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1// -*- C++ -*-2//===----------------------------------------------------------------------===//3//4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.5// See https://llvm.org/LICENSE.txt for license information.6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception7//8//===----------------------------------------------------------------------===//9 10#ifndef _LIBCPP_TUPLE11#define _LIBCPP_TUPLE12 13// clang-format off14 15/*16 tuple synopsis17 18namespace std19{20 21template <class... T>22class tuple {23public:24 explicit(see-below) constexpr tuple();25 explicit(see-below) tuple(const T&...); // constexpr in C++1426 template <class... U>27 explicit(see-below) tuple(U&&...); // constexpr in C++1428 tuple(const tuple&) = default;29 tuple(tuple&&) = default;30 31 template<class... UTypes>32 constexpr explicit(see-below) tuple(tuple<UTypes...>&); // C++2333 template <class... U>34 explicit(see-below) tuple(const tuple<U...>&); // constexpr in C++1435 template <class... U>36 explicit(see-below) tuple(tuple<U...>&&); // constexpr in C++1437 template<class... UTypes>38 constexpr explicit(see-below) tuple(const tuple<UTypes...>&&); // C++2339 40 template<class U1, class U2>41 constexpr explicit(see-below) tuple(pair<U1, U2>&); // iff sizeof...(Types) == 2 // C++2342 template <class U1, class U2>43 explicit(see-below) tuple(const pair<U1, U2>&); // iff sizeof...(T) == 2 // constexpr in C++1444 template <class U1, class U2>45 explicit(see-below) tuple(pair<U1, U2>&&); // iff sizeof...(T) == 2 // constexpr in C++1446 template<class U1, class U2>47 constexpr explicit(see-below) tuple(const pair<U1, U2>&&); // iff sizeof...(Types) == 2 // C++2348 49 // allocator-extended constructors50 template <class Alloc>51 tuple(allocator_arg_t, const Alloc& a);52 template <class Alloc>53 explicit(see-below) tuple(allocator_arg_t, const Alloc& a, const T&...); // constexpr in C++2054 template <class Alloc, class... U>55 explicit(see-below) tuple(allocator_arg_t, const Alloc& a, U&&...); // constexpr in C++2056 template <class Alloc>57 tuple(allocator_arg_t, const Alloc& a, const tuple&); // constexpr in C++2058 template <class Alloc>59 tuple(allocator_arg_t, const Alloc& a, tuple&&); // constexpr in C++2060 template<class Alloc, class... UTypes>61 constexpr explicit(see-below)62 tuple(allocator_arg_t, const Alloc& a, tuple<UTypes...>&); // C++2363 template <class Alloc, class... U>64 explicit(see-below) tuple(allocator_arg_t, const Alloc& a, const tuple<U...>&); // constexpr in C++2065 template <class Alloc, class... U>66 explicit(see-below) tuple(allocator_arg_t, const Alloc& a, tuple<U...>&&); // constexpr in C++2067 template<class Alloc, class... UTypes>68 constexpr explicit(see-below)69 tuple(allocator_arg_t, const Alloc& a, const tuple<UTypes...>&&); // C++2370 template<class Alloc, class U1, class U2>71 constexpr explicit(see-below)72 tuple(allocator_arg_t, const Alloc& a, pair<U1, U2>&); // C++2373 template <class Alloc, class U1, class U2>74 explicit(see-below) tuple(allocator_arg_t, const Alloc& a, const pair<U1, U2>&); // constexpr in C++2075 template <class Alloc, class U1, class U2>76 explicit(see-below) tuple(allocator_arg_t, const Alloc& a, pair<U1, U2>&&); // constexpr in C++2077 template<class Alloc, class U1, class U2>78 constexpr explicit(see-below)79 tuple(allocator_arg_t, const Alloc& a, const pair<U1, U2>&&); // C++2380 81 tuple& operator=(const tuple&); // constexpr in C++2082 constexpr const tuple& operator=(const tuple&) const; // C++2383 tuple& operator=(tuple&&) noexcept(is_nothrow_move_assignable_v<T> && ...); // constexpr in C++2084 constexpr const tuple& operator=(tuple&&) const; // C++2385 template <class... U>86 tuple& operator=(const tuple<U...>&); // constexpr in C++2087 template<class... UTypes>88 constexpr const tuple& operator=(const tuple<UTypes...>&) const; // C++2389 template <class... U>90 tuple& operator=(tuple<U...>&&); // constexpr in C++2091 template<class... UTypes>92 constexpr const tuple& operator=(tuple<UTypes...>&&) const; // C++2393 template <class U1, class U2>94 tuple& operator=(const pair<U1, U2>&); // iff sizeof...(T) == 2 // constexpr in C++2095 template<class U1, class U2>96 constexpr const tuple& operator=(const pair<U1, U2>&) const; // iff sizeof...(Types) == 2 // C++2397 template <class U1, class U2>98 tuple& operator=(pair<U1, U2>&&); // iff sizeof...(T) == 2 // constexpr in C++2099 template<class U1, class U2>100 constexpr const tuple& operator=(pair<U1, U2>&&) const; // iff sizeof...(Types) == 2 // C++23101 102 template<class U, size_t N>103 tuple& operator=(array<U, N> const&) // iff sizeof...(T) == N, EXTENSION104 template<class U, size_t N>105 tuple& operator=(array<U, N>&&) // iff sizeof...(T) == N, EXTENSION106 107 void swap(tuple&) noexcept(AND(swap(declval<T&>(), declval<T&>())...)); // constexpr in C++20108 constexpr void swap(const tuple&) const noexcept(see-below); // C++23109 110 template<tuple-like UTuple>111 friend constexpr bool operator==(const tuple& t, const UTuple& u); // C++23112 template<tuple-like UTuple>113 friend constexpr auto operator<=>(const tuple& t, const UTuple& u); // C++23114};115 116 117template<class... TTypes, class... UTypes, template<class> class TQual, template<class> class UQual> // since C++23118 requires requires { typename tuple<common_reference_t<TQual<TTypes>, UQual<UTypes>>...>; }119struct basic_common_reference<tuple<TTypes...>, tuple<UTypes...>, TQual, UQual> {120 using type = tuple<common_reference_t<TQual<TTypes>, UQual<UTypes>>...>;121};122 123template<class... TTypes, class... UTypes> // since C++23124 requires requires { typename tuple<common_type_t<TTypes, UTypes>...>; }125struct common_type<tuple<TTypes...>, tuple<UTypes...>> {126 using type = tuple<common_type_t<TTypes, UTypes>...>;127};128 129template <class ...T>130tuple(T...) -> tuple<T...>; // since C++17131template <class T1, class T2>132tuple(pair<T1, T2>) -> tuple<T1, T2>; // since C++17133template <class Alloc, class ...T>134tuple(allocator_arg_t, Alloc, T...) -> tuple<T...>; // since C++17135template <class Alloc, class T1, class T2>136tuple(allocator_arg_t, Alloc, pair<T1, T2>) -> tuple<T1, T2>; // since C++17137template <class Alloc, class ...T>138tuple(allocator_arg_t, Alloc, tuple<T...>) -> tuple<T...>; // since C++17139 140struct ignore-type { // exposition only // Since C++26141 constexpr const ignore-type&142 operator=(const auto &) const noexcept143 { return *this; }144};145inline constexpr ignore-type ignore;146 147template <class... T> tuple<V...> make_tuple(T&&...); // constexpr in C++14148template <class... T> tuple<ATypes...> forward_as_tuple(T&&...) noexcept; // constexpr in C++14149template <class... T> tuple<T&...> tie(T&...) noexcept; // constexpr in C++14150template <class... Tuples> tuple<CTypes...> tuple_cat(Tuples&&... tpls); // constexpr in C++14151 152// [tuple.apply], calling a function with a tuple of arguments:153template <class F, class Tuple>154 constexpr decltype(auto) apply(F&& f, Tuple&& t) noexcept(see below); // C++17 noexcept since C++23155template <class T, class Tuple>156 constexpr T make_from_tuple(Tuple&& t); // C++17157 158// 20.4.1.4, tuple helper classes:159template <class T> struct tuple_size; // undefined160template <class... T> struct tuple_size<tuple<T...>>;161template <class T>162 inline constexpr size_t tuple_size_v = tuple_size<T>::value; // C++17163template <size_t I, class T> struct tuple_element; // undefined164template <size_t I, class... T> struct tuple_element<I, tuple<T...>>;165template <size_t I, class T>166 using tuple_element_t = typename tuple_element <I, T>::type; // C++14167 168// 20.4.1.5, element access:169template <size_t I, class... T>170 typename tuple_element<I, tuple<T...>>::type&171 get(tuple<T...>&) noexcept; // constexpr in C++14172template <size_t I, class... T>173 const typename tuple_element<I, tuple<T...>>::type&174 get(const tuple<T...>&) noexcept; // constexpr in C++14175template <size_t I, class... T>176 typename tuple_element<I, tuple<T...>>::type&&177 get(tuple<T...>&&) noexcept; // constexpr in C++14178template <size_t I, class... T>179 const typename tuple_element<I, tuple<T...>>::type&&180 get(const tuple<T...>&&) noexcept; // constexpr in C++14181 182template <class T1, class... T>183 constexpr T1& get(tuple<T...>&) noexcept; // C++14184template <class T1, class... T>185 constexpr const T1& get(const tuple<T...