3 // Copyright (C) 2007-2015 Free Software Foundation, Inc.
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)
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.
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.
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/>.
25 /** @file include/tuple
26 * This is a Standard C++ Library header.
29 #ifndef _GLIBCXX_TUPLE
30 #define _GLIBCXX_TUPLE 1
32 #pragma GCC system_header
34 #if __cplusplus < 201103L
35 # include <bits/c++0x_warning.h>
40 #include <bits/uses_allocator.h>
42 namespace std _GLIBCXX_VISIBILITY(default)
44 _GLIBCXX_BEGIN_NAMESPACE_VERSION
47 * @addtogroup utilities
51 template<std::size_t _Idx, typename _Head, bool _IsEmptyNotFinal>
54 template<std::size_t _Idx, typename _Head>
55 struct _Head_base<_Idx, _Head, true>
58 constexpr _Head_base()
61 constexpr _Head_base(const _Head& __h)
64 constexpr _Head_base(const _Head_base&) = default;
65 constexpr _Head_base(_Head_base&&) = default;
67 template<typename _UHead>
68 constexpr _Head_base(_UHead&& __h)
69 : _Head(std::forward<_UHead>(__h)) { }
71 _Head_base(allocator_arg_t, __uses_alloc0)
74 template<typename _Alloc>
75 _Head_base(allocator_arg_t, __uses_alloc1<_Alloc> __a)
76 : _Head(allocator_arg, *__a._M_a) { }
78 template<typename _Alloc>
79 _Head_base(allocator_arg_t, __uses_alloc2<_Alloc> __a)
80 : _Head(*__a._M_a) { }
82 template<typename _UHead>
83 _Head_base(__uses_alloc0, _UHead&& __uhead)
84 : _Head(std::forward<_UHead>(__uhead)) { }
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)) { }
90 template<typename _Alloc, typename _UHead>
91 _Head_base(__uses_alloc2<_Alloc> __a, _UHead&& __uhead)
92 : _Head(std::forward<_UHead>(__uhead), *__a._M_a) { }
94 static constexpr _Head&
95 _M_head(_Head_base& __b) noexcept { return __b; }
97 static constexpr const _Head&
98 _M_head(const _Head_base& __b) noexcept { return __b; }
101 template<std::size_t _Idx, typename _Head>
102 struct _Head_base<_Idx, _Head, false>
104 constexpr _Head_base()
107 constexpr _Head_base(const _Head& __h)
108 : _M_head_impl(__h) { }
110 constexpr _Head_base(const _Head_base&) = default;
111 constexpr _Head_base(_Head_base&&) = default;
113 template<typename _UHead>
114 constexpr _Head_base(_UHead&& __h)
115 : _M_head_impl(std::forward<_UHead>(__h)) { }
117 _Head_base(allocator_arg_t, __uses_alloc0)
120 template<typename _Alloc>
121 _Head_base(allocator_arg_t, __uses_alloc1<_Alloc> __a)
122 : _M_head_impl(allocator_arg, *__a._M_a) { }
124 template<typename _Alloc>
125 _Head_base(allocator_arg_t, __uses_alloc2<_Alloc> __a)
126 : _M_head_impl(*__a._M_a) { }
128 template<typename _UHead>
129 _Head_base(__uses_alloc0, _UHead&& __uhead)
130 : _M_head_impl(std::forward<_UHead>(__uhead)) { }
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))
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) { }
141 static constexpr _Head&
142 _M_head(_Head_base& __b) noexcept { return __b._M_head_impl; }
144 static constexpr const _Head&
145 _M_head(const _Head_base& __b) noexcept { return __b._M_head_impl; }
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
158 template<std::size_t _Idx, typename... _Elements>
161 template<typename _Tp>
162 struct __is_empty_non_tuple : is_empty<_Tp> { };
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 { };
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;
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).
