1 files changed, 4 insertions, 0 deletions
diff --git a/include/mbgl/style/function/source_function.hpp b/include/mbgl/style/function/source_function.hpp
index 02e4b604e2..bd7b109fd8 100644
--- a/include/mbgl/style/function/source_function.hpp
+++ b/include/mbgl/style/function/source_function.hpp
@@ -57,6 +57,10 @@ public:
         return defaultValue ? *defaultValue : finalDefaultValue;
     }
 
+    std::vector<optional<T>> possibleOutputs() const {
+        return expression::fromExpressionValues<T>(expression->possibleOutputs());
+    }
+
     friend bool operator==(const SourceFunction& lhs,
                            const SourceFunction& rhs) {
         return *lhs.expression == *rhs.expression;