tuple revision 1.1.1.5.8.1
1 // <tuple> -*- C++ -*- 2 3 // Copyright (C) 2007-2015 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 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 42 namespace 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(noexcept(swap(std::declval<_Head&>(), 328 std::declval<_Head&>())) 329 && noexcept(_M_tail(__in)._M_swap(_M_tail(__in)))) 330 { 331 using std::swap; 332 swap(_M_head(*this), _M_head(__in)); 333 _Inherited::_M_swap(_M_tail(__in)); 334 } 335 }; 336 337 // 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> 341 { 342 template<std::size_t, typename...> friend class _Tuple_impl; 343 344 typedef _Head_base<_Idx, _Head, __empty_not_final<_Head>::value> _Base; 345 346 static constexpr _Head& 347 _M_head(_Tuple_impl& __t) noexcept { return _Base::_M_head(__t); } 348 349 static constexpr const _Head& 350 _M_head(const _Tuple_impl& __t) noexcept { return _Base::_M_head(__t); } 351 352 constexpr _Tuple_impl() 353 : _Base() { } 354 355 explicit 356 constexpr _Tuple_impl(const _Head& __head) 357 : _Base(__head) { } 358 359 template<typename _UHead> 360 explicit 361 constexpr _Tuple_impl(_UHead&& __head) 362 : _Base(std::forward<_UHead>(__head)) { } 363 364 constexpr _Tuple_impl(const _Tuple_impl&) = default; 365 366 constexpr 367 _Tuple_impl(_Tuple_impl&& __in) 368 noexcept(is_nothrow_move_constructible<_Head>::value) 369 : _Base(std::forward<_Head>(_M_head(__in))) { } 370 371 template<typename _UHead> 372 constexpr _Tuple_impl(const _Tuple_impl<_Idx, _UHead>& __in) 373 : _Base(_Tuple_impl<_Idx, _UHead>::_M_head(__in)) { } 374 375 template<typename _UHead> 376 constexpr _Tuple_impl(_Tuple_impl<_Idx, _UHead>&& __in) 377 : _Base(std::forward<_UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in))) 378 { } 379 380 template<typename _Alloc> 381 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a) 382 : _Base(__tag, __use_alloc<_Head>(__a)) { } 383 384 template<typename _Alloc> 385 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a, 386 const _Head& __head) 387 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a), __head) { } 388 389 template<typename _Alloc, typename _UHead> 390 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a, 391 _UHead&& __head) 392 : _Base(__use_alloc<_Head, _Alloc, _UHead>(__a), 393 std::forward<_UHead>(__head)) { } 394 395 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)) { } 399 400 template<typename _Alloc> 401 _Tuple_impl(allocator_arg_t __tag, const _Alloc& __a, 402 _Tuple_impl&& __in) 403 : _Base(__use_alloc<_Head, _Alloc, _Head>(__a), 404 std::forward<_Head>(_M_head(__in))) { } 405 406 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)) { } 411 412 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))) 417 { } 418 419 _Tuple_impl& 420 operator=(const _Tuple_impl& __in) 421 { 422 _M_head(*this) = _M_head(__in); 423 return *this; 424 } 425 426 _Tuple_impl& 427 operator=(_Tuple_impl&& __in) 428 noexcept(is_nothrow_move_assignable<_Head>::value) 429 { 430 _M_head(*this) = std::forward<_Head>(_M_head(__in)); 431 return *this; 432 } 433 434 template<typename _UHead> 435 _Tuple_impl& 436 operator=(const _Tuple_impl<_Idx, _UHead>& __in) 437 { 438 _M_head(*this) = _Tuple_impl<_Idx, _UHead>::_M_head(__in); 439 return *this; 440 } 441 442 