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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___FLAT_SET_RA_ITERATOR_H11#define _LIBCPP___FLAT_SET_RA_ITERATOR_H12 13#include "__type_traits/is_same.h"14#include <__compare/three_way_comparable.h>15#include <__config>16#include <__iterator/incrementable_traits.h>17#include <__iterator/iterator_traits.h>18#include <__type_traits/is_constructible.h>19#include <__utility/move.h>20 21#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)22# pragma GCC system_header23#endif24 25_LIBCPP_PUSH_MACROS26#include <__undef_macros>27 28#if _LIBCPP_STD_VER >= 2329 30_LIBCPP_BEGIN_NAMESPACE_STD31 32/**33 * __ra_iterator is a random access iterator that wraps an underlying iterator.34 * It also stores the underlying container type in its type so that algorithms35 * can optimize based on the underlying container type, and to avoid inadvertently36 * mixing iterators coming from different containers..37 */38template <class _Container, class _Iterator>39struct __ra_iterator {40private:41 _Iterator __iter_;42 43 friend _Container;44 45 // note: checking the concept random_access_iterator does not work for incomplete types46 static_assert(_IsSame<typename iterator_traits<_Iterator>::iterator_category, random_access_iterator_tag>::value,47 "Underlying iterator must be a random access iterator");48 49public:50 using iterator_concept = random_access_iterator_tag; // deliberately lower contiguous_iterator51 using iterator_category = random_access_iterator_tag;52 using value_type = iter_value_t<_Iterator>;53 using difference_type = iter_difference_t<_Iterator>;54 55 _LIBCPP_HIDE_FROM_ABI __ra_iterator()56 requires is_default_constructible_v<_Iterator>57 = default;58 59 _LIBCPP_HIDE_FROM_ABI explicit constexpr __ra_iterator(_Iterator __iter) : __iter_(std::move(__iter)) {}60 61 _LIBCPP_HIDE_FROM_ABI constexpr _Iterator __base() const noexcept(noexcept(_Iterator(__iter_))) { return __iter_; }62 63 _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator*() const { return *__iter_; }64 _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator->() const65 requires requires { __iter_.operator->(); }66 {67 return __iter_.operator->();68 }69 70 _LIBCPP_HIDE_FROM_ABI constexpr __ra_iterator& operator++() {71 ++__iter_;72 return *this;73 }74 75 _LIBCPP_HIDE_FROM_ABI constexpr __ra_iterator operator++(int) {76 __ra_iterator __tmp(*this);77 ++*this;78 return __tmp;79 }80 81 _LIBCPP_HIDE_FROM_ABI constexpr __ra_iterator& operator--() {82 --__iter_;83 return *this;84 }85 86 _LIBCPP_HIDE_FROM_ABI constexpr __ra_iterator operator--(int) {87 __ra_iterator __tmp(*this);88 --*this;89 return __tmp;90 }91 92 _LIBCPP_HIDE_FROM_ABI constexpr __ra_iterator& operator+=(difference_type __x) {93 __iter_ += __x;94 return *this;95 }96 97 _LIBCPP_HIDE_FROM_ABI constexpr __ra_iterator& operator-=(difference_type __x) {98 __iter_ -= __x;99 return *this;100 }101 102 _LIBCPP_HIDE_FROM_ABI constexpr decltype(auto) operator[](difference_type __n) const { return *(*this + __n); }103 104 _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator==(const __ra_iterator& __x, const __ra_iterator& __y) {105 return __x.__iter_ == __y.__iter_;106 }107 108 _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<(const __ra_iterator& __x, const __ra_iterator& __y) {109 return __x.__iter_ < __y.__iter_;110 }111 112 _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>(const __ra_iterator& __x, const __ra_iterator& __y) {113 return __y < __x;114 }115 116 _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator<=(const __ra_iterator& __x, const __ra_iterator& __y) {117 return !(__y < __x);118 }119 120 _LIBCPP_HIDE_FROM_ABI friend constexpr bool operator>=(const __ra_iterator& __x, const __ra_iterator& __y) {121 return !(__x < __y);122 }123 124 _LIBCPP_HIDE_FROM_ABI friend constexpr auto operator<=>(const __ra_iterator& __x, const __ra_iterator& __y)125 requires three_way_comparable<_Iterator>126 {127 return __x.__iter_ <=> __y.__iter_;128 }129 130 _LIBCPP_HIDE_FROM_ABI friend constexpr __ra_iterator operator+(const __ra_iterator& __i, difference_type __n) {131 auto __tmp = __i;132 __tmp += __n;133 return __tmp;134 }135 136 _LIBCPP_HIDE_FROM_ABI friend constexpr __ra_iterator operator+(difference_type __n, const __ra_iterator& __i) {137 return __i + __n;138 }139 140 _LIBCPP_HIDE_FROM_ABI friend constexpr __ra_iterator operator-(const __ra_iterator& __i, difference_type __n) {141 auto __tmp = __i;142 __tmp -= __n;143 return __tmp;144 }145 146 _LIBCPP_HIDE_FROM_ABI friend constexpr difference_type operator-(const __ra_iterator& __x, const __ra_iterator& __y) {147 return __x.__iter_ - __y.__iter_;148 }149};150 151_LIBCPP_END_NAMESPACE_STD152 153#endif // _LIBCPP_STD_VER >= 23154 155_LIBCPP_POP_MACROS156 157#endif // _LIBCPP___FLAT_SET_RA_ITERATOR_H158