template<class tp, class val_tp = typename tp::val> class foo 
{
	// ....
};

class bar : public foo<bar>  // error
{
public:
	typedef int val;
	// ....
};

template<class tp, void (tp::*)()> class foo 
{
	//...
};

class bar : public foo<bar, &bar::baz> // error
{
public:
	void baz();
	//...
};