1// <tuple> -*- C++ -*-
2
3// Copyright (C) 2007-2016 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/tuple
26 * This is a Standard C++ Library header.
27 */
28
29#ifndef _GLIBCXX_TUPLE
30#define _GLIBCXX_TUPLE 1
31
32#pragma GCC system_header
33
34#if __cplusplus < 201103L
35# include <bits/c++0x_warning.h>
36#else
37
38#include <utility>
39#include <array>
40#include <bits/uses_allocator.h>
41
42namespace std _GLIBCXX_VISIBILITY(default)
43{
44_GLIBCXX_BEGIN_NAMESPACE_VERSION
45
46 /**
47 * @addtogroup utilities
48 * @{
49 */
50
51 template<std::size_t _Idx, typename _Head, bool _IsEmptyNotFinal>
52 struct _Head_base;
53
54 template<std::size_t _Idx, typename _Head>
55 struct _Head_base<_Idx, _Head, true>
56 : public _Head
57 {
58 constexpr _Head_base()
59 : _Head() { }
60
61 constexpr _Head_base(const _Head& __h)
62 : _Head(__h) { }
63
64 constexpr _Head_base(const _Head_base&) = default;
65 constexpr _Head_base(_Head_base&&) = default;
66
67 template<typename _UHead>
68 constexpr _Head_base(_UHead&& __h)
69 : _Head(std::forward<_UHead>(__h)) { }
70
71 _Head_base(allocator_arg_t, __uses_alloc0)
72 : _Head() { }
73
74 template<typename _Alloc>
75 _Head_base(allocator_arg_t, __uses_alloc1<_Alloc> __a)
76 : _Head(allocator_arg, *__a._M_a) { }
77
78 template<typename _Alloc>
79 _Head_base(allocator_arg_t, __uses_alloc2<_Alloc> __a)
80 : _Head(*__a._M_a) { }
81
82 template<typename _UHead>
83 _Head_base(__uses_alloc0, _UHead&& __uhead)
84 : _Head(std::forward<_UHead>(__uhead)) { }
85
86 template<typename _Alloc, typename _UHead>
87 _Head_base(__uses_alloc1<_Alloc> __a, _UHead&& __uhead)
88 : _Head(allocator_arg, *__a._M_a, std::forward<_UHead>(__uhead)) { }
89
90 template<typename _Alloc, typename _UHead>
91 _Head_base(__uses_alloc2<_Alloc> __a, _UHead&& __uhead)
92 : _Head(std::forward<_UHead>(__uhead), *__a._M_a) { }
93
94 static constexpr _Head&
95 _M_head(_Head_base& __b) noexcept { return __b; }
96
97 static constexpr const _Head&
98 _M_head(const _Head_base& __b) noexcept { return __b; }
99 };
100
101 template<std::size_t _Idx, typename _Head>
102 struct _Head_base<_Idx, _Head, false>
103 {
104 constexpr _Head_base()
105 : _M_head_impl() { }
106
107 constexpr _Head_base(const _Head& __h)
108 : _M_head_impl(__h) { }
109
110 constexpr _Head_base(const _Head_base&) = default;
111 constexpr _Head_base(_Head_base&&) = default;
112
113 template<typename _UHead>
114 constexpr _Head_base(_UHead&& __h)
115 : _M_head_impl(std::forward<_UHead>(__h)) { }
116
117 _Head_base(allocator_arg_t, __uses_alloc0)
118 : _M_head_impl() { }
119
120 template<typename _Alloc>
121 _Head_base(allocator_arg_t, __uses_alloc1<_Alloc> __a)
122 : _M_head_impl(allocator_arg, *__a._M_a) { }
123
124 template<typename _Alloc>
125 _Head_base(allocator_arg_t, __uses_alloc2<_Alloc> __a)
126 : _M_head_impl(*__a._M_a) { }
127
128 template<typename _UHead>
129 _Head_base(__uses_alloc0, _UHead&& __uhead)
130 : _M_head_impl(std::forward<_UHead>(__uhead)) { }
131
132 template<typename _Alloc, typename _UHead>
133 _Head_base(__uses_alloc1<_Alloc> __a, _UHead&& __uhead)
134 : _M_head_impl(allocator_arg, *__a._M_a, std::forward<_UHead>(__uhead))
135 { }
136
137 template<typename _Alloc, typename _UHead>
138 _Head_base(__uses_alloc2<_Alloc> __a, _UHead&& __uhead)
139 : _M_head_impl(std::forward<_UHead>(__uhead), *__a._M_a) { }
140
141 static constexpr _Head&
142 _M_head(_Head_base& __b) noexcept { return __b._M_head_impl; }
143
144 static constexpr const _Head&
145 _M_head(const _Head_base& __b) noexcept { return __b._M_head_impl; }
146
147 _Head _M_head_impl;
148 };
149
150 /**
151 * Contains the actual implementation of the @c tuple template, stored
152 * as a recursive inheritance hierarchy from the first element (most
153 * derived class) to the last (least derived class). The @c Idx
154 * parameter gives the 0-based index of the element stored at this
155 * point in the hierarchy; we use it to implement a constant-time
156 * get() operation.
157 */
158 template<std::size_t _Idx, typename... _Elements>
159 struct _Tuple_impl;
160
161 template<typename _Tp>
162 struct __is_empty_non_tuple : is_empty<_Tp> { };
163
164 // Using EBO for elements that are tuples causes ambiguous base errors.
165 template<typename _El0, typename... _El>
166 struct __is_empty_non_tuple<tuple<_El0, _El...>> : false_type { };
167
168 // Use the Empty Base-class Optimization for empty, non-final types.
169 template<typename _Tp>
170 using __empty_not_final
171 = typename conditional<__is_final(_Tp), false_type,
172 __is_empty_non_tuple<_Tp>>::type;
173
174 /**
175 * Recursive tuple implementation. Here we store the @c Head element
176 * and derive from a @c Tuple_impl containing the remaining elements
177 * (which contains the @c Tail).