>&) noexcept; // C++14186template <class T1, class... T>187 constexpr T1&& get(tuple<T...>&&) noexcept; // C++14188template <class T1, class... T>189 constexpr const T1&& get(const tuple<T...>&&) noexcept; // C++14190 191// 20.4.1.6, relational operators:192template<class... T, class... U> bool operator==(const tuple<T...>&, const tuple<U...>&); // constexpr in C++14193template<class... T, class... U> bool operator<(const tuple<T...>&, const tuple<U...>&); // constexpr in C++14, removed in C++20194template<class... T, class... U> bool operator!=(const tuple<T...>&, const tuple<U...>&); // constexpr in C++14, removed in C++20195template<class... T, class... U> bool operator>(const tuple<T...>&, const tuple<U...>&); // constexpr in C++14, removed in C++20196template<class... T, class... U> bool operator<=(const tuple<T...>&, const tuple<U...>&); // constexpr in C++14, removed in C++20197template<class... T, class... U> bool operator>=(const tuple<T...>&, const tuple<U...>&); // constexpr in C++14, removed in C++20198template<class... T, class... U>199 constexpr common_comparison_category_t<synth-three-way-result<T, U>...>200 operator<=>(const tuple<T...>&, const tuple<U...>&); // since C++20201 202template <class... Types, class Alloc>203 struct uses_allocator<tuple<Types...>, Alloc>;204 205template <class... Types>206 void207 swap(tuple<Types...>& x, tuple<Types...>& y) noexcept(noexcept(x.swap(y)));208 209template <class... Types>210 constexpr void swap(const tuple<Types...>& x, const tuple<Types...>& y) noexcept(see-below); // C++23211 212} // std213 214*/215 216// clang-format on217 218#if __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)219# include <__cxx03/__config>220#else221# include <__compare/common_comparison_category.h>222# include <__compare/ordering.h>223# include <__compare/synth_three_way.h>224# include <__concepts/boolean_testable.h>225# include <__config>226# include <__cstddef/size_t.h>227# include <__fwd/array.h>228# include <__fwd/get.h>229# include <__fwd/pair.h>230# include <__fwd/tuple.h>231# include <__memory/allocator_arg_t.h>232# include <__memory/uses_allocator.h>233# include <__tuple/find_index.h>234# include <__tuple/ignore.h>235# include <__tuple/tuple_element.h>236# include <__tuple/tuple_like.h>237# include <__tuple/tuple_size.h>238# include <__type_traits/common_reference.h>239# include <__type_traits/common_type.h>240# include <__type_traits/conditional.h>241# include <__type_traits/conjunction.h>242# include <__type_traits/copy_cvref.h>243# include <__type_traits/disjunction.h>244# include <__type_traits/enable_if.h>245# include <__type_traits/invoke.h>246# include <__type_traits/is_assignable.h>247# include <__type_traits/is_constructible.h>248# include <__type_traits/is_convertible.h>249# include <__type_traits/is_empty.h>250# include <__type_traits/is_final.h>251# include <__type_traits/is_implicitly_default_constructible.h>252# include <__type_traits/is_nothrow_assignable.h>253# include <__type_traits/is_nothrow_constructible.h>254# include <__type_traits/is_reference.h>255# include <__type_traits/is_same.h>256# include <__type_traits/is_swappable.h>257# include <__type_traits/is_trivially_relocatable.h>258# include <__type_traits/lazy.h>259# include <__type_traits/maybe_const.h>260# include <__type_traits/nat.h>261# include <__type_traits/negation.h>262# include <__type_traits/reference_constructs_from_temporary.h>263# include <__type_traits/remove_cv.h>264# include <__type_traits/remove_cvref.h>265# include <__type_traits/remove_reference.h>266# include <__type_traits/type_list.h>267# include <__type_traits/unwrap_ref.h>268# include <__utility/declval.h>269# include <__utility/forward.h>270# include <__utility/integer_sequence.h>271# include <__utility/move.h>272# include <__utility/swap.h>273# include <version>274 275// standard-mandated includes276 277// [tuple.syn]278# include <compare>279 280# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)281# pragma GCC system_header282# endif283 284_LIBCPP_PUSH_MACROS285# include <__undef_macros>286 287_LIBCPP_BEGIN_NAMESPACE_STD288 289# ifndef _LIBCPP_CXX03_LANG290 291template <size_t _Ip, class _Tp, class _Up>292_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool __tuple_compare_equal(const _Tp& __x, const _Up& __y) {293 if constexpr (_Ip == 0)294 return true;295 else296 return std::__tuple_compare_equal<_Ip - 1>(__x, __y) && std::get<_Ip - 1>(__x) == std::get<_Ip - 1>(__y);297}298 299# if _LIBCPP_STD_VER >= 26300template <class _Tp, class _Up, class _IndexSeq = make_index_sequence<tuple_size_v<_Tp>>>301inline constexpr bool __can_tuple_compare_equal = false;302 303// TODO(LLVM 23): Remove `tuple_size_v<_Tp> == tuple_size_v<_Up>` here once once LLVM-20 support ends304// because the resolution of CWG2369 landed in LLVM-21.305template <class _Tp, class _Up, size_t... _Is>306 requires(tuple_size_v<_Tp> == tuple_size_v<_Up>)307inline constexpr bool __can_tuple_compare_equal<_Tp, _Up, index_sequence<_Is...>> =308 __all<requires(const tuple_element_t<_Is, _Tp>& __t, const tuple_element_t<_Is, _Up>& __u) {309 { __t == __u } -> __boolean_testable;310 }...>::value;311# endif // _LIBCPP_STD_VER >= 26312 313# if _LIBCPP_STD_VER >= 20314template <class _Ret, class _Tp, class _Up, size_t... _Is>315_LIBCPP_HIDE_FROM_ABI constexpr _Ret __tuple_compare_three_way(const _Tp& __x, const _Up& __y, index_sequence<_Is...>) {316 _Ret __result = strong_ordering::equal;317 static_cast<void>(318 ((__result = std::__synth_three_way(std::get<_Is>(__x), std::get<_Is>(__y)), __result != 0) || ...));319 return __result;320}321# endif // _LIBCPP_STD_VER >= 20322 323# if _LIBCPP_STD_VER >= 23324template <class _Tp>325concept __tuple_like_no_tuple = __tuple_like<_Tp> && !__is_tuple_v<_Tp>;326 327template <class _Tp, class _Up, class _IndexSeq>328struct __tuple_common_comparison_category_impl {};329 330// TODO(LLVM 23): Remove `tuple_size_v<_Tp> == tuple_size_v<_Up>` here once once LLVM-20 support ends331// because the resolution of CWG2369 landed in LLVM-21.332template <class _Tp, class _Up, size_t... _Is>333 requires(tuple_size_v<_Tp> == tuple_size_v<_Up>) && requires {334 typename common_comparison_category_t<335 __synth_three_way_result<tuple_element_t<_Is, _Tp>, tuple_element_t<_Is, _Up>>...>;336 }337struct __tuple_common_comparison_category_impl<_Tp, _Up, index_sequence<_Is...>> {338 using type _LIBCPP_NODEBUG =339 common_comparison_category_t<__synth_three_way_result<tuple_element_t<_Is, _Tp>, tuple_element_t<_Is, _Up>>...>;340};341 342template <__tuple_like _Tp, __tuple_like _Up>343using __tuple_common_comparison_category _LIBCPP_NODEBUG =344 __tuple_common_comparison_category_impl<_Tp, _Up, make_index_sequence<tuple_size_v<_Tp>>>::type;345# endif // _LIBCPP_STD_VER >= 23346 347// __tuple_leaf348 349template <size_t _Ip, class _Hp, bool = is_empty<_Hp>::value && !__is_final_v<_Hp> >350class __tuple_leaf;351 352template <size_t _Ip, class _Hp, bool _Ep>353inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void354swap(__tuple_leaf<_Ip, _Hp, _Ep>& __x, __tuple_leaf<_Ip, _Hp, _Ep>& __y) noexcept(__is_nothrow_swappable_v<_Hp>) {355 swap(__x.get(), __y.get());356}357 358template <size_t _Ip, class _Hp, bool _Ep>359_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void360swap(const __tuple_leaf<_Ip, _Hp, _Ep>& __x,361 const __tuple_leaf<_Ip, _Hp, _Ep>& __y) noexcept(__is_nothrow_swappable_v<const _Hp>) {362 swap(__x.get(), __y.get());363}364 365template <size_t _Ip, class _Hp, bool>366class __tuple_leaf {367 _Hp __value_;368 369public:370 _LIBCPP_CONSTEXPR_SINCE_CXX14 __tuple_leaf& operator=(const __tuple_leaf&) = delete;371 372 _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf() noexcept(is_nothrow_default_constructible<_Hp>::value) : __value_() {373 static_assert(!is_reference<_Hp>::value, "Attempted to default construct a reference element in a tuple");374 }375 376 template <class _Alloc>377 _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf(integral_constant<int, 0>, const _Alloc&) : __value_() {378 static_assert(!is_reference<_Hp>::value, "Attempted to default construct a reference element in a tuple");379 }380 381 template <class _Alloc>382 _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf(integral_constant<int, 1>, const _Alloc& __a)383 : __value_(allocator_arg_t(), __a) {384 static_assert(!is_reference<_Hp>::value, "Attempted to default construct a reference element in a tuple");385 }386 387 template <class _Alloc>388 _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf(integral_constant<int, 2>, const _Alloc& __a) : __value_(__a) {389 static_assert(!is_reference<_Hp>::value, "Attempted to default construct a reference element in a tuple");390 }391 392 template <393 class _Tp,394 __enable_if_t<_And<_IsNotSame<__remove_cvref_t<_Tp>, __tuple_leaf>, is_constructible<_Hp, _Tp> >::value, int> = 0>395 _LIBCPP_HIDE_FROM_ABI396 _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_leaf(_Tp&& __t) noexcept(is_nothrow_constructible<_Hp, _Tp>::value)397 : __value_(std::forward<_Tp>(__t)) {398 static_assert(!