[core] Replace expressions RTTI with enums + static cast

1 files changed, 6 insertions, 4 deletions

diff --git a/include/mbgl/style/expression/let.hpp b/include/mbgl/style/expression/let.hpp
index d0210d8bba..d11ba1b976 100644
--- a/include/mbgl/style/expression/let.hpp
+++ b/include/mbgl/style/expression/let.hpp
@@ -16,7 +16,7 @@ public:
     using Bindings = std::map<std::string, std::shared_ptr<Expression>>;
     
     Let(Bindings bindings_, std::unique_ptr<Expression> result_) :
-        Expression(result_->getType()),
+        Expression(Kind::Let, result_->getType()),
         bindings(std::move(bindings_)),
         result(std::move(result_))
     {}
@@ -27,7 +27,8 @@ public:
     void eachChild(const std::function<void(const Expression&)>&) const override;
 
     bool operator==(const Expression& e) const override {
-        if (auto rhs = dynamic_cast<const Let*>(&e)) {
+        if (e.getKind() == Kind::Let) {
+            auto rhs = static_cast<const Let*>(&e);
             return *result == *(rhs->result);
         }
         return false;
@@ -49,7 +50,7 @@ private:
 class Var : public Expression {
 public:
     Var(std::string name_, std::shared_ptr<Expression> value_) :
-        Expression(value_->getType()),
+        Expression(Kind::Var, value_->getType()),
         name(std::move(name_)),
         value(value_)
     {}
@@ -60,7 +61,8 @@ public:
     void eachChild(const std::function<void(const Expression&)>&) const override;
 
     bool operator==(const Expression& e) const override {
-        if (auto rhs = dynamic_cast<const Var*>(&e)) {
+        if (e.getKind() == Kind::Var) {
+            auto rhs = static_cast<const Var*>(&e);
             return *value == *(rhs->value);
         }
         return false;