178 */
179 template<std::size_t _Idx, typename _Head, typename... _Tail>
180 struct _Tuple_impl<_Idx, _Head, _Tail...>
181 : public _Tuple_impl<_Idx + 1, _Tail...>,
182 private _Head_base<_Idx, _Head, __empty_not_final<_Head>::value>
183 {
184 template<std::size_t, typename...> friend class _Tuple_impl;
185
186 typedef _Tuple_impl<_Idx + 1, _Tail...> _Inherited;
187 typedef _Head_base<_Idx, _Head, __empty_not_final<_Head>::value> _Base;
188
189 static constexpr _Head&
190 _M_head(_Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
191
192 static constexpr const _Head&
193 _M_head(const _Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
194
195 static constexpr _Inherited&
196 _M_tail(_Tuple_impl& __t) noexcept { return __t; }
197
198 static constexpr const _Inherited&
199 _M_tail(const _Tuple_impl& __t) noexcept { return __t; }
200
201 constexpr _Tuple_impl()
202 : _Inherited(), _Base() { }
203
204 explicit
205 constexpr _Tuple_impl(const _Head& __head, const _Tail&... __tail)
206 : _Inherited(__tail...), _Base(__head) { }
207
208 template<typename _UHead, typename... _UTail, typename = typename
209 enable_if<sizeof...(_Tail) == sizeof...(_UTail)>::type>
210 explicit
211 constexpr _Tuple_impl(_UHead&& __head, _UTail&&... __tail)
212 : _Inherited(std::forward<_UTail>(__tail)...),
213 _Base(std::forward<_UHead>(__head)) { }
214
215 constexpr _Tuple_impl(const _Tuple_impl&) = default;
216
217 constexpr
218 _Tuple_impl(_Tuple_impl&& __in)
219 noexcept(__and_<is_nothrow_move_constructible<_Head>,
220 is_nothrow_move_constructible<_Inherited>>::value)
221 : _Inherited(std::move(_M_tail(__in))),
222 _Base(std::forward<_Head>(_M_head(__in))) { }
223
224 template<typename... _UElements>
225 constexpr _Tuple_impl(const _Tuple_impl<_Idx, _UElements...>& __in)
226 : _Inherited(_Tuple_impl<_Idx, _UElements...>::_M_tail(__in)),
227 _Base(_Tuple_impl<_Idx, _UElements...>::_M_head(__in)) { }
228
229 template<typename _UHead, typename... _UTails>
230 constexpr _Tuple_impl(_Tuple_impl<_Idx, _UHead, _UTails...>&& __in)
231 : _Inherited(std::move
232 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_tail(__in))),
233 _Base(std::forward<_UHead>
234 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_head(__in))) { }
235
236 template<typename _Alloc>
237 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a)
238 : _Inherited(__tag, __a),
239 _Base(__tag, __use_alloc<_Head>(__a)) { }
240
241 template<typename _Alloc>
242 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
243 const _Head& __head, const _Tail&... __tail)
244 : _Inherited(__tag, __a, __tail...),
245 _Base(__use_alloc<_Head, _Alloc, _Head>(__a), __head) { }
246
247 template<typename _Alloc, typename _UHead, typename... _UTail,
248 typename = typename enable_if<sizeof...(_Tail)
249 == sizeof...(_UTail)>::type>
250 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
251 _UHead&& __head, _UTail&&... __tail)
252 : _Inherited(__tag, __a, std::forward<_UTail>(__tail)...),
253 _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
254 std::forward<_UHead>(__head)) { }
255
256 template<typename _Alloc>
257 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
258 const _Tuple_impl& __in)
259 : _Inherited(__tag, __a, _M_tail(__in)),
260 _Base(__use_alloc<_Head, _Alloc, _Head>(__a), _M_head(__in)) { }
261
262 template<typename _Alloc>
263 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
264 _Tuple_impl&& __in)
265 : _Inherited(__tag, __a, std::move(_M_tail(__in))),
266 _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
267 std::forward<_Head>(_M_head(__in))) { }
268
269 template<typename _Alloc, typename... _UElements>
270 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
271 const _Tuple_impl<_Idx, _UElements...>& __in)
272 : _Inherited(__tag, __a,
273 _Tuple_impl<_Idx, _UElements...>::_M_tail(__in)),
274 _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
275 _Tuple_impl<_Idx, _UElements...>::_M_head(__in)) { }
276
277 template<typename _Alloc, typename _UHead, typename... _UTails>
278 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
279 _Tuple_impl<_Idx, _UHead, _UTails...>&& __in)
280 : _Inherited(__tag, __a, std::move
281 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_tail(__in))),
282 _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
283 std::forward<_UHead>
284 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_head(__in))) { }
285
286 _Tuple_impl&
287 operator=(const _Tuple_impl& __in)
288 {
289 _M_head(*this) = _M_head(__in);
290 _M_tail(*this) = _M_tail(__in);
291 return *this;
292 }
293
294 _Tuple_impl&
295 operator=(_Tuple_impl&& __in)
296 noexcept(__and_<is_nothrow_move_assignable<_Head>,
297 is_nothrow_move_assignable<_Inherited>>::value)
298 {
299 _M_head(*this) = std::forward<_Head>(_M_head(__in));
300 _M_tail(*this) = std::move(_M_tail(__in));
301 return *this;
302 }
303
304 template<typename... _UElements>
305 _Tuple_impl&
306 operator=(const _Tuple_impl<_Idx, _UElements...>& __in)
307 {
308 _M_head(*this) = _Tuple_impl<_Idx, _UElements...>::_M_head(__in);
309 _M_tail(*this) = _Tuple_impl<_Idx, _UElements...>::_M_tail(__in);
310 return *this;
311 }
312
313 template<typename _UHead, typename... _UTails>
314 _Tuple_impl&
315 operator=(_Tuple_impl<_Idx, _UHead, _UTails...>&& __in)
316 {
317 _M_head(*this) = std::forward<_UHead>
318 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_head(__in));
319 _M_tail(*this) = std::move
320 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_tail(__in));
321 return *this;
322 }
323
324 protected:
325 void
326 _M_swap(_Tuple_impl& __in)
327 noexcept(__is_nothrow_swappable<_Head>::value
328 && noexcept(_M_tail(__in)._M_swap(_M_tail(__in))))
329 {
330 using std::swap;
331 swap(_M_head(*this), _M_head(__in));
332 _Inherited::_M_swap(_M_tail(__in));
333 }
334 };
335
336 // Basis case of inheritance recursion.
337 template<std::size_t _Idx, typename _Head>
338 struct _Tuple_impl<_Idx, _Head>
339 : private _Head_base<_Idx, _Head, __empty_not_final<_Head>::value>
340 {
341 template<std::size_t, typename...> friend class _Tuple_impl;
342
343 typedef _Head_base<_Idx, _Head, __empty_not_final<_Head>::value> _Base;
344
345 static constexpr _Head&
346 _M_head(_Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
347
348 static constexpr const _Head&
349 _M_head(const _Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
350
351 constexpr _Tuple_impl()
352 : _Base() { }
353
354 explicit
355 constexpr _Tuple_impl(const _Head& __head)
356 : _Base(__head) { }
357
358 template<typename _UHead>
359 explicit
360 constexpr _Tuple_impl(_UHead&& __head)
361 : _Base(std::forward<_UHead>(__head)) { }
362
363 constexpr _Tuple_impl(const _Tuple_impl&) = default;
364
365 constexpr
366 _Tuple_impl(_Tuple_impl&& __in)
367 noexcept(is_nothrow_move_constructible<_Head>::value)
368 : _Base(std::forward<_Head>(_M_head(__in))) { }
369
370 template<typename _UHead>
371 constexpr _Tuple_impl(const _Tuple_impl<_Idx, _UHead>& __in)
372 : _Base(_Tuple_impl<_Idx, _UHead>::_M_head(__in)) { }
373
374 template<typename _UHead>
375 constexpr _Tuple_impl(_Tuple_impl<_Idx, _UHead>&& __in)
376 : _Base(std::forward<_UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in)))
377 { }
378
379 template<typename _Alloc>
380 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a)
381 : _Base(__tag, __use_alloc<_Head>(__a)) { }
382
383 template<typename _Alloc>
384 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
385 const _Head& __head)
386 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a), __head) { }
387
388 template<typename _Alloc, typename _UHead>
389 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
390 _UHead&& __head)
391 : _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
392 std::forward<_UHead>(__head)) { }
393
394 template<typename _Alloc>
395 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
396 const _Tuple_impl& __in)
397 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a), _M_head(__in)) { }
398
399 template<typename _Alloc>
400 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
401 _Tuple_impl&& __in)
402 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
403 std::forward<_Head>(_M_head(__in))) { }
404
405 template<typename _Alloc, typename _UHead>
406 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
407 const _Tuple_impl<_Idx, _UHead>& __in)
408 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
409 _Tuple_impl<_Idx, _UHead>::_M_head(__in)) { }
410
411 template<typename _Alloc, typename _UHead>
412 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
413 _Tuple_impl<_Idx, _UHead>&& __in)
414 : _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
415 std::forward<_UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in)))
416 { }
417
418 _Tuple_impl&
419 operator=(const _Tuple_impl& __in)
420 {
421 _M_head(*this) = _M_head(__in);
422 return *this;
423 }
424
425 _Tuple_impl&
426 operator=(_Tuple_impl&& __in)
427 noexcept(is_nothrow_move_assignable<_Head>::value)
428 {
429 _M_head(*this) = std::forward<_Head>(_M_head(__in));
430 return *this;
431 }
432
433 template<typename _UHead>
434 _Tuple_impl&
435 operator=(const _Tuple_impl<_Idx, _UHead>& __in)
436 {
437 _M_head(*this) = _Tuple_impl<_Idx, _UHead>::_M_head(__in);
438 return *this;
439 }
440
441 template<typename _UHead>
442 _Tuple_impl&
443 operator=(_Tuple_impl<_Idx, _UHead>&& __in)
444 {
445 _M_head(*this)
446 = std::forward<_UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in));
447 return *this;
448 }
449
450 protected:
451 void
452 _M_swap(_Tuple_impl& __in)
453 noexcept(__is_nothrow_swappable<_Head>::value)
454 {
455 using std::swap;
456 swap(_M_head(*this), _M_head(__in));
457 }
458 };
459
460 template<typename... _Elements>
461 class tuple;
462
463 // Concept utility functions, reused in conditionally-explicit
464 // constructors.