__reference_constructs_from_temporary_v<_Hp, _Tp&&>,399 "Attempted construction of reference element binds to a temporary whose lifetime has ended");400 }401 402 template <class _Tp, class _Alloc>403 _LIBCPP_HIDE_FROM_ABI404 _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_leaf(integral_constant<int, 0>, const _Alloc&, _Tp&& __t)405 : __value_(std::forward<_Tp>(__t)) {406 static_assert(!__reference_constructs_from_temporary_v<_Hp, _Tp&&>,407 "Attempted construction of reference element binds to a temporary whose lifetime has ended");408 }409 410 template <class _Tp, class _Alloc>411 _LIBCPP_HIDE_FROM_ABI412 _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_leaf(integral_constant<int, 1>, const _Alloc& __a, _Tp&& __t)413 : __value_(allocator_arg_t(), __a, std::forward<_Tp>(__t)) {414 static_assert(!is_reference<_Hp>::value, "Attempted to uses-allocator construct a reference element in a tuple");415 }416 417 template <class _Tp, class _Alloc>418 _LIBCPP_HIDE_FROM_ABI419 _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_leaf(integral_constant<int, 2>, const _Alloc& __a, _Tp&& __t)420 : __value_(std::forward<_Tp>(__t), __a) {421 static_assert(!is_reference<_Hp>::value, "Attempted to uses-allocator construct a reference element in a tuple");422 }423 424 _LIBCPP_HIDE_FROM_ABI __tuple_leaf(const __tuple_leaf& __t) = default;425 _LIBCPP_HIDE_FROM_ABI __tuple_leaf(__tuple_leaf&& __t) = default;426 427 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int428 swap(__tuple_leaf& __t) noexcept(__is_nothrow_swappable_v<__tuple_leaf>) {429 std::swap(*this, __t);430 return 0;431 }432 433 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int swap(const __tuple_leaf& __t) const434 noexcept(__is_nothrow_swappable_v<const __tuple_leaf>) {435 std::swap(*this, __t);436 return 0;437 }438 439 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Hp& get() _NOEXCEPT { return __value_; }440 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Hp& get() const _NOEXCEPT { return __value_; }441};442 443template <size_t _Ip, class _Hp>444class __tuple_leaf<_Ip, _Hp, true> : private __remove_cv_t<_Hp> {445public:446 _LIBCPP_CONSTEXPR_SINCE_CXX14 __tuple_leaf& operator=(const __tuple_leaf&) = delete;447 448 _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf() noexcept(is_nothrow_default_constructible<_Hp>::value) {}449 450 template <class _Alloc>451 _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf(integral_constant<int, 0>, const _Alloc&) {}452 453 template <class _Alloc>454 _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf(integral_constant<int, 1>, const _Alloc& __a)455 : _Hp(allocator_arg_t(), __a) {}456 457 template <class _Alloc>458 _LIBCPP_HIDE_FROM_ABI constexpr __tuple_leaf(integral_constant<int, 2>, const _Alloc& __a) : _Hp(__a) {}459 460 template <class _Tp,461 __enable_if_t< _And< _IsNotSame<__remove_cvref_t<_Tp>, __tuple_leaf>, is_constructible<_Hp, _Tp> >::value,462 int> = 0>463 _LIBCPP_HIDE_FROM_ABI464 _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_leaf(_Tp&& __t) noexcept(is_nothrow_constructible<_Hp, _Tp>::value)465 : _Hp(std::forward<_Tp>(__t)) {}466 467 template <class _Tp, class _Alloc>468 _LIBCPP_HIDE_FROM_ABI constexpr explicit __tuple_leaf(integral_constant<int, 0>, const _Alloc&, _Tp&& __t)469 : _Hp(std::forward<_Tp>(__t)) {}470 471 template <class _Tp, class _Alloc>472 _LIBCPP_HIDE_FROM_ABI constexpr explicit __tuple_leaf(integral_constant<int, 1>, const _Alloc& __a, _Tp&& __t)473 : _Hp(allocator_arg_t(), __a, std::forward<_Tp>(__t)) {}474 475 template <class _Tp, class _Alloc>476 _LIBCPP_HIDE_FROM_ABI constexpr explicit __tuple_leaf(integral_constant<int, 2>, const _Alloc& __a, _Tp&& __t)477 : _Hp(std::forward<_Tp>(__t), __a) {}478 479 __tuple_leaf(__tuple_leaf const&) = default;480 __tuple_leaf(__tuple_leaf&&) = default;481 482 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int483 swap(__tuple_leaf& __t) noexcept(__is_nothrow_swappable_v<__tuple_leaf>) {484 std::swap(*this, __t);485 return 0;486 }487 488 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 int swap(const __tuple_leaf& __rhs) const489 noexcept(__is_nothrow_swappable_v<const __tuple_leaf>) {490 std::swap(*this, __rhs);491 return 0;492 }493 494 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Hp& get() _NOEXCEPT { return static_cast<_Hp&>(*this); }495 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const _Hp& get() const _NOEXCEPT {496 return static_cast<const _Hp&>(*this);497 }498};499 500template <class... _Tp>501_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void __swallow(_Tp&&...) _NOEXCEPT {}502 503// __tuple_impl504 505template <class _Indx, class... _Tp>506struct __tuple_impl;507 508struct __forward_args {};509struct __value_init {};510struct __from_tuple {};511 512template <size_t... _Indx, class... _Tp>513struct _LIBCPP_DECLSPEC_EMPTY_BASES514 __tuple_impl<__index_sequence<_Indx...>, _Tp...> : public __tuple_leaf<_Indx, _Tp>... {515 _LIBCPP_HIDE_FROM_ABI constexpr __tuple_impl() noexcept(516 __all<is_nothrow_default_constructible<_Tp>::value...>::value) {}517 518 template <class... _Args>519 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_impl(__forward_args, _Args&&... __args)520 : __tuple_leaf<_Indx, _Tp>(std::forward<_Args>(__args))... {}521 522 template <class _Alloc>523 _LIBCPP_HIDE_FROM_ABI524 _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_impl(allocator_arg_t, const _Alloc& __alloc, __value_init)525 : __tuple_leaf<_Indx, _Tp>(__uses_alloc_ctor<_Tp, _Alloc>(), __alloc)... {}526 527 template <class _Alloc, class... _Args>528 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit __tuple_impl(529 allocator_arg_t, const _Alloc& __alloc, __forward_args, _Args&&... __args)530 : __tuple_leaf<_Indx, _Tp>(__uses_alloc_ctor<_Tp, _Alloc, _Args>(), __alloc, std::forward<_Args>(__args))... {}531 532 template <class _Tuple>533 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __tuple_impl(__from_tuple, _Tuple&& __t) noexcept(534 (__all<is_nothrow_constructible<_Tp, __copy_cvref_t<_Tuple, __tuple_element_t<_Indx, __remove_cvref_t<_Tuple>>>>::535 value...>::value))536 : __tuple_leaf<_Indx, _Tp>(537 std::forward<__copy_cvref_t<_Tuple, __tuple_element_t<_Indx, __remove_cvref_t<_Tuple>>>>(538 std::get<_Indx>(__t)))... {}539 540 template <class _Alloc, class _Tuple>541 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14542 __tuple_impl(allocator_arg_t, const _Alloc& __a, __from_tuple, _Tuple&& __t)543 : __tuple_leaf<_Indx, _Tp>(544 __uses_alloc_ctor<_Tp,545 _Alloc,546 __copy_cvref_t<_Tuple, __tuple_element_t<_Indx, __remove_cvref_t<_Tuple>>>>(),547 __a,548 std::forward<__copy_cvref_t<_Tuple, __tuple_element_t<_Indx, __remove_cvref_t<_Tuple>>>>(549 std::get<_Indx>(__t)))... {}550 551 __tuple_impl(const __tuple_impl&) = default;552 __tuple_impl(__tuple_impl&&) = default;553 554 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void555 swap(__tuple_impl& __t) noexcept(__all<__is_nothrow_swappable_v<_Tp>...>::value) {556 std::__swallow(__tuple_leaf<_Indx, _Tp>::swap(static_cast<__tuple_leaf<_Indx, _Tp>&>(__t))...);557 }558 559 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void swap(const __tuple_impl& __t) const560 noexcept(__all<__is_nothrow_swappable_v<const _Tp>...>::value) {561 std::__swallow(__tuple_leaf<_Indx, _Tp>::swap(static_cast<const __tuple_leaf<_Indx, _Tp>&>(__t))...);562 }563};564 565template <class _Dest, class _Source, size_t... _Np>566_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void567__memberwise_copy_assign(_Dest& __dest, _Source const& __source, __index_sequence<_Np...>) {568 std::__swallow(((std::get<_Np>(__dest) = std::get<_Np>(__source)), void(), 0)...);569}570 571template <class _Dest, class _Source, class... _Up, size_t... _Np>572_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 void573__memberwise_forward_assign(_Dest& __dest, _Source&& __source, __type_list<_Up...