xref: /freebsd/contrib/llvm-project/libcxx/include/__functional/ranges_operations.h (revision b64c5a0ace59af62eff52bfe110a521dc73c937b)
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___FUNCTIONAL_RANGES_OPERATIONS_H
11 #define _LIBCPP___FUNCTIONAL_RANGES_OPERATIONS_H
12 
13 #include <__concepts/equality_comparable.h>
14 #include <__concepts/totally_ordered.h>
15 #include <__config>
16 #include <__type_traits/desugars_to.h>
17 #include <__utility/forward.h>
18 
19 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
20 #  pragma GCC system_header
21 #endif
22 
23 _LIBCPP_BEGIN_NAMESPACE_STD
24 
25 #if _LIBCPP_STD_VER >= 20
26 
27 namespace ranges {
28 
29 struct equal_to {
30   template <class _Tp, class _Up>
31     requires equality_comparable_with<_Tp, _Up>
32   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t, _Up&& __u) const
33       noexcept(noexcept(bool(std::forward<_Tp>(__t) == std::forward<_Up>(__u)))) {
34     return std::forward<_Tp>(__t) == std::forward<_Up>(__u);
35   }
36 
37   using is_transparent = void;
38 };
39 
40 struct not_equal_to {
41   template <class _Tp, class _Up>
42     requires equality_comparable_with<_Tp, _Up>
43   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t, _Up&& __u) const
44       noexcept(noexcept(bool(!(std::forward<_Tp>(__t) == std::forward<_Up>(__u))))) {
45     return !(std::forward<_Tp>(__t) == std::forward<_Up>(__u));
46   }
47 
48   using is_transparent = void;
49 };
50 
51 struct less {
52   template <class _Tp, class _Up>
53     requires totally_ordered_with<_Tp, _Up>
54   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t, _Up&& __u) const
55       noexcept(noexcept(bool(std::forward<_Tp>(__t) < std::forward<_Up>(__u)))) {
56     return std::forward<_Tp>(__t) < std::forward<_Up>(__u);
57   }
58 
59   using is_transparent = void;
60 };
61 
62 struct less_equal {
63   template <class _Tp, class _Up>
64     requires totally_ordered_with<_Tp, _Up>
65   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t, _Up&& __u) const
66       noexcept(noexcept(bool(!(std::forward<_Up>(__u) < std::forward<_Tp>(__t))))) {
67     return !(std::forward<_Up>(__u) < std::forward<_Tp>(__t));
68   }
69 
70   using is_transparent = void;
71 };
72 
73 struct greater {
74   template <class _Tp, class _Up>
75     requires totally_ordered_with<_Tp, _Up>
76   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t, _Up&& __u) const
77       noexcept(noexcept(bool(std::forward<_Up>(__u) < std::forward<_Tp>(__t)))) {
78     return std::forward<_Up>(__u) < std::forward<_Tp>(__t);
79   }
80 
81   using is_transparent = void;
82 };
83 
84 struct greater_equal {
85   template <class _Tp, class _Up>
86     requires totally_ordered_with<_Tp, _Up>
87   [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr bool operator()(_Tp&& __t, _Up&& __u) const
88       noexcept(noexcept(bool(!(std::forward<_Tp>(__t) < std::forward<_Up>(__u))))) {
89     return !(std::forward<_Tp>(__t) < std::forward<_Up>(__u));
90   }
91 
92   using is_transparent = void;
93 };
94 
95 } // namespace ranges
96 
97 // For ranges we do not require that the types on each side of the equality
98 // operator are of the same type
99 template <class _Tp, class _Up>
100 inline const bool __desugars_to_v<__equal_tag, ranges::equal_to, _Tp, _Up> = true;
101 
102 template <class _Tp, class _Up>
103 inline const bool __desugars_to_v<__less_tag, ranges::less, _Tp, _Up> = true;
104 
105 #endif // _LIBCPP_STD_VER >= 20
106 
107 _LIBCPP_END_NAMESPACE_STD
108 
109 #endif // _LIBCPP___FUNCTIONAL_RANGES_OPERATIONS_H
110