465 template<bool, typename... _Elements>
466 struct _TC
467 {
468 template<typename... _UElements>
469 static constexpr bool _ConstructibleTuple()
470 {
471 return __and_<is_constructible<_Elements, const _UElements&>...>::value;
472 }
473
474 template<typename... _UElements>
475 static constexpr bool _ImplicitlyConvertibleTuple()
476 {
477 return __and_<is_convertible<const _UElements&, _Elements>...>::value;
478 }
479
480 template<typename... _UElements>
481 static constexpr bool _MoveConstructibleTuple()
482 {
483 return __and_<is_constructible<_Elements, _UElements&&>...>::value;
484 }
485
486 template<typename... _UElements>
487 static constexpr bool _ImplicitlyMoveConvertibleTuple()
488 {
489 return __and_<is_convertible<_UElements&&, _Elements>...>::value;
490 }
491
492 template<typename _SrcTuple>
493 static constexpr bool _NonNestedTuple()
494 {
495 return __and_<__not_<is_same<tuple<_Elements...>,
496 typename remove_cv<
497 typename remove_reference<_SrcTuple>::type
498 >::type>>,
499 __not_<is_convertible<_SrcTuple, _Elements...>>,
500 __not_<is_constructible<_Elements..., _SrcTuple>>
501 >::value;
502 }
503 template<typename... _UElements>
504 static constexpr bool _NotSameTuple()
505 {
506 return __not_<is_same<tuple<_Elements...>,
507 typename remove_const<
508 typename remove_reference<_UElements...>::type
509 >::type>>::value;
510 }
511 };
512
513 template<typename... _Elements>
514 struct _TC<false, _Elements...>
515 {
516 template<typename... _UElements>
517 static constexpr bool _ConstructibleTuple()
518 {
519 return false;
520 }
521
522 template<typename... _UElements>
523 static constexpr bool _ImplicitlyConvertibleTuple()
524 {
525 return false;
526 }
527
528 template<typename... _UElements>
529 static constexpr bool _MoveConstructibleTuple()
530 {
531 return false;
532 }
533
534 template<typename... _UElements>
535 static constexpr bool _ImplicitlyMoveConvertibleTuple()
536 {
537 return false;
538 }
539
540 template<typename... _UElements>
541 static constexpr bool _NonNestedTuple()
542 {
543 return true;
544 }
545 template<typename... _UElements>
546 static constexpr bool _NotSameTuple()
547 {
548 return true;
549 }
550 };
551
552 /// Primary class template, tuple
553 template<typename... _Elements>
554 class tuple : public _Tuple_impl<0, _Elements...>
555 {
556 typedef _Tuple_impl<0, _Elements...> _Inherited;
557
558 // Used for constraining the default constructor so
559 // that it becomes dependent on the constraints.
560 template<typename _Dummy>
561 struct _TC2
562 {
563 static constexpr bool _DefaultConstructibleTuple()
564 {
565 return __and_<is_default_constructible<_Elements>...>::value;
566 }
567 static constexpr bool _ImplicitlyDefaultConstructibleTuple()
568 {
569 return __and_<__is_implicitly_default_constructible<_Elements>...>
570 ::value;
571 }
572 };
573
574 public:
575 template<typename _Dummy = void,
576 typename enable_if<_TC2<_Dummy>::
577 _ImplicitlyDefaultConstructibleTuple(),
578 bool>::type = true>
579 constexpr tuple()
580 : _Inherited() { }
581
582 template<typename _Dummy = void,
583 typename enable_if<_TC2<_Dummy>::
584 _DefaultConstructibleTuple()
585 &&
586 !_TC2<_Dummy>::
587 _ImplicitlyDefaultConstructibleTuple(),
588 bool>::type = false>
589 explicit constexpr tuple()
590 : _Inherited() { }
591
592 // Shortcut for the cases where constructors taking _Elements...
593 // need to be constrained.
594 template<typename _Dummy> using _TCC =
595 _TC<is_same<_Dummy, void>::value,
596 _Elements...>;
597
598 template<typename _Dummy = void,
599 typename enable_if<
600 _TCC<_Dummy>::template
601 _ConstructibleTuple<_Elements...>()
602 && _TCC<_Dummy>::template
603 _ImplicitlyConvertibleTuple<_Elements...>()
604 && (sizeof...(_Elements) >= 1),
605 bool>::type=true>
606 constexpr tuple(const _Elements&... __elements)
607 : _Inherited(__elements...) { }
608
609 template<typename _Dummy = void,
610 typename enable_if<
611 _TCC<_Dummy>::template
612 _ConstructibleTuple<_Elements...>()
613 && !_TCC<_Dummy>::template
614 _ImplicitlyConvertibleTuple<_Elements...>()
615 && (sizeof...(_Elements) >= 1),
616 bool>::type=false>
617 explicit constexpr tuple(const _Elements&... __elements)
618 : _Inherited(__elements...) { }
619
620 // Shortcut for the cases where constructors taking _UElements...
621 // need to be constrained.
622 template<typename... _UElements> using _TMC =
623 _TC<(sizeof...(_Elements) == sizeof...(_UElements)),
624 _Elements...>;
625
626 template<typename... _UElements, typename
627 enable_if<
628 _TC<sizeof...(_UElements) == 1, _Elements...>::template
629 _NotSameTuple<_UElements...>()
630 && _TMC<_UElements...>::template
631 _MoveConstructibleTuple<_UElements...>()
632 && _TMC<_UElements...>::template
633 _ImplicitlyMoveConvertibleTuple<_UElements...>()
634 && (sizeof...(_Elements) >= 1),
635 bool>::type=true>
636 constexpr tuple(_UElements&&... __elements)
637 : _Inherited(std::forward<_UElements>(__elements)...) { }
638
639 template<typename... _UElements, typename
640 enable_if<
641 _TC<sizeof...(_UElements) == 1, _Elements...>::template
642 _NotSameTuple<_UElements...>()
643 && _TMC<_UElements...>::template
644 _MoveConstructibleTuple<_UElements...>()
645 && !_TMC<_UElements...>::template
646 _ImplicitlyMoveConvertibleTuple<_UElements...>()
647 && (sizeof...(_Elements) >= 1),
648 bool>::type=false>
649 explicit constexpr tuple(_UElements&&... __elements)
650 : _Inherited(std::forward<_UElements>(__elements)...) { }
651
652 constexpr tuple(const tuple&) = default;
653
654 constexpr tuple(tuple&&) = default;
655
656 // Shortcut for the cases where constructors taking tuples
657 // must avoid creating temporaries.