template<typename _UHead> 443 _Tuple_impl& 444 operator=(_Tuple_impl<_Idx, _UHead>&& __in) 445 { 446 _M_head(*this) 447 = std::forward<_UHead>(_Tuple_impl<_Idx, _UHead>::_M_head(__in)); 448 return *this; 449 } 450 451 protected: 452 void 453 _M_swap(_Tuple_impl& __in) 454 noexcept(noexcept(swap(std::declval<_Head&>(), std::declval<_Head&>()))) 455 { 456 using std::swap; 457 swap(_M_head(*this), _M_head(__in)); 458 } 459 }; 460 461 /// Primary class template, tuple 462 template<typename... _Elements> 463 class tuple : public _Tuple_impl<0, _Elements...> 464 { 465 typedef _Tuple_impl<0, _Elements...> _Inherited; 466 467 public: 468 constexpr tuple() 469 : _Inherited() { } 470 471 explicit 472 constexpr tuple(const _Elements&... __elements) 473 : _Inherited(__elements...) { } 474 475 template<typename... _UElements, typename = typename 476 enable_if<__and_<is_convertible<_UElements, 477 _Elements>...>::value>::type> 478 explicit 479 constexpr tuple(_UElements&&... __elements) 480 : _Inherited(std::forward<_UElements>(__elements)...) { } 481 482 constexpr tuple(const tuple&) = default; 483 484 constexpr tuple(tuple&&) = default; 485 486 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)) 491 { } 492 493 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)) { } 498 499 // Allocator-extended constructors. 500 501 template<typename _Alloc> 502 tuple(allocator_arg_t __tag, const _Alloc& __a) 503 : _Inherited(__tag, __a) { } 504 505 template<typename _Alloc> 506 tuple(allocator_arg_t __tag, const _Alloc& __a, 507 const _Elements&... __elements) 508 : _Inherited(__tag, __a, __elements...) { } 509 510 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)...) 516 { } 517 518 template<typename _Alloc> 519 tuple(allocator_arg_t __tag, const _Alloc& __a, const tuple& __in) 520 : _Inherited(__tag, __a, static_cast<const _Inherited&>(__in)) { } 521 522 template<typename _Alloc> 523 tuple(allocator_arg_t __tag, const _Alloc& __a, tuple&& __in) 524 : _Inherited(__tag, __a, static_cast<_Inherited&&>(__in)) { } 525 526 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)) 533 { } 534 535 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)) 542 { } 543 544 tuple& 545 operator=(const tuple& __in) 546 { 547 static_cast<_Inherited&>(*this) = __in; 548 return *this; 549 } 550 551 tuple& 552 operator=(tuple&& __in) 553 noexcept(is_nothrow_move_assignable<_Inherited>::value) 554 { 555 static_cast<_Inherited&>(*this) = std::move(__in); 556 return *this; 557 } 558 559 template<typename... _UElements, typename = typename 560 enable_if<sizeof...(_UElements) 561 == sizeof...(_Elements)>::type> 562 tuple& 563 operator=(const tuple<_UElements...>& __in) 564 { 565 static_cast<_Inherited&>(*this) = __in; 566 return *this; 567 } 568 569 template<typename... _UElements, typename = typename 570 enable_if<sizeof...(_UElements) 571 == sizeof...(_Elements)>::type> 572 tuple& 573 operator=(tuple<_UElements...>&& __in) 574 { 575 static_cast<_Inherited&>(*this) = std::move(__in); 576 return *this; 577 } 578 579 void 580 swap(tuple& __in) 581 noexcept(noexcept(__in._M_swap(__in))) 582 { _Inherited::_M_swap(__in); } 583 }; 584 585 // Explicit specialization, zero-element tuple. 