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_INTEGRAL_CONSTANT_H
10 #define _LIBCPP___TYPE_TRAITS_INTEGRAL_CONSTANT_H
11 
12 #include <__config>
13 
14 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
15 #  pragma GCC system_header
16 #endif
17 
18 _LIBCPP_BEGIN_NAMESPACE_STD
19 
20 template <class _Tp, _Tp __v>
21 struct _LIBCPP_TEMPLATE_VIS integral_constant
22 {
23   static _LIBCPP_CONSTEXPR const _Tp      value = __v;
24   typedef _Tp               value_type;
25   typedef integral_constant type;
26   _LIBCPP_INLINE_VISIBILITY
27   _LIBCPP_CONSTEXPR operator value_type() const _NOEXCEPT {return value;}
28 #if _LIBCPP_STD_VER > 11
29   _LIBCPP_INLINE_VISIBILITY
30   constexpr value_type operator ()() const _NOEXCEPT {return value;}
31 #endif
32 };
33 
34 template <class _Tp, _Tp __v>
35 _LIBCPP_CONSTEXPR const _Tp integral_constant<_Tp, __v>::value;
36 
37 typedef integral_constant<bool, true>  true_type;
38 typedef integral_constant<bool, false> false_type;
39 
40 template <bool _Val>
41 using _BoolConstant _LIBCPP_NODEBUG = integral_constant<bool, _Val>;
42 
43 #if _LIBCPP_STD_VER > 14
44 template <bool __b>
45 using bool_constant = integral_constant<bool, __b>;
46 #endif
47 
48 _LIBCPP_END_NAMESPACE_STD
49 
50 #endif // _LIBCPP___TYPE_TRAITS_INTEGRAL_CONSTANT_H
51