658 template<typename _Dummy> using _TNTC =
659 _TC<is_same<_Dummy, void>::value && sizeof...(_Elements) == 1,
660 _Elements...>;
661
662 template<typename... _UElements, typename _Dummy = void, typename
663 enable_if<_TMC<_UElements...>::template
664 _ConstructibleTuple<_UElements...>()
665 && _TMC<_UElements...>::template
666 _ImplicitlyConvertibleTuple<_UElements...>()
667 && _TNTC<_Dummy>::template
668 _NonNestedTuple<const tuple<_UElements...>&>(),
669 bool>::type=true>
670 constexpr tuple(const tuple<_UElements...>& __in)
671 : _Inherited(static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
672 { }
673
674 template<typename... _UElements, typename _Dummy = void, typename
675 enable_if<_TMC<_UElements...>::template
676 _ConstructibleTuple<_UElements...>()
677 && !_TMC<_UElements...>::template
678 _ImplicitlyConvertibleTuple<_UElements...>()
679 && _TNTC<_Dummy>::template
680 _NonNestedTuple<const tuple<_UElements...>&>(),
681 bool>::type=false>
682 explicit constexpr tuple(const tuple<_UElements...>& __in)
683 : _Inherited(static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
684 { }
685
686 template<typename... _UElements, typename _Dummy = void, typename
687 enable_if<_TMC<_UElements...>::template
688 _MoveConstructibleTuple<_UElements...>()
689 && _TMC<_UElements...>::template
690 _ImplicitlyMoveConvertibleTuple<_UElements...>()
691 && _TNTC<_Dummy>::template
692 _NonNestedTuple<tuple<_UElements...>&&>(),
693 bool>::type=true>
694 constexpr tuple(tuple<_UElements...>&& __in)
695 : _Inherited(static_cast<_Tuple_impl<0, _UElements...>&&>(__in)) { }
696
697 template<typename... _UElements, typename _Dummy = void, typename
698 enable_if<_TMC<_UElements...>::template
699 _MoveConstructibleTuple<_UElements...>()
700 && !_TMC<_UElements...>::template
701 _ImplicitlyMoveConvertibleTuple<_UElements...>()
702 && _TNTC<_Dummy>::template
703 _NonNestedTuple<tuple<_UElements...>&&>(),
704 bool>::type=false>
705 explicit constexpr tuple(tuple<_UElements...>&& __in)
706 : _Inherited(static_cast<_Tuple_impl<0, _UElements...>&&>(__in)) { }
707
708 // Allocator-extended constructors.
709
710 template<typename _Alloc>
711 tuple(allocator_arg_t __tag, const _Alloc& __a)
712 : _Inherited(__tag, __a) { }
713
714 template<typename _Alloc, typename _Dummy = void,
715 typename enable_if<
716 _TCC<_Dummy>::template
717 _ConstructibleTuple<_Elements...>()
718 && _TCC<_Dummy>::template
719 _ImplicitlyConvertibleTuple<_Elements...>(),
720 bool>::type=true>
721 tuple(allocator_arg_t __tag, const _Alloc& __a,
722 const _Elements&... __elements)
723 : _Inherited(__tag, __a, __elements...) { }
724
725 template<typename _Alloc, typename _Dummy = void,
726 typename enable_if<
727 _TCC<_Dummy>::template
728 _ConstructibleTuple<_Elements...>()
729 && !_TCC<_Dummy>::template
730 _ImplicitlyConvertibleTuple<_Elements...>(),
731 bool>::type=false>
732 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
733 const _Elements&... __elements)
734 : _Inherited(__tag, __a, __elements...) { }
735
736 template<typename _Alloc, typename... _UElements, typename
737 enable_if<_TMC<_UElements...>::template
738 _MoveConstructibleTuple<_UElements...>()
739 && _TMC<_UElements...>::template
740 _ImplicitlyMoveConvertibleTuple<_UElements...>(),
741 bool>::type=true>
742 tuple(allocator_arg_t __tag, const _Alloc& __a,
743 _UElements&&... __elements)
744 : _Inherited(__tag, __a, std::forward<_UElements>(__elements)...)
745 { }
746
747 template<typename _Alloc, typename... _UElements, typename
748 enable_if<_TMC<_UElements...>::template
749 _MoveConstructibleTuple<_UElements...>()
750 && !_TMC<_UElements...>::template
751 _ImplicitlyMoveConvertibleTuple<_UElements...>(),
752 bool>::type=false>
753 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
754 _UElements&&... __elements)
755 : _Inherited(__tag, __a, std::forward<_UElements>(__elements)...)
756 { }
757
758 template<typename _Alloc>
759 tuple(allocator_arg_t __tag, const _Alloc& __a, const tuple& __in)
760 : _Inherited(__tag, __a, static_cast<const _Inherited&>(__in)) { }
761
762 template<typename _Alloc>
763 tuple(allocator_arg_t __tag, const _Alloc& __a, tuple&& __in)
764 : _Inherited(__tag, __a, static_cast<_Inherited&&>(__in)) { }
765
766 template<typename _Alloc, typename... _UElements, typename
767 enable_if<_TMC<_UElements...>::template
768 _ConstructibleTuple<_UElements...>()
769 && _TMC<_UElements...>::template
770 _ImplicitlyConvertibleTuple<_UElements...>(),
771 bool>::type=true>
772 tuple(allocator_arg_t __tag, const _Alloc& __a,
773 const tuple<_UElements...>& __in)
774 : _Inherited(__tag, __a,
775 static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
776 { }
777
778 template<typename _Alloc, typename... _UElements, typename
779 enable_if<_TMC<_UElements...>::template
780 _ConstructibleTuple<_UElements...>()
781 && !_TMC<_UElements...>::template
782 _ImplicitlyConvertibleTuple<_UElements...>(),
783 bool>::type=false>
784 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
785 const tuple<_UElements...>& __in)
786 : _Inherited(__tag, __a,
787 static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
788 { }
789
790 template<typename _Alloc, typename... _UElements, typename
791 enable_if<_TMC<_UElements...>::template
792 _MoveConstructibleTuple<_UElements...>()
793 && _TMC<_UElements...>::template
794 _ImplicitlyMoveConvertibleTuple<_UElements...>(),
795 bool>::type=true>
796 tuple(allocator_arg_t __tag, const _Alloc& __a,
797 tuple<_UElements...>&& __in)
798 : _Inherited(__tag, __a,
799 static_cast<_Tuple_impl<0, _UElements...>&&>(__in))
800 { }
801
802 template<typename _Alloc, typename... _UElements, typename
803 enable_if<_TMC<_UElements...>::template
804 _MoveConstructibleTuple<_UElements...>()
805 && !_TMC<_UElements...>::template
806 _ImplicitlyMoveConvertibleTuple<_UElements...>(),
807 bool>::type=false>
808 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
809 tuple<_UElements...>&& __in)
810 : _Inherited(__tag, __a,
811 static_cast<_Tuple_impl<0, _UElements...>&&>(__in))
812 { }
813
814 tuple&
815 operator=(const tuple& __in)
816 {
817 static_cast<_Inherited&>(*this) = __in;
818 return *this;
819 }
820
821 tuple&
822 operator=(tuple&& __in)
823 noexcept(is_nothrow_move_assignable<_Inherited>::value)
824 {
825 static_cast<_Inherited&>(*this) = std::move(__in);
826 return *this;
827 }
828
829 template<typename... _UElements, typename = typename
830 enable_if<sizeof...(_UElements)
831 == sizeof...(_Elements)>::type>
832 tuple&
833 operator=(const tuple<_UElements...>& __in)
834 {
835 static_cast<_Inherited&>(*this) = __in;
836 return *this;
837 }
838
839 template<typename... _UElements, typename = typename
840 enable_if<sizeof...(_UElements)
841 == sizeof...(_Elements)>::type>
842 tuple&
843 operator=(tuple<_UElements...>&& __in)
844 {
845 static_cast<_Inherited&>(*this) = std::move(__in);
846 return *this;
847 }
848
849 void
850 swap(tuple& __in)
851 noexcept(noexcept(__in._M_swap(__in)))
852 { _Inherited::_M_swap(__in); }
853 };
854
855 // Explicit specialization, zero-element tuple.