>, __index_sequence<_Np...>) {574 std::__swallow(((std::get<_Np>(__dest) = std::forward<_Up>(std::get<_Np>(__source))), void(), 0)...);575}576 577template <class... _Tp>578class _LIBCPP_NO_SPECIALIZATIONS tuple {579 typedef __tuple_impl<__make_index_sequence<sizeof...(_Tp)>, _Tp...> _BaseT;580 581 _BaseT __base_;582 583 template <size_t _Jp, class... _Up>584 friend _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Jp, tuple<_Up...> >::type& get(tuple<_Up...>&) _NOEXCEPT;585 template <size_t _Jp, class... _Up>586 friend _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Jp, tuple<_Up...> >::type&587 get(const tuple<_Up...>&) _NOEXCEPT;588 template <size_t _Jp, class... _Up>589 friend _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Jp, tuple<_Up...> >::type&&590 get(tuple<_Up...>&&) _NOEXCEPT;591 template <size_t _Jp, class... _Up>592 friend _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Jp, tuple<_Up...> >::type&&593 get(const tuple<_Up...>&&) _NOEXCEPT;594 595public:596 using __trivially_relocatable _LIBCPP_NODEBUG =597 __conditional_t<_And<__libcpp_is_trivially_relocatable<_Tp>...>::value, tuple, void>;598 599 // [tuple.cnstr]600 601 // tuple() constructors (including allocator_arg_t variants)602 template <template <class...> class _IsImpDefault = __is_implicitly_default_constructible,603 template <class...> class _IsDefault = is_default_constructible,604 __enable_if_t< _And< _IsDefault<_Tp>... >::value, int> = 0>605 _LIBCPP_HIDE_FROM_ABI constexpr explicit(_Not<_Lazy<_And, _IsImpDefault<_Tp>...> >::value)606 tuple() noexcept(_And<is_nothrow_default_constructible<_Tp>...>::value) {}607 608 template <class _Alloc,609 template <class...> class _IsImpDefault = __is_implicitly_default_constructible,610 template <class...> class _IsDefault = is_default_constructible,611 __enable_if_t< _And< _IsDefault<_Tp>... >::value, int> = 0>612 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_Lazy<_And, _IsImpDefault<_Tp>...> >::value)613 tuple(allocator_arg_t, _Alloc const& __a)614 : __base_(allocator_arg_t(), __a, __value_init{}) {}615 616 // tuple(const T&...) constructors (including allocator_arg_t variants)617 template <template <class...> class _And = _And,618 __enable_if_t< _And< _BoolConstant<sizeof...(_Tp) >= 1>, is_copy_constructible<_Tp>... >::value, int> = 0>619 _LIBCPP_HIDE_FROM_ABI620 _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(_Not<_Lazy<_And, is_convertible<const _Tp&, _Tp>...> >::value)621 tuple(const _Tp&... __t) noexcept(_And<is_nothrow_copy_constructible<_Tp>...>::value)622 : __base_(__forward_args{}, __t...) {}623 624 template <class _Alloc,625 template <class...> class _And = _And,626 __enable_if_t< _And< _BoolConstant<sizeof...(_Tp) >= 1>, is_copy_constructible<_Tp>... >::value, int> = 0>627 _LIBCPP_HIDE_FROM_ABI628 _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_Lazy<_And, is_convertible<const _Tp&, _Tp>...> >::value)629 tuple(allocator_arg_t, const _Alloc& __a, const _Tp&... __t)630 : __base_(allocator_arg_t(), __a, __forward_args{}, __t...) {}631 632 // tuple(U&& ...) constructors (including allocator_arg_t variants)633 template <class... _Up>634 struct _IsThisTuple : false_type {};635 template <class _Up>636 struct _IsThisTuple<_Up> : is_same<__remove_cvref_t<_Up>, tuple> {};637 638 template <class... _Up>639 struct _EnableUTypesCtor640 : _And< _BoolConstant<sizeof...(_Tp) >= 1>,641 _Not<_IsThisTuple<_Up...> >, // extension to allow mis-behaved user constructors642 is_constructible<_Tp, _Up>... > {};643 644 template <class... _Up,645 __enable_if_t< _And< _BoolConstant<sizeof...(_Up) == sizeof...(_Tp)>, _EnableUTypesCtor<_Up...> >::value,646 int> = 0>647 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(_Not<_Lazy<_And, is_convertible<_Up, _Tp>...> >::value)648 tuple(_Up&&... __u) noexcept(_And<is_nothrow_constructible<_Tp, _Up>...>::value)649 : __base_(__forward_args{}, std::forward<_Up>(__u)...) {}650 651 template <class _Alloc,652 class... _Up,653 __enable_if_t< _And< _BoolConstant<sizeof...(_Up) == sizeof...(_Tp)>, _EnableUTypesCtor<_Up...> >::value,654 int> = 0>655 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_Lazy<_And, is_convertible<_Up, _Tp>...> >::value)656 tuple(allocator_arg_t, const _Alloc& __a, _Up&&... __u)657 : __base_(allocator_arg_t(), __a, __forward_args{}, std::forward<_Up>(__u)...) {}658 659 // Copy and move constructors (including the allocator_arg_t variants)660 tuple(const tuple&) = default;661 tuple(tuple&&) = default;662 663 template <class _Alloc,664 template <class...> class _And = _And,665 __enable_if_t< _And<is_copy_constructible<_Tp>...>::value, int> = 0>666 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple(allocator_arg_t, const _Alloc& __alloc, const tuple& __t)667 : __base_(allocator_arg_t(), __alloc, __from_tuple(), __t) {}668 669 template <class _Alloc,670 template <class...> class _And = _And,671 __enable_if_t< _And<is_move_constructible<_Tp>...>::value, int> = 0>672 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple(allocator_arg_t, const _Alloc& __alloc, tuple&& __t)673 : __base_(allocator_arg_t(), __alloc, __from_tuple(), std::move(__t)) {}674 675 // tuple(const tuple<U...>&) constructors (including allocator_arg_t variants)676 677 template <class _OtherTuple, class _DecayedOtherTuple = __remove_cvref_t<_OtherTuple>, class = void>678 struct _EnableCtorFromUTypesTuple : false_type {};679 680 template <class _OtherTuple, class... _Up>681 struct _EnableCtorFromUTypesTuple<682 _OtherTuple,683 tuple<_Up...>,684 // the length of the packs needs to checked first otherwise the 2 packs cannot be expanded simultaneously below685 __enable_if_t<sizeof...(_Up) == sizeof...(_Tp)>>686 : _And<687 // the two conditions below are not in spec. The purpose is to disable the UTypes Ctor when copy/move Ctor688 // can work. Otherwise, is_constructible can trigger hard error in those cases689 // https://godbolt.org/z/M94cGdKcE690 _Not<is_same<_OtherTuple, const tuple&> >,691 _Not<is_same<_OtherTuple, tuple&&> >,692 is_constructible<_Tp, __copy_cvref_t<_OtherTuple, _Up> >...,693 _Lazy<_Or,694 _BoolConstant<sizeof...(_Tp) != 1>,695 // _Tp and _Up are 1-element packs - the pack expansions look696 // weird to avoid tripping up the type traits in degenerate cases697 _Lazy<_And,698 _Not<is_same<_Tp, _Up> >...,699 _Not<is_convertible<_OtherTuple, _Tp> >...,700 _Not<is_constructible<_Tp, _OtherTuple> >... > > > {};701 702 template <class... _Up, __enable_if_t< _And< _EnableCtorFromUTypesTuple<const tuple<_Up...>&> >::value, int> = 0>703 _LIBCPP_HIDE_FROM_ABI704 _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(_Not<_Lazy<_And, is_convertible<const _Up&, _Tp>...> >::value)705 tuple(const tuple<_Up...>& __t) noexcept(_And<is_nothrow_constructible<_Tp, const _Up&>...>::value)706 : __base_(__from_tuple(), __t) {}707 708 template <class... _Up,709 class _Alloc,710 __enable_if_t< _And< _EnableCtorFromUTypesTuple<const tuple<_Up...>&> >::value, int> = 0>711 _LIBCPP_HIDE_FROM_ABI712 _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_Lazy<_And, is_convertible<const _Up&, _Tp>...> >::value)713 tuple(allocator_arg_t, const _Alloc& __a, const tuple<_Up...>& __t)714 : __base_(allocator_arg_t(), __a, __from_tuple(), __t) {}715 716# if _LIBCPP_STD_VER >= 23717 // tuple(tuple<U...>&) constructors (including allocator_arg_t variants)718 719 template <class... _Up, enable_if_t< _EnableCtorFromUTypesTuple<tuple<_Up...>&>::value>* = nullptr>720 _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_Lazy<_And, is_convertible<_Up&, _Tp>...>::value) tuple(tuple<_Up...>& __t)721 : __base_(__from_tuple(), __t) {}722 723 template <class _Alloc, class... _Up, enable_if_t< _EnableCtorFromUTypesTuple<tuple<_Up...>&>::value>* = nullptr>724 _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_Lazy<_And, is_convertible<_Up&, _Tp>...>::value)725 tuple(allocator_arg_t, const _Alloc& __alloc, tuple<_Up...>& __t)726 : __base_(allocator_arg_t(), __alloc, __from_tuple(), __t) {}727# endif // _LIBCPP_STD_VER >= 23728 729 // tuple(tuple<U...>&&) constructors (including allocator_arg_t variants)730 template <class... _Up, __enable_if_t< _And< _EnableCtorFromUTypesTuple<tuple<_Up...>&&> >::value, int> = 0>731 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(_Not<_Lazy<_And, is_convertible<_Up, _Tp>...