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>
184 template<std::size_t, typename...> friend class _Tuple_impl;
186 typedef _Tuple_impl<_Idx + 1, _Tail...> _Inherited;
187 typedef _Head_base<_Idx, _Head, __empty_not_final<_Head>::value> _Base;
189 static constexpr _Head&
190 _M_head(_Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
192 static constexpr const _Head&
193 _M_head(const _Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
195 static constexpr _Inherited&
196 _M_tail(_Tuple_impl& __t) noexcept { return __t; }
198 static constexpr const _Inherited&
199 _M_tail(const _Tuple_impl& __t) noexcept { return __t; }
201 constexpr _Tuple_impl()
202 : _Inherited(), _Base() { }
205 constexpr _Tuple_impl(const _Head& __head, const _Tail&... __tail)
206 : _Inherited(__tail...), _Base(__head) { }
208 template<typename _UHead, typename... _UTail, typename = typename
209 enable_if<sizeof...(_Tail) == sizeof...(_UTail)>::type>
211 constexpr _Tuple_impl(_UHead&& __head, _UTail&&... __tail)
212 : _Inherited(std::forward<_UTail>(__tail)...),
213 _Base(std::forward<_UHead>(__head)) { }
215 constexpr _Tuple_impl(const _Tuple_impl&) = default;
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))) { }
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)) { }
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))) { }
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)) { }
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) { }
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)) { }
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)) { }
262 template<typename _Alloc>
263 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
265 : _Inherited(__tag, __a, std::move(_M_tail(__in))),
266 _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
267 std::forward<_Head>(_M_head(__in))) { }
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)) { }
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),
284 (_Tuple_impl<_Idx, _UHead, _UTails...>::_M_head(__in))) { }
287 operator=(const _Tuple_impl& __in)
289 _M_head(*this) = _M_head(__in);
290 _M_tail(*this) = _M_tail(__in);
295 operator=(_Tuple_impl&& __in)
296 noexcept(__and_<is_nothrow_move_assignable<_Head>,
297 is_nothrow_move_assignable<_Inherited>>::value)
299 _M_head(*this) = std::forward<_Head>(_M_head(__in));
300 _M_tail(*this) = std::move(_M_tail(__in));
304 template<typename... _UElements>
306 operator=(const _Tuple_impl<_Idx, _UElements...>& __in)
308 _M_head(*this) = _Tuple_impl<_Idx, _UElements...>::_M_head(__in);
309 _M_tail(*this) = _Tuple_impl<_Idx, _UElements...>::_M_tail(__in);
313 template<typename _UHead, typename... _UTails>
315 operator=(_Tuple_impl<_Idx, _UHead, _UTails...>&& __in)
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));
326 _M_swap(_Tuple_impl& __in)
327 noexcept(noexcept(swap(std::declval<_Head&>(),
328 std::declval<_Head&>()))
329 && noexcept(_M_tail(__in)._M_swap(_M_tail(__in))))
332 swap(_M_head(*this), _M_head(__in));
333 _Inherited::_M_swap(_M_tail(__in));
337 // Basis case of inheritance recursion.
338 template<std::size_t _Idx, typename _Head>
339 struct _Tuple_impl<_Idx, _Head>
340 : private _Head_base<_Idx, _Head, __empty_not_final<_Head>::value>
342 template<std::size_t, typename...> friend class _Tuple_impl;
344 typedef _Head_base<_Idx, _Head, __empty_not_final<_Head>::value> _Base;
346 static constexpr _Head&
347 _M_head(_Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
349 static constexpr const _Head&
350 _M_head(const _Tuple_impl& __t) noexcept { return _Base::_M_head(__t); }
352 constexpr _Tuple_impl()
356 constexpr _Tuple_impl(const _Head& __head)
359 template<typename _UHead>
361 constexpr _Tuple_impl(_UHead&& __head)
362 : _Base(std::forward<_UHead>(__head)) { }
364 constexpr _Tuple_impl(const _Tuple_impl&) = default;
367 _Tuple_impl(_Tuple_impl&& __in)
368 noexcept(is_nothrow_move_constructible<_Head>::value)
369 : _Base(std::forward<_Head>(_M_head(__in))) { }
371 template<typename _UHead>
372 constexpr _Tuple_impl(const _Tuple_impl<_Idx, _UHead>& __in)
