1// TR1 utility -*- C++ -*- 2 3// Copyright (C) 2004, 2005 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 2, 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// You should have received a copy of the GNU General Public License along 17// with this library; see the file COPYING. If not, write to the Free 18// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 19// USA. 20 21// As a special exception, you may use this file as part of a free software 22// library without restriction. Specifically, if other files instantiate 23// templates or use macros or inline functions from this file, or you compile 24// this file and link it with other files to produce an executable, this 25// file does not by itself cause the resulting executable to be covered by 26// the GNU General Public License. This exception does not however 27// invalidate any other reasons why the executable file might be covered by 28// the GNU General Public License. 29 30/** @file 31 * This is a TR1 C++ Library header. 32 */ 33 34#ifndef _TR1_UTILITY 35#define _TR1_UTILITY 1 36 37#include "../utility" 38 39namespace std 40{ 41namespace tr1 42{ 43 template<class _Tp> class tuple_size; 44 template<int _Int, class _Tp> class tuple_element; 45 46 // Various functions which give std::pair a tuple-like interface. 47 template<class _Tp1, class _Tp2> 48 struct tuple_size<std::pair<_Tp1, _Tp2> > 49 { static const int value = 2; }; 50 51 template<class _Tp1, class _Tp2> 52 struct tuple_element<0, std::pair<_Tp1, _Tp2> > 53 { typedef _Tp1 type; }; 54 55 template<class _Tp1, class _Tp2> 56 struct tuple_element<1, std::pair<_Tp1, _Tp2> > 57 { typedef _Tp2 type; }; 58 59 60 template<int _Int> struct __pair_get; 61 62 template<> 63 struct __pair_get<0> 64 { 65 template<typename _Tp1, typename _Tp2> 66 static _Tp1& __get(std::pair<_Tp1, _Tp2>& __pair) 67 { return __pair.first; } 68 69 template<typename _Tp1, typename _Tp2> 70 static const _Tp1& __const_get(const std::pair<_Tp1, _Tp2>& __pair) 71 { return __pair.first; } 72 }; 73 74 template<> 75 struct __pair_get<1> 76 { 77 template<typename _Tp1, typename _Tp2> 78 static _Tp2& __get(std::pair<_Tp1, _Tp2>& __pair) 79 { return __pair.second; } 80 81 template<typename _Tp1, typename _Tp2> 82 static const _Tp2& __const_get(const std::pair<_Tp1, _Tp2>& __pair) 83 { return __pair.second; } 84 }; 85 86 template<int _Int, class _Tp1, class _Tp2> 87 typename tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type& 88 get(pair<_Tp1, _Tp2>& __in) 89 { return __pair_get<_Int>::__get(__in); } 90 91 template<int _Int, class _Tp1, class _Tp2> 92 const typename tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type& 93 get(const pair<_Tp1, _Tp2>& __in) 94 { return __pair_get<_Int>::__const_get(__in); } 95} 96} 97 98#endif 99