Mercurial > hg > CbC > CbC_gcc
view gcc/testsuite/g++.dg/cpp0x/sfinae3.C @ 131:84e7813d76e9
gcc-8.2
author | mir3636 |
---|---|
date | Thu, 25 Oct 2018 07:37:49 +0900 |
parents | 04ced10e8804 |
children |
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// { dg-do compile { target c++11 } } namespace std { template <class T> T&& declval(); } template<typename _Tp, typename... _Args> class is_constructible_mini { typedef char __one; typedef struct { char __arr[2]; } __two; template<typename _Tp1, typename... _Args1> static decltype(::new _Tp1(std::declval<_Args1>()...), __one()) __test(int); template<typename, typename...> static __two __test(...); public: static const bool value = sizeof(__test<_Tp, _Args...>(0)) == 1; }; /* template<typename _Tp> class is_constructible_mini<_Tp> { typedef char __one; typedef struct { char __arr[2]; } __two; template<typename _Tp1> static decltype(::new _Tp1, __one()) __test(int); template<typename> static __two __test(...); public: static const bool value = sizeof(__test<typename std::remove_cv<_Tp>::type>(0)) == 1; }; */ struct A { A(int); }; struct B { }; static_assert( is_constructible_mini<A, int>::value, ""); static_assert( is_constructible_mini<A, A>::value, ""); static_assert( !is_constructible_mini<A, int, double>::value, ""); static_assert( !is_constructible_mini<A>::value, ""); // doesn't compile without the // partial specialization static_assert( is_constructible_mini<B>::value, ""); static_assert( is_constructible_mini<const B>::value, "");