExpression mgl_expressionWithJSONObject:bindingEnumerator.nextObject];
+            }
+            return [NSExpression expressionForFunction:operand
+                                          selectorName:@"mgl_expressionWithContext:"
+                                             arguments:@[[NSExpression expressionForConstantValue:context]]];
+        } else if ([op isEqualToString:@"var"]) {
+            return [NSExpression expressionForVariable:argumentObjects.firstObject];
+        } else if ([op isEqualToString:@"case"]) {
+            NSPredicate *conditional = [NSPredicate mgl_predicateWithJSONObject:argumentObjects.firstObject];
+            NSExpression *trueExpression = [NSExpression mgl_expressionWithJSONObject:argumentObjects[1]];
+            NSExpression *falseExpression;
+            if (argumentObjects.count > 3) {
+                NSArray *falseObjects = [@[@"case"] arrayByAddingObjectsFromArray:
+                                         [argumentObjects subarrayWithRange:NSMakeRange(2, argumentObjects.count - 2)]];
+                falseExpression = [NSExpression mgl_expressionWithJSONObject:falseObjects];
+            } else {
+                falseExpression = [NSExpression mgl_expressionWithJSONObject:argumentObjects[2]];
+            }
+            return [NSExpression expressionForConditional:conditional trueExpression:trueExpression falseExpression:falseExpression];
+        } else {
+            [NSException raise:NSInvalidArgumentException
+                        format:@"Expression operator %@ not yet implemented.", op];
+        }
+    }
+    
+    [NSException raise:NSInvalidArgumentException
+                format:@"Unable to convert JSON object %@ to an NSExpression.", object];
+    
+    return nil;
+}
+
+- (id)mgl_jsonExpressionObject {
+    static dispatch_once_t onceToken;
+    dispatch_once(&onceToken, ^{
+        MGLExpressionOperatorsByFunctionNames = @{
+            @"add:to:": @"+",
+            @"from:subtract:": @"-",
+            @"multiply:by:": @"*",
+            @"divide:by:": @"/",
+            @"modulus:by:": @"%",
+            @"sqrt:": @"sqrt",
+            @"log:": @"log10",
+            @"ln:": @"ln",
+            @"raise:toPower:": @"^",
+            @"uppercase:": @"upcase",
+            @"lowercase:": @"downcase",
+        };
+    });
+    
+    switch (self.expressionType) {
+        case NSVariableExpressionType: {
+            if ([self.variable isEqualToString:@"heatmapDensity"]) {
+                return @[@"heatmap-density"];
+            }
+            if ([self.variable isEqualToString:@"zoomLevel"]) {
+                return @[@"zoom"];
+            }
+            return @[@"var", self.variable];
+        }
+        
+        case NSConstantValueExpressionType: {
+            id constantValue = self.constantValue;
+            if (!constantValue || constantValue == [NSNull null]) {
+                return [NSNull null];
+            }
+            if ([constantValue isEqual:@(M_E)]) {
+                return @[@"e"];
+            }
+            if ([constantValue isEqual:@(M_PI)]) {
+                return @[@"pi"];
+            }
+            if ([constantValue isKindOfClass:[NSArray class]] ||
+                [constantValue isKindOfClass:[NSDictionary class]]) {
+                NSArray *collection = [constantValue mgl_jsonExpressionObject];
+                return @[@"literal", collection];
+            }
+            if ([constantValue isKindOfClass:[MGLColor class]]) {
+                auto color = [constantValue mgl_color];
+                if (color.a == 1) {
+                    return @[@"rgb", @(color.r * 255), @(color.g * 255), @(color.b * 255)];
+                }
+                return @[@"rgba", @(color.r * 255), @(color.g * 255), @(color.b * 255), @(color.a)];
+            }
+            if ([constantValue isKindOfClass:[NSValue class]]) {
+                const auto boxedValue = (NSValue *)constantValue;
+                if (strcmp([boxedValue objCType], @encode(CGVector)) == 0) {
