1// <utility> -*- C++ -*-
2
3// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
4// 2010, 2011
5// Free Software Foundation, Inc.
6//
7// This file is part of the GNU ISO C++ Library.  This library is free
8// software; you can redistribute it and/or modify it under the
9// terms of the GNU General Public License as published by the
10// Free Software Foundation; either version 3, or (at your option)
11// any later version.
12
13// This library is distributed in the hope that it will be useful,
14// but WITHOUT ANY WARRANTY; without even the implied warranty of
15// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16// GNU General Public License for more details.
17
18// Under Section 7 of GPL version 3, you are granted additional
19// permissions described in the GCC Runtime Library Exception, version
20// 3.1, as published by the Free Software Foundation.
21
22// You should have received a copy of the GNU General Public License and
23// a copy of the GCC Runtime Library Exception along with this program;
24// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
25// <http://www.gnu.org/licenses/>.
26
27/*
28 *
29 * Copyright (c) 1994
30 * Hewlett-Packard Company
31 *
32 * Permission to use, copy, modify, distribute and sell this software
33 * and its documentation for any purpose is hereby granted without fee,
34 * provided that the above copyright notice appear in all copies and
35 * that both that copyright notice and this permission notice appear
36 * in supporting documentation.  Hewlett-Packard Company makes no
37 * representations about the suitability of this software for any
38 * purpose.  It is provided "as is" without express or implied warranty.
39 *
40 *
41 * Copyright (c) 1996,1997
42 * Silicon Graphics Computer Systems, Inc.
43 *
44 * Permission to use, copy, modify, distribute and sell this software
45 * and its documentation for any purpose is hereby granted without fee,
46 * provided that the above copyright notice appear in all copies and
47 * that both that copyright notice and this permission notice appear
48 * in supporting documentation.  Silicon Graphics makes no
49 * representations about the suitability of this software for any
50 * purpose.  It is provided "as is" without express or implied warranty.
51 */
52
53/** @file include/utility
54 *  This is a Standard C++ Library header.
55 */
56
57#ifndef _GLIBCXX_UTILITY
58#define _GLIBCXX_UTILITY 1
59
60#pragma GCC system_header
61
62/**
63 * @defgroup utilities Utilities
64 *
65 * Components deemed generally useful. Includes pair, tuple,
66 * forward/move helpers, ratio, function object, metaprogramming and
67 * type traits, time, date, and memory functions.
68 */
69
70#include <bits/c++config.h>
71#include <bits/stl_relops.h>
72#include <bits/stl_pair.h>
73
74#ifdef __GXX_EXPERIMENTAL_CXX0X__
75#include <bits/move.h>
76#include <initializer_list>
77
78namespace std _GLIBCXX_VISIBILITY(default)
79{
80_GLIBCXX_BEGIN_NAMESPACE_VERSION
81
82  template<class _Tp>
83    class tuple_size;
84
85  template<std::size_t _Int, class _Tp>
86    class tuple_element;
87
88   // Various functions which give std::pair a tuple-like interface.
89  template<class _Tp1, class _Tp2>
90    struct tuple_size<std::pair<_Tp1, _Tp2>>
91    : public integral_constant<std::size_t, 2> { };
92
93  template<class _Tp1, class _Tp2>
94    struct tuple_element<0, std::pair<_Tp1, _Tp2>>
95    { typedef _Tp1 type; };
96
97  template<class _Tp1, class _Tp2>
98    struct tuple_element<1, std::pair<_Tp1, _Tp2>>
99    { typedef _Tp2 type; };
100
101  template<std::size_t _Int>
102    struct __pair_get;
103
104  template<>
105    struct __pair_get<0>
106    {
107      template<typename _Tp1, typename _Tp2>
108        static constexpr _Tp1&
109        __get(std::pair<_Tp1, _Tp2>& __pair) noexcept
110        { return __pair.first; }
111
112      template<typename _Tp1, typename _Tp2>
113        static constexpr _Tp1&&
114        __move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept
115        { return std::forward<_Tp1>(__pair.first); }
116
117      template<typename _Tp1, typename _Tp2>
118        static constexpr const _Tp1&
119        __const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept
120        { return __pair.first; }
121    };
122
123  template<>
124    struct __pair_get<1>
125    {
126      template<typename _Tp1, typename _Tp2>
127        static constexpr _Tp2&
128        __get(std::pair<_Tp1, _Tp2>& __pair) noexcept
129        { return __pair.second; }
130
131      template<typename _Tp1, typename _Tp2>
132        static constexpr _Tp2&&
133        __move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept
134        { return std::forward<_Tp2>(__pair.second); }
135
136      template<typename _Tp1, typename _Tp2>
137        static constexpr const _Tp2&
138        __const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept
139        { return __pair.second; }
140    };
141
142  template<std::size_t _Int, class _Tp1, class _Tp2>
143    constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&
144    get(std::pair<_Tp1, _Tp2>& __in) noexcept
145    { return __pair_get<_Int>::__get(__in); }
146
147  template<std::size_t _Int, class _Tp1, class _Tp2>
148    constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&&
149    get(std::pair<_Tp1, _Tp2>&& __in) noexcept
150    { return __pair_get<_Int>::__move_get(std::move(__in)); }
151
152  template<std::size_t _Int, class _Tp1, class _Tp2>
153    constexpr const typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&
154    get(const std::pair<_Tp1, _Tp2>& __in) noexcept
155    { return __pair_get<_Int>::__const_get(__in); }
156
157_GLIBCXX_END_NAMESPACE_VERSION
158} // namespace
159
160#endif
161
162#endif /* _GLIBCXX_UTILITY */
163