+class ReferenceValidator: private Validator
+{
+public:
+ void apply(Stage &s) { stage = &s; s.content.visit(*this); }
+
+private:
+ virtual void visit(BasicTypeDeclaration &);
+ virtual void visit(ImageTypeDeclaration &);
+ virtual void visit(VariableReference &);
+ virtual void visit(MemberAccess &);
+ virtual void visit(InterfaceBlockReference &);
+ virtual void visit(FunctionCall &);
+ virtual void visit(VariableDeclaration &);
+ virtual void visit(InterfaceBlock &);
+ virtual void visit(FunctionDeclaration &);
+};
+
+class ExpressionValidator: private Validator
+{
+public:
+ void apply(Stage &s) { stage = &s; s.content.visit(*this); }
+
+private:
+ virtual void visit(Swizzle &);
+ virtual void visit(UnaryExpression &);
+ virtual void visit(BinaryExpression &);
+ virtual void visit(Assignment &);
+ virtual void visit(TernaryExpression &);
+ virtual void visit(VariableDeclaration &);
+};
+