+                    // offset [x, y]
+                    std::array<float, 2> mglValue = boxedValue.mgl_offsetArrayValue;
+                    return @[@"literal", @[@(mglValue[0]), @(mglValue[1])]];
+                }
+                if (strcmp([boxedValue objCType], @encode(MGLEdgeInsets)) == 0) {
+                    // padding [x, y]
+                    std::array<float, 4> mglValue = boxedValue.mgl_paddingArrayValue;
+                    return @[@"literal", @[@(mglValue[0]), @(mglValue[1]), @(mglValue[2]), @(mglValue[3])]];
+                }
+            }
+            return self.constantValue;
+        }
+            
+        case NSKeyPathExpressionType: {
+            NSArray *expressionObject;
+            for (NSString *pathComponent in self.keyPath.pathComponents.reverseObjectEnumerator) {
+                if (expressionObject) {
+                    expressionObject = @[@"get", pathComponent, expressionObject];
+                } else {
+                    expressionObject = @[@"get", pathComponent];
+                }
+            }
+            return expressionObject;
+        }
+            
+        case NSFunctionExpressionType: {
+            NSString *function = self.function;
+            NSString *op = MGLExpressionOperatorsByFunctionNames[function];
+            if (op) {
+                NSArray *arguments = self.arguments.mgl_jsonExpressionObject;
+                return [@[op] arrayByAddingObjectsFromArray:arguments];
+            } else if ([function isEqualToString:@"valueForKeyPath:"]) {
+                return @[@"get", self.arguments.firstObject.mgl_jsonExpressionObject, self.operand.mgl_jsonExpressionObject];
+            } else if ([function isEqualToString:@"average:"]) {
+                NSExpression *sum = [NSExpression expressionForFunction:@"sum:" arguments:self.arguments];
+                NSExpression *count = [NSExpression expressionForFunction:@"count:" arguments:self.arguments];
+                return [NSExpression expressionForFunction:@"divide:by:" arguments:@[sum, count]].mgl_jsonExpressionObject;
+            } else if ([function isEqualToString:@"sum:"]) {
+                NSArray *arguments = [self.arguments.firstObject.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
+                return [@[@"+"] arrayByAddingObjectsFromArray:arguments];
+            } else if ([function isEqualToString:@"count:"]) {
+                NSArray *arguments = self.arguments.firstObject.mgl_jsonExpressionObject;
+                return @[@"length", arguments];
+            } else if ([function isEqualToString:@"min:"]) {
+                NSArray *arguments = [self.arguments.firstObject.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
+                return [@[@"min"] arrayByAddingObjectsFromArray:arguments];
+            } else if ([function isEqualToString:@"max:"]) {
+                NSArray *arguments = [self.arguments.firstObject.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
+                return [@[@"max"] arrayByAddingObjectsFromArray:arguments];
+            } else if ([function isEqualToString:@"exp:"]) {
+                return [NSExpression expressionForFunction:@"raise:toPower:" arguments:@[@(M_E), self.arguments.firstObject]].mgl_jsonExpressionObject;
+            } else if ([function isEqualToString:@"ceiling:"]) {
+                return [NSExpression expressionWithFormat:@"trunc:(%@) + TERNARY(modulus:by:(%@, 1) > 0, 1, 0)",
+                        self.arguments.firstObject, self.arguments.firstObject].mgl_jsonExpressionObject;
+            } else if ([function isEqualToString:@"trunc:"]) {
+                return [NSExpression expressionWithFormat:@"%@ - modulus:by:(%@, 1)",
+                        self.arguments.firstObject, self.arguments.firstObject].mgl_jsonExpressionObject;
+            } else if ([function isEqualToString:@"abs:"]) {
+                return [NSExpression expressionWithFormat:@"%@ * TERNARY(%@ > 0, 1, -1)",