856 template<>
857 class tuple<>
858 {
859 public:
860 void swap(tuple&) noexcept { /* no-op */ }
861 };
862
863 /// Partial specialization, 2-element tuple.
864 /// Includes construction and assignment from a pair.
865 template<typename _T1, typename _T2>
866 class tuple<_T1, _T2> : public _Tuple_impl<0, _T1, _T2>
867 {
868 typedef _Tuple_impl<0, _T1, _T2> _Inherited;
869
870 public:
871 template <typename _U1 = _T1,
872 typename _U2 = _T2,
873 typename enable_if<__and_<
874 __is_implicitly_default_constructible<_U1>,
875 __is_implicitly_default_constructible<_U2>>
876 ::value, bool>::type = true>
877
878 constexpr tuple()
879 : _Inherited() { }
880
881 template <typename _U1 = _T1,
882 typename _U2 = _T2,
883 typename enable_if<
884 __and_<
885 is_default_constructible<_U1>,
886 is_default_constructible<_U2>,
887 __not_<
888 __and_<__is_implicitly_default_constructible<_U1>,
889 __is_implicitly_default_constructible<_U2>>>>
890 ::value, bool>::type = false>
891
892 explicit constexpr tuple()
893 : _Inherited() { }
894
895 // Shortcut for the cases where constructors taking _T1, _T2
896 // need to be constrained.
897 template<typename _Dummy> using _TCC =
898 _TC<is_same<_Dummy, void>::value, _T1, _T2>;
899
900 template<typename _Dummy = void, typename
901 enable_if<_TCC<_Dummy>::template
902 _ConstructibleTuple<_T1, _T2>()
903 && _TCC<_Dummy>::template
904 _ImplicitlyConvertibleTuple<_T1, _T2>(),
905 bool>::type = true>
906 constexpr tuple(const _T1& __a1, const _T2& __a2)
907 : _Inherited(__a1, __a2) { }
908
909 template<typename _Dummy = void, typename
910 enable_if<_TCC<_Dummy>::template
911 _ConstructibleTuple<_T1, _T2>()
912 && !_TCC<_Dummy>::template
913 _ImplicitlyConvertibleTuple<_T1, _T2>(),
914 bool>::type = false>
915 explicit constexpr tuple(const _T1& __a1, const _T2& __a2)
916 : _Inherited(__a1, __a2) { }
917
918 // Shortcut for the cases where constructors taking _U1, _U2
919 // need to be constrained.
920 using _TMC = _TC<true, _T1, _T2>;
921
922 template<typename _U1, typename _U2, typename
923 enable_if<_TMC::template
924 _MoveConstructibleTuple<_U1, _U2>()
925 && _TMC::template
926 _ImplicitlyMoveConvertibleTuple<_U1, _U2>()
927 && !is_same<typename decay<_U1>::type,
928 allocator_arg_t>::value,
929 bool>::type = true>
930 constexpr tuple(_U1&& __a1, _U2&& __a2)
931 : _Inherited(std::forward<_U1>(__a1), std::forward<_U2>(__a2)) { }
932
933 template<typename _U1, typename _U2, typename
934 enable_if<_TMC::template
935 _MoveConstructibleTuple<_U1, _U2>()
936 && !_TMC::template
937 _ImplicitlyMoveConvertibleTuple<_U1, _U2>()
938 && !is_same<typename decay<_U1>::type,
939 allocator_arg_t>::value,
940 bool>::type = false>
941 explicit constexpr tuple(_U1&& __a1, _U2&& __a2)
942 : _Inherited(std::forward<_U1>(__a1), std::forward<_U2>(__a2)) { }
943
944 constexpr tuple(const tuple&) = default;
945
946 constexpr tuple(tuple&&) = default;
947
948 template<typename _U1, typename _U2, typename
949 enable_if<_TMC::template
950 _ConstructibleTuple<_U1, _U2>()
951 && _TMC::template
952 _ImplicitlyConvertibleTuple<_U1, _U2>(),
953 bool>::type = true>
954 constexpr tuple(const tuple<_U1, _U2>& __in)
955 : _Inherited(static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in)) { }
956
957 template<typename _U1, typename _U2, typename
958 enable_if<_TMC::template
959 _ConstructibleTuple<_U1, _U2>()
960 && !_TMC::template
961 _ImplicitlyConvertibleTuple<_U1, _U2>(),
962 bool>::type = false>
963 explicit constexpr tuple(const tuple<_U1, _U2>& __in)
964 : _Inherited(static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in)) { }
965
966 template<typename _U1, typename _U2, typename
967 enable_if<_TMC::template
968 _MoveConstructibleTuple<_U1, _U2>()
969 && _TMC::template
970 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
971 bool>::type = true>
972 constexpr tuple(tuple<_U1, _U2>&& __in)
973 : _Inherited(static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in)) { }
974
975 template<typename _U1, typename _U2, typename
976 enable_if<_TMC::template
977 _MoveConstructibleTuple<_U1, _U2>()
978 && !_TMC::template
979 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
980 bool>::type = false>
981 explicit constexpr tuple(tuple<_U1, _U2>&& __in)
982 : _Inherited(static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in)) { }
983
984 template<typename _U1, typename _U2, typename
985 enable_if<_TMC::template
986 _ConstructibleTuple<_U1, _U2>()
987 && _TMC::template
988 _ImplicitlyConvertibleTuple<_U1, _U2>(),
989 bool>::type = true>
990 constexpr tuple(const pair<_U1, _U2>& __in)
991 : _Inherited(__in.first, __in.second) { }
992
993 template<typename _U1, typename _U2, typename
994 enable_if<_TMC::template
995 _ConstructibleTuple<_U1, _U2>()
996 && !_TMC::template
997 _ImplicitlyConvertibleTuple<_U1, _U2>(),
998 bool>::type = false>
999 explicit constexpr tuple(const pair<_U1, _U2>& __in)
1000 : _Inherited(__in.first, __in.second) { }
1001
1002 template<typename _U1, typename _U2, typename
1003 enable_if<_TMC::template
1004 _MoveConstructibleTuple<_U1, _U2>()
1005 && _TMC::template
1006 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1007 bool>::type = true>
1008 constexpr tuple(pair<_U1, _U2>&& __in)
1009 : _Inherited(std::forward<_U1>(__in.first),
1010 std::forward<_U2>(__in.second)) { }
1011
1012 template<typename _U1, typename _U2, typename
1013 enable_if<_TMC::template
1014 _MoveConstructibleTuple<_U1, _U2>()
1015 && !_TMC::template
1016 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1017 bool>::type = false>
1018 explicit constexpr tuple(pair<_U1, _U2>&& __in)
1019 : _Inherited(std::forward<_U1>(__in.first),
1020 std::forward<_U2>(__in.second)) { }
1021
1022 // Allocator-extended constructors.