> >::value)732 tuple(tuple<_Up...>&& __t) noexcept(_And<is_nothrow_constructible<_Tp, _Up>...>::value)733 : __base_(__from_tuple(), std::move(__t)) {}734 735 template <class _Alloc,736 class... _Up,737 __enable_if_t< _And< _EnableCtorFromUTypesTuple<tuple<_Up...>&&> >::value, int> = 0>738 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_Lazy<_And, is_convertible<_Up, _Tp>...> >::value)739 tuple(allocator_arg_t, const _Alloc& __a, tuple<_Up...>&& __t)740 : __base_(allocator_arg_t(), __a, __from_tuple(), std::move(__t)) {}741 742# if _LIBCPP_STD_VER >= 23743 // tuple(const tuple<U...>&&) constructors (including allocator_arg_t variants)744 745 template <class... _Up, enable_if_t< _EnableCtorFromUTypesTuple<const tuple<_Up...>&&>::value>* = nullptr>746 _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_Lazy<_And, is_convertible<const _Up&&, _Tp>...>::value)747 tuple(const tuple<_Up...>&& __t)748 : __base_(__from_tuple(), std::move(__t)) {}749 750 template <class _Alloc,751 class... _Up,752 enable_if_t< _EnableCtorFromUTypesTuple<const tuple<_Up...>&&>::value>* = nullptr>753 _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_Lazy<_And, is_convertible<const _Up&&, _Tp>...>::value)754 tuple(allocator_arg_t, const _Alloc& __alloc, const tuple<_Up...>&& __t)755 : __base_(allocator_arg_t(), __alloc, __from_tuple(), std::move(__t)) {}756# endif // _LIBCPP_STD_VER >= 23757 758 // tuple(const pair<U1, U2>&) constructors (including allocator_arg_t variants)759 760 template <template <class...> class _Pred,761 class _Pair,762 class _DecayedPair = __remove_cvref_t<_Pair>,763 class _Tuple = tuple>764 struct _CtorPredicateFromPair : false_type {};765 766 template <template <class...> class _Pred, class _Pair, class _Up1, class _Up2, class _Tp1, class _Tp2>767 struct _CtorPredicateFromPair<_Pred, _Pair, pair<_Up1, _Up2>, tuple<_Tp1, _Tp2> >768 : _And< _Pred<_Tp1, __copy_cvref_t<_Pair, _Up1> >, _Pred<_Tp2, __copy_cvref_t<_Pair, _Up2> > > {};769 770 template <class _Pair>771 struct _EnableCtorFromPair : _CtorPredicateFromPair<is_constructible, _Pair> {};772 773 template <class _Pair>774 struct _NothrowConstructibleFromPair : _CtorPredicateFromPair<is_nothrow_constructible, _Pair> {};775 776 template <class _Pair, class _DecayedPair = __remove_cvref_t<_Pair>, class _Tuple = tuple>777 struct _BothImplicitlyConvertible : false_type {};778 779 template <class _Pair, class _Up1, class _Up2, class _Tp1, class _Tp2>780 struct _BothImplicitlyConvertible<_Pair, pair<_Up1, _Up2>, tuple<_Tp1, _Tp2> >781 : _And< is_convertible<__copy_cvref_t<_Pair, _Up1>, _Tp1>, is_convertible<__copy_cvref_t<_Pair, _Up2>, _Tp2> > {};782 783 template <class _Up1,784 class _Up2,785 template <class...> class _And = _And,786 __enable_if_t< _And< _EnableCtorFromPair<const pair<_Up1, _Up2>&> >::value, int> = 0>787 _LIBCPP_HIDE_FROM_ABI788 _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(_Not<_BothImplicitlyConvertible<const pair<_Up1, _Up2>&> >::value)789 tuple(const pair<_Up1, _Up2>& __p) noexcept(_NothrowConstructibleFromPair<const pair<_Up1, _Up2>&>::value)790 : __base_(__from_tuple(), __p) {}791 792 template <class _Alloc,793 class _Up1,794 class _Up2,795 template <class...> class _And = _And,796 __enable_if_t< _And< _EnableCtorFromPair<const pair<_Up1, _Up2>&> >::value, int> = 0>797 _LIBCPP_HIDE_FROM_ABI798 _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_BothImplicitlyConvertible<const pair<_Up1, _Up2>&> >::value)799 tuple(allocator_arg_t, const _Alloc& __a, const pair<_Up1, _Up2>& __p)800 : __base_(allocator_arg_t(), __a, __from_tuple(), __p) {}801 802# if _LIBCPP_STD_VER >= 23803 // tuple(pair<U1, U2>&) constructors (including allocator_arg_t variants)804 805 template <class _U1, class _U2, enable_if_t< _EnableCtorFromPair<pair<_U1, _U2>&>::value>* = nullptr>806 _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_BothImplicitlyConvertible<pair<_U1, _U2>&>::value)807 tuple(pair<_U1, _U2>& __p)808 : __base_(__from_tuple(), __p) {}809 810 template <class _Alloc,811 class _U1,812 class _U2,813 enable_if_t< _EnableCtorFromPair<std::pair<_U1, _U2>&>::value>* = nullptr>814 _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_BothImplicitlyConvertible<pair<_U1, _U2>&>::value)815 tuple(allocator_arg_t, const _Alloc& __alloc, pair<_U1, _U2>& __p)816 : __base_(allocator_arg_t(), __alloc, __from_tuple(), __p) {}817# endif818 819 // tuple(pair<U1, U2>&&) constructors (including allocator_arg_t variants)820 821 template <class _Up1,822 class _Up2,823 template <class...> class _And = _And,824 __enable_if_t< _And< _EnableCtorFromPair<pair<_Up1, _Up2>&&> >::value, int> = 0>825 _LIBCPP_HIDE_FROM_ABI826 _LIBCPP_CONSTEXPR_SINCE_CXX14 explicit(_Not<_BothImplicitlyConvertible<pair<_Up1, _Up2>&&> >::value)827 tuple(pair<_Up1, _Up2>&& __p) noexcept(_NothrowConstructibleFromPair<pair<_Up1, _Up2>&&>::value)828 : __base_(__from_tuple(), std::move(__p)) {}829 830 template <class _Alloc,831 class _Up1,832 class _Up2,833 template <class...> class _And = _And,834 __enable_if_t< _And< _EnableCtorFromPair<pair<_Up1, _Up2>&&> >::value, int> = 0>835 _LIBCPP_HIDE_FROM_ABI836 _LIBCPP_CONSTEXPR_SINCE_CXX20 explicit(_Not<_BothImplicitlyConvertible<pair<_Up1, _Up2>&&> >::value)837 tuple(allocator_arg_t, const _Alloc& __a, pair<_Up1, _Up2>&& __p)838 : __base_(allocator_arg_t(), __a, __from_tuple(), std::move(__p)) {}839 840# if _LIBCPP_STD_VER >= 23841 // tuple(const pair<U1, U2>&&) constructors (including allocator_arg_t variants)842 843 template <class _U1, class _U2, enable_if_t< _EnableCtorFromPair<const pair<_U1, _U2>&&>::value>* = nullptr>844 _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_BothImplicitlyConvertible<const pair<_U1, _U2>&&>::value)845 tuple(const pair<_U1, _U2>&& __p)846 : __base_(__from_tuple(), std::move(__p)) {}847 848 template <class _Alloc,849 class _U1,850 class _U2,851 enable_if_t< _EnableCtorFromPair<const pair<_U1, _U2>&&>::value>* = nullptr>852 _LIBCPP_HIDE_FROM_ABI constexpr explicit(!_BothImplicitlyConvertible<const pair<_U1, _U2>&&>::value)853 tuple(allocator_arg_t, const _Alloc& __alloc, const pair<_U1, _U2>&& __p)854 : __base_(allocator_arg_t(), __alloc, __from_tuple(), std::move(__p)) {}855# endif // _LIBCPP_STD_VER >= 23856 857 // [tuple.assign]858 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple&859 operator=(_If<_And<is_copy_assignable<_Tp>...>::value, tuple, __nat> const& __tuple) noexcept(860 _And<is_nothrow_copy_assignable<_Tp>...>::value) {861 std::__memberwise_copy_assign(*this, __tuple, __make_index_sequence<sizeof...(_Tp)>());862 return *this;863 }864 865# if _LIBCPP_STD_VER >= 23866 _LIBCPP_HIDE_FROM_ABI constexpr const tuple& operator=(tuple const& __tuple) const867 requires(_And<is_copy_assignable<const _Tp>...>::value)868 {869 std::__memberwise_copy_assign(*this, __tuple, __make_index_sequence<sizeof...(_Tp)>());870 return *this;871 }872 873 _LIBCPP_HIDE_FROM_ABI constexpr const tuple& operator=(tuple&& __tuple) const874 requires(_And<is_assignable<const _Tp&, _Tp>...>::value)875 {876 std::__memberwise_forward_assign(877 *this, std::move(__tuple), __type_list<_Tp...>(), __make_index_sequence<sizeof...(_Tp)>());878 return *this;879 }880# endif // _LIBCPP_STD_VER >= 23881 882 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple&883 operator=(_If<_And<is_move_assignable<_Tp>...>::value, tuple, __nat>&& __tuple) noexcept(884 _And<is_nothrow_move_assignable<_Tp>...>::value) {885 std::__memberwise_forward_assign(886 *this, std::move(__tuple), __type_list<_Tp...>(), __make_index_sequence<sizeof...(_Tp)>());887 return *this;888 }889 890 template <891 class... _Up,892 __enable_if_t< _And< _BoolConstant<sizeof...(_Tp) == sizeof...(_Up)>, is_assignable<_Tp&, _Up const&>... >::value,893 int> = 0>894 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple&895 operator=(tuple<_Up...> const& __tuple) noexcept(_And<is_nothrow_assignable<_Tp&, _Up const&>...>::value) {896 std::__memberwise_copy_assign(*this, __tuple, __make_index_sequence<sizeof...(_Tp)>());897 return *this;898 }899 900 template <class... _Up,901 __enable_if_t< _And< _BoolConstant<sizeof...(_Tp) == sizeof...(_Up)>, is_assignable<_Tp&, _Up>... >::value,902 int> = 0>903 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple&904 operator=(tuple<_Up...>&& __tuple) noexcept(_And<is_nothrow_assignable<_Tp&, _Up>...>::value) {905 std::__memberwise_forward_assign(906 *this, std::move(__tuple), __type_list<_Up...