+                        self.arguments.firstObject, self.arguments.firstObject].mgl_jsonExpressionObject;
+            } else if ([function isEqualToString:@"floor:"]) {
+                return [NSExpression expressionWithFormat:@"trunc:(%@) - TERNARY(modulus:by:(%@, 1) < 0, 1, 0)",
+                        self.arguments.firstObject, self.arguments.firstObject].mgl_jsonExpressionObject;
+            } else if ([function isEqualToString:@"stringByAppendingString:"]) {
+                NSArray *arguments = self.arguments.mgl_jsonExpressionObject;
+                return [@[@"concat", self.operand.mgl_jsonExpressionObject] arrayByAddingObjectsFromArray:arguments];
+            } else if ([function isEqualToString:@"boolValue"]) {
+                return @[@"to-boolean", self.operand.mgl_jsonExpressionObject];
+            } else if ([function isEqualToString:@"mgl_numberWithFallbackValues:"] ||
+                       [function isEqualToString:@"decimalValue"] ||
+                       [function isEqualToString:@"floatValue"] ||
+                       [function isEqualToString:@"doubleValue"]) {
+                NSArray *arguments = self.arguments.mgl_jsonExpressionObject;
+                return [@[@"to-number", self.operand.mgl_jsonExpressionObject] arrayByAddingObjectsFromArray:arguments];
+            } else if ([function isEqualToString:@"stringValue"]) {
+                return @[@"to-string", self.operand.mgl_jsonExpressionObject];
+            } else if ([function isEqualToString:@"noindex:"]) {
+                return self.arguments.firstObject.mgl_jsonExpressionObject;
+            } else if ([function isEqualToString:@"mgl_interpolateWithCurveType:parameters:stops:"]) {
+                if (self.arguments.count < 3) {
+                    [NSException raise:NSInvalidArgumentException format:
+                     @"Too few arguments to ‘mgl_interpolateWithCurveType:parameters:stops:’ function; expected 3 arguments."];
+                } else if (self.arguments.count > 3) {
+                    [NSException raise:NSInvalidArgumentException format:
+                     @"%lu unexpected arguments to ‘mgl_interpolateWithCurveType:parameters:stops:’ function; expected 3 arguments.",
+                     self.arguments.count - 3];
+                }
+                NSString *curveType = self.arguments.firstObject.constantValue;
+                NSMutableArray *interpolationArray = [NSMutableArray arrayWithObject:curveType];
+                if ([curveType isEqualToString:@"exponential"]) {
+                    id base = [self.arguments[1] mgl_jsonExpressionObject];
+                    [interpolationArray addObject:base];
+                } else if ([curveType isEqualToString:@"cubic-bezier"]) {
+                    NSArray *controlPoints = [self.arguments[1].collection mgl_jsonExpressionObject];
+                    [interpolationArray addObjectsFromArray:controlPoints];
+                }
+                NSMutableArray *expressionObject = [NSMutableArray arrayWithObjects:@"interpolate", interpolationArray, self.operand.mgl_jsonExpressionObject, nil];
+                NSDictionary<NSNumber *, NSExpression *> *stops = self.arguments[2].constantValue;
+                for (NSNumber *key in [stops.allKeys sortedArrayUsingSelector:@selector(compare:)]) {
+                    [expressionObject addObject:key];
+                    [expressionObject addObject:[stops[key] mgl_jsonExpressionObject]];
+                }
+                return expressionObject;
+            } else if ([function isEqualToString:@"mgl_stepWithMinimum:stops:"]) {
+                id minimum = self.arguments.firstObject.mgl_jsonExpressionObject;
+                NSMutableArray *expressionObject = [NSMutableArray arrayWithObjects:@"step", self.operand.mgl_jsonExpressionObject, minimum, nil];
+                NSDictionary<NSNumber *, NSExpression *> *stops = self.arguments[1].constantValue;
+                for (NSNumber *key in [stops.allKeys sortedArrayUsingSelector:@selector(compare:)]) {