1023
1024 template<typename _Alloc>
1025 tuple(allocator_arg_t __tag, const _Alloc& __a)
1026 : _Inherited(__tag, __a) { }
1027
1028 template<typename _Alloc, typename _Dummy = void,
1029 typename enable_if<
1030 _TCC<_Dummy>::template
1031 _ConstructibleTuple<_T1, _T2>()
1032 && _TCC<_Dummy>::template
1033 _ImplicitlyConvertibleTuple<_T1, _T2>(),
1034 bool>::type=true>
1035
1036 tuple(allocator_arg_t __tag, const _Alloc& __a,
1037 const _T1& __a1, const _T2& __a2)
1038 : _Inherited(__tag, __a, __a1, __a2) { }
1039
1040 template<typename _Alloc, typename _Dummy = void,
1041 typename enable_if<
1042 _TCC<_Dummy>::template
1043 _ConstructibleTuple<_T1, _T2>()
1044 && !_TCC<_Dummy>::template
1045 _ImplicitlyConvertibleTuple<_T1, _T2>(),
1046 bool>::type=false>
1047
1048 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
1049 const _T1& __a1, const _T2& __a2)
1050 : _Inherited(__tag, __a, __a1, __a2) { }
1051
1052 template<typename _Alloc, typename _U1, typename _U2, typename
1053 enable_if<_TMC::template
1054 _MoveConstructibleTuple<_U1, _U2>()
1055 && _TMC::template
1056 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1057 bool>::type = true>
1058 tuple(allocator_arg_t __tag, const _Alloc& __a, _U1&& __a1, _U2&& __a2)
1059 : _Inherited(__tag, __a, std::forward<_U1>(__a1),
1060 std::forward<_U2>(__a2)) { }
1061
1062 template<typename _Alloc, typename _U1, typename _U2, typename
1063 enable_if<_TMC::template
1064 _MoveConstructibleTuple<_U1, _U2>()
1065 && !_TMC::template
1066 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1067 bool>::type = false>
1068 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
1069 _U1&& __a1, _U2&& __a2)
1070 : _Inherited(__tag, __a, std::forward<_U1>(__a1),
1071 std::forward<_U2>(__a2)) { }
1072
1073 template<typename _Alloc>
1074 tuple(allocator_arg_t __tag, const _Alloc& __a, const tuple& __in)
1075 : _Inherited(__tag, __a, static_cast<const _Inherited&>(__in)) { }
1076
1077 template<typename _Alloc>
1078 tuple(allocator_arg_t __tag, const _Alloc& __a, tuple&& __in)
1079 : _Inherited(__tag, __a, static_cast<_Inherited&&>(__in)) { }
1080
1081 template<typename _Alloc, typename _U1, typename _U2, typename
1082 enable_if<_TMC::template
1083 _ConstructibleTuple<_U1, _U2>()
1084 && _TMC::template
1085 _ImplicitlyConvertibleTuple<_U1, _U2>(),
1086 bool>::type = true>
1087 tuple(allocator_arg_t __tag, const _Alloc& __a,
1088 const tuple<_U1, _U2>& __in)
1089 : _Inherited(__tag, __a,
1090 static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in))
1091 { }
1092
1093 template<typename _Alloc, typename _U1, typename _U2, typename
1094 enable_if<_TMC::template
1095 _ConstructibleTuple<_U1, _U2>()
1096 && !_TMC::template
1097 _ImplicitlyConvertibleTuple<_U1, _U2>(),
1098 bool>::type = false>
1099 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
1100 const tuple<_U1, _U2>& __in)
1101 : _Inherited(__tag, __a,
1102 static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in))
1103 { }
1104
1105 template<typename _Alloc, typename _U1, typename _U2, typename
1106 enable_if<_TMC::template
1107 _MoveConstructibleTuple<_U1, _U2>()
1108 && _TMC::template
1109 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1110 bool>::type = true>
1111 tuple(allocator_arg_t __tag, const _Alloc& __a, tuple<_U1, _U2>&& __in)
1112 : _Inherited(__tag, __a, static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in))
1113 { }
1114
1115 template<typename _Alloc, typename _U1, typename _U2, typename
1116 enable_if<_TMC::template
1117 _MoveConstructibleTuple<_U1, _U2>()
1118 && !_TMC::template
1119 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1120 bool>::type = false>
1121 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
1122 tuple<_U1, _U2>&& __in)
1123 : _Inherited(__tag, __a, static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in))
1124 { }
1125
1126 template<typename _Alloc, typename _U1, typename _U2, typename
1127 enable_if<_TMC::template
1128 _ConstructibleTuple<_U1, _U2>()
1129 && _TMC::template
1130 _ImplicitlyConvertibleTuple<_U1, _U2>(),
1131 bool>::type = true>
1132 tuple(allocator_arg_t __tag, const _Alloc& __a,
1133 const pair<_U1, _U2>& __in)
1134 : _Inherited(__tag, __a, __in.first, __in.second) { }
1135
1136 template<typename _Alloc, typename _U1, typename _U2, typename
1137 enable_if<_TMC::template
1138 _ConstructibleTuple<_U1, _U2>()
1139 && !_TMC::template
1140 _ImplicitlyConvertibleTuple<_U1, _U2>(),
1141 bool>::type = false>
1142 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
1143 const pair<_U1, _U2>& __in)
1144 : _Inherited(__tag, __a, __in.first, __in.second) { }
1145
1146 template<typename _Alloc, typename _U1, typename _U2, typename
1147 enable_if<_TMC::template
1148 _MoveConstructibleTuple<_U1, _U2>()
1149 && _TMC::template
1150 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1151 bool>::type = true>
1152 tuple(allocator_arg_t __tag, const _Alloc& __a, pair<_U1, _U2>&& __in)
1153 : _Inherited(__tag, __a, std::forward<_U1>(__in.first),
1154 std::forward<_U2>(__in.second)) { }
1155
1156 template<typename _Alloc, typename _U1, typename _U2, typename
1157 enable_if<_TMC::template
1158 _MoveConstructibleTuple<_U1, _U2>()
1159 && !_TMC::template
1160 _ImplicitlyMoveConvertibleTuple<_U1, _U2>(),
1161 bool>::type = false>
1162 explicit tuple(allocator_arg_t __tag, const _Alloc& __a,
1163 pair<_U1, _U2>&& __in)
1164 : _Inherited(__tag, __a, std::forward<_U1>(__in.first),
1165 std::forward<_U2>(__in.second)) { }
1166
1167 tuple&
1168 operator=(const tuple& __in)
1169 {
1170 static_cast<_Inherited&>(*this) = __in;
1171 return *this;
1172 }
1173
1174 tuple&
1175 operator=(tuple&& __in)
1176 noexcept(is_nothrow_move_assignable<_Inherited>::value)
1177 {
1178 static_cast<_Inherited&>(*this) = std::move(__in);
1179 return *this;
1180 }
1181
1182 template<typename _U1, typename _U2>
1183 tuple&
1184 operator=(const tuple<_U1, _U2>& __in)
1185 {
1186 static_cast<_Inherited&>(*this) = __in;
1187 return *this;
1188 }
1189
1190 template<typename _U1, typename _U2>
1191 tuple&
1192 operator=(tuple<_U1, _U2>&& __in)
1193 {
1194 static_cast<_Inherited&>(*this) = std::move(__in);
1195 return *this;
1196 }
1197
1198 template<typename _U1, typename _U2>
1199 tuple&
1200 operator=(const pair<_U1, _U2>& __in)
1201 {
1202 this->_M_head(*this) = __in.first;
1203 this->_M_tail(*this)._M_head(*this) = __in.second;
1204 return *this;
1205 }
1206
1207 template<typename _U1, typename _U2>
1208 tuple&
1209 operator=(pair<_U1, _U2>&& __in)
1210 {
1211 this->_M_head(*this) = std::forward<_U1>(__in.first);
1212 this->_M_tail(*this)._M_head(*this) = std::forward<_U2>(__in.second);
1213 return *this;
1214 }
1215
1216 void
1217 swap(tuple& __in)
1218 noexcept(noexcept(__in._M_swap(__in)))
1219 { _Inherited::_M_swap(__in); }
1220 };
1221
1222
1223 /**
1224 * Recursive case for tuple_element: strip off the first element in
1225 * the tuple and retrieve the (i-1)th element of the remaining tuple.
