libstdc++

utility
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1 // <utility> -*- C++ -*-
2
3 // Copyright (C) 2001-2013 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24
25 /*
26 *
27 * Copyright (c) 1994
28 * Hewlett-Packard Company
29 *
30 * Permission to use, copy, modify, distribute and sell this software
31 * and its documentation for any purpose is hereby granted without fee,
32 * provided that the above copyright notice appear in all copies and
33 * that both that copyright notice and this permission notice appear
34 * in supporting documentation. Hewlett-Packard Company makes no
35 * representations about the suitability of this software for any
36 * purpose. It is provided "as is" without express or implied warranty.
37 *
38 *
39 * Copyright (c) 1996,1997
40 * Silicon Graphics Computer Systems, Inc.
41 *
42 * Permission to use, copy, modify, distribute and sell this software
43 * and its documentation for any purpose is hereby granted without fee,
44 * provided that the above copyright notice appear in all copies and
45 * that both that copyright notice and this permission notice appear
46 * in supporting documentation. Silicon Graphics makes no
47 * representations about the suitability of this software for any
48 * purpose. It is provided "as is" without express or implied warranty.
49 */
50
51 /** @file include/utility
52 * This is a Standard C++ Library header.
53 */
54
55 #ifndef _GLIBCXX_UTILITY
56 #define _GLIBCXX_UTILITY 1
57
58 #pragma GCC system_header
59
60 /**
61 * @defgroup utilities Utilities
62 *
63 * Components deemed generally useful. Includes pair, tuple,
64 * forward/move helpers, ratio, function object, metaprogramming and
65 * type traits, time, date, and memory functions.
66 */
67
68 #include <bits/c++config.h>
69 #include <bits/stl_relops.h>
70 #include <bits/stl_pair.h>
71
72 #if __cplusplus >= 201103L
73 #include <bits/move.h>
74 #include <initializer_list>
75
76 namespace std _GLIBCXX_VISIBILITY(default)
77 {
78 _GLIBCXX_BEGIN_NAMESPACE_VERSION
79
80 template<class _Tp>
81 class tuple_size;
82
83 template<std::size_t _Int, class _Tp>
84 class tuple_element;
85
86 // Various functions which give std::pair a tuple-like interface.
87 template<class _Tp1, class _Tp2>
88 struct tuple_size<std::pair<_Tp1, _Tp2>>
89 : public integral_constant<std::size_t, 2> { };
90
91 template<class _Tp1, class _Tp2>
92 struct tuple_element<0, std::pair<_Tp1, _Tp2>>
93 { typedef _Tp1 type; };
94
95 template<class _Tp1, class _Tp2>
96 struct tuple_element<1, std::pair<_Tp1, _Tp2>>
97 { typedef _Tp2 type; };
98
99 template<std::size_t _Int>
100 struct __pair_get;
101
102 template<>
103 struct __pair_get<0>
104 {
105 template<typename _Tp1, typename _Tp2>
106 static constexpr _Tp1&
107 __get(std::pair<_Tp1, _Tp2>& __pair) noexcept
108 { return __pair.first; }
109
110 template<typename _Tp1, typename _Tp2>
111 static constexpr _Tp1&&
112 __move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept
113 { return std::forward<_Tp1>(__pair.first); }
114
115 template<typename _Tp1, typename _Tp2>
116 static constexpr const _Tp1&
117 __const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept
118 { return __pair.first; }
119 };
120
121 template<>
122 struct __pair_get<1>
123 {
124 template<typename _Tp1, typename _Tp2>
125 static constexpr _Tp2&
126 __get(std::pair<_Tp1, _Tp2>& __pair) noexcept
127 { return __pair.second; }
128
129 template<typename _Tp1, typename _Tp2>
130 static constexpr _Tp2&&
131 __move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept
132 { return std::forward<_Tp2>(__pair.second); }
133
134 template<typename _Tp1, typename _Tp2>
135 static constexpr const _Tp2&
136 __const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept
137 { return __pair.second; }
138 };
139
140 template<std::size_t _Int, class _Tp1, class _Tp2>
141 constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&
142 get(std::pair<_Tp1, _Tp2>& __in) noexcept
143 { return __pair_get<_Int>::__get(__in); }
144
145 template<std::size_t _Int, class _Tp1, class _Tp2>
146 constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&&
147 get(std::pair<_Tp1, _Tp2>&& __in) noexcept
148 { return __pair_get<_Int>::__move_get(std::move(__in)); }
149
150 template<std::size_t _Int, class _Tp1, class _Tp2>
151 constexpr const typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&
152 get(const std::pair<_Tp1, _Tp2>& __in) noexcept
153 { return __pair_get<_Int>::__const_get(__in); }
154
155 _GLIBCXX_END_NAMESPACE_VERSION
156 } // namespace
157
158 #endif
159
160 #endif /* _GLIBCXX_UTILITY */