#include <iostream>

struct IShape {
	virtual void draw() const = 0;
	virtual ~IShape() = default;
};

class Circle : public IShape {
public:
	void draw() const override {
		std::cout << "Circle::draw()\n";
	}
};


template<typename T>
class Wrapper {
	T* impl;

public:
	Wrapper(T* obj) : impl(obj) {}

	T* operator->() { return impl; }
	const T* operator->() const { return impl; }

	operator T*() { return impl; }
	operator const T*() const { return impl; }

	operator T&() { return *impl; }
	operator const T&() const { return *impl; }
};

void render_shape_by_ptr(IShape* shape) {
	shape->draw();
}

void render_shape_by_ref(IShape& shape) {
	shape.draw();
}

int main() {
	Circle c;
	Wrapper<IShape> w(&c);

	w->draw();

	render_shape_by_ptr(w);

	render_shape_by_ref(w);
}