1 // <bits/enable_special_members.h> -*- C++ -*-
2
3 // Copyright (C) 2013-2015 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 bits/enable_special_members.h
26 * This is an internal header file, included by other library headers.
27 * Do not attempt to use it directly.
28 */
29
30 #ifndef _ENABLE_SPECIAL_MEMBERS_H
31 #define _ENABLE_SPECIAL_MEMBERS_H 1
32
33 #pragma GCC system_header
34
_GLIBCXX_VISIBILITY(default)35 namespace std _GLIBCXX_VISIBILITY(default)
36 {
37 _GLIBCXX_BEGIN_NAMESPACE_VERSION
38
39 /**
40 * @brief A mixin helper to conditionally enable or disable the default
41 * constructor.
42 * @sa _Enable_special_members
43 */
44 template<bool _Switch, typename _Tag = void>
45 struct _Enable_default_constructor { };
46
47
48 /**
49 * @brief A mixin helper to conditionally enable or disable the default
50 * destructor.
51 * @sa _Enable_special_members
52 */
53 template<bool _Switch, typename _Tag = void>
54 struct _Enable_destructor { };
55
56 /**
57 * @brief A mixin helper to conditionally enable or disable the copy/move
58 * special members.
59 * @sa _Enable_special_members
60 */
61 template<bool _Copy, bool _CopyAssignment,
62 bool _Move, bool _MoveAssignment,
63 typename _Tag = void>
64 struct _Enable_copy_move { };
65
66 /**
67 * @brief A mixin helper to conditionally enable or disable the special
68 * members.
69 *
70 * The @c _Tag type parameter is to make mixin bases unique and thus avoid
71 * ambiguities.
72 */
73 template<bool _Default, bool _Destructor,
74 bool _Copy, bool _CopyAssignment,
75 bool _Move, bool _MoveAssignment,
76 typename _Tag = void>
77 struct _Enable_special_members
78 : private _Enable_default_constructor<_Default, _Tag>,
79 private _Enable_destructor<_Destructor, _Tag>,
80 private _Enable_copy_move<_Copy, _CopyAssignment,
81 _Move, _MoveAssignment,
82 _Tag>
83 { };
84
85 // Boilerplate follows.
86
87 template<typename _Tag>
88 struct _Enable_default_constructor<false, _Tag>
89 { constexpr _Enable_default_constructor() noexcept = delete; };
90
91 template<typename _Tag>
92 struct _Enable_destructor<false, _Tag>
93 { ~_Enable_destructor() noexcept = delete; };
94
95 template<typename _Tag>
96 struct _Enable_copy_move<false, true, true, true, _Tag>
97 {
98 constexpr _Enable_copy_move() noexcept = default;
99 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
100 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
101 _Enable_copy_move&
102 operator=(_Enable_copy_move const&) noexcept = default;
103 _Enable_copy_move&
104 operator=(_Enable_copy_move&&) noexcept = default;
105 };
106
107 template<typename _Tag>
108 struct _Enable_copy_move<true, false, true, true, _Tag>
109 {
110 constexpr _Enable_copy_move() noexcept = default;
111 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
112 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
113 _Enable_copy_move&
114 operator=(_Enable_copy_move const&) noexcept = delete;
115 _Enable_copy_move&
116 operator=(_Enable_copy_move&&) noexcept = default;
117 };
118
119 template<typename _Tag>
120 struct _Enable_copy_move<false, false, true, true, _Tag>
121 {
122 constexpr _Enable_copy_move() noexcept = default;
123 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
124 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
125 _Enable_copy_move&
126 operator=(_Enable_copy_move const&) noexcept = delete;
127 _Enable_copy_move&
128 operator=(_Enable_copy_move&&) noexcept = default;
129 };
130
131 template<typename _Tag>
132 struct _Enable_copy_move<true, true, false, true, _Tag>
133 {
134 constexpr _Enable_copy_move() noexcept = default;
135 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
136 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
137 _Enable_copy_move&
138 operator=(_Enable_copy_move const&) noexcept = default;
139 _Enable_copy_move&
140 operator=(_Enable_copy_move&&) noexcept = default;
141 };
142
143 template<typename _Tag>
144 struct _Enable_copy_move<false, true, false, true, _Tag>
145 {
146 constexpr _Enable_copy_move() noexcept = default;
147 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
148 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
149 _Enable_copy_move&
150 operator=(_Enable_copy_move const&) noexcept = default;
151 _Enable_copy_move&
152 operator=(_Enable_copy_move&&) noexcept = default;
153 };
154
155 template<typename _Tag>
156 struct _Enable_copy_move<true, false, false, true, _Tag>
157 {