373 : _Base(_Tuple_impl<_Idx, _UHead>::_M_head(__in)) { }
375 template<typename _UHead>
376 constexpr _Tuple_impl(_Tuple_impl<_Idx, _UHead>&& __in)
377 : _Base(std::forward<_UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in)))
380 template<typename _Alloc>
381 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a)
382 : _Base(__tag, __use_alloc<_Head>(__a)) { }
384 template<typename _Alloc>
385 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
387 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a), __head) { }
389 template<typename _Alloc, typename _UHead>
390 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
392 : _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
393 std::forward<_UHead>(__head)) { }
395 template<typename _Alloc>
396 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
397 const _Tuple_impl& __in)
398 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a), _M_head(__in)) { }
400 template<typename _Alloc>
401 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
403 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
404 std::forward<_Head>(_M_head(__in))) { }
406 template<typename _Alloc, typename _UHead>
407 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
408 const _Tuple_impl<_Idx, _UHead>& __in)
409 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a),
410 _Tuple_impl<_Idx, _UHead>::_M_head(__in)) { }
412 template<typename _Alloc, typename _UHead>
413 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a,
414 _Tuple_impl<_Idx, _UHead>&& __in)
415 : _Base(__use_alloc<_Head, _Alloc, _UHead>(__a),
416 std::forward<_UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in)))
420 operator=(const _Tuple_impl& __in)
422 _M_head(*this) = _M_head(__in);
427 operator=(_Tuple_impl&& __in)
428 noexcept(is_nothrow_move_assignable<_Head>::value)
430 _M_head(*this) = std::forward<_Head>(_M_head(__in));
434 template<typename _UHead>
436 operator=(const _Tuple_impl<_Idx, _UHead>& __in)
438 _M_head(*this) = _Tuple_impl<_Idx, _UHead>::_M_head(__in);
442 template<typename _UHead>
444 operator=(_Tuple_impl<_Idx, _UHead>&& __in)
447 = std::forward<_UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in));
453 _M_swap(_Tuple_impl& __in)
454 noexcept(noexcept(swap(std::declval<_Head&>(), std::declval<_Head&>())))
457 swap(_M_head(*this), _M_head(__in));
461 /// Primary class template, tuple
462 template<typename... _Elements>
463 class tuple : public _Tuple_impl<0, _Elements...>
465 typedef _Tuple_impl<0, _Elements...> _Inherited;
472 constexpr tuple(const _Elements&... __elements)
473 : _Inherited(__elements...) { }
475 template<typename... _UElements, typename = typename
476 enable_if<__and_<is_convertible<_UElements,
477 _Elements>...>::value>::type>
479 constexpr tuple(_UElements&&... __elements)
480 : _Inherited(std::forward<_UElements>(__elements)...) { }
482 constexpr tuple(const tuple&) = default;
484 constexpr tuple(tuple&&) = default;
486 template<typename... _UElements, typename = typename
487 enable_if<__and_<is_convertible<const _UElements&,
488 _Elements>...>::value>::type>
489 constexpr tuple(const tuple<_UElements...>& __in)
490 : _Inherited(static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
493 template<typename... _UElements, typename = typename
494 enable_if<__and_<is_convertible<_UElements,
495 _Elements>...>::value>::type>
496 constexpr tuple(tuple<_UElements...>&& __in)
497 : _Inherited(static_cast<_Tuple_impl<0, _UElements...>&&>(__in)) { }
499 // Allocator-extended constructors.
501 template<typename _Alloc>
502 tuple(allocator_arg_t __tag, const _Alloc& __a)
503 : _Inherited(__tag, __a) { }
505 template<typename _Alloc>
506 tuple(allocator_arg_t __tag, const _Alloc& __a,
507 const _Elements&... __elements)
508 : _Inherited(__tag, __a, __elements...) { }
510 template<typename _Alloc, typename... _UElements, typename = typename
511 enable_if<sizeof...(_UElements)
512 == sizeof...(_Elements)>::type>
513 tuple(allocator_arg_t __tag, const _Alloc& __a,
514 _UElements&&... __elements)
515 : _Inherited(__tag, __a, std::forward<_UElements>(__elements)...)