586 template<> 587 class tuple<> 588 { 589 public: 590 void swap(tuple&) noexcept { /* no-op */ } 591 }; 592 593 /// 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> 597 { 598 typedef _Tuple_impl<0, _T1, _T2> _Inherited; 599 600 public: 601 constexpr tuple() 602 : _Inherited() { } 603 604 explicit 605 constexpr tuple(const _T1& __a1, const _T2& __a2) 606 : _Inherited(__a1, __a2) { } 607 608 template<typename _U1, typename _U2, typename = typename 609 enable_if<__and_<is_convertible<_U1, _T1>, 610 is_convertible<_U2, _T2>, 611 __not_<is_same<typename decay<_U1>::type, 612 allocator_arg_t>>> 613 ::value>::type> 614 explicit 615 constexpr tuple(_U1&& __a1, _U2&& __a2) 616 : _Inherited(std::forward<_U1>(__a1), std::forward<_U2>(__a2)) { } 617 618 constexpr tuple(const tuple&) = default; 619 620 constexpr tuple(tuple&&) = default; 621 622 template<typename _U1, typename _U2, typename = typename 623 enable_if<__and_<is_convertible<const _U1&, _T1>, 624 is_convertible<const _U2&, _T2>>::value>::type> 625 constexpr tuple(const tuple<_U1, _U2>& __in) 626 : _Inherited(static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in)) { } 627 628 template<typename _U1, typename _U2, typename = typename 629 enable_if<__and_<is_convertible<_U1, _T1>, 630 is_convertible<_U2, _T2>>::value>::type> 631 constexpr tuple(tuple<_U1, _U2>&& __in) 632 : _Inherited(static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in)) { } 633 634 template<typename _U1, typename _U2, typename = typename 635 enable_if<__and_<is_convertible<const _U1&, _T1>, 636 is_convertible<const _U2&, _T2>>::value>::type> 637 constexpr tuple(const pair<_U1, _U2>& __in) 638 : _Inherited(__in.first, __in.second) { } 639 640 template<typename _U1, typename _U2, typename = typename 641 enable_if<__and_<is_convertible<_U1, _T1>, 642 is_convertible<_U2, _T2>>::value>::type> 643 constexpr tuple(pair<_U1, _U2>&& __in) 644 : _Inherited(std::forward<_U1>(__in.first), 645 std::forward<_U2>(__in.second)) { } 646 647 // Allocator-extended constructors. 648 649 template<typename _Alloc> 650 tuple(allocator_arg_t __tag, const _Alloc& __a) 651 : _Inherited(__tag, __a) { } 652 653 template<typename _Alloc> 654 tuple(allocator_arg_t __tag, const _Alloc& __a, 655 const _T1& __a1, const _T2& __a2) 656 : _Inherited(__tag, __a, __a1, __a2) { } 657 658 template<typename _Alloc, typename _U1, typename _U2> 659 tuple(allocator_arg_t __tag, const _Alloc& __a, _U1&& __a1, _U2&& __a2) 660 : _Inherited(__tag, __a, std::forward<_U1>(__a1), 661 std::forward<_U2>(__a2)) { } 662 663 template<typename _Alloc> 664 tuple(allocator_arg_t __tag, const _Alloc& __a, const tuple& __in) 665 : _Inherited(__tag, __a, static_cast<const _Inherited&>(__in)) { } 666 667 template<typename _Alloc> 668 tuple(allocator_arg_t __tag, const _Alloc& __a, tuple&& __in) 669 : _Inherited(__tag, __a, static_cast<_Inherited&&>(__in)) { } 670 671 template<typename _Alloc, typename _U1, typename _U2> 672 tuple(allocator_arg_t __tag, const _Alloc& __a, 673 const tuple<_U1, _U2>& __in) 674 : _Inherited(__tag, __a, 675 static_cast<const _Tuple_impl<0, _U1, _U2>&>(__in)) 676 { } 677 678 template<typename _Alloc, typename _U1, typename _U2> 679 tuple(allocator_arg_t __tag, const _Alloc& __a, tuple<_U1, _U2>&& __in) 680 : _Inherited(__tag, __a, static_cast<_Tuple_impl<0, _U1, _U2>&&>(__in)) 681 { } 682 683 template<typename _Alloc, typename _U1, typename _U2> 684 tuple(allocator_arg_t __tag, const _Alloc& __a, 685 const pair<_U1, _U2>& __in) 686 : _Inherited(__tag, __a, __in.first, __in.second) { } 687 688 template<typename _Alloc, typename _U1, typename _U2> 689 tuple(allocator_arg_t __tag, const _Alloc& __a, pair<_U1, _U2>&& __in) 690 : _Inherited(__tag, __a, std::forward<_U1>(__in.first), 691 std::forward<_U2>(__in.second)) { } 692 693 tuple& 694 operator=(const tuple& __in) 695 { 696 static_cast<_Inherited&>(*this) = __in; 697 return *this; 698 } 699 700 tuple& 701 operator=(tuple&& __in) 702 noexcept(is_nothrow_move_assignable<_Inherited>::value) 703 { 704 static_cast<_Inherited&>(*this) = std::move(__in); 705 return *this; 706 } 707 708 template<typename _U1, typename _U2> 709 tuple& 710 operator=(const tuple<_U1, _U2>& __in) 711 { 712 static_cast<_Inherited&>(*this) = __in; 713 return *this; 714 } 715 716 template<typename _U1, typename _U2> 717 tuple& 718 operator=(tuple<_U1, _U2>&& __in) 719 { 720 static_cast<_Inherited&>(*this) = std::move(__in); 721 return *this; 722 } 723 724 template<typename _U1, typename _U2> 725 tuple& 726 operator=(const pair<_U1, _U2>& __in) 727 { 728 this->_M_head(*this) = __in.first; 729 this->_M_tail(*this)._M_head(*this) = __in.second; 730 return *this; 731 } 732 733 template<typename _U1, typename _U2> 734 tuple& 735 operator=(pair<_U1, _U2>&& __in) 736 { 737 this->_M_head(*this) = std::forward<_U1>(__in.first); 738 this->_M_tail(*this)._M_head(*this) = std::forward<_U2>(__in.second); 739 return *this; 740 } 741 742 void 743 swap(tuple& __in) 744 noexcept(noexcept(__in._M_swap(__in))) 745 { _Inherited::_M_swap(__in); } 746 }; 747 748 749 /// Gives the type of the ith element of a given tuple type. 750 template<std::size_t __i, typename _Tp> 751 struct tuple_element; 752 753 /** 754 * Recursive case for tuple_element: strip off the first element in 755 * the tuple and retrieve the (i-1)th element of the remaining tuple. 756 */ 757 template<std::size_t __i, typename _Head, typename... _Tail> 758 struct tuple_element<__i, tuple<_Head, _Tail...> > 759 : tuple_element<__i - 1, tuple<_Tail...> > { }; 760 761 /** 762 * Basis case for tuple_element: The first element is the one we're seeking. 763 */ 764 template<typename _Head, typename... _Tail> 765 struct tuple_element<0, tuple<_Head, _Tail...> > 766 { 767 typedef _Head type; 768 }; 769 770 // Duplicate of C++14's tuple_element_t for internal use in C++11 mode 771 template<std::size_t __i, typename _Tp> 772 using __tuple_element_t = typename tuple_element<__i, _Tp>::type; 773 774 template<std::size_t __i, typename _Tp> 775 struct tuple_element<__i, const _Tp> 776 { 777 typedef typename add_const<__tuple_element_t<__i, _Tp>>::type type; 778 }; 779 780 template<std::size_t __i, typename _Tp> 781 struct tuple_element<__i, volatile _Tp> 782 { 783 typedef typename add_volatile<__tuple_element_t<__i, _Tp>>::type type; 784 }; 785 786 template<std::size_t __i, typename _Tp> 787 struct tuple_element<__i, const volatile _Tp> 788 { 789 typedef typename add_cv<__tuple_element_t<__i, _Tp>>::type type; 790 }; 791 792 #if __cplusplus > 201103L 793 #define __cpp_lib_tuple_element_t 201402 794 795 template<std::size_t __i, typename _Tp> 796 using tuple_element_t = typename tuple_element<__i, _Tp>::type; 