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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_UTILITY11#define _LIBCPP_UTILITY12 13/*14 utility synopsis15 16#include <initializer_list>17 18namespace std19{20 21template <class T>22 void23 swap(T& a, T& b);24 25namespace rel_ops26{27 template<class T> bool operator!=(const T&, const T&);28 template<class T> bool operator> (const T&, const T&);29 template<class T> bool operator<=(const T&, const T&);30 template<class T> bool operator>=(const T&, const T&);31}32 33template<class T>34void35swap(T& a, T& b) noexcept(is_nothrow_move_constructible<T>::value &&36 is_nothrow_move_assignable<T>::value);37 38template <class T, size_t N>39void40swap(T (&a)[N], T (&b)[N]) noexcept(noexcept(swap(*a, *b)));41 42template <class T> T&& forward(typename remove_reference<T>::type& t) noexcept; // constexpr in C++1443template <class T> T&& forward(typename remove_reference<T>::type&& t) noexcept; // constexpr in C++1444 45template <typename T>46[[nodiscard]] constexpr47auto forward_like(auto&& x) noexcept -> see below; // since C++2348 49template <class T> typename remove_reference<T>::type&& move(T&&) noexcept; // constexpr in C++1450 51template <class T>52 typename conditional53 <54 !is_nothrow_move_constructible<T>::value && is_copy_constructible<T>::value,55 const T&,56 T&&57 >::type58 move_if_noexcept(T& x) noexcept; // constexpr in C++1459 60template <class T> constexpr add_const_t<T>& as_const(T& t) noexcept; // C++1761template <class T> void as_const(const T&&) = delete; // C++1762 63template <class T> typename add_rvalue_reference<T>::type declval() noexcept;64 65template<class T, class U> constexpr bool cmp_equal(T t, U u) noexcept; // C++2066template<class T, class U> constexpr bool cmp_not_equal(T t, U u) noexcept; // C++2067template<class T, class U> constexpr bool cmp_less(T t, U u) noexcept; // C++2068template<class T, class U> constexpr bool cmp_greater(T t, U u) noexcept; // C++2069template<class T, class U> constexpr bool cmp_less_equal(T t, U u) noexcept; // C++2070template<class T, class U> constexpr bool cmp_greater_equal(T t, U u) noexcept; // C++2071template<class R, class T> constexpr bool in_range(T t) noexcept; // C++2072 73template <class T1, class T2>74struct pair75{76 typedef T1 first_type;77 typedef T2 second_type;78 79 T1 first;80 T2 second;81 82 pair(const pair&) = default;83 pair(pair&&) = default;84 explicit(see-below) constexpr pair();85 explicit(see-below) pair(const T1& x, const T2& y); // constexpr in C++1486 template <class U = T1, class V = T2> explicit(see-below) pair(U&&, V&&); // constexpr in C++1487 template <class U, class V> constexpr explicit(see-below) pair(pair<U, V>&); // since C++2388 template <class U, class V> explicit(see-below) pair(const pair<U, V>& p); // constexpr in C++1489 template <class U, class V> explicit(see-below) pair(pair<U, V>&& p); // constexpr in C++1490 template <class U, class V>91 constexpr explicit(see-below) pair(const pair<U, V>&&); // since C++2392 template <pair-like P> constexpr explicit(see-below) pair(P&&); // since C++2393 template <class... Args1, class... Args2>94 pair(piecewise_construct_t, tuple<Args1...> first_args, // constexpr in C++2095 tuple<Args2...