1226 */
1227 template<std::size_t __i, typename _Head, typename... _Tail>
1228 struct tuple_element<__i, tuple<_Head, _Tail...> >
1229 : tuple_element<__i - 1, tuple<_Tail...> > { };
1230
1231 /**
1232 * Basis case for tuple_element: The first element is the one we're seeking.
1233 */
1234 template<typename _Head, typename... _Tail>
1235 struct tuple_element<0, tuple<_Head, _Tail...> >
1236 {
1237 typedef _Head type;
1238 };
1239
1240 /// class tuple_size
1241 template<typename... _Elements>
1242 struct tuple_size<tuple<_Elements...>>
1243 : public integral_constant<std::size_t, sizeof...(_Elements)> { };
1244
1245 template<std::size_t __i, typename _Head, typename... _Tail>
1246 constexpr _Head&
1247 __get_helper(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
1248 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
1249
1250 template<std::size_t __i, typename _Head, typename... _Tail>
1251 constexpr const _Head&
1252 __get_helper(const _Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
1253 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
1254
1255 /// Return a reference to the ith element of a tuple.
1256 template<std::size_t __i, typename... _Elements>
1257 constexpr __tuple_element_t<__i, tuple<_Elements...>>&
1258 get(tuple<_Elements...>& __t) noexcept
1259 { return std::__get_helper<__i>(__t); }
1260
1261 /// Return a const reference to the ith element of a const tuple.
1262 template<std::size_t __i, typename... _Elements>
1263 constexpr const __tuple_element_t<__i, tuple<_Elements...>>&
1264 get(const tuple<_Elements...>& __t) noexcept
1265 { return std::__get_helper<__i>(__t); }
1266
1267 /// Return an rvalue reference to the ith element of a tuple rvalue.
1268 template<std::size_t __i, typename... _Elements>
1269 constexpr __tuple_element_t<__i, tuple<_Elements...>>&&
1270 get(tuple<_Elements...>&& __t) noexcept
1271 {
1272 typedef __tuple_element_t<__i, tuple<_Elements...>> __element_type;
1273 return std::forward<__element_type&&>(std::get<__i>(__t));
1274 }
1275
1276#if __cplusplus > 201103L
1277
1278#define __cpp_lib_tuples_by_type 201304
1279
1280 template<typename _Head, size_t __i, typename... _Tail>
1281 constexpr _Head&
1282 __get_helper2(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
1283 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
1284
1285 template<typename _Head, size_t __i, typename... _Tail>
1286 constexpr const _Head&
1287 __get_helper2(const _Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
1288 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
1289
1290 /// Return a reference to the unique element of type _Tp of a tuple.
1291 template <typename _Tp, typename... _Types>
1292 constexpr _Tp&
1293 get(tuple<_Types...>& __t) noexcept
1294 { return std::__get_helper2<_Tp>(__t); }
1295
1296 /// Return a reference to the unique element of type _Tp of a tuple rvalue.
1297 template <typename _Tp, typename... _Types>
1298 constexpr _Tp&&
1299 get(tuple<_Types...>&& __t) noexcept
1300 { return std::forward<_Tp&&>(std::__get_helper2<_Tp>(__t)); }
1301
1302 /// Return a const reference to the unique element of type _Tp of a tuple.
1303 template <typename _Tp, typename... _Types>
1304 constexpr const _Tp&
1305 get(const tuple<_Types...>& __t) noexcept
1306 { return std::__get_helper2<_Tp>(__t); }
1307#endif
1308
1309 // This class performs the comparison operations on tuples
1310 template<typename _Tp, typename _Up, size_t __i, size_t __size>
1311 struct __tuple_compare
1312 {
1313 static constexpr bool
1314 __eq(const _Tp& __t, const _Up& __u)
1315 {
1316 return bool(std::get<__i>(__t) == std::get<__i>(__u))
1317 && __tuple_compare<_Tp, _Up, __i + 1, __size>::__eq(__t, __u);
1318 }
1319
1320 static constexpr bool
1321 __less(const _Tp& __t, const _Up& __u)
1322 {
1323 return bool(std::get<__i>(__t) < std::get<__i>(__u))
1324 || (!bool(std::get<__i>(__u) < std::get<__i>(__t))
1325 && __tuple_compare<_Tp, _Up, __i + 1, __size>::__less(__t, __u));
1326 }
1327 };
1328
1329 template<typename _Tp, typename _Up, size_t __size>
1330 struct __tuple_compare<_Tp, _Up, __size, __size>
1331 {
1332 static constexpr bool
1333 __eq(const _Tp&, const _Up&) { return true; }
1334
1335 static constexpr bool
1336 __less(const _Tp&, const _Up&) { return false; }
1337 };
1338
1339 template<typename... _TElements, typename... _UElements>
1340 constexpr bool
1341 operator==(const tuple<_TElements...>& __t,
1342 const tuple<_UElements...>& __u)
1343 {
1344 static_assert(sizeof...(_TElements) == sizeof...(_UElements),
1345 "tuple objects can only be compared if they have equal sizes.");
1346 using __compare = __tuple_compare<tuple<_TElements...>,
1347 tuple<_UElements...>,
1348 0, sizeof...(_TElements)>;
1349 return __compare::__eq(__t, __u);
1350 }
1351
1352 template<typename... _TElements, typename... _UElements>
1353 constexpr bool
1354 operator<(const tuple<_TElements...>& __t,
1355 const tuple<_UElements...>& __u)
1356 {
1357 static_assert(sizeof...(_TElements) == sizeof...(_UElements),
1358 "tuple objects can only be compared if they have equal sizes.");
1359 using __compare = __tuple_compare<tuple<_TElements...>,
1360 tuple<_UElements...>,
1361 0, sizeof...(_TElements)>;
1362 return __compare::__less(__t, __u);
1363 }
1364
1365 template<typename... _TElements, typename... _UElements>
1366 constexpr bool
1367 operator!=(const tuple<_TElements...>& __t,
1368 const tuple<_UElements...>& __u)
1369 { return !(__t == __u); }
1370
1371 template<typename... _TElements, typename... _UElements>
1372 constexpr bool
1373 operator>(const tuple<_TElements...>& __t,
1374 const tuple<_UElements...>& __u)
1375 { return __u < __t; }
1376
1377 template<typename... _TElements, typename... _UElements>
1378 constexpr bool
1379 operator<=(const tuple<_TElements...>& __t,
1380 const tuple<_UElements...>& __u)
1381 { return !(__u < __t); }
1382
1383 template<typename... _TElements, typename... _UElements>
1384 constexpr bool
1385 operator>=(const tuple<_TElements...>& __t,
1386 const tuple<_UElements...>& __u)
1387 { return !(__t < __u); }
1388
1389 // NB: DR 705.
1390 template<typename... _Elements>
1391 constexpr tuple<typename __decay_and_strip<_Elements>::__type...>
1392 make_tuple(_Elements&&... __args)
1393 {
1394 typedef tuple<typename __decay_and_strip<_Elements>::__type...>
1395 __result_type;
1396 return __result_type(std::forward<_Elements>(__args)...);
1397 }
1398
1399 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1400 // 2275. Why is forward_as_tuple not constexpr?
1401 template<typename... _Elements>
1402 constexpr tuple<_Elements&&...>
1403 forward_as_tuple(_Elements&&... __args) noexcept
1404 { return tuple<_Elements&&...>(std::forward<_Elements>(__args)...); }
1405
1406 template<typename... _Tps>
1407 struct __is_tuple_like_impl<tuple<_Tps...>> : true_type
1408 { };
1409
1410 // Internal type trait that allows us to sfinae-protect tuple_cat.