>(), __make_index_sequence<sizeof...(_Tp)>());907 return *this;908 }909 910# if _LIBCPP_STD_VER >= 23911 template <class... _UTypes,912 enable_if_t< _And<_BoolConstant<sizeof...(_Tp) == sizeof...(_UTypes)>,913 is_assignable<const _Tp&, const _UTypes&>...>::value>* = nullptr>914 _LIBCPP_HIDE_FROM_ABI constexpr const tuple& operator=(const tuple<_UTypes...>& __u) const {915 std::__memberwise_copy_assign(*this, __u, __make_index_sequence<sizeof...(_Tp)>());916 return *this;917 }918 919 template <class... _UTypes,920 enable_if_t< _And<_BoolConstant<sizeof...(_Tp) == sizeof...(_UTypes)>,921 is_assignable<const _Tp&, _UTypes>...>::value>* = nullptr>922 _LIBCPP_HIDE_FROM_ABI constexpr const tuple& operator=(tuple<_UTypes...>&& __u) const {923 std::__memberwise_forward_assign(*this, __u, __type_list<_UTypes...>(), __make_index_sequence<sizeof...(_Tp)>());924 return *this;925 }926# endif // _LIBCPP_STD_VER >= 23927 928 template <template <class...> class _Pred,929 bool _Const,930 class _Pair,931 class _DecayedPair = __remove_cvref_t<_Pair>,932 class _Tuple = tuple>933 struct _AssignPredicateFromPair : false_type {};934 935 template <template <class...> class _Pred, bool _Const, class _Pair, class _Up1, class _Up2, class _Tp1, class _Tp2>936 struct _AssignPredicateFromPair<_Pred, _Const, _Pair, pair<_Up1, _Up2>, tuple<_Tp1, _Tp2> >937 : _And<_Pred<__maybe_const<_Const, _Tp1>&, __copy_cvref_t<_Pair, _Up1> >,938 _Pred<__maybe_const<_Const, _Tp2>&, __copy_cvref_t<_Pair, _Up2> > > {};939 940 template <bool _Const, class _Pair>941 struct _EnableAssignFromPair : _AssignPredicateFromPair<is_assignable, _Const, _Pair> {};942 943 template <bool _Const, class _Pair>944 struct _NothrowAssignFromPair : _AssignPredicateFromPair<is_nothrow_assignable, _Const, _Pair> {};945 946# if _LIBCPP_STD_VER >= 23947 template <class _U1, class _U2, enable_if_t< _EnableAssignFromPair<true, const pair<_U1, _U2>&>::value>* = nullptr>948 _LIBCPP_HIDE_FROM_ABI constexpr const tuple& operator=(const pair<_U1, _U2>& __pair) const949 noexcept(_NothrowAssignFromPair<true, const pair<_U1, _U2>&>::value) {950 std::get<0>(*this) = __pair.first;951 std::get<1>(*this) = __pair.second;952 return *this;953 }954 955 template <class _U1, class _U2, enable_if_t< _EnableAssignFromPair<true, pair<_U1, _U2>&&>::value>* = nullptr>956 _LIBCPP_HIDE_FROM_ABI constexpr const tuple& operator=(pair<_U1, _U2>&& __pair) const957 noexcept(_NothrowAssignFromPair<true, pair<_U1, _U2>&&>::value) {958 std::get<0>(*this) = std::move(__pair.first);959 std::get<1>(*this) = std::move(__pair.second);960 return *this;961 }962# endif // _LIBCPP_STD_VER >= 23963 964 template <class _Up1,965 class _Up2,966 __enable_if_t< _EnableAssignFromPair<false, pair<_Up1, _Up2> const&>::value, int> = 0>967 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple&968 operator=(pair<_Up1, _Up2> const& __pair) noexcept(_NothrowAssignFromPair<false, pair<_Up1, _Up2> const&>::value) {969 std::get<0>(*this) = __pair.first;970 std::get<1>(*this) = __pair.second;971 return *this;972 }973 974 template <class _Up1, class _Up2, __enable_if_t< _EnableAssignFromPair<false, pair<_Up1, _Up2>&&>::value, int> = 0>975 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple&976 operator=(pair<_Up1, _Up2>&& __pair) noexcept(_NothrowAssignFromPair<false, pair<_Up1, _Up2>&&>::value) {977 std::get<0>(*this) = std::forward<_Up1>(__pair.first);978 std::get<1>(*this) = std::forward<_Up2>(__pair.second);979 return *this;980 }981 982 // EXTENSION983 template <984 class _Up,985 size_t _Np,986 __enable_if_t< _And< _BoolConstant<_Np == sizeof...(_Tp)>, is_assignable<_Tp&, _Up const&>... >::value, int> = 0>987 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple&988 operator=(array<_Up, _Np> const& __array) noexcept(_And<is_nothrow_assignable<_Tp&, _Up const&>...>::value) {989 std::__memberwise_copy_assign(*this, __array, __make_index_sequence<sizeof...(_Tp)>());990 return *this;991 }992 993 // EXTENSION994 template <class _Up,995 size_t _Np,996 class = void,997 __enable_if_t< _And< _BoolConstant<_Np == sizeof...(_Tp)>, is_assignable<_Tp&, _Up>... >::value, int> = 0>998 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple&999 operator=(array<_Up, _Np>&& __array) noexcept(_And<is_nothrow_assignable<_Tp&, _Up>...>::value) {1000 std::__memberwise_forward_assign(1001 *this, std::move(__array), __type_list<_If<true, _Up, _Tp>...>(), __make_index_sequence<sizeof...(_Tp)>());1002 return *this;1003 }1004 1005 // [tuple.swap]1006 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void1007 swap(tuple& __t) noexcept(__all<__is_nothrow_swappable_v<_Tp>...>::value) {1008 __base_.swap(__t.__base_);1009 }1010 1011# if _LIBCPP_STD_VER >= 231012 _LIBCPP_HIDE_FROM_ABI constexpr void swap(const tuple& __t) const1013 noexcept(__all<is_nothrow_swappable_v<const _Tp&>...>::value) {1014 __base_.swap(__t.__base_);1015 }1016 1017 template <__tuple_like_no_tuple _UTuple>1018# if _LIBCPP_STD_VER >= 261019 requires __can_tuple_compare_equal<tuple, _UTuple> && (sizeof...(_Tp) == tuple_size_v<_UTuple>)1020# endif // _LIBCPP_STD_VER >= 261021 _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const tuple& __x, const _UTuple& __y) {1022 static_assert(sizeof...(_Tp) == tuple_size_v<_UTuple>, "Can't compare tuple-like values of different sizes");1023 return std::__tuple_compare_equal<sizeof...(_Tp)>(__x, __y);1024 }1025 1026 template <__tuple_like_no_tuple _UTuple>1027 requires(sizeof...(_Tp) == tuple_size_v<_UTuple>)1028 _LIBCPP_HIDE_FROM_ABI friend constexpr __tuple_common_comparison_category<tuple, _UTuple>1029 operator<=>(const tuple& __x, const _UTuple& __y) {1030 return std::__tuple_compare_three_way<__tuple_common_comparison_category<tuple, _UTuple>>(1031 __x, __y, index_sequence_for<_Tp...>{});1032 }1033# endif // _LIBCPP_STD_VER >= 231034};1035 1036_LIBCPP_DIAGNOSTIC_PUSH1037# if __has_warning("-Winvalid-specialization")1038_LIBCPP_CLANG_DIAGNOSTIC_IGNORED("-Winvalid-specialization")1039# endif1040template <>1041class tuple<> {1042public:1043 constexpr tuple() _NOEXCEPT = default;1044 template <class _Alloc>1045 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple(allocator_arg_t, const _Alloc&) _NOEXCEPT {}1046 template <class _Alloc>1047 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple(allocator_arg_t, const _Alloc&, const tuple&) _NOEXCEPT {}1048 template <class _Up>1049 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple(array<_Up, 0>) _NOEXCEPT {}1050 template <class _Alloc, class _Up>1051 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 tuple(allocator_arg_t, const _Alloc&, array<_Up, 0>) _NOEXCEPT {}1052 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void swap(tuple&) _NOEXCEPT {}1053# if _LIBCPP_STD_VER >= 231054 _LIBCPP_HIDE_FROM_ABI constexpr void swap(const tuple&) const noexcept {}1055 1056 template <__tuple_like_no_tuple _UTuple>1057# if _LIBCPP_STD_VER >= 261058 requires(tuple_size_v<_UTuple> == 0)1059# endif // _LIBCPP_STD_VER >= 261060 _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const tuple&, const _UTuple&) {1061 static_assert(tuple_size_v<_UTuple> == 0, "Can't compare tuple-like values of different sizes");1062 return true;1063 }1064 1065 template <__tuple_like_no_tuple _UTuple>1066 requires(tuple_size_v<_UTuple> == 0)1067 _LIBCPP_HIDE_FROM_ABI friend constexpr strong_ordering operator<=>(const tuple&, const _UTuple&) {1068 return strong_ordering::equal;1069 }1070# endif1071};1072_LIBCPP_DIAGNOSTIC_POP1073 1074# if _LIBCPP_STD_VER >= 231075template <class... _TTypes, class... _UTypes, template <class> class _TQual, template <class> class _UQual>1076 requires requires { typename tuple<common_reference_t<_TQual<_TTypes>, _UQual<_UTypes>>...>; }1077struct basic_common_reference<tuple<_TTypes...>, tuple<_UTypes...>, _TQual, _UQual> {1078 using type _LIBCPP_NODEBUG = tuple<common_reference_t<_TQual<_TTypes>, _UQual<_UTypes>>...>;1079};1080 1081template <class... _TTypes, class... _UTypes>1082 requires requires { typename tuple<common_type_t<_TTypes, _UTypes>...>; }1083struct common_type<tuple<_TTypes...>, tuple<_UTypes...>> {1084 using type _LIBCPP_NODEBUG = tuple<common_type_t<_TTypes, _UTypes>...>;1085};1086# endif // _LIBCPP_STD_VER >= 231087 1088# if _LIBCPP_STD_VER >= 171089template <class... _Tp>1090tuple(_Tp...) -> tuple<_Tp...>;1091template <class _Tp1, class _Tp2>1092tuple(pair<_Tp1, _Tp2>) -> tuple<_Tp1, _Tp2>;1093template <class _Alloc, class... _Tp>1094tuple(allocator_arg_t, _Alloc, _Tp...) -> tuple<_Tp...