> second_args);96 97 constexpr const pair& operator=(const pair& p) const; // since C++2398 template <class U, class V> pair& operator=(const pair<U, V>& p); // constexpr in C++2099 template <class U, class V>100 constexpr const pair& operator=(const pair<U, V>& p) const; // since C++23101 pair& operator=(pair&& p) noexcept(is_nothrow_move_assignable<T1>::value &&102 is_nothrow_move_assignable<T2>::value); // constexpr in C++20103 constexpr const pair& operator=(pair&& p) const; // since C++23104 template <class U, class V> pair& operator=(pair<U, V>&& p); // constexpr in C++20105 template <class U, class V>106 constexpr const pair& operator=(pair<U, V>&& p) const; // since C++23107 template <pair-like P> constexpr pair& operator=(P&&); // since C++23108 template <pair-like P> constexpr const pair& operator=(P&&) const; // since C++23109 110 void swap(pair& p) noexcept(is_nothrow_swappable_v<T1> &&111 is_nothrow_swappable_v<T2>); // constexpr in C++20112 constexpr void swap(const pair& p) const noexcept(see below); // since C++23113};114 115template<class T1, class T2, class U1, class U2, template<class> class TQual, template<class> class UQual>116struct basic_common_reference<pair<T1, T2>, pair<U1, U2>, TQual, UQual>; // since C++23117 118template<class T1, class T2, class U1, class U2>119struct common_type<pair<T1, T2>, pair<U1, U2>>; // since C++23120 121template<class T1, class T2> pair(T1, T2) -> pair<T1, T2>;122 123template <class T1, class T2, class U1, class U2>124bool operator==(const pair<T1,T2>&, const pair<U1,U2>&); // constexpr in C++14125template <class T1, class T2, class U1, class U2>126bool operator!=(const pair<T1,T2>&, const pair<U1,U2>&); // constexpr in C++14, removed in C++20127template <class T1, class T2, class U1, class U2>128bool operator< (const pair<T1,T2>&, const pair<U1,U2>&); // constexpr in C++14, removed in C++20129template <class T1, class T2, class U1, class U2>130bool operator> (const pair<T1,T2>&, const pair<U1,U2>&); // constexpr in C++14, removed in C++20131template <class T1, class T2, class U1, class U2>132bool operator>=(const pair<T1,T2>&, const pair<U1,U2>&); // constexpr in C++14, removed in C++20133template <class T1, class T2, class U1, class U2>134bool operator<=(const pair<T1,T2>&, const pair<U1,U2>&); // constexpr in C++14, removed in C++20135template <class T1, class T2, class U1, class U2>136 constexpr common_comparison_type_t<synth-three-way-result<T1,U1>,137 synth-three-way-result<T2,U2>>138 operator<=>(const pair<T1,T2>&, const pair<U1,U2>&); // C++20139 140template <class T1, class T2> pair<V1, V2> make_pair(T1&&, T2&&); // constexpr in C++14141template <class T1, class T2>142void143swap(pair<T1, T2>& x, pair<T1, T2>& y) noexcept(noexcept(x.swap(y))); // constexpr in C++20144 145template<class T1, class T2> // since C++23146constexpr void swap(const pair<T1, T2>& x, const pair<T1, T2>& y) noexcept(noexcept(x.swap(y)));147 148struct piecewise_construct_t { explicit piecewise_construct_t() = default; };149inline constexpr piecewise_construct_t piecewise_construct = piecewise_construct_t();150 151template <class T> struct tuple_size;152template <size_t I, class T> struct tuple_element;153 154template <class T1, class T2> struct tuple_size<pair<T1, T2> >;155template <class T1, class T2> struct tuple_element<0, pair<T1, T2> >;156template <class T1, class T2> struct tuple_element<1, pair<T1, T2> >;157 158template<size_t I, class T1, class T2>159 typename tuple_element<I, pair<T1, T2> >::type&160 get(pair<T1, T2>&) noexcept; // constexpr in C++14161 162template<size_t I, class T1, class T2>163 const typename tuple_element<I, pair<T1, T2> >::type&164 get(const pair<T1, T2>&) noexcept; // constexpr in C++14165 166template<size_t I, class T1, class T2>167 typename tuple_element<I, pair<T1, T2> >::type&&168 get(pair<T1, T2>&&) noexcept; // constexpr in C++14169 170template<size_t I, class T1, class T2>171 const typename tuple_element<I, pair<T1, T2> >::type&&172 get(const pair<T1, T2>&&) noexcept; // constexpr in C++14173 174template<class T1, class T2>175 constexpr T1& get(pair<T1, T2>&) noexcept; // C++14176 177template<class T1, class T2>178 constexpr const T1& get(const