158 constexpr _Enable_copy_move() noexcept = default;
159 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
160 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
161 _Enable_copy_move&
162 operator=(_Enable_copy_move const&) noexcept = delete;
163 _Enable_copy_move&
164 operator=(_Enable_copy_move&&) noexcept = default;
165 };
166
167 template<typename _Tag>
168 struct _Enable_copy_move<false, false, false, true, _Tag>
169 {
170 constexpr _Enable_copy_move() noexcept = default;
171 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
172 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
173 _Enable_copy_move&
174 operator=(_Enable_copy_move const&) noexcept = delete;
175 _Enable_copy_move&
176 operator=(_Enable_copy_move&&) noexcept = default;
177 };
178
179 template<typename _Tag>
180 struct _Enable_copy_move<true, true, true, false, _Tag>
181 {
182 constexpr _Enable_copy_move() noexcept = default;
183 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
184 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
185 _Enable_copy_move&
186 operator=(_Enable_copy_move const&) noexcept = default;
187 _Enable_copy_move&
188 operator=(_Enable_copy_move&&) noexcept = delete;
189 };
190
191 template<typename _Tag>
192 struct _Enable_copy_move<false, true, true, false, _Tag>
193 {
194 constexpr _Enable_copy_move() noexcept = default;
195 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
196 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
197 _Enable_copy_move&
198 operator=(_Enable_copy_move const&) noexcept = default;
199 _Enable_copy_move&
200 operator=(_Enable_copy_move&&) noexcept = delete;
201 };
202
203 template<typename _Tag>
204 struct _Enable_copy_move<true, false, true, false, _Tag>
205 {
206 constexpr _Enable_copy_move() noexcept = default;
207 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
208 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
209 _Enable_copy_move&
210 operator=(_Enable_copy_move const&) noexcept = delete;
211 _Enable_copy_move&
212 operator=(_Enable_copy_move&&) noexcept = delete;
213 };
214
215 template<typename _Tag>
216 struct _Enable_copy_move<false, false, true, false, _Tag>
217 {
218 constexpr _Enable_copy_move() noexcept = default;
219 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
220 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = default;
221 _Enable_copy_move&
222 operator=(_Enable_copy_move const&) noexcept = delete;
223 _Enable_copy_move&
224 operator=(_Enable_copy_move&&) noexcept = delete;
225 };
226
227 template<typename _Tag>
228 struct _Enable_copy_move<true, true, false, false, _Tag>
229 {
230 constexpr _Enable_copy_move() noexcept = default;
231 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
232 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
233 _Enable_copy_move&
234 operator=(_Enable_copy_move const&) noexcept = default;
235 _Enable_copy_move&
236 operator=(_Enable_copy_move&&) noexcept = delete;
237 };
238
239 template<typename _Tag>
240 struct _Enable_copy_move<false, true, false, false, _Tag>
241 {
242 constexpr _Enable_copy_move() noexcept = default;
243 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
244 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
245 _Enable_copy_move&
246 operator=(_Enable_copy_move const&) noexcept = default;
247 _Enable_copy_move&
248 operator=(_Enable_copy_move&&) noexcept = delete;
249 };
250
251 template<typename _Tag>
252 struct _Enable_copy_move<true, false, false, false, _Tag>
253 {
254 constexpr _Enable_copy_move() noexcept = default;
255 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = default;
256 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
257 _Enable_copy_move&
258 operator=(_Enable_copy_move const&) noexcept = delete;
259 _Enable_copy_move&
260 operator=(_Enable_copy_move&&) noexcept = delete;
261 };
262
263 template<typename _Tag>
264 struct _Enable_copy_move<false, false, false, false, _Tag>
265 {
266 constexpr _Enable_copy_move() noexcept = default;
267 constexpr _Enable_copy_move(_Enable_copy_move const&) noexcept = delete;
268 constexpr _Enable_copy_move(_Enable_copy_move&&) noexcept = delete;
269 _Enable_copy_move&
270 operator=(_Enable_copy_move const&) noexcept = delete;
271 _Enable_copy_move&
272 operator=(_Enable_copy_move&&) noexcept = delete;
273 };
274
275 _GLIBCXX_END_NAMESPACE_VERSION
276 } // namespace std
277
278 #endif // _ENABLE_SPECIAL_MEMBERS_H
279