Home | History | Annotate | Line # | Download | only in __utility 
      1 // -*- C++ -*-
      2 //===----------------- __utility/to_underlying.h --------------------------===//
      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>
     15 
     16 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
     17 #pragma GCC system_header
     18 #endif
     19 
     20 _LIBCPP_PUSH_MACROS
     21 #include <__undef_macros>
     22 
     23 _LIBCPP_BEGIN_NAMESPACE_STD
     24 
     25 #ifndef _LIBCPP_CXX03_LANG
     26 template <class _Tp>
     27 _LIBCPP_INLINE_VISIBILITY constexpr typename underlying_type<_Tp>::type
     28 __to_underlying(_Tp __val) noexcept {
     29   return static_cast<typename underlying_type<_Tp>::type>(__val);
     30 }
     31 #endif // !_LIBCPP_CXX03_LANG
     32 
     33 #if _LIBCPP_STD_VER > 20
     34 template <class _Tp>
     35 _LIBCPP_NODISCARD_EXT _LIBCPP_INLINE_VISIBILITY constexpr underlying_type_t<_Tp>
     36 to_underlying(_Tp __val) noexcept {
     37   return _VSTD::__to_underlying(__val);
     38 }
     39 #endif
     40 
     41 _LIBCPP_END_NAMESPACE_STD
     42 
     43 _LIBCPP_POP_MACROS
     44 
     45 #endif // _LIBCPP___UTILITY_TO_UNDERLYING_H
     46