+                    [expressionObject addObject:key];
+                    [expressionObject addObject:[stops[key] mgl_jsonExpressionObject]];
+                }
+                return expressionObject;
+            } else if ([function isEqualToString:@"mgl_expressionWithContext:"]) {
+                id context = self.arguments.firstObject;
+                if ([context isKindOfClass:[NSExpression class]]) {
+                    context = [context constantValue];
+                }
+                NSMutableArray *expressionObject = [NSMutableArray arrayWithObjects:@"let", nil];
+                [context enumerateKeysAndObjectsUsingBlock:^(id _Nonnull key, NSExpression * _Nonnull obj, BOOL * _Nonnull stop) {
+                    [expressionObject addObject:key];
+                    [expressionObject addObject:obj.mgl_jsonExpressionObject];
+                }];
+                [expressionObject addObject:self.operand.mgl_jsonExpressionObject];
+                return expressionObject;
+            } else if ([function isEqualToString:@"median:"] ||
+                       [function isEqualToString:@"mode:"] ||
+                       [function isEqualToString:@"stddev:"] ||
+                       [function isEqualToString:@"random"] ||
+                       [function isEqualToString:@"randomn:"] ||
+                       [function isEqualToString:@"now"] ||
+                       [function isEqualToString:@"bitwiseAnd:with:"] ||
+                       [function isEqualToString:@"bitwiseOr:with:"] ||
+                       [function isEqualToString:@"bitwiseXor:with:"] ||
+                       [function isEqualToString:@"leftshift:by:"] ||
+                       [function isEqualToString:@"rightshift:by:"] ||
+                       [function isEqualToString:@"onesComplement:"] ||
+                       [function isEqualToString:@"distanceToLocation:fromLocation:"]) {
+                [NSException raise:NSInvalidArgumentException
+                            format:@"Expression function %@ not yet implemented.", function];
+                return nil;
+            } else {
+                [NSException raise:NSInvalidArgumentException
+                            format:@"Unrecognized expression function %@.", function];
+                return nil;
+            }
+        }
+            
+        case NSConditionalExpressionType: {
+            NSMutableArray *arguments = [NSMutableArray arrayWithObjects:self.predicate.mgl_jsonExpressionObject, self.trueExpression.mgl_jsonExpressionObject, nil];
+            if (self.falseExpression.expressionType == NSConditionalExpressionType) {
+                // Fold nested conditionals into a single case expression.
+                NSArray *falseArguments = self.falseExpression.mgl_jsonExpressionObject;
+                falseArguments = [falseArguments subarrayWithRange:NSMakeRange(1, falseArguments.count - 1)];
+                [arguments addObjectsFromArray:falseArguments];
+            } else {
+                [arguments addObject:self.falseExpression.mgl_jsonExpressionObject];
+            }
+            
+            [arguments insertObject:@"case" atIndex:0];
+            return arguments;
+        }
+            
+        case NSAggregateExpressionType: {
+            NSArray *collection = [self.collection valueForKeyPath:@"mgl_jsonExpressionObject"];
+            return @[@"literal", collection];
+        }
+        
+        case NSEvaluatedObjectExpressionType:
+        case NSUnionSetExpressionType:
+        case NSIntersectSetExpressionType:
+        case NSMinusSetExpressionType:
+        case NSSubqueryExpressionType:
+        case NSAnyKeyExpressionType:
+        case NSBlockExpressionType:
+            [NSException raise:NSInvalidArgumentException
+                        format:@"Expression type %lu not yet implemented.", self.expressionType];
+    }
+    
+    // NSKeyPathSpecifierExpression
+    if (self.expressionType == 10) {
+        return self.description;
+    }