518 template<typename _Alloc>
519 tuple(allocator_arg_t __tag, const _Alloc& __a, const tuple& __in)
520 : _Inherited(__tag, __a, static_cast<const _Inherited&>(__in)) { }
522 template<typename _Alloc>
523 tuple(allocator_arg_t __tag, const _Alloc& __a, tuple&& __in)
524 : _Inherited(__tag, __a, static_cast<_Inherited&&>(__in)) { }
526 template<typename _Alloc, typename... _UElements, typename = typename
527 enable_if<sizeof...(_UElements)
528 == sizeof...(_Elements)>::type>
529 tuple(allocator_arg_t __tag, const _Alloc& __a,
530 const tuple<_UElements...>& __in)
531 : _Inherited(__tag, __a,
532 static_cast<const _Tuple_impl<0, _UElements...>&>(__in))
535 template<typename _Alloc, typename... _UElements, typename = typename
536 enable_if<sizeof...(_UElements)
537 == sizeof...(_Elements)>::type>
538 tuple(allocator_arg_t __tag, const _Alloc& __a,
539 tuple<_UElements...>&& __in)
540 : _Inherited(__tag, __a,
541 static_cast<_Tuple_impl<0, _UElements...>&&>(__in))
545 operator=(const tuple& __in)
547 static_cast<_Inherited&>(*this) = __in;
552 operator=(tuple&& __in)
553 noexcept(is_nothrow_move_assignable<_Inherited>::value)
555 static_cast<_Inherited&>(*this) = std::move(__in);
559 template<typename... _UElements, typename = typename
560 enable_if<sizeof...(_UElements)
561 == sizeof...(_Elements)>::type>
563 operator=(const tuple<_UElements...>& __in)
565 static_cast<_Inherited&>(*this) = __in;
569 template<typename... _UElements, typename = typename
570 enable_if<sizeof...(_UElements)
571 == sizeof...(_Elements)>::type>
573 operator=(tuple<_UElements...>&& __in)
575 static_cast<_Inherited&>(*this) = std::move(__in);
581 noexcept(noexcept(__in._M_swap(__in)))
582 { _Inherited::_M_swap(__in); }
585 // Explicit specialization, zero-element tuple.
590 void swap(tuple&) noexcept { /* no-op */ }
593 /// Partial specialization, 2-element tuple.
594 /// Includes construction and assignment from a pair.
595 template<typename _T1, typename _T2>
596 class tuple<_T1, _T2> : public _Tuple_impl<0, _T1, _T2>
598 typedef _Tuple_impl<0, _T1, _T2> _Inherited;
605 constexpr tuple(const _T1& __a1, const _T2& __a2)
606 : _Inherited(__a1, __a2) { }
608 template<typename _U1, typename _U2, typename = typename
609 enable_if<__and_<is_convertible<_U1, _T1>,
610 is_convertible<_U2, _T2>>::value>::type>
612 constexpr tuple(_U1&& __a1, _U2&& __a2)
613 : _Inherited(std::forward<_U1>(__a1), std::forward<_U2>(__a2)) { }
615 constexpr tuple(const tuple&) = default;
617 constexpr tuple(tuple&&) = default;
619 template<typename _U1, typename _U2, typename = typename
620 enable_if<__and_<is_convertible<const _U1&, _T1>,
621 is_convertible<const _U2&, _T2>>::value>::type>
622 constexpr tuple(const tuple<_U1, _U2>& __in)
623 : _Inherited(static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in)) { }
625 template<typename _U1, typename _U2, typename = typename
626 enable_if<__and_<is_convertible<_U1, _T1>,
627 is_convertible<_U2, _T2>>::value>::type>
628 constexpr tuple(tuple<_U1, _U2>&& __in)
629 : _Inherited(static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in)) { }
631 template<typename _U1, typename _U2, typename = typename
632 enable_if<__and_<is_convertible<const _U1&, _T1>,
633 is_convertible<const _U2&, _T2>>::value>::type>
634 constexpr tuple(const pair<_U1, _U2>& __in)
635 : _Inherited(__in.first, __in.second) { }
637 template<typename _U1, typename _U2, typename = typename
638 enable_if<__and_<is_convertible<_U1, _T1>,
639 is_convertible<_U2, _T2>>::value>::type>
640 constexpr tuple(pair<_U1, _U2>&& __in)
641 : _Inherited(std::forward<_U1>(__in.first),
642 std::forward<_U2>(__in.second)) { }
644 // Allocator-extended constructors.
