LLVM RTTI Pattern

1class Shape {
2 public:
3  enum ShapeKind { SK_Circle, SK_Square };
4  ShapeKind getKind() const {
5    return Kind;
6  }
7  Shape(ShapeKind K) : Kind(K) {}
8 private:
9  const ShapeKind Kind;
10};
11class Circle : public Shape {
12 public:
13  Circle() : Shape(SK_Circle) {}
14  static bool classof(const Shape *S) {
15    return S->getKind() == SK_Circle;
16  }
17};