>;1095template <class _Alloc, class _Tp1, class _Tp2>1096tuple(allocator_arg_t, _Alloc, pair<_Tp1, _Tp2>) -> tuple<_Tp1, _Tp2>;1097template <class _Alloc, class... _Tp>1098tuple(allocator_arg_t, _Alloc, tuple<_Tp...>) -> tuple<_Tp...>;1099# endif1100 1101template <class... _Tp, __enable_if_t<__all<__is_swappable_v<_Tp>...>::value, int> = 0>1102inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 void1103swap(tuple<_Tp...>& __t, tuple<_Tp...>& __u) noexcept(__all<__is_nothrow_swappable_v<_Tp>...>::value) {1104 __t.swap(__u);1105}1106 1107# if _LIBCPP_STD_VER >= 231108template <class... _Tp>1109_LIBCPP_HIDE_FROM_ABI constexpr enable_if_t<__all<is_swappable_v<const _Tp>...>::value, void>1110swap(const tuple<_Tp...>& __lhs,1111 const tuple<_Tp...>& __rhs) noexcept(__all<is_nothrow_swappable_v<const _Tp>...>::value) {1112 __lhs.swap(__rhs);1113}1114# endif1115 1116// get1117 1118template <size_t _Ip, class... _Tp>1119inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Ip, tuple<_Tp...> >::type&1120get(tuple<_Tp...>& __t) _NOEXCEPT {1121 using type _LIBCPP_NODEBUG = typename tuple_element<_Ip, tuple<_Tp...> >::type;1122 return static_cast<__tuple_leaf<_Ip, type>&>(__t.__base_).get();1123}1124 1125template <size_t _Ip, class... _Tp>1126inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Ip, tuple<_Tp...> >::type&1127get(const tuple<_Tp...>& __t) _NOEXCEPT {1128 using type _LIBCPP_NODEBUG = typename tuple_element<_Ip, tuple<_Tp...> >::type;1129 return static_cast<const __tuple_leaf<_Ip, type>&>(__t.__base_).get();1130}1131 1132template <size_t _Ip, class... _Tp>1133inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 typename tuple_element<_Ip, tuple<_Tp...> >::type&&1134get(tuple<_Tp...>&& __t) _NOEXCEPT {1135 using type _LIBCPP_NODEBUG = typename tuple_element<_Ip, tuple<_Tp...> >::type;1136 return static_cast<type&&>(static_cast<__tuple_leaf<_Ip, type>&&>(__t.__base_).get());1137}1138 1139template <size_t _Ip, class... _Tp>1140inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 const typename tuple_element<_Ip, tuple<_Tp...> >::type&&1141get(const tuple<_Tp...>&& __t) _NOEXCEPT {1142 using type _LIBCPP_NODEBUG = typename tuple_element<_Ip, tuple<_Tp...> >::type;1143 return static_cast<const type&&>(static_cast<const __tuple_leaf<_Ip, type>&&>(__t.__base_).get());1144}1145 1146# if _LIBCPP_STD_VER >= 141147 1148template <class _T1, class... _Args>1149inline _LIBCPP_HIDE_FROM_ABI constexpr _T1& get(tuple<_Args...>& __tup) noexcept {1150 return std::get<__find_exactly_one_t<_T1, _Args...>::value>(__tup);1151}1152 1153template <class _T1, class... _Args>1154inline _LIBCPP_HIDE_FROM_ABI constexpr _T1 const& get(tuple<_Args...> const& __tup) noexcept {1155 return std::get<__find_exactly_one_t<_T1, _Args...>::value>(__tup);1156}1157 1158template <class _T1, class... _Args>1159inline _LIBCPP_HIDE_FROM_ABI constexpr _T1&& get(tuple<_Args...>&& __tup) noexcept {1160 return std::get<__find_exactly_one_t<_T1, _Args...>::value>(std::move(__tup));1161}1162 1163template <class _T1, class... _Args>1164inline _LIBCPP_HIDE_FROM_ABI constexpr _T1 const&& get(tuple<_Args...> const&& __tup) noexcept {1165 return std::get<__find_exactly_one_t<_T1, _Args...>::value>(std::move(__tup));1166}1167 1168# endif1169 1170// tie1171 1172template <class... _Tp>1173inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 tuple<_Tp&...> tie(_Tp&... __t) _NOEXCEPT {1174 return tuple<_Tp&...>(__t...);1175}1176 1177template <class... _Tp>1178inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 tuple<__unwrap_ref_decay_t<_Tp>...>1179make_tuple(_Tp&&... __t) {1180 return tuple<__unwrap_ref_decay_t<_Tp>...>(std::forward<_Tp>(__t)...);1181}1182 1183template <class... _Tp>1184inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 tuple<_Tp&&...> forward_as_tuple(_Tp&&... __t) _NOEXCEPT {1185 return tuple<_Tp&&...>(std::forward<_Tp>(__t)...);1186}1187 1188template <class... _Tp, class... _Up>1189# if _LIBCPP_STD_VER >= 261190 requires(__all<requires(const _Tp& __t, const _Up& __u) {1191 { __t == __u } -> __boolean_testable;1192 }...>::value && (sizeof...(_Tp) == sizeof...(_Up)))1193# endif1194inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool1195operator==(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {1196 static_assert(sizeof...(_Tp) == sizeof...(_Up), "Can't compare tuples of different sizes");1197 return std::__tuple_compare_equal<sizeof...(_Tp)>(__x, __y);1198}1199 1200# if _LIBCPP_STD_VER >= 201201 1202// operator<=>1203 1204template <class... _Tp, class... _Up>1205 requires(sizeof...(_Tp) == sizeof...(_Up))1206_LIBCPP_HIDE_FROM_ABI constexpr common_comparison_category_t<__synth_three_way_result<_Tp, _Up>...>1207operator<=>(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {1208 return std::__tuple_compare_three_way<common_comparison_category_t<__synth_three_way_result<_Tp, _Up>...>>(1209 __x, __y, index_sequence_for<_Tp...>{});1210}1211 1212# else // _LIBCPP_STD_VER >= 201213 1214template <class... _Tp, class... _Up>1215inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool1216operator!=(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {1217 return !(__x == __y);1218}1219 1220template <size_t _Ip>1221struct __tuple_less {1222 template <class _Tp, class _Up>1223 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator()(const _Tp& __x, const _Up& __y) {1224 const size_t __idx = tuple_size<_Tp>::value - _Ip;1225 if (std::get<__idx>(__x) < std::get<__idx>(__y))1226 return true;1227 if (std::get<__idx>(__y) < std::get<__idx>(__x))1228 return false;1229 return __tuple_less<_Ip - 1>()(__x, __y);1230 }1231};1232 1233template <>1234struct __tuple_less<0> {1235 template <class _Tp, class _Up>1236 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool operator()(const _Tp&, const _Up&) {1237 return false;1238 }1239};1240 1241template <class... _Tp, class... _Up>1242inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool1243operator<(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {1244 static_assert(sizeof...(_Tp) == sizeof...(_Up), "Can't compare tuples of different sizes");1245 return __tuple_less<sizeof...(_Tp)>()(__x, __y);1246}1247 1248template <class... _Tp, class... _Up>1249inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool1250operator>(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {1251 return __y < __x;1252}1253 1254template <class... _Tp, class... _Up>1255inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool1256operator>=(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {1257 return !(__x < __y);1258}1259 1260template <class... _Tp, class... _Up>1261inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 bool1262operator<=(const tuple<_Tp...>& __x, const tuple<_Up...>& __y) {1263 return !(__y < __x);1264}1265 1266# endif // _LIBCPP_STD_VER >= 201267 1268// tuple_cat1269 1270template <class... _Tuples>1271struct __tuple_cat_return_impl;1272 1273template <class... _Types>1274struct __tuple_cat_return_impl<tuple<_Types...>> {1275 using type _LIBCPP_NODEBUG = tuple<_Types...>;1276};1277 1278template <class... _Types0, class... _Types1, class... _Tuples>1279struct __tuple_cat_return_impl<tuple<_Types0...>, tuple<_Types1...>, _Tuples...>1280 : __tuple_cat_return_impl<tuple<_Types0..., _Types1...>, _Tuples...> {};1281 1282template <class... _Types0, class _Tp, class _Up, class... _Tuples>1283struct __tuple_cat_return_impl<tuple<_Types0...>, pair<_Tp, _Up>, _Tuples...>1284 : __tuple_cat_return_impl<tuple<_Types0..., _Tp, _Up>, _Tuples...> {};1285 1286template <class, class, class>1287struct __tuple_cat_array;1288 1289template <class... _Types, class _ValueT, size_t... _Indices>1290struct __tuple_cat_array<tuple<_Types...>, _ValueT, __index_sequence<_Indices...>> {1291 template <size_t>1292 using __value_type _LIBCPP_NODEBUG = _ValueT;1293 1294 using type _LIBCPP_NODEBUG = tuple<_Types..., __value_type<_Indices>...>;1295};1296 1297template <class... _Types, class _ValueT, size_t _Np, class... _Tuples>1298struct __tuple_cat_return_impl<tuple<_Types...>, array<_ValueT, _Np>, _Tuples...>1299 : __tuple_cat_return_impl<typename __tuple_cat_array<tuple<_Types...>, _ValueT, __make_index_sequence<_Np>>::type,1300 _Tuples...> {};1301 1302template <class... _Tuples>1303using __tuple_cat_return_t _LIBCPP_NODEBUG =1304 typename __tuple_cat_return_impl<tuple<>, __remove_cvref_t<_Tuples>...