646 template<typename _Alloc>
647 tuple(allocator_arg_t __tag, const _Alloc& __a)
648 : _Inherited(__tag, __a) { }
650 template<typename _Alloc>
651 tuple(allocator_arg_t __tag, const _Alloc& __a,
652 const _T1& __a1, const _T2& __a2)
653 : _Inherited(__tag, __a, __a1, __a2) { }
655 template<typename _Alloc, typename _U1, typename _U2>
656 tuple(allocator_arg_t __tag, const _Alloc& __a, _U1&& __a1, _U2&& __a2)
657 : _Inherited(__tag, __a, std::forward<_U1>(__a1),
658 std::forward<_U2>(__a2)) { }
660 template<typename _Alloc>
661 tuple(allocator_arg_t __tag, const _Alloc& __a, const tuple& __in)
662 : _Inherited(__tag, __a, static_cast<const _Inherited&>(__in)) { }
664 template<typename _Alloc>
665 tuple(allocator_arg_t __tag, const _Alloc& __a, tuple&& __in)
666 : _Inherited(__tag, __a, static_cast<_Inherited&&>(__in)) { }
668 template<typename _Alloc, typename _U1, typename _U2>
669 tuple(allocator_arg_t __tag, const _Alloc& __a,
670 const tuple<_U1, _U2>& __in)
671 : _Inherited(__tag, __a,
672 static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in))
675 template<typename _Alloc, typename _U1, typename _U2>
676 tuple(allocator_arg_t __tag, const _Alloc& __a, tuple<_U1, _U2>&& __in)
677 : _Inherited(__tag, __a, static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in))
680 template<typename _Alloc, typename _U1, typename _U2>
681 tuple(allocator_arg_t __tag, const _Alloc& __a,
682 const pair<_U1, _U2>& __in)
683 : _Inherited(__tag, __a, __in.first, __in.second) { }
685 template<typename _Alloc, typename _U1, typename _U2>
686 tuple(allocator_arg_t __tag, const _Alloc& __a, pair<_U1, _U2>&& __in)
687 : _Inherited(__tag, __a, std::forward<_U1>(__in.first),
688 std::forward<_U2>(__in.second)) { }
691 operator=(const tuple& __in)
693 static_cast<_Inherited&>(*this) = __in;
698 operator=(tuple&& __in)
699 noexcept(is_nothrow_move_assignable<_Inherited>::value)
701 static_cast<_Inherited&>(*this) = std::move(__in);
705 template<typename _U1, typename _U2>
707 operator=(const tuple<_U1, _U2>& __in)
709 static_cast<_Inherited&>(*this) = __in;
713 template<typename _U1, typename _U2>
715 operator=(tuple<_U1, _U2>&& __in)
717 static_cast<_Inherited&>(*this) = std::move(__in);
721 template<typename _U1, typename _U2>
723 operator=(const pair<_U1, _U2>& __in)
725 this->_M_head(*this) = __in.first;
726 this->_M_tail(*this)._M_head(*this) = __in.second;
730 template<typename _U1, typename _U2>
732 operator=(pair<_U1, _U2>&& __in)
734 this->_M_head(*this) = std::forward<_U1>(__in.first);
735 this->_M_tail(*this)._M_head(*this) = std::forward<_U2>(__in.second);
741 noexcept(noexcept(__in._M_swap(__in)))
742 { _Inherited::_M_swap(__in); }
746 /// Gives the type of the ith element of a given tuple type.
747 template<std::size_t __i, typename _Tp>
748 struct tuple_element;
751 * Recursive case for tuple_element: strip off the first element in
752 * the tuple and retrieve the (i-1)th element of the remaining tuple.
754 template<std::size_t __i, typename _Head, typename... _Tail>
755 struct tuple_element<__i, tuple<_Head, _Tail...> >
756 : tuple_element<__i - 1, tuple<_Tail...> > { };
759 * Basis case for tuple_element: The first element is the one we're seeking.
761 template<typename _Head, typename... _Tail>
762 struct tuple_element<0, tuple<_Head, _Tail...> >
767 // Duplicate of C++14's tuple_element_t for internal use in C++11 mode
768 template<std::size_t __i, typename _Tp>
769 using __tuple_element_t = typename tuple_element<__i, _Tp>::type;
771 template<std::size_t __i, typename _Tp>
772 struct tuple_element<__i, const _Tp>
774 typedef typename add_const<__tuple_element_t<__i, _Tp>>::type type;
777 template<std::size_t __i, typename _Tp>
778 struct tuple_element<__i, volatile _Tp>
780 typedef typename add_volatile<__tuple_element_t<__i, _Tp>>::type type;
783 template<std::size_t __i, typename _Tp>
784 struct tuple_element<__i, const volatile _Tp>
786 typedef typename add_cv<__tuple_element_t<__i, _Tp>>::type type;
789 #if __cplusplus > 201103L
790 #define __cpp_lib_tuple_element_t 201402
792 template<std::size_t __i, typename _Tp>
793 using tuple_element_t = typename tuple_element<__i, _Tp>::type;
796 /// Finds the size of a given tuple type.
