[core] Convert "legacy" filters directly into expressions (#11610)

Ports the specialized filter-* expressions from GL JS, adding them to src/mbgl/style/expression/compound_expression.cpp

1 files changed, 13 insertions, 2 deletions

diff --git a/include/mbgl/style/expression/compound_expression.hpp b/include/mbgl/style/expression/compound_expression.hpp
index 6baaae862f..431afb4d13 100644
--- a/include/mbgl/style/expression/compound_expression.hpp
+++ b/include/mbgl/style/expression/compound_expression.hpp
@@ -36,7 +36,7 @@ template <typename T>
 struct Varargs : std::vector<T> { using std::vector<T>::vector; };
 
 namespace detail {
-// Base class for the Signature<Fn> structs that are used to determine the
+// Base class for the Signature<Fn> structs that are used to determine
 // each CompoundExpression definition's type::Type data from the type of its
 // "evaluate" function.
 struct SignatureBase {
@@ -137,10 +137,21 @@ ParseResult parseCompoundExpression(const std::string name, const mbgl::style::c
 ParseResult createCompoundExpression(const CompoundExpressionRegistry::Definition& definition,
                                      std::vector<std::unique_ptr<Expression>> args,
                                      ParsingContext& ctx);
-    
+
 ParseResult createCompoundExpression(const std::string& name,
                                      std::vector<std::unique_ptr<Expression>> args,
                                      ParsingContext& ctx);
+// Convenience method for use expressions that have 0, 1, or 2 args.
+ParseResult createCompoundExpression(const std::string& name, ParsingContext& ctx);
+
+ParseResult createCompoundExpression(const std::string& name,
+                                     std::unique_ptr<Expression> arg1,
+                                     ParsingContext& ctx);
+
+ParseResult createCompoundExpression(const std::string& name,
+                                     std::unique_ptr<Expression> arg1,
+                                     std::unique_ptr<Expression> arg2,
+                                     ParsingContext& ctx);
 
 } // namespace expression
 } // namespace style