libstdc++
type_utils.hpp
Go to the documentation of this file.
1// -*- C++ -*-
2
3// Copyright (C) 2005-2021 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 terms
7// of the GNU General Public License as published by the Free Software
8// Foundation; either version 3, or (at your option) any later
9// version.
10
11// This library is distributed in the hope that it will be useful, but
12// WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14// 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// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
26
27// Permission to use, copy, modify, sell, and distribute this software
28// is hereby granted without fee, provided that the above copyright
29// notice appears in all copies, and that both that copyright notice
30// and this permission notice appear in supporting documentation. None
31// of the above authors, nor IBM Haifa Research Laboratories, make any
32// representation about the suitability of this software for any
33// purpose. It is provided "as is" without express or implied
34// warranty.
35
36/**
37 * @file detail/type_utils.hpp
38 * Contains utilities for handling types. All of these classes are based on
39 * Modern C++ by Andrei Alxandrescu.
40 */
41
42#ifndef PB_DS_TYPE_UTILS_HPP
43#define PB_DS_TYPE_UTILS_HPP
44
45#include <cstddef>
46#include <utility>
47#include <tr1/type_traits>
48#include <ext/type_traits.h>
49#include <ext/numeric_traits.h>
50
51namespace __gnu_pbds
52{
53 namespace detail
54 {
55 using std::tr1::is_same;
56 using std::tr1::is_const;
57 using std::tr1::is_pointer;
58 using std::tr1::is_reference;
59 using std::tr1::is_fundamental;
60 using std::tr1::is_member_object_pointer;
61 using std::tr1::is_member_pointer;
62 using std::tr1::is_base_of;
63 using std::tr1::remove_const;
64 using std::tr1::remove_reference;
65
66 // Need integral_const<bool, true> <-> integral_const<int, 1>, so
67 // because of this use the following typedefs instead of importing
68 // std::tr1's.
69 using std::tr1::integral_constant;
70 typedef std::tr1::integral_constant<int, 1> true_type;
71 typedef std::tr1::integral_constant<int, 0> false_type;
72
73 using __gnu_cxx::__conditional_type;
74 using __gnu_cxx::__numeric_traits;
75
76 template<typename T>
77 struct is_const_pointer
78 {
79 enum
80 {
81 value = is_const<T>::value && is_pointer<T>::value
82 };
83 };
84
85 template<typename T>
86 struct is_const_reference
87 {
88 enum
89 {
90 value = is_const<T>::value && is_reference<T>::value
91 };
92 };
93
94 template<typename T>
95 struct is_simple
96 {
97 enum
98 {
99 value = is_fundamental<typename remove_const<T>::type>::value
100 || is_pointer<typename remove_const<T>::type>::value
101 || is_member_pointer<T>::value
102 };
103 };
104
105 template<typename T>
106 class is_pair
107 {
108 private:
109 template<typename U>
110 struct is_pair_imp
111 {
112 enum
113 {
114 value = 0
115 };
116 };
117
118 template<typename U, typename V>
119 struct is_pair_imp<std::pair<U,V> >
120 {
121 enum
122 {
123 value = 1
124 };
125 };
126
127 public:
128 enum
129 {
130 value = is_pair_imp<T>::value
131 };
132 };
133
134 // Use C++11's static_assert if possible.
135#if __cplusplus >= 201103L
136#define PB_DS_STATIC_ASSERT(UNIQUE, E) static_assert(E, #UNIQUE)
137#else
138 template<bool>
139 struct __static_assert;
140
141 template<>
142 struct __static_assert<true>
143 { };
144
145 template<int>
146 struct __static_assert_dumclass
147 {
148 enum
149 {
150 v = 1
151 };
152 };
153
154#define PB_DS_STATIC_ASSERT(UNIQUE, E) \
155 typedef __gnu_pbds::detail::__static_assert_dumclass<sizeof(__gnu_pbds::detail::__static_assert<bool(E)>)> UNIQUE##__static_assert_type
156
157#endif
158
159 template<typename Type>
160 struct type_to_type
161 {
162 typedef Type type;
163 };
164 } // namespace detail
165} // namespace __gnu_pbds
166
167#endif
integral_constant< bool, true > true_type
The type used as a compile-time boolean with true value.
Definition: type_traits:83
integral_constant< bool, false > false_type
The type used as a compile-time boolean with false value.
Definition: type_traits:86
ISO C++ entities toplevel namespace is std.
GNU extensions for policy-based data structures for public use.