797 template<typename _Tp>
800 // _GLIBCXX_RESOLVE_LIB_DEFECTS
801 // 2313. tuple_size should always derive from integral_constant<size_t, N>
802 template<typename _Tp>
803 struct tuple_size<const _Tp>
804 : integral_constant<size_t, tuple_size<_Tp>::value> { };
806 template<typename _Tp>
807 struct tuple_size<volatile _Tp>
808 : integral_constant<size_t, tuple_size<_Tp>::value> { };
810 template<typename _Tp>
811 struct tuple_size<const volatile _Tp>
812 : integral_constant<size_t, tuple_size<_Tp>::value> { };
815 template<typename... _Elements>
816 struct tuple_size<tuple<_Elements...>>
817 : public integral_constant<std::size_t, sizeof...(_Elements)> { };
819 template<std::size_t __i, typename _Head, typename... _Tail>
821 __get_helper(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
822 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
824 template<std::size_t __i, typename _Head, typename... _Tail>
825 constexpr const _Head&
826 __get_helper(const _Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
827 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
829 /// Return a reference to the ith element of a tuple.
830 template<std::size_t __i, typename... _Elements>
831 constexpr __tuple_element_t<__i, tuple<_Elements...>>&
832 get(tuple<_Elements...>& __t) noexcept
833 { return std::__get_helper<__i>(__t); }
835 /// Return a const reference to the ith element of a const tuple.
836 template<std::size_t __i, typename... _Elements>
837 constexpr const __tuple_element_t<__i, tuple<_Elements...>>&
838 get(const tuple<_Elements...>& __t) noexcept
839 { return std::__get_helper<__i>(__t); }
841 /// Return an rvalue reference to the ith element of a tuple rvalue.
842 template<std::size_t __i, typename... _Elements>
843 constexpr __tuple_element_t<__i, tuple<_Elements...>>&&
844 get(tuple<_Elements...>&& __t) noexcept
846 typedef __tuple_element_t<__i, tuple<_Elements...>> __element_type;
847 return std::forward<__element_type&&>(std::get<__i>(__t));
850 #if __cplusplus > 201103L
852 #define __cpp_lib_tuples_by_type 201304
854 template<typename _Head, size_t __i, typename... _Tail>
856 __get_helper2(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
857 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
859 template<typename _Head, size_t __i, typename... _Tail>
860 constexpr const _Head&
861 __get_helper2(const _Tuple_impl<__i, _Head, _Tail...>& __t) noexcept
862 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); }
864 /// Return a reference to the unique element of type _Tp of a tuple.
865 template <typename _Tp, typename... _Types>
867 get(tuple<_Types...>& __t) noexcept
868 { return std::__get_helper2<_Tp>(__t); }
870 /// Return a reference to the unique element of type _Tp of a tuple rvalue.
871 template <typename _Tp, typename... _Types>
873 get(tuple<_Types...>&& __t) noexcept
874 { return std::forward<_Tp&&>(std::__get_helper2<_Tp>(__t)); }
876 /// Return a const reference to the unique element of type _Tp of a tuple.
877 template <typename _Tp, typename... _Types>
879 get(const tuple<_Types...>& __t) noexcept
880 { return std::__get_helper2<_Tp>(__t); }
883 // This class performs the comparison operations on tuples
884 template<typename _Tp, typename _Up, size_t __i, size_t __size>
885 struct __tuple_compare
887 static constexpr bool
888 __eq(const _Tp& __t, const _Up& __u)
890 return bool(std::get<__i>(__t) == std::get<__i>(__u))
891 && __tuple_compare<_Tp, _Up, __i + 1, __size>::__eq(__t, __u);
894 static constexpr bool
895 __less(const _Tp& __t, const _Up& __u)
897 return bool(std::get<__i>(__t) < std::get<__i>(__u))
898 || (!bool(std::get<__i>(__u) < std::get<__i>(__t))
899 && __tuple_compare<_Tp, _Up, __i + 1, __size>::__less(__t, __u));
903 template<typename _Tp, typename _Up, size_t __size>
904 struct __tuple_compare<_Tp, _Up, __size, __size>
906 static constexpr bool
907 __eq(const _Tp&, const _Up&) { return true; }
909 static constexpr bool
910 __less(const _Tp&, const _Up&) { return false; }