1411 template<typename _Tp>
1412 struct __is_tuple_like
1413 : public __is_tuple_like_impl<typename std::remove_cv
1414 <typename std::remove_reference<_Tp>::type>::type>::type
1415 { };
1416
1417 template<size_t, typename, typename, size_t>
1418 struct __make_tuple_impl;
1419
1420 template<size_t _Idx, typename _Tuple, typename... _Tp, size_t _Nm>
1421 struct __make_tuple_impl<_Idx, tuple<_Tp...>, _Tuple, _Nm>
1422 : __make_tuple_impl<_Idx + 1,
1423 tuple<_Tp..., __tuple_element_t<_Idx, _Tuple>>,
1424 _Tuple, _Nm>
1425 { };
1426
1427 template<std::size_t _Nm, typename _Tuple, typename... _Tp>
1428 struct __make_tuple_impl<_Nm, tuple<_Tp...>, _Tuple, _Nm>
1429 {
1430 typedef tuple<_Tp...> __type;
1431 };
1432
1433 template<typename _Tuple>
1434 struct __do_make_tuple
1435 : __make_tuple_impl<0, tuple<>, _Tuple, std::tuple_size<_Tuple>::value>
1436 { };
1437
1438 // Returns the std::tuple equivalent of a tuple-like type.
1439 template<typename _Tuple>
1440 struct __make_tuple
1441 : public __do_make_tuple<typename std::remove_cv
1442 <typename std::remove_reference<_Tuple>::type>::type>
1443 { };
1444
1445 // Combines several std::tuple's into a single one.
1446 template<typename...>
1447 struct __combine_tuples;
1448
1449 template<>
1450 struct __combine_tuples<>
1451 {
1452 typedef tuple<> __type;
1453 };
1454
1455 template<typename... _Ts>
1456 struct __combine_tuples<tuple<_Ts...>>
1457 {
1458 typedef tuple<_Ts...> __type;
1459 };
1460
1461 template<typename... _T1s, typename... _T2s, typename... _Rem>
1462 struct __combine_tuples<tuple<_T1s...>, tuple<_T2s...>, _Rem...>
1463 {
1464 typedef typename __combine_tuples<tuple<_T1s..., _T2s...>,
1465 _Rem...>::__type __type;
1466 };
1467
1468 // Computes the result type of tuple_cat given a set of tuple-like types.
1469 template<typename... _Tpls>
1470 struct __tuple_cat_result
1471 {
1472 typedef typename __combine_tuples
1473 <typename __make_tuple<_Tpls>::__type...>::__type __type;
1474 };
1475
1476 // Helper to determine the index set for the first tuple-like
1477 // type of a given set.
1478 template<typename...>
1479 struct __make_1st_indices;
1480
1481 template<>
1482 struct __make_1st_indices<>
1483 {
1484 typedef std::_Index_tuple<> __type;
1485 };
1486
1487 template<typename _Tp, typename... _Tpls>
1488 struct __make_1st_indices<_Tp, _Tpls...>
1489 {
1490 typedef typename std::_Build_index_tuple<std::tuple_size<
1491 typename std::remove_reference<_Tp>::type>::value>::__type __type;
1492 };
1493
1494 // Performs the actual concatenation by step-wise expanding tuple-like
1495 // objects into the elements, which are finally forwarded into the
1496 // result tuple.
1497 template<typename _Ret, typename _Indices, typename... _Tpls>
1498 struct __tuple_concater;
1499
1500 template<typename _Ret, std::size_t... _Is, typename _Tp, typename... _Tpls>
1501 struct __tuple_concater<_Ret, std::_Index_tuple<_Is...>, _Tp, _Tpls...>
1502 {
1503 template<typename... _Us>
1504 static constexpr _Ret
1505 _S_do(_Tp&& __tp, _Tpls&&... __tps, _Us&&... __us)
1506 {
1507 typedef typename __make_1st_indices<_Tpls...>::__type __idx;
1508 typedef __tuple_concater<_Ret, __idx, _Tpls...> __next;
1509 return __next::_S_do(std::forward<_Tpls>(__tps)...,
1510 std::forward<_Us>(__us)...,
1511 std::get<_Is>(std::forward<_Tp>(__tp))...);
1512 }
1513 };
1514
1515 template<typename _Ret>
1516 struct __tuple_concater<_Ret, std::_Index_tuple<>>
1517 {
1518 template<typename... _Us>
1519 static constexpr _Ret
1520 _S_do(_Us&&... __us)
1521 {
1522 return _Ret(std::forward<_Us>(__us)...);
1523 }
1524 };
1525
1526 /// tuple_cat
1527 template<typename... _Tpls, typename = typename
1528 enable_if<__and_<__is_tuple_like<_Tpls>...>::value>::type>
1529 constexpr auto
1530 tuple_cat(_Tpls&&... __tpls)
1531 -> typename __tuple_cat_result<_Tpls...>::__type
1532 {
1533 typedef typename __tuple_cat_result<_Tpls...>::__type __ret;
1534 typedef typename __make_1st_indices<_Tpls...>::__type __idx;
1535 typedef __tuple_concater<__ret, __idx, _Tpls...> __concater;
1536 return __concater::_S_do(std::forward<_Tpls>(__tpls)...);
1537 }
1538
1539 // _GLIBCXX_RESOLVE_LIB_DEFECTS
1540 // 2301. Why is tie not constexpr?
1541 /// tie
1542 template<typename... _Elements>
1543 constexpr tuple<_Elements&...>
1544 tie(_Elements&... __args) noexcept
1545 { return tuple<_Elements&...>(__args...); }
1546
1547 /// swap
1548 template<typename... _Elements>
1549 inline void
1550 swap(tuple<_Elements...>& __x, tuple<_Elements...>& __y)
1551 noexcept(noexcept(__x.swap(__y)))
1552 { __x.swap(__y); }
1553
1554 // A class (and instance) which can be used in 'tie' when an element
1555 // of a tuple is not required
1556 struct _Swallow_assign
1557 {
1558 template<class _Tp>
1559 const _Swallow_assign&
1560 operator=(const _Tp&) const
1561 { return *this; }
1562 };
1563
1564 const _Swallow_assign ignore{};
1565
1566 /// Partial specialization for tuples
1567 template<typename... _Types, typename _Alloc>
1568 struct uses_allocator<tuple<_Types...>, _Alloc> : true_type { };
1569
1570 // See stl_pair.h...
1571 template<class _T1, class _T2>
1572 template<typename... _Args1, typename... _Args2>
1573 inline
1574 pair<_T1, _T2>::
1575 pair(piecewise_construct_t,
1576 tuple<_Args1...> __first, tuple<_Args2...> __second)
1577 : pair(__first, __second,
1578 typename _Build_index_tuple<sizeof...(_Args1)>::__type(),
1579 typename _Build_index_tuple<sizeof...(_Args2)>::__type())
1580 { }
1581
1582 template<class _T1, class _T2>
1583 template<typename... _Args1, std::size_t... _Indexes1,
1584 typename... _Args2, std::size_t... _Indexes2>
1585 inline
1586 pair<_T1, _T2>::
1587 pair(tuple<_Args1...>& __tuple1, tuple<_Args2...>& __tuple2,
1588 _Index_tuple<_Indexes1...>, _Index_tuple<_Indexes2...>)
1589 : first(std::forward<_Args1>(std::get<_Indexes1>(__tuple1))...),
1590 second(std::forward<_Args2>(std::get<_Indexes2>(__tuple2))...)
1591 { }
1592
1593 /// @}
1594
1595_GLIBCXX_END_NAMESPACE_VERSION
1596} // namespace std
1597
1598#endif // C++11
1599
1600#endif // _GLIBCXX_TUPLE
1601