797 #endif 798 799 /// Finds the size of a given tuple type. 800 template<typename _Tp> 801 struct tuple_size; 802 803 // _GLIBCXX_RESOLVE_LIB_DEFECTS 804 // 2313. tuple_size should always derive from integral_constant<size_t, N> 805 template<typename _Tp> 806 struct tuple_size<const _Tp> 807 : integral_constant<size_t, tuple_size<_Tp>::value> { }; 808 809 template<typename _Tp> 810 struct tuple_size<volatile _Tp> 811 : integral_constant<size_t, tuple_size<_Tp>::value> { }; 812 813 template<typename _Tp> 814 struct tuple_size<const volatile _Tp> 815 : integral_constant<size_t, tuple_size<_Tp>::value> { }; 816 817 /// class tuple_size 818 template<typename... _Elements> 819 struct tuple_size<tuple<_Elements...>> 820 : public integral_constant<std::size_t, sizeof...(_Elements)> { }; 821 822 template<std::size_t __i, typename _Head, typename... _Tail> 823 constexpr _Head& 824 __get_helper(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept 825 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); } 826 827 template<std::size_t __i, typename _Head, typename... _Tail> 828 constexpr const _Head& 829 __get_helper(const _Tuple_impl<__i, _Head, _Tail...>& __t) noexcept 830 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); } 831 832 /// Return a reference to the ith element of a tuple. 833 template<std::size_t __i, typename... _Elements> 834 constexpr __tuple_element_t<__i, tuple<_Elements...>>& 835 get(tuple<_Elements...>& __t) noexcept 836 { return std::__get_helper<__i>(__t); } 837 838 /// Return a const reference to the ith element of a const tuple. 839 template<std::size_t __i, typename... _Elements> 840 constexpr const __tuple_element_t<__i, tuple<_Elements...>>& 841 get(const tuple<_Elements...>& __t) noexcept 842 { return std::__get_helper<__i>(__t); } 843 844 /// Return an rvalue reference to the ith element of a tuple rvalue. 845 template<std::size_t __i, typename... _Elements> 846 constexpr __tuple_element_t<__i, tuple<_Elements...>>&& 847 get(tuple<_Elements...>&& __t) noexcept 848 { 849 typedef __tuple_element_t<__i, tuple<_Elements...>> __element_type; 850 return std::forward<__element_type&&>(std::get<__i>(__t)); 851 } 852 853 #if __cplusplus > 201103L 854 855 #define __cpp_lib_tuples_by_type 201304 856 857 template<typename _Head, size_t __i, typename... _Tail> 858 constexpr _Head& 859 __get_helper2(_Tuple_impl<__i, _Head, _Tail...>& __t) noexcept 860 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); } 861 862 template<typename _Head, size_t __i, typename... _Tail> 863 constexpr const _Head& 864 __get_helper2(const _Tuple_impl<__i, _Head, _Tail...>& __t) noexcept 865 { return _Tuple_impl<__i, _Head, _Tail...>::_M_head(__t); } 866 867 /// Return a reference to the unique element of type _Tp of a tuple. 868 template <typename _Tp, typename... _Types> 869 constexpr _Tp& 870 get(tuple<_Types...>& __t) noexcept 871 { return std::__get_helper2<_Tp>(__t); } 872 873 /// Return a reference to the unique element of type _Tp of a tuple rvalue. 874 template <typename _Tp, typename... _Types> 875 constexpr _Tp&& 876 get(tuple<_Types...>&& __t) noexcept 877 { return std::forward<_Tp&&>(std::__get_helper2<_Tp>(__t)); } 878 879 /// Return a const reference to the unique element of type _Tp of a tuple. 