libstdc++-v3/include/tr1/utility

   1 // TR1 utility -*- C++ -*-
   2
   3 // Copyright (C) 2004-2021 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 /** @file tr1/utility
  26  *  This is a TR1 C++ Library header.
  27  */
  28
  29 #ifndef _GLIBCXX_TR1_UTILITY
  30 #define _GLIBCXX_TR1_UTILITY 1
  31
  32 #pragma GCC system_header
  33
  34 #include <bits/c++config.h>
  35 #include <bits/stl_relops.h>
  36 #include <bits/stl_pair.h>
  37
  38 namespace std _GLIBCXX_VISIBILITY(default)
  39 {
  40 _GLIBCXX_BEGIN_NAMESPACE_VERSION
  41
  42 namespace tr1
  43 {
  44   template<class _Tp>
  45     class tuple_size;
  46
  47   template<int _Int, class _Tp>
  48     class tuple_element;
  49
  50    // Various functions which give std::pair a tuple-like interface.
  51   template<class _Tp1, class _Tp2>
  52     struct tuple_size<std::pair<_Tp1, _Tp2> >
  53     { static const int value = 2; };
  54
  55   template<class _Tp1, class _Tp2>
  56     const int
  57     tuple_size<std::pair<_Tp1, _Tp2> >::value;
  58
  59   template<class _Tp1, class _Tp2>
  60     struct tuple_element<0, std::pair<_Tp1, _Tp2> >
  61     { typedef _Tp1 type; };
  62
  63   template<class _Tp1, class _Tp2>
  64     struct tuple_element<1, std::pair<_Tp1, _Tp2> >
  65     { typedef _Tp2 type; };
  66
  67   template<int _Int>
  68     struct __pair_get;
  69
  70   template<>
  71     struct __pair_get<0>
  72     {
  73       template<typename _Tp1, typename _Tp2>
  74       static _Tp1& __get(std::pair<_Tp1, _Tp2>& __pair)
  75       { return __pair.first; }
  76
  77       template<typename _Tp1, typename _Tp2>
  78       static const _Tp1& __const_get(const std::pair<_Tp1, _Tp2>& __pair)
  79       { return __pair.first; }
  80     };
  81
  82   template<>
  83     struct __pair_get<1>
  84     {
  85       template<typename _Tp1, typename _Tp2>
  86       static _Tp2& __get(std::pair<_Tp1, _Tp2>& __pair)
  87       { return __pair.second; }
  88
  89       template<typename _Tp1, typename _Tp2>
  90       static const _Tp2& __const_get(const std::pair<_Tp1, _Tp2>& __pair)
  91       { return __pair.second; }
  92     };
  93
  94   template<int _Int, class _Tp1, class _Tp2>
  95     inline typename tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type&
  96     get(std::pair<_Tp1, _Tp2>& __in)
  97     { return __pair_get<_Int>::__get(__in); }
  98
  99   template<int _Int, class _Tp1, class _Tp2>
 100     inline const typename tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type&
 101     get(const std::pair<_Tp1, _Tp2>& __in)
 102     { return __pair_get<_Int>::__const_get(__in); }
 103 }
 104
 105 _GLIBCXX_END_NAMESPACE_VERSION
 106 }
 107
 108 #endif // _GLIBCXX_TR1_UTILITY