libstdc++
typeindex
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1 // C++11 <typeindex> -*- C++ -*-
2 
3 // Copyright (C) 2010-2017 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 include/typeindex
26  * This is a Standard C++ Library header.
27  */
28 
29 #ifndef _GLIBCXX_TYPEINDEX
30 #define _GLIBCXX_TYPEINDEX 1
31 
32 #pragma GCC system_header
33 
34 #if __cplusplus < 201103L
35 # include <bits/c++0x_warning.h>
36 #else
37 
38 #include <typeinfo>
39 
40 namespace std _GLIBCXX_VISIBILITY(default)
41 {
42 _GLIBCXX_BEGIN_NAMESPACE_VERSION
43 
44  /**
45  * @brief Class type_index
46  * @ingroup utilities
47  *
48  * The class type_index provides a simple wrapper for type_info
49  * which can be used as an index type in associative containers
50  * (23.6) and in unordered associative containers (23.7).
51  */
52  struct type_index
53  {
54  type_index(const type_info& __rhs) noexcept
55  : _M_target(&__rhs) { }
56 
57  bool
58  operator==(const type_index& __rhs) const noexcept
59  { return *_M_target == *__rhs._M_target; }
60 
61  bool
62  operator!=(const type_index& __rhs) const noexcept
63  { return *_M_target != *__rhs._M_target; }
64 
65  bool
66  operator<(const type_index& __rhs) const noexcept
67  { return _M_target->before(*__rhs._M_target); }
68 
69  bool
70  operator<=(const type_index& __rhs) const noexcept
71  { return !__rhs._M_target->before(*_M_target); }
72 
73  bool
74  operator>(const type_index& __rhs) const noexcept
75  { return __rhs._M_target->before(*_M_target); }
76 
77  bool
78  operator>=(const type_index& __rhs) const noexcept
79  { return !_M_target->before(*__rhs._M_target); }
80 
81  size_t
82  hash_code() const noexcept
83  { return _M_target->hash_code(); }
84 
85  const char*
86  name() const noexcept
87  { return _M_target->name(); }
88 
89  private:
90  const type_info* _M_target;
91  };
92 
93  template<typename _Tp> struct hash;
94 
95  /// std::hash specialization for type_index.
96  template<>
97  struct hash<type_index>
98  {
99  typedef size_t result_type;
100  typedef type_index argument_type;
101 
102  size_t
103  operator()(const type_index& __ti) const noexcept
104  { return __ti.hash_code(); }
105  };
106 
107 _GLIBCXX_END_NAMESPACE_VERSION
108 } // namespace std
109 
110 #endif // C++11
111 
112 #endif // _GLIBCXX_TYPEINDEX