880 template <typename _Tp, typename... _Types> 881 constexpr const _Tp& 882 get(const tuple<_Types...>& __t) noexcept 883 { return std::__get_helper2<_Tp>(__t); } 884 #endif 885 886 // This class performs the comparison operations on tuples 887 template<typename _Tp, typename _Up, size_t __i, size_t __size> 888 struct __tuple_compare 889 { 890 static constexpr bool 891 __eq(const _Tp& __t, const _Up& __u) 892 { 893 return bool(std::get<__i>(__t) == std::get<__i>(__u)) 894 && __tuple_compare<_Tp, _Up, __i + 1, __size>::__eq(__t, __u); 895 } 896 897 static constexpr bool 898 __less(const _Tp& __t, const _Up& __u) 899 { 900 return bool(std::get<__i>(__t) < std::get<__i>(__u)) 901 || (!bool(std::get<__i>(__u) < std::get<__i>(__t)) 902 && __tuple_compare<_Tp, _Up, __i + 1, __size>::__less(__t, __u)); 903 } 904 }; 905 906 template<typename _Tp, typename _Up, size_t __size> 907 struct __tuple_compare<_Tp, _Up, __size, __size> 908 { 909 static constexpr bool 910 __eq(const _Tp&, const _Up&) { return true; } 911 912 static constexpr bool 913 __less(const _Tp&, const _Up&) { return false; } 914 }; 915 916 template<typename... _TElements, typename... _UElements> 917 constexpr bool 918 operator==(const tuple<_TElements...>& __t, 919 const tuple<_UElements...>& __u) 920 { 921 static_assert(sizeof...(_TElements) == sizeof...(_UElements), 922 "tuple objects can only be compared if they have equal sizes."); 923 using __compare = __tuple_compare<tuple<_TElements...>, 924 tuple<_UElements...>, 925 0, sizeof...(_TElements)>; 926 return __compare::__eq(__t, __u); 927 } 928 929 template<typename... _TElements, typename... _UElements> 930 constexpr bool 931 operator<(const tuple<_TElements...>& __t, 932 const tuple<_UElements...>& __u) 933 { 934 static_assert(sizeof...(_TElements) == sizeof...(_UElements), 935 "tuple objects can only be compared if they have equal sizes."); 936 using __compare = __tuple_compare<tuple<_TElements...>, 937 tuple<_UElements...>, 938 0, sizeof...(_TElements)>; 939 return __compare::__less(__t, __u); 940 } 941 942 template<typename... _TElements, typename... _UElements> 943 constexpr bool 944 operator!=(const tuple<_TElements...>& __t, 945 const tuple<_UElements...>& __u) 946 { return !(__t == __u); } 947 948 template<typename... _TElements, typename... _UElements> 949 constexpr bool 950 operator>(const tuple<_TElements...>& __t, 951 const tuple<_UElements...>& __u) 952 { return __u < __t; } 953 954 template<typename... _TElements, typename... _UElements> 955 constexpr bool 956 operator<=(const tuple<_TElements...>& __t, 957 const tuple<_UElements...>& __u) 958 { return !(__u < __t); } 959 960 template<typename... _TElements, typename... _UElements> 961 constexpr bool 962 operator>=(const tuple<_TElements...>& __t, 963 const tuple<_UElements...>& __u) 964 { return !(__t < __u); } 965 966 // NB: DR 705. 967 template<typename... _Elements> 968 constexpr tuple<typename __decay_and_strip<_Elements>::__type...> 969 make_tuple(_Elements&&... __args) 970 { 971 typedef tuple<typename __decay_and_strip<_Elements>::__type...> 972 __result_type; 973 return __result_type(std::forward<_Elements>(__args)...); 974 } 975 976 template<typename... _Elements> 977 tuple<_Elements&&...> 978 forward_as_tuple(_Elements&&... __args) noexcept 979 { return tuple<_Elements&&...