pair<T1, T2>&) noexcept; // C++14179 180template<class T1, class T2>181 constexpr T1&& get(pair<T1, T2>&&) noexcept; // C++14182 183template<class T1, class T2>184 constexpr const T1&& get(const pair<T1, T2>&&) noexcept; // C++14185 186template<class T1, class T2>187 constexpr T1& get(pair<T2, T1>&) noexcept; // C++14188 189template<class T1, class T2>190 constexpr const T1& get(const pair<T2, T1>&) noexcept; // C++14191 192template<class T1, class T2>193 constexpr T1&& get(pair<T2, T1>&&) noexcept; // C++14194 195template<class T1, class T2>196 constexpr const T1&& get(const pair<T2, T1>&&) noexcept; // C++14197 198// C++14199 200template<class T, T... I>201struct integer_sequence202{203 typedef T value_type;204 205 static constexpr size_t size() noexcept;206};207 208template<size_t... I>209 using index_sequence = integer_sequence<size_t, I...>;210 211template<class T, T N>212 using make_integer_sequence = integer_sequence<T, 0, 1, ..., N-1>;213template<size_t N>214 using make_index_sequence = make_integer_sequence<size_t, N>;215 216template<class... T>217 using index_sequence_for = make_index_sequence<sizeof...(T)>;218 219template<class T, class U=T>220 constexpr T exchange(T& obj, U&& new_value) // constexpr in C++17, noexcept in C++23221 noexcept(is_nothrow_move_constructible<T>::value && is_nothrow_assignable<T&, U>::value);222 223// 20.2.7, in-place construction // C++17224struct in_place_t {225 explicit in_place_t() = default;226};227inline constexpr in_place_t in_place{};228template <class T>229 struct in_place_type_t {230 explicit in_place_type_t() = default;231 };232template <class T>233 inline constexpr in_place_type_t<T> in_place_type{};234template <size_t I>235 struct in_place_index_t {236 explicit in_place_index_t() = default;237 };238template <size_t I>239 inline constexpr in_place_index_t<I> in_place_index{};240 241// [utility.underlying], to_underlying242template <class T>243 constexpr underlying_type_t<T> to_underlying( T value ) noexcept; // C++23244 245} // std246 247*/248 249#if __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)250# include <__cxx03/utility>251#else252# include <__config>253 254# include <__utility/declval.h>255# include <__utility/forward.h>256# include <__utility/move.h>257# include <__utility/pair.h>258# include <__utility/piecewise_construct.h>259# include <__utility/rel_ops.h>260# include <__utility/swap.h>261 262# if _LIBCPP_STD_VER >= 14263# include <__utility/exchange.h>264# include <__utility/integer_sequence.h>265# endif266 267# if _LIBCPP_STD_VER >= 17268# include <__utility/as_const.h>269# include <__utility/in_place.h>270# endif271 272# if _LIBCPP_STD_VER >= 20273# include <__utility/cmp.h>274# endif275 276# if _LIBCPP_STD_VER >= 23277# include <__utility/forward_like.h>278# include <__utility/to_underlying.h>279# include <__utility/unreachable.h>280# endif281 282# if _LIBCPP_STD_VER >= 26283# include <__variant/monostate.h>284# endif285 286# include <version>287 288// standard-mandated includes289 290// [utility.syn]291# include <compare>292# include <initializer_list>293 294// [tuple.creation]295 296# include <__tuple/ignore.h>297 298// [tuple.helper]299# include <__tuple/tuple_element.h>300# include <__tuple/tuple_size.h>301 302# if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)303# pragma GCC system_header304# endif305 306# if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20307# include <limits>308# endif309 310# if !defined(_LIBCPP_REMOVE_TRANSITIVE_INCLUDES) && _LIBCPP_STD_VER <= 20311# include <cstddef>312# include <cstdlib>313# include <iosfwd>314# include <type_traits>315# endif316#endif // __cplusplus < 201103L && defined(_LIBCPP_USE_FROZEN_CXX03_HEADERS)317 318#endif // _LIBCPP_UTILITY319