+    // An assignment expression type is present in the BNF grammar, but the
+    // corresponding NSExpressionType value and property getters are missing.
+    if (self.expressionType == 12) {
+        [NSException raise:NSInvalidArgumentException
+                    format:@"Assignment expressions not yet implemented."];
+    }
+    
+    return nil;
+}
+
+@end
diff --git a/platform/darwin/src/NSExpression+MGLPrivateAdditions.h b/platform/darwin/src/NSExpression+MGLPrivateAdditions.h
new file mode 100644
index 0000000000..8d1b4d6af5
--- /dev/null
+++ b/platform/darwin/src/NSExpression+MGLPrivateAdditions.h
@@ -0,0 +1,79 @@
+#import <Foundation/Foundation.h>
+#if TARGET_OS_IPHONE
+    #import <UIKit/UIKit.h>
+#else
+    #import <Cocoa/Cocoa.h>
+#endif
+
+#import "NSExpression+MGLAdditions.h"
+
+#include <mbgl/style/filter.hpp>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface NSObject (MGLExpressionAdditions)
+
+- (NSNumber *)mgl_number;
+- (NSNumber *)mgl_numberWithFallbackValues:(id)fallbackValue, ... NS_REQUIRES_NIL_TERMINATION;
+
+@end
+
+@interface NSExpression (MGLPrivateAdditions)
+
+@property (nonatomic, readonly) mbgl::Value mgl_constantMBGLValue;
+@property (nonatomic, readonly) std::vector<mbgl::Value> mgl_aggregateMBGLValue;
+@property (nonatomic, readonly) mbgl::FeatureType mgl_featureType;
+@property (nonatomic, readonly) std::vector<mbgl::FeatureType> mgl_aggregateFeatureType;
+@property (nonatomic, readonly) mbgl::FeatureIdentifier mgl_featureIdentifier;
+@property (nonatomic, readonly) std::vector<mbgl::FeatureIdentifier> mgl_aggregateFeatureIdentifier;
+
+@end
+
+@interface NSNull (MGLExpressionAdditions)
+
+@property (nonatomic, readonly) id mgl_jsonExpressionObject;
+
+@end
+
+@interface NSString (MGLExpressionAdditions)
+
+@property (nonatomic, readonly) id mgl_jsonExpressionObject;
+
+@end
+
+@interface NSNumber (MGLExpressionAdditions)
+
+- (id)mgl_interpolateWithCurveType:(NSString *)curveType parameters:(NSArray *)parameters stops:(NSDictionary<NSNumber *, id> *)stops;
+- (id)mgl_stepWithMinimum:(id)minimum stops:(NSDictionary<NSNumber *, id> *)stops;
+
+@property (nonatomic, readonly) id mgl_jsonExpressionObject;
+
+@end
+
+@interface NSArray (MGLExpressionAdditions)
+
+@property (nonatomic, readonly) id mgl_jsonExpressionObject;
+
+@end
+
+@interface NSDictionary (MGLExpressionAdditions)
+
+@property (nonatomic, readonly) id mgl_jsonExpressionObject;
+
+@end
+
+@interface MGLColor (MGLExpressionAdditions)
+
+@property (nonatomic, readonly) id mgl_jsonExpressionObject;
+
+@end
+
+@interface NSExpression (MGLExpressionAdditions)
+
+- (NSExpression *)mgl_expressionWithContext:(NSDictionary<NSString *, NSExpression *> *)context;
+
+@end
+
+extern NSArray *MGLSubexpressionsWithJSONObjects(NSArray *objects);
+
+NS_ASSUME_NONNULL_END
diff --git a/platform/darwin/src/NSPredicate+MGLAdditions.h b/platform/darwin/src/NSPredicate+MGLAdditions.h
index fd774dd58b..89e9e65c64 100644
--- a/platform/darwin/src/NSPredicate+MGLAdditions.h
+++ b/platform/darwin/src/NSPredicate+MGLAdditions.h
@@ -1,7 +1,6 @@
 #import <Foundation/Foundation.h>
 
-#import "NSExpression+MGLAdditions.h"
-#include <mbgl/style/filter.hpp>
+#import "NSExpression+MGLPrivateAdditions.h"
 
 @interface NSPredicate (MGLAdditions)
 
@@ -11,3 +10,10 @@
 
 @end
 
+@interface NSPredicate (MGLExpressionAdditions)
+
++ (instancetype)mgl_predicateWithJSONObject:(id)object;
+
+@property (nonatomic, readonly) id mgl_jsonExpressionObject;
+
+@end
diff --git a/platform/darwin/src/NSPredicate+MGLAdditions.mm b/platform/darwin/src/NSPredicate+MGLAdditions.mm
index e0511d8740..3ffe200d01 100644
--- a/platform/darwin/src/NSPredicate+MGLAdditions.mm
+++ b/platform/darwin/src/NSPredicate+MGLAdditions.mm
@@ -228,3 +228,94 @@ public:
 }
 
 @end
+
+@implementation NSPredicate (MGLExpressionAdditions)
+
+NSArray *MGLSubpredicatesWithJSONObjects(NSArray *objects) {
+    NSMutableArray *subpredicates = [NSMutableArray arrayWithCapacity:objects.count];
+    for (id object in objects) {