>(std::forward<_Elements>(__args)...); } 980 981 template<typename> 982 struct __is_tuple_like_impl : false_type 983 { }; 984 985 template<typename... _Tps> 986 struct __is_tuple_like_impl<tuple<_Tps...>> : true_type 987 { }; 988 989 template<typename _T1, typename _T2> 990 struct __is_tuple_like_impl<pair<_T1, _T2>> : true_type 991 { }; 992 993 template<typename _Tp, std::size_t _Nm> 994 struct __is_tuple_like_impl<array<_Tp, _Nm>> : true_type 995 { }; 996 997 // Internal type trait that allows us to sfinae-protect tuple_cat. 998 template<typename _Tp> 999 struct __is_tuple_like 1000 : public __is_tuple_like_impl<typename std::remove_cv 1001 <typename std::remove_reference<_Tp>::type>::type>::type 1002 { }; 1003 1004 template<size_t, typename, typename, size_t> 1005 struct __make_tuple_impl; 1006 1007 template<size_t _Idx, typename _Tuple, typename... _Tp, size_t _Nm> 1008 struct __make_tuple_impl<_Idx, tuple<_Tp...>, _Tuple, _Nm> 1009 : __make_tuple_impl<_Idx + 1, 1010 tuple<_Tp..., __tuple_element_t<_Idx, _Tuple>>, 1011 _Tuple, _Nm> 1012 { }; 1013 1014 template<std::size_t _Nm, typename _Tuple, typename... _Tp> 1015 struct __make_tuple_impl<_Nm, tuple<_Tp...>, _Tuple, _Nm> 1016 { 1017 typedef tuple<_Tp...> __type; 1018 }; 1019 1020 template<typename _Tuple> 1021 struct __do_make_tuple 1022 : __make_tuple_impl<0, tuple<>, _Tuple, std::tuple_size<_Tuple>::value> 1023 { }; 1024 1025 // Returns the std::tuple equivalent of a tuple-like type. 1026 template<typename _Tuple> 1027 struct __make_tuple 1028 : public __do_make_tuple<typename std::remove_cv 1029 <typename std::remove_reference<_Tuple>::type>::type> 1030 { }; 1031 1032 // Combines several std::tuple's into a single one. 1033 template<typename...> 1034 struct __combine_tuples; 1035 1036 template<> 1037 struct __combine_tuples<> 1038 { 1039 typedef tuple<> __type; 1040 }; 1041 1042 template<typename... _Ts> 1043 struct __combine_tuples<tuple<_Ts...>> 1044 { 1045 typedef tuple<_Ts...> __type; 1046 }; 1047 1048 template<typename... _T1s, typename... _T2s, typename... _Rem> 1049 struct __combine_tuples<tuple<_T1s...>, tuple<_T2s...>, _Rem...> 1050 { 1051 typedef typename __combine_tuples<tuple<_T1s..., _T2s...>, 1052 _Rem...>::__type __type; 1053 }; 1054 1055 // Computes the result type of tuple_cat given a set of tuple-like types. 1056 template<typename... _Tpls> 1057 struct __tuple_cat_result 1058 { 1059 typedef typename __combine_tuples 1060 <typename __make_tuple<_Tpls>::__type...>::__type __type; 1061 }; 1062 1063 // Helper to determine the index set for the first tuple-like 1064 // type of a given set. 1065 template<typename...> 1066 struct __make_1st_indices; 1067 1068 template<> 1069 struct __make_1st_indices<> 1070 { 1071 typedef std::_Index_tuple<> __type; 1072 }; 1073 1074 template<typename _Tp, typename... _Tpls> 1075 struct __make_1st_indices<_Tp, _Tpls...> 1076 { 1077 typedef typename std::_Build_index_tuple<std::tuple_size< 1078 typename std::remove_reference<_Tp>::type>::value>::__type __type; 1079 }; 1080 1081 // Performs the actual concatenation by step-wise expanding tuple-like 1082 // objects into the elements, which are finally forwarded into the 1083 // result tuple. 