>::type;1305 1306inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 tuple<> tuple_cat() { return tuple<>(); }1307 1308template <class _Rp, class _Indices, class _Tuple0, class... _Tuples>1309struct __tuple_cat_return_ref_imp;1310 1311template <class... _Types, size_t... _I0, class _Tuple0>1312struct __tuple_cat_return_ref_imp<tuple<_Types...>, __index_sequence<_I0...>, _Tuple0> {1313 using _T0 _LIBCPP_NODEBUG = __libcpp_remove_reference_t<_Tuple0>;1314 typedef tuple<_Types..., __copy_cvref_t<_Tuple0, typename tuple_element<_I0, _T0>::type>&&...> type;1315};1316 1317template <class... _Types, size_t... _I0, class _Tuple0, class _Tuple1, class... _Tuples>1318struct __tuple_cat_return_ref_imp<tuple<_Types...>, __index_sequence<_I0...>, _Tuple0, _Tuple1, _Tuples...>1319 : public __tuple_cat_return_ref_imp<1320 tuple<_Types...,1321 __copy_cvref_t<_Tuple0, typename tuple_element<_I0, __libcpp_remove_reference_t<_Tuple0>>::type>&&...>,1322 __make_index_sequence<tuple_size<__libcpp_remove_reference_t<_Tuple1> >::value>,1323 _Tuple1,1324 _Tuples...> {};1325 1326template <class _Tuple0, class... _Tuples>1327struct __tuple_cat_return_ref1328 : public __tuple_cat_return_ref_imp<1329 tuple<>,1330 __make_index_sequence< tuple_size<__libcpp_remove_reference_t<_Tuple0> >::value >,1331 _Tuple0,1332 _Tuples...> {};1333 1334template <class _Types, class _I0, class _J0>1335struct __tuple_cat;1336 1337template <class... _Types, size_t... _I0, size_t... _J0>1338struct __tuple_cat<tuple<_Types...>, __index_sequence<_I0...>, __index_sequence<_J0...>> {1339 template <class _Tuple0>1340 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX141341 typename __tuple_cat_return_ref<tuple<_Types...>&&, _Tuple0&&>::type1342 operator()(tuple<_Types...> __t, _Tuple0&& __t0) {1343 (void)__t; // avoid unused parameter warning on GCC when _I0 is empty1344 return std::forward_as_tuple(1345 std::forward<_Types>(std::get<_I0>(__t))..., std::get<_J0>(std::forward<_Tuple0>(__t0))...);1346 }1347 1348 template <class _Tuple0, class _Tuple1, class... _Tuples>1349 _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX141350 typename __tuple_cat_return_ref<tuple<_Types...>&&, _Tuple0&&, _Tuple1&&, _Tuples&&...>::type1351 operator()(tuple<_Types...> __t, _Tuple0&& __t0, _Tuple1&& __t1, _Tuples&&... __tpls) {1352 (void)__t; // avoid unused parameter warning on GCC when _I0 is empty1353 using _T0 _LIBCPP_NODEBUG = __libcpp_remove_reference_t<_Tuple0>;1354 using _T1 _LIBCPP_NODEBUG = __libcpp_remove_reference_t<_Tuple1>;1355 return __tuple_cat<tuple<_Types..., __copy_cvref_t<_Tuple0, typename tuple_element<_J0, _T0>::type>&&...>,1356 __make_index_sequence<sizeof...(_Types) + tuple_size<_T0>::value>,1357 __make_index_sequence<tuple_size<_T1>::value>>()(1358 std::forward_as_tuple(1359 std::forward<_Types>(std::get<_I0>(__t))..., std::get<_J0>(std::forward<_Tuple0>(__t0))...),1360 std::forward<_Tuple1>(__t1),1361 std::forward<_Tuples>(__tpls)...);1362 }1363};1364 1365template <class _TupleDst, class _TupleSrc, size_t... _Indices>1366inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _TupleDst1367__tuple_cat_select_element_wise(_TupleSrc&& __src, __index_sequence<_Indices...>) {1368 static_assert(tuple_size<_TupleDst>::value == tuple_size<_TupleSrc>::value,1369 "misuse of __tuple_cat_select_element_wise with tuples of different sizes");1370 return _TupleDst(std::get<_Indices>(std::forward<_TupleSrc>(__src))...);1371}1372 1373template <class _Tuple0, class... _Tuples>1374inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __tuple_cat_return_t<_Tuple0, _Tuples...>1375tuple_cat(_Tuple0&& __t0, _Tuples&&... __tpls) {1376 using _T0 _LIBCPP_NODEBUG = __libcpp_remove_reference_t<_Tuple0>;1377 using _TRet _LIBCPP_NODEBUG = __tuple_cat_return_t<_Tuple0, _Tuples...>;1378 using _T0Indices _LIBCPP_NODEBUG = __make_index_sequence<tuple_size<_T0>::value>;1379 using _TRetIndices _LIBCPP_NODEBUG = __make_index_sequence<tuple_size<_TRet>::value>;1380 return std::__tuple_cat_select_element_wise<_TRet>(1381 __tuple_cat<tuple<>, __index_sequence<>, _T0Indices>()(1382 tuple<>(), std::forward<_Tuple0>(__t0), std::forward<_Tuples>(__tpls)...),1383 _TRetIndices());1384}1385 1386template <class... _Tp, class _Alloc>1387struct uses_allocator<tuple<_Tp...>, _Alloc> : true_type {};1388 1389# if _LIBCPP_STD_VER >= 171390# define _LIBCPP_NOEXCEPT_RETURN(...) \1391 noexcept(noexcept(__VA_ARGS__)) { return __VA_ARGS__; }1392 1393// The _LIBCPP_NOEXCEPT_RETURN macro breaks formatting.1394// clang-format off1395template <class _Fn, class _Tuple, size_t... _Id>1396inline _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto)1397__apply_tuple_impl(_Fn&& __f, _Tuple&& __t, index_sequence<_Id...>)1398 _LIBCPP_NOEXCEPT_RETURN(std::__invoke(std::forward<_Fn>(__f), std::get<_Id>(std::forward<_Tuple>(__t))...))1399 1400template <class _Fn, class _Tuple>1401inline _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) apply(_Fn&& __f, _Tuple&& __t)1402 _LIBCPP_NOEXCEPT_RETURN(std::__apply_tuple_impl(1403 std::forward<_Fn>(__f),1404 std::forward<_Tuple>(__t),1405 make_index_sequence<tuple_size_v<remove_reference_t<_Tuple>>>()))1406 1407#if _LIBCPP_STD_VER >= 201408template <class _Tp, class _Tuple, size_t... _Idx>1409inline _LIBCPP_HIDE_FROM_ABI constexpr _Tp __make_from_tuple_impl(_Tuple&& __t, index_sequence<_Idx...>)1410 noexcept(noexcept(_Tp(std::get<_Idx>(std::forward<_Tuple>(__t))...)))1411 requires is_constructible_v<_Tp, decltype(std::get<_Idx>(std::forward<_Tuple>(__t)))...> {1412 return _Tp(std::get<_Idx>(std::forward<_Tuple>(__t))...);1413}1414#else1415template <class _Tp, class _Tuple, size_t... _Idx>1416inline _LIBCPP_HIDE_FROM_ABI constexpr _Tp __make_from_tuple_impl(_Tuple&& __t, index_sequence<_Idx...>,1417 enable_if_t<is_constructible_v<_Tp, decltype(std::get<_Idx>(std::forward<_Tuple>(__t)))...>> * = nullptr)1418 _LIBCPP_NOEXCEPT_RETURN(_Tp(std::get<_Idx>(std::forward<_Tuple>(__t))...))1419#endif // _LIBCPP_STD_VER >= 201420#undef _LIBCPP_NOEXCEPT_RETURN1421 1422template <class _Tp, class _Tuple,1423 class _Seq = make_index_sequence<tuple_size_v<remove_reference_t<_Tuple>>>, class = void>1424inline constexpr bool __can_make_from_tuple = false;1425 1426template <class _Tp, class _Tuple, size_t... _Idx>1427inline constexpr bool __can_make_from_tuple<_Tp, _Tuple, index_sequence<_Idx...>,1428 enable_if_t<is_constructible_v<_Tp, decltype(std::get<_Idx>(std::declval<_Tuple>()))...>>> = true;1429 1430// Based on LWG3528(https://wg21.link/LWG3528) and http://eel.is/c++draft/description#structure.requirements-9,1431// the standard allows to impose requirements, we constraint std::make_from_tuple to make std::make_from_tuple1432// SFINAE friendly and also avoid worse diagnostic messages. We still keep the constraints of std::__make_from_tuple_impl1433// so that std::__make_from_tuple_impl will have the same advantages when used alone.1434#if _LIBCPP_STD_VER >= 201435template <class _Tp, class _Tuple>1436 requires __can_make_from_tuple<_Tp, _Tuple> // strengthen1437#else1438template <class _Tp, class _Tuple, class = enable_if_t<__can_make_from_tuple<_Tp, _Tuple>>> // strengthen1439#endif // _LIBCPP_STD_VER >= 201440 1441inline _LIBCPP_HIDE_FROM_ABI constexpr _Tp make_from_tuple(_Tuple&& __t)1442 noexcept(noexcept(std::__make_from_tuple_impl<_Tp>(std::forward<_Tuple>(__t),1443 make_index_sequence<tuple_size_v<remove_reference_t<_Tuple>>>()))) {1444#if _LIBCPP_STD_VER >= 231445 if constexpr (tuple_size_v<remove_reference_t<_Tuple>> == 1) {1446 static_assert(!std::reference_constructs_from_temporary_v<_Tp, decltype(std::get<0>(std::declval<_Tuple>()))>,1447 "Attempted construction of reference element binds to a temporary whose lifetime has ended");1448 }1449#endif // _LIBCPP_STD_VER >= 231450 return std::__make_from_tuple_impl<_Tp>(1451 std::forward<_Tuple>(__t), make_index_sequence<tuple_size_v<remove_reference_t<_Tuple>>>());1452}1453 1454# endif // _LIBCPP_STD_VER >= 171455 1456#endif // !defined(_LIBCPP_CXX03_LANG)1457 1458_LIBCPP_END_NAMESPACE_STD1459 1460_LIBCPP_POP_MACROS1461 1462// clang-format on1463 1464# if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 201465# include <cstddef>1466# include <exception>1467# include <iosfwd>1468# include <new>1469# include <type_traits>1470# include <typeinfo>1471# include <utility>1472# endif1473#endif // __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)1474 1475#endif // _LIBCPP_TUPLE1476