[gcc.git] / gcc / testsuite / g++.dg / cpp0x / decltype5.C

// { dg-do compile { target c++11 } }

template<typename T, typename U> 
struct is_same 
{
  static const bool value = false;
};

template<typename T>
struct is_same<T, T>
{
  static const bool value = true;
};

#define CHECK_DECLTYPE(DECLTYPE,RESULT) \
  static_assert(is_same< DECLTYPE , RESULT >::value, #RESULT)

template<typename F> F create_a();

template<typename F, typename T1>
decltype(create_a<F&>()(create_a<const T1&>())) forward(F f, const T1& a1)
{
  return f(a1);
}

struct identity {
  template<typename T>
  const T& operator()(const T& x) { return x; }
};


identity id;
int i;
float f;

CHECK_DECLTYPE(decltype(forward(id, i)), const int&);
CHECK_DECLTYPE(decltype(forward(id, f)), const float&);
Commit	Line	Data
4b2e63de	1	// { dg-do compile { target c++11 } }
3ad6a8e1 DG	2
	3	template<typename T, typename U>
	4	struct is_same
	5	{
	6	static const bool value = false;
	7	};
	8
	9	template<typename T>
	10	struct is_same<T, T>
	11	{
	12	static const bool value = true;
	13	};
	14
	15	#define CHECK_DECLTYPE(DECLTYPE,RESULT) \
	16	static_assert(is_same< DECLTYPE , RESULT >::value, #RESULT)
	17
	18	template<typename F> F create_a();
	19
	20	template<typename F, typename T1>
	21	decltype(create_a<F&>()(create_a<const T1&>())) forward(F f, const T1& a1)
	22	{
	23	return f(a1);
	24	}
	25
	26	struct identity {
	27	template<typename T>
	28	const T& operator()(const T& x) { return x; }
	29	};
	30
	31
	32	identity id;
	33	int i;
	34	float f;
	35
	36	CHECK_DECLTYPE(decltype(forward(id, i)), const int&);
	37	CHECK_DECLTYPE(decltype(forward(id, f)), const float&);