libstdc++
tr1_impl/utility
Go to the documentation of this file.
1 // TR1 utility -*- C++ -*-
2 
3 // Copyright (C) 2007, 2008, 2009 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_impl/utility
26  * This is an internal header file, included by other library headers.
27  * You should not attempt to use it directly.
28  */
29 
30 namespace std
31 {
32 _GLIBCXX_BEGIN_NAMESPACE_TR1
33 
34  template<class _Tp>
35  class tuple_size;
36 
37 #ifdef _GLIBCXX_INCLUDE_AS_CXX0X
38  template<std::size_t _Int, class _Tp>
39 #else
40  template<int _Int, class _Tp>
41 #endif
42  class tuple_element;
43 
44  // Various functions which give std::pair a tuple-like interface.
45  template<class _Tp1, class _Tp2>
46  struct tuple_size<std::pair<_Tp1, _Tp2> >
47 #ifdef _GLIBCXX_INCLUDE_AS_CXX0X
48  { static const std::size_t value = 2; };
49 #else
50  { static const int value = 2; };
51 #endif
52 
53  template<class _Tp1, class _Tp2>
54 #ifdef _GLIBCXX_INCLUDE_AS_CXX0X
55  const std::size_t
56 #else
57  const int
58 #endif
59  tuple_size<std::pair<_Tp1, _Tp2> >::value;
60 
61  template<class _Tp1, class _Tp2>
62  struct tuple_element<0, std::pair<_Tp1, _Tp2> >
63  { typedef _Tp1 type; };
64 
65  template<class _Tp1, class _Tp2>
66  struct tuple_element<1, std::pair<_Tp1, _Tp2> >
67  { typedef _Tp2 type; };
68 
69 #ifdef _GLIBCXX_INCLUDE_AS_CXX0X
70  template<std::size_t _Int>
71 #else
72  template<int _Int>
73 #endif
74  struct __pair_get;
75 
76  template<>
77  struct __pair_get<0>
78  {
79  template<typename _Tp1, typename _Tp2>
80  static _Tp1& __get(std::pair<_Tp1, _Tp2>& __pair)
81  { return __pair.first; }
82 
83  template<typename _Tp1, typename _Tp2>
84  static const _Tp1& __const_get(const std::pair<_Tp1, _Tp2>& __pair)
85  { return __pair.first; }
86  };
87 
88  template<>
89  struct __pair_get<1>
90  {
91  template<typename _Tp1, typename _Tp2>
92  static _Tp2& __get(std::pair<_Tp1, _Tp2>& __pair)
93  { return __pair.second; }
94 
95  template<typename _Tp1, typename _Tp2>
96  static const _Tp2& __const_get(const std::pair<_Tp1, _Tp2>& __pair)
97  { return __pair.second; }
98  };
99 
100 #ifdef _GLIBCXX_INCLUDE_AS_CXX0X
101  template<std::size_t _Int, class _Tp1, class _Tp2>
102 #else
103  template<int _Int, class _Tp1, class _Tp2>
104 #endif
105  inline typename tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type&
106  get(std::pair<_Tp1, _Tp2>& __in)
107  { return __pair_get<_Int>::__get(__in); }
108 
109 #ifdef _GLIBCXX_INCLUDE_AS_CXX0X
110  template<std::size_t _Int, class _Tp1, class _Tp2>
111 #else
112  template<int _Int, class _Tp1, class _Tp2>
113 #endif
114  inline const typename tuple_element<_Int, std::pair<_Tp1, _Tp2> >::type&
115  get(const std::pair<_Tp1, _Tp2>& __in)
116  { return __pair_get<_Int>::__const_get(__in); }
117 
118 _GLIBCXX_END_NAMESPACE_TR1
119 }
120 
pair holds two objects of arbitrary type.
Definition: stl_pair.h:67
_T2 second
second is a copy of the second object
Definition: stl_pair.h:73
_T1 first
first is a copy of the first object
Definition: stl_pair.h:72