913 template<typename... _TElements, typename... _UElements>
915 operator==(const tuple<_TElements...>& __t,
916 const tuple<_UElements...>& __u)
918 static_assert(sizeof...(_TElements) == sizeof...(_UElements),
919 "tuple objects can only be compared if they have equal sizes.");
920 using __compare = __tuple_compare<tuple<_TElements...>,
921 tuple<_UElements...>,
922 0, sizeof...(_TElements)>;
923 return __compare::__eq(__t, __u);
926 template<typename... _TElements, typename... _UElements>
928 operator<(const tuple<_TElements...>& __t,
929 const tuple<_UElements...>& __u)
931 static_assert(sizeof...(_TElements) == sizeof...(_UElements),
932 "tuple objects can only be compared if they have equal sizes.");
933 using __compare = __tuple_compare<tuple<_TElements...>,
934 tuple<_UElements...>,
935 0, sizeof...(_TElements)>;
936 return __compare::__less(__t, __u);
939 template<typename... _TElements, typename... _UElements>
941 operator!=(const tuple<_TElements...>& __t,
942 const tuple<_UElements...>& __u)
943 { return !(__t == __u); }
945 template<typename... _TElements, typename... _UElements>
947 operator>(const tuple<_TElements...>& __t,
948 const tuple<_UElements...>& __u)
949 { return __u < __t; }
951 template<typename... _TElements, typename... _UElements>
953 operator<=(const tuple<_TElements...>& __t,
954 const tuple<_UElements...>& __u)
955 { return !(__u < __t); }
957 template<typename... _TElements, typename... _UElements>
959 operator>=(const tuple<_TElements...>& __t,
960 const tuple<_UElements...>& __u)
961 { return !(__t < __u); }
964 template<typename... _Elements>
965 constexpr tuple<typename __decay_and_strip<_Elements>::__type...>
966 make_tuple(_Elements&&... __args)
968 typedef tuple<typename __decay_and_strip<_Elements>::__type...>
970 return __result_type(std::forward<_Elements>(__args)...);
973 template<typename... _Elements>
974 tuple<_Elements&&...>
975 forward_as_tuple(_Elements&&... __args) noexcept
976 { return tuple<_Elements&&...>(std::forward<_Elements>(__args)...); }
979 struct __is_tuple_like_impl : false_type
982 template<typename... _Tps>
983 struct __is_tuple_like_impl<tuple<_Tps...>> : true_type
986 template<typename _T1, typename _T2>
987 struct __is_tuple_like_impl<pair<_T1, _T2>> : true_type
990 template<typename _Tp, std::size_t _Nm>
991 struct __is_tuple_like_impl<array<_Tp, _Nm>> : true_type
994 // Internal type trait that allows us to sfinae-protect tuple_cat.
995 template<typename _Tp>
996 struct __is_tuple_like
997 : public __is_tuple_like_impl<typename std::remove_cv
998 <typename std::remove_reference<_Tp>::type>::type>::type
1001 template<size_t, typename, typename, size_t>
1002 struct __make_tuple_impl;
1004 template<size_t _Idx, typename _Tuple, typename... _Tp, size_t _Nm>
1005 struct __make_tuple_impl<_Idx, tuple<_Tp...>, _Tuple, _Nm>
1006 : __make_tuple_impl<_Idx + 1,
1007 tuple<_Tp..., __tuple_element_t<_Idx, _Tuple>>,
1011 template<std::size_t _Nm, typename _Tuple, typename... _Tp>
1012 struct __make_tuple_impl<_Nm, tuple<_Tp...>, _Tuple, _Nm>
1014 typedef tuple<_Tp...> __type;
1017 template<typename _Tuple>
1018 struct __do_make_tuple
1019 : __make_tuple_impl<0, tuple<>, _Tuple, std::tuple_size<_Tuple>::value>
1022 // Returns the std::tuple equivalent of a tuple-like type.
1023 template<typename _Tuple>
1025 : public __do_make_tuple<typename std::remove_cv
1026 <typename std::remove_reference<_Tuple>::type>::type>
1029 // Combines several std::tuple's into a single one.
1030 template<typename...>
1031 struct __combine_tuples;
1034 struct __combine_tuples<>
1036 typedef tuple<> __type;
1039 template<typename... _Ts>
1040 struct __combine_tuples<tuple<_Ts...>>
1042 typedef tuple<_Ts...> __type;
1045 template<typename... _T1s, typename... _T2s, typename... _Rem>
1046 struct __combine_tuples<tuple<_T1s...>, tuple<_T2s...>, _Rem...>
1048 typedef typename __combine_tuples<tuple<_T1s..., _T2s...>,
1049 _Rem...>::__type __type;
1052 // Computes the result type of tuple_cat given a set of tuple-like types.
