libstdc++
utility
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00001 // <utility> -*- C++ -*-
00002 
00003 // Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
00004 // 2010, 2011
00005 // Free Software Foundation, Inc.
00006 //
00007 // This file is part of the GNU ISO C++ Library.  This library is free
00008 // software; you can redistribute it and/or modify it under the
00009 // terms of the GNU General Public License as published by the
00010 // Free Software Foundation; either version 3, or (at your option)
00011 // any later version.
00012 
00013 // This library is distributed in the hope that it will be useful,
00014 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00015 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00016 // GNU General Public License for more details.
00017 
00018 // Under Section 7 of GPL version 3, you are granted additional
00019 // permissions described in the GCC Runtime Library Exception, version
00020 // 3.1, as published by the Free Software Foundation.
00021 
00022 // You should have received a copy of the GNU General Public License and
00023 // a copy of the GCC Runtime Library Exception along with this program;
00024 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00025 // <http://www.gnu.org/licenses/>.
00026 
00027 /*
00028  *
00029  * Copyright (c) 1994
00030  * Hewlett-Packard Company
00031  *
00032  * Permission to use, copy, modify, distribute and sell this software
00033  * and its documentation for any purpose is hereby granted without fee,
00034  * provided that the above copyright notice appear in all copies and
00035  * that both that copyright notice and this permission notice appear
00036  * in supporting documentation.  Hewlett-Packard Company makes no
00037  * representations about the suitability of this software for any
00038  * purpose.  It is provided "as is" without express or implied warranty.
00039  *
00040  *
00041  * Copyright (c) 1996,1997
00042  * Silicon Graphics Computer Systems, Inc.
00043  *
00044  * Permission to use, copy, modify, distribute and sell this software
00045  * and its documentation for any purpose is hereby granted without fee,
00046  * provided that the above copyright notice appear in all copies and
00047  * that both that copyright notice and this permission notice appear
00048  * in supporting documentation.  Silicon Graphics makes no
00049  * representations about the suitability of this software for any
00050  * purpose.  It is provided "as is" without express or implied warranty.
00051  */
00052 
00053 /** @file include/utility
00054  *  This is a Standard C++ Library header. 
00055  */
00056 
00057 #ifndef _GLIBCXX_UTILITY
00058 #define _GLIBCXX_UTILITY 1
00059 
00060 #pragma GCC system_header
00061 
00062 /**
00063  * @defgroup utilities Utilities
00064  *
00065  * Components deemed generally useful. Includes pair, tuple,
00066  * forward/move helpers, ratio, function object, metaprogramming and
00067  * type traits, time, date, and memory functions.
00068  */
00069 
00070 #include <bits/c++config.h>
00071 #include <bits/stl_relops.h>
00072 #include <bits/stl_pair.h>
00073 
00074 #ifdef __GXX_EXPERIMENTAL_CXX0X__
00075 #include <bits/move.h>
00076 #include <initializer_list>
00077 
00078 namespace std _GLIBCXX_VISIBILITY(default)
00079 {
00080 _GLIBCXX_BEGIN_NAMESPACE_VERSION
00081 
00082   template<class _Tp>
00083     class tuple_size;
00084 
00085   template<std::size_t _Int, class _Tp>
00086     class tuple_element;
00087 
00088    // Various functions which give std::pair a tuple-like interface.
00089   template<class _Tp1, class _Tp2>
00090     struct tuple_size<std::pair<_Tp1, _Tp2>>
00091     : public integral_constant<std::size_t, 2> { };
00092 
00093   template<class _Tp1, class _Tp2>
00094     struct tuple_element<0, std::pair<_Tp1, _Tp2>>
00095     { typedef _Tp1 type; };
00096  
00097   template<class _Tp1, class _Tp2>
00098     struct tuple_element<1, std::pair<_Tp1, _Tp2>>
00099     { typedef _Tp2 type; };
00100 
00101   template<std::size_t _Int>
00102     struct __pair_get;
00103 
00104   template<>
00105     struct __pair_get<0>
00106     {
00107       template<typename _Tp1, typename _Tp2>
00108         static constexpr _Tp1&
00109         __get(std::pair<_Tp1, _Tp2>& __pair) noexcept
00110         { return __pair.first; }
00111 
00112       template<typename _Tp1, typename _Tp2>
00113         static constexpr _Tp1&&
00114         __move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept
00115         { return std::forward<_Tp1>(__pair.first); }
00116 
00117       template<typename _Tp1, typename _Tp2>
00118         static constexpr const _Tp1&
00119         __const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept
00120         { return __pair.first; }
00121     };
00122 
00123   template<>
00124     struct __pair_get<1>
00125     {
00126       template<typename _Tp1, typename _Tp2>
00127         static constexpr _Tp2&
00128         __get(std::pair<_Tp1, _Tp2>& __pair) noexcept
00129         { return __pair.second; }
00130 
00131       template<typename _Tp1, typename _Tp2>
00132         static constexpr _Tp2&&
00133         __move_get(std::pair<_Tp1, _Tp2>&& __pair) noexcept
00134         { return std::forward<_Tp2>(__pair.second); }
00135 
00136       template<typename _Tp1, typename _Tp2>
00137         static constexpr const _Tp2&
00138         __const_get(const std::pair<_Tp1, _Tp2>& __pair) noexcept
00139         { return __pair.second; }
00140     };
00141 
00142   template<std::size_t _Int, class _Tp1, class _Tp2>
00143     constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&
00144     get(std::pair<_Tp1, _Tp2>& __in) noexcept
00145     { return __pair_get<_Int>::__get(__in); }
00146 
00147   template<std::size_t _Int, class _Tp1, class _Tp2>
00148     constexpr typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&&
00149     get(std::pair<_Tp1, _Tp2>&& __in) noexcept
00150     { return __pair_get<_Int>::__move_get(std::move(__in)); }
00151 
00152   template<std::size_t _Int, class _Tp1, class _Tp2>
00153     constexpr const typename tuple_element<_Int, std::pair<_Tp1, _Tp2>>::type&
00154     get(const std::pair<_Tp1, _Tp2>& __in) noexcept
00155     { return __pair_get<_Int>::__const_get(__in); }
00156 
00157 _GLIBCXX_END_NAMESPACE_VERSION
00158 } // namespace
00159 
00160 #endif
00161 
00162 #endif /* _GLIBCXX_UTILITY */