1c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant//===----------------------------------------------------------------------===// 2c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant// 3c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant// The LLVM Compiler Infrastructure 4c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant// 5b64f8b07c104c6cc986570ac8ee0ed16a9f23976Howard Hinnant// This file is dual licensed under the MIT and the University of Illinois Open 6b64f8b07c104c6cc986570ac8ee0ed16a9f23976Howard Hinnant// Source Licenses. See LICENSE.TXT for details. 7c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant// 8c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant//===----------------------------------------------------------------------===// 9c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant 10c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant// <functional> 11c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant 12c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant// reference_wrapper 13c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant 14c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant// has weak result type 15c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant 16c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant#include <functional> 17c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant#include <type_traits> 18c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant 19c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnantclass functor1 20c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant : public std::unary_function<int, char> 21c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant{ 22c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant}; 23c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant 24c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnantclass functor2 25c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant : public std::binary_function<char, int, double> 26c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant{ 27c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant}; 28c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant 29c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnantclass functor3 30c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant : public std::unary_function<char, int>, 31c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant public std::binary_function<char, int, double> 32c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant{ 33c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnantpublic: 34c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant typedef float result_type; 35c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant}; 36c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant 37c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnantclass functor4 38c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant : public std::unary_function<char, int>, 39c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant public std::binary_function<char, int, double> 40c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant{ 41c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnantpublic: 42c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant}; 43c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant 44c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnantclass C {}; 45c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant 46c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnanttemplate <class T> 47c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnantstruct has_result_type 48c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant{ 49c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnantprivate: 50c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant struct two {char _; char __;}; 51c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant template <class U> static two test(...); 52c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant template <class U> static char test(typename U::result_type* = 0); 53c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnantpublic: 54c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static const bool value = sizeof(test<T>(0)) == 1; 55c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant}; 56c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant 57c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnantint main() 58c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant{ 59c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert((std::is_same<std::reference_wrapper<functor1>::result_type, 60c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant char>::value), ""); 61c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert((std::is_same<std::reference_wrapper<functor2>::result_type, 62c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant double>::value), ""); 63c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert((std::is_same<std::reference_wrapper<functor3>::result_type, 64c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant float>::value), ""); 65c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert((std::is_same<std::reference_wrapper<void()>::result_type, 66c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant void>::value), ""); 67c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert((std::is_same<std::reference_wrapper<int*(double*)>::result_type, 68c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant int*>::value), ""); 69c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert((std::is_same<std::reference_wrapper<void(*)()>::result_type, 70c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant void>::value), ""); 71c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert((std::is_same<std::reference_wrapper<int*(*)(double*)>::result_type, 72c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant int*>::value), ""); 73c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert((std::is_same<std::reference_wrapper<int*(C::*)(double*)>::result_type, 74c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant int*>::value), ""); 75c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert((std::is_same<std::reference_wrapper<int (C::*)(double*) const volatile>::result_type, 76c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant int>::value), ""); 77c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert((std::is_same<std::reference_wrapper<C()>::result_type, 78c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant C>::value), ""); 79c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert(has_result_type<std::reference_wrapper<functor3> >::value, ""); 80c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert(!has_result_type<std::reference_wrapper<functor4> >::value, ""); 81c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant static_assert(!has_result_type<std::reference_wrapper<C> >::value, ""); 82c52f43e72dfcea03037729649da84c23b3beb04aHoward Hinnant} 83