1053 template<typename... _Tpls>
1054 struct __tuple_cat_result
1056 typedef typename __combine_tuples
1057 <typename __make_tuple<_Tpls>::__type...>::__type __type;
1060 // Helper to determine the index set for the first tuple-like
1061 // type of a given set.
1062 template<typename...>
1063 struct __make_1st_indices;
1066 struct __make_1st_indices<>
1068 typedef std::_Index_tuple<> __type;
1071 template<typename _Tp, typename... _Tpls>
1072 struct __make_1st_indices<_Tp, _Tpls...>
1074 typedef typename std::_Build_index_tuple<std::tuple_size<
1075 typename std::remove_reference<_Tp>::type>::value>::__type __type;
1078 // Performs the actual concatenation by step-wise expanding tuple-like
1079 // objects into the elements, which are finally forwarded into the
1081 template<typename _Ret, typename _Indices, typename... _Tpls>
1082 struct __tuple_concater;
1084 template<typename _Ret, std::size_t... _Is, typename _Tp, typename... _Tpls>
1085 struct __tuple_concater<_Ret, std::_Index_tuple<_Is...>, _Tp, _Tpls...>
1087 template<typename... _Us>
1088 static constexpr _Ret
1089 _S_do(_Tp&& __tp, _Tpls&&... __tps, _Us&&... __us)
1091 typedef typename __make_1st_indices<_Tpls...>::__type __idx;
1092 typedef __tuple_concater<_Ret, __idx, _Tpls...> __next;
1093 return __next::_S_do(std::forward<_Tpls>(__tps)...,
1094 std::forward<_Us>(__us)...,
1095 std::get<_Is>(std::forward<_Tp>(__tp))...);
1099 template<typename _Ret>
1100 struct __tuple_concater<_Ret, std::_Index_tuple<>>
1102 template<typename... _Us>
1103 static constexpr _Ret
1104 _S_do(_Us&&... __us)
1106 return _Ret(std::forward<_Us>(__us)...);
1111 template<typename... _Tpls, typename = typename
1112 enable_if<__and_<__is_tuple_like<_Tpls>...>::value>::type>
1114 tuple_cat(_Tpls&&... __tpls)
1115 -> typename __tuple_cat_result<_Tpls...>::__type
1117 typedef typename __tuple_cat_result<_Tpls...>::__type __ret;
1118 typedef typename __make_1st_indices<_Tpls...>::__type __idx;
1119 typedef __tuple_concater<__ret, __idx, _Tpls...> __concater;
1120 return __concater::_S_do(std::forward<_Tpls>(__tpls)...);
1124 template<typename... _Elements>
1125 inline tuple<_Elements&...>
1126 tie(_Elements&... __args) noexcept
1127 { return tuple<_Elements&...>(__args...); }
1130 template<typename... _Elements>
1132 swap(tuple<_Elements...>& __x, tuple<_Elements...>& __y)
1133 noexcept(noexcept(__x.swap(__y)))
1136 // A class (and instance) which can be used in 'tie' when an element
1137 // of a tuple is not required
1138 struct _Swallow_assign
1141 const _Swallow_assign&
1142 operator=(const _Tp&) const
1146 const _Swallow_assign ignore{};
1148 /// Partial specialization for tuples
1149 template<typename... _Types, typename _Alloc>
1150 struct uses_allocator<tuple<_Types...>, _Alloc> : true_type { };
1152 // See stl_pair.h...
1153 template<class _T1, class _T2>
1154 template<typename... _Args1, typename... _Args2>
1157 pair(piecewise_construct_t,
1158 tuple<_Args1...> __first, tuple<_Args2...> __second)
1159 : pair(__first, __second,
1160 typename _Build_index_tuple<sizeof...(_Args1)>::__type(),
1161 typename _Build_index_tuple<sizeof...(_Args2)>::__type())
1164 template<class _T1, class _T2>
1165 template<typename... _Args1, std::size_t... _Indexes1,
1166 typename... _Args2, std::size_t... _Indexes2>
1169 pair(tuple<_Args1...>& __tuple1, tuple<_Args2...>& __tuple2,
1170 _Index_tuple<_Indexes1...>, _Index_tuple<_Indexes2...>)
1171 : first(std::forward<_Args1>(std::get<_Indexes1>(__tuple1))...),
1172 second(std::forward<_Args2>(std::get<_Indexes2>(__tuple2))...)
1177 _GLIBCXX_END_NAMESPACE_VERSION
1182 #endif // _GLIBCXX_TUPLE