to_underlying.h revision 1.1.1.2
1// -*- C++ -*- 2//===----------------------------------------------------------------------===// 3// 4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 5// See https://llvm.org/LICENSE.txt for license information. 6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 7// 8//===----------------------------------------------------------------------===// 9 10#ifndef _LIBCPP___UTILITY_TO_UNDERLYING_H 11#define _LIBCPP___UTILITY_TO_UNDERLYING_H 12 13#include <__config> 14#include <__type_traits/underlying_type.h> 15 16#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 17# pragma GCC system_header 18#endif 19 20_LIBCPP_BEGIN_NAMESPACE_STD 21 22#ifndef _LIBCPP_CXX03_LANG 23template <class _Tp> 24_LIBCPP_INLINE_VISIBILITY constexpr typename underlying_type<_Tp>::type 25__to_underlying(_Tp __val) noexcept { 26 return static_cast<typename underlying_type<_Tp>::type>(__val); 27} 28#endif // !_LIBCPP_CXX03_LANG 29 30#if _LIBCPP_STD_VER > 20 31template <class _Tp> 32_LIBCPP_NODISCARD_EXT _LIBCPP_INLINE_VISIBILITY constexpr underlying_type_t<_Tp> 33to_underlying(_Tp __val) noexcept { 34 return _VSTD::__to_underlying(__val); 35} 36#endif 37 38_LIBCPP_END_NAMESPACE_STD 39 40#endif // _LIBCPP___UTILITY_TO_UNDERLYING_H 41