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_NULL_POINTER_H
10 #define _LIBCPP___TYPE_TRAITS_IS_NULL_POINTER_H
11 
12 #include <__config>
13 #include <__type_traits/integral_constant.h>
14 #include <__type_traits/remove_cv.h>
15 #include <cstddef>
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 template <class _Tp>
24 struct __is_nullptr_t_impl : public false_type {};
25 template <>
26 struct __is_nullptr_t_impl<nullptr_t> : public true_type {};
27 
28 template <class _Tp>
29 struct _LIBCPP_TEMPLATE_VIS __is_nullptr_t : public __is_nullptr_t_impl<__remove_cv_t<_Tp> > {};
30 
31 #if _LIBCPP_STD_VER >= 14
32 template <class _Tp>
33 struct _LIBCPP_TEMPLATE_VIS is_null_pointer : public __is_nullptr_t_impl<__remove_cv_t<_Tp> > {};
34 
35 #  if _LIBCPP_STD_VER >= 17
36 template <class _Tp>
37 inline constexpr bool is_null_pointer_v = is_null_pointer<_Tp>::value;
38 #  endif
39 #endif // _LIBCPP_STD_VER >= 14
40 
41 _LIBCPP_END_NAMESPACE_STD
42 
43 #endif // _LIBCPP___TYPE_TRAITS_IS_NULL_POINTER_H
44