1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // UNSUPPORTED: c++03 10 11 // <system_error> 12 13 // template <> struct is_error_code_enum<> : public false_type {}; 14 15 #include <cstddef> 16 #include <string> 17 #include <system_error> 18 19 #include "test_macros.h" 20 21 template <bool Expected, class T> 22 void 23 test() 24 { 25 static_assert((std::is_error_code_enum<T>::value == Expected), ""); 26 #if TEST_STD_VER > 14 27 static_assert((std::is_error_code_enum_v<T> == Expected), ""); 28 ASSERT_SAME_TYPE(decltype(std::is_error_code_enum_v<T>), const bool); 29 #endif 30 } 31 32 class A { 33 A(); 34 operator std::error_code () const { return std::error_code(); } 35 }; 36 37 // Specialize the template for my class 38 template <> 39 struct std::is_error_code_enum<A> : public std::true_type {}; 40 41 int main(int, char**) 42 { 43 test<false, void>(); 44 test<false, int>(); 45 test<false, std::nullptr_t>(); 46 test<false, std::string>(); 47 48 test<true, A>(); 49 50 return 0; 51 } 52