| // Copyright (C) 2019-2021 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library is free |
| // software; you can redistribute it and/or modify it under the |
| // terms of the GNU General Public License as published by the |
| // Free Software Foundation; either version 3, or (at your option) |
| // any later version. |
| |
| // This library is distributed in the hope that it will be useful, |
| // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| // GNU General Public License for more details. |
| |
| // You should have received a copy of the GNU General Public License along |
| // with this library; see the file COPYING3. If not see |
| // <http://www.gnu.org/licenses/>. |
| |
| // { dg-do compile { target c++11 } } |
| |
| #include <type_traits> |
| |
| // Test for SFINAE-friendly underlying_type |
| |
| template<typename T, typename = typename std::underlying_type<T>::type> |
| constexpr bool is_enum(int) { return true; } |
| |
| template<typename T> |
| constexpr bool is_enum(...) { return false; } |
| |
| void |
| test01() |
| { |
| enum E { }; |
| static_assert( is_enum<E>(0), ""); |
| |
| static_assert( !is_enum<void>(0), ""); |
| static_assert( !is_enum<int>(0), ""); |
| static_assert( !is_enum<long>(0), ""); |
| static_assert( !is_enum<int*>(0), ""); |
| static_assert( !is_enum<int[]>(0), ""); |
| static_assert( !is_enum<const int*>(0), ""); |
| static_assert( !is_enum<const int&>(0), ""); |
| static_assert( !is_enum<int()>(0), ""); |
| static_assert( !is_enum<int(&)()>(0), ""); |
| static_assert( !is_enum<int(*)()>(0), ""); |
| struct S { }; |
| static_assert( !is_enum<S>(0), ""); |
| static_assert( !is_enum<S&>(0), ""); |
| static_assert( !is_enum<S*>(0), ""); |
| static_assert( !is_enum<int S::*>(0), ""); |
| static_assert( !is_enum<int (S::*)()>(0), ""); |
| } |