1084 template<typename _Ret, typename _Indices, typename... _Tpls> 1085 struct __tuple_concater; 1086 1087 template<typename _Ret, std::size_t... _Is, typename _Tp, typename... _Tpls> 1088 struct __tuple_concater<_Ret, std::_Index_tuple<_Is...>, _Tp, _Tpls...> 1089 { 1090 template<typename... _Us> 1091 static constexpr _Ret 1092 _S_do(_Tp&& __tp, _Tpls&&... __tps, _Us&&... __us) 1093 { 1094 typedef typename __make_1st_indices<_Tpls...>::__type __idx; 1095 typedef __tuple_concater<_Ret, __idx, _Tpls...> __next; 1096 return __next::_S_do(std::forward<_Tpls>(__tps)..., 1097 std::forward<_Us>(__us)..., 1098 std::get<_Is>(std::forward<_Tp>(__tp))...); 1099 } 1100 }; 1101 1102 template<typename _Ret> 1103 struct __tuple_concater<_Ret, std::_Index_tuple<>> 1104 { 1105 template<typename... _Us> 1106 static constexpr _Ret 1107 _S_do(_Us&&... __us) 1108 { 1109 return _Ret(std::forward<_Us>(__us)...); 1110 } 1111 }; 1112 1113 /// tuple_cat 1114 template<typename... _Tpls, typename = typename 1115 enable_if<__and_<__is_tuple_like<_Tpls>...>::value>::type> 1116 constexpr auto 1117 tuple_cat(_Tpls&&... __tpls) 1118 -> typename __tuple_cat_result<_Tpls...>::__type 1119 { 1120 typedef typename __tuple_cat_result<_Tpls...>::__type __ret; 1121 typedef typename __make_1st_indices<_Tpls...>::__type __idx; 1122 typedef __tuple_concater<__ret, __idx, _Tpls...> __concater; 1123 return __concater::_S_do(std::forward<_Tpls>(__tpls)...); 1124 } 1125 1126 /// tie 1127 template<typename... _Elements> 1128 inline tuple<_Elements&...> 1129 tie(_Elements&... __args) noexcept 1130 { return tuple<_Elements&...>(__args...); } 1131 1132 /// swap 1133 template<typename... _Elements> 1134 inline void 1135 swap(tuple<_Elements...>& __x, tuple<_Elements...>& __y) 1136 noexcept(noexcept(__x.swap(__y))) 1137 { __x.swap(__y); } 1138 1139 // A class (and instance) which can be used in 'tie' when an element 1140 // of a tuple is not required 1141 struct _Swallow_assign 1142 { 1143 template<class _Tp> 1144 const _Swallow_assign& 1145 operator=(const _Tp&) const 1146 { return *this; } 1147 }; 1148 1149 const _Swallow_assign ignore{}; 1150 1151 /// Partial specialization for tuples 1152 template<typename... _Types, typename _Alloc> 1153 struct uses_allocator<tuple<_Types...>, _Alloc> : true_type { }; 1154 1155 // See stl_pair.h... 1156 template<class _T1, class _T2> 1157 template<typename... _Args1, typename... _Args2> 1158 inline 1159 pair<_T1, _T2>:: 1160 pair(piecewise_construct_t, 1161 tuple<_Args1...> __first, tuple<_Args2...> __second) 1162 : pair(__first, __second, 1163 typename _Build_index_tuple<sizeof...(_Args1)>::__type(), 1164 typename _Build_index_tuple<sizeof...(_Args2)>::__type()) 1165 { } 1166 1167 template<class _T1, class _T2> 1168 template<typename... _Args1, std::size_t... _Indexes1, 1169 typename... _Args2, std::size_t... _Indexes2> 1170 inline 1171 pair<_T1, _T2>:: 1172 pair(tuple<_Args1...>& __tuple1, tuple<_Args2...>& __tuple2, 1173 _Index_tuple<_Indexes1...>, _Index_tuple<_Indexes2...>) 1174 : first(std::forward<_Args1>(std::get<_Indexes1>(__tuple1))...), 1175 second(std::forward<_Args2>(std::get<_Indexes2>(__tuple2))...) 1176 { } 1177 1178 /// @} 1179 1180 _GLIBCXX_END_NAMESPACE_VERSION 1181 } // namespace std 1182 1183 #endif // C++11 1184 1185 #endif // _GLIBCXX_TUPLE 1186
Indexes created Sun Oct 25 00:26:45 UTC 2026