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#ifndef _LIBCPP___TYPE_TRAITS_IS_VOID_H
10#define _LIBCPP___TYPE_TRAITS_IS_VOID_H
11
12#include <__config>
13#include <__type_traits/integral_constant.h>
14#include <__type_traits/is_same.h>
15#include <__type_traits/remove_cv.h>
16
17#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
18#  pragma GCC system_header
19#endif
20
21_LIBCPP_BEGIN_NAMESPACE_STD
22
23#if __has_builtin(__is_void)
24
25template <class _Tp>
26struct _LIBCPP_TEMPLATE_VIS is_void : _BoolConstant<__is_void(_Tp)> {};
27
28#  if _LIBCPP_STD_VER >= 17
29template <class _Tp>
30inline constexpr bool is_void_v = __is_void(_Tp);
31#  endif
32
33#else
34
35template <class _Tp>
36struct _LIBCPP_TEMPLATE_VIS is_void : public is_same<__remove_cv_t<_Tp>, void> {};
37
38#  if _LIBCPP_STD_VER >= 17
39template <class _Tp>
40inline constexpr bool is_void_v = is_void<_Tp>::value;
41#  endif
42
43#endif // __has_builtin(__is_void)
44
45_LIBCPP_END_NAMESPACE_STD
46
47#endif // _LIBCPP___TYPE_TRAITS_IS_VOID_H
48