+        NSPredicate *predicate = [NSPredicate mgl_predicateWithJSONObject:object];
+        [subpredicates addObject:predicate];
+    }
+    return subpredicates;
+}
+
++ (instancetype)mgl_predicateWithJSONObject:(id)object {
+    if ([object isEqual:@YES]) {
+        return [NSPredicate predicateWithValue:YES];
+    }
+    if ([object isEqual:@NO]) {
+        return [NSPredicate predicateWithValue:NO];
+    }
+    
+    NSAssert([object isKindOfClass:[NSArray class]], @"Condition for case expression should be an expression.");
+    NSArray *objects = (NSArray *)object;
+    NSString *op = objects.firstObject;
+    
+    if ([op isEqualToString:@"=="]) {
+        NSArray *subexpressions = MGLSubexpressionsWithJSONObjects([objects subarrayWithRange:NSMakeRange(1, objects.count - 1)]);
+        return [NSPredicate predicateWithFormat:@"%@ == %@" argumentArray:subexpressions];
+    }
+    if ([op isEqualToString:@"!="]) {
+        NSArray *subexpressions = MGLSubexpressionsWithJSONObjects([objects subarrayWithRange:NSMakeRange(1, objects.count - 1)]);
+        return [NSPredicate predicateWithFormat:@"%@ != %@" argumentArray:subexpressions];
+    }
+    if ([op isEqualToString:@"<"]) {
+        NSArray *subexpressions = MGLSubexpressionsWithJSONObjects([objects subarrayWithRange:NSMakeRange(1, objects.count - 1)]);
+        return [NSPredicate predicateWithFormat:@"%@ < %@" argumentArray:subexpressions];
+    }
+    if ([op isEqualToString:@"<="]) {
+        NSArray *subexpressions = MGLSubexpressionsWithJSONObjects([objects subarrayWithRange:NSMakeRange(1, objects.count - 1)]);
+        return [NSPredicate predicateWithFormat:@"%@ <= %@" argumentArray:subexpressions];
+    }
+    if ([op isEqualToString:@">"]) {
+        NSArray *subexpressions = MGLSubexpressionsWithJSONObjects([objects subarrayWithRange:NSMakeRange(1, objects.count - 1)]);
+        return [NSPredicate predicateWithFormat:@"%@ > %@" argumentArray:subexpressions];
+    }
+    if ([op isEqualToString:@">="]) {
+        NSArray *subexpressions = MGLSubexpressionsWithJSONObjects([objects subarrayWithRange:NSMakeRange(1, objects.count - 1)]);
+        return [NSPredicate predicateWithFormat:@"%K >= %@" argumentArray:subexpressions];
+    }
+    if ([op isEqualToString:@"!"]) {
+        NSArray *subpredicates = MGLSubpredicatesWithJSONObjects([objects subarrayWithRange:NSMakeRange(1, objects.count - 1)]);
+        if (subpredicates.count > 1) {
+            NSCompoundPredicate *predicate = [NSCompoundPredicate orPredicateWithSubpredicates:subpredicates];
+            return [NSCompoundPredicate notPredicateWithSubpredicate:predicate];
+        }
+        if (subpredicates.count) {
+            return [NSCompoundPredicate notPredicateWithSubpredicate:subpredicates.firstObject];
+        }
+        return [NSPredicate predicateWithValue:YES];
+    }
+    if ([op isEqualToString:@"all"]) {
+        NSArray *subpredicates = MGLSubpredicatesWithJSONObjects([objects subarrayWithRange:NSMakeRange(1, objects.count - 1)]);
+        return [NSCompoundPredicate andPredicateWithSubpredicates:subpredicates];
+    }
+    if ([op isEqualToString:@"any"]) {
+        NSArray *subpredicates = MGLSubpredicatesWithJSONObjects([objects subarrayWithRange:NSMakeRange(1, objects.count - 1)]);
+        return [NSCompoundPredicate orPredicateWithSubpredicates:subpredicates];
+    }
+    
+    NSAssert(NO, @"Unrecognized expression conditional operator %@.", op);
+    return nil;
+}
+
+- (id)mgl_jsonExpressionObject {
+    if ([self isEqual:[NSPredicate predicateWithValue:YES]]) {
+        return @YES;
+    }
+    if ([self isEqual:[NSPredicate predicateWithValue:NO]]) {
+        return @NO;
+    }
+    
+    if ([self.predicateFormat hasPrefix:@"BLOCKPREDICATE("]) {
+        [NSException raise:NSInvalidArgumentException
+                    format:@"Block-based predicates are not supported."];
+    }
+    
+    [NSException raise:NSInvalidArgumentException
+                format:@"Unrecognized predicate type."];
+    return nil;
+}
+
+@end