1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346
|
// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___ITERATOR_REVERSE_ITERATOR_H
#define _LIBCPP___ITERATOR_REVERSE_ITERATOR_H
#include <__algorithm/unwrap_iter.h>
#include <__compare/compare_three_way_result.h>
#include <__compare/three_way_comparable.h>
#include <__concepts/convertible_to.h>
#include <__config>
#include <__iterator/advance.h>
#include <__iterator/concepts.h>
#include <__iterator/incrementable_traits.h>
#include <__iterator/iter_move.h>
#include <__iterator/iter_swap.h>
#include <__iterator/iterator.h>
#include <__iterator/iterator_traits.h>
#include <__iterator/next.h>
#include <__iterator/prev.h>
#include <__iterator/readable_traits.h>
#include <__iterator/segmented_iterator.h>
#include <__memory/addressof.h>
#include <__ranges/access.h>
#include <__ranges/concepts.h>
#include <__ranges/subrange.h>
#include <__type_traits/conditional.h>
#include <__type_traits/enable_if.h>
#include <__type_traits/is_assignable.h>
#include <__type_traits/is_convertible.h>
#include <__type_traits/is_nothrow_constructible.h>
#include <__type_traits/is_pointer.h>
#include <__type_traits/is_same.h>
#include <__utility/declval.h>
#include <__utility/move.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
_LIBCPP_SUPPRESS_DEPRECATED_PUSH
template <class _Iter>
class _LIBCPP_TEMPLATE_VIS reverse_iterator
#if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
: public iterator<typename iterator_traits<_Iter>::iterator_category,
typename iterator_traits<_Iter>::value_type,
typename iterator_traits<_Iter>::difference_type,
typename iterator_traits<_Iter>::pointer,
typename iterator_traits<_Iter>::reference>
#endif
{
_LIBCPP_SUPPRESS_DEPRECATED_POP
private:
#ifndef _LIBCPP_ABI_NO_ITERATOR_BASES
_Iter __t_; // no longer used as of LWG #2360, not removed due to ABI break
#endif
#if _LIBCPP_STD_VER >= 20
static_assert(__has_bidirectional_iterator_category<_Iter>::value || bidirectional_iterator<_Iter>,
"reverse_iterator<It> requires It to be a bidirectional iterator.");
#endif // _LIBCPP_STD_VER >= 20
protected:
_Iter current;
public:
using iterator_type = _Iter;
using iterator_category =
_If<__has_random_access_iterator_category<_Iter>::value,
random_access_iterator_tag,
typename iterator_traits<_Iter>::iterator_category>;
using pointer = typename iterator_traits<_Iter>::pointer;
#if _LIBCPP_STD_VER >= 20
using iterator_concept = _If<random_access_iterator<_Iter>, random_access_iterator_tag, bidirectional_iterator_tag>;
using value_type = iter_value_t<_Iter>;
using difference_type = iter_difference_t<_Iter>;
using reference = iter_reference_t<_Iter>;
#else
using value_type = typename iterator_traits<_Iter>::value_type;
using difference_type = typename iterator_traits<_Iter>::difference_type;
using reference = typename iterator_traits<_Iter>::reference;
#endif
#ifndef _LIBCPP_ABI_NO_ITERATOR_BASES
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator() : __t_(), current() {}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 explicit reverse_iterator(_Iter __x) : __t_(__x), current(__x) {}
template <class _Up, __enable_if_t<!is_same<_Up, _Iter>::value && is_convertible<_Up const&, _Iter>::value, int> = 0>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator(const reverse_iterator<_Up>& __u)
: __t_(__u.base()), current(__u.base()) {}
template <class _Up,
__enable_if_t<!is_same<_Up, _Iter>::value && is_convertible<_Up const&, _Iter>::value &&
is_assignable<_Iter&, _Up const&>::value,
int> = 0>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator& operator=(const reverse_iterator<_Up>& __u) {
__t_ = current = __u.base();
return *this;
}
#else
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator() : current() {}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 explicit reverse_iterator(_Iter __x) : current(__x) {}
template <class _Up, __enable_if_t<!is_same<_Up, _Iter>::value && is_convertible<_Up const&, _Iter>::value, int> = 0>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator(const reverse_iterator<_Up>& __u)
: current(__u.base()) {}
template <class _Up,
__enable_if_t<!is_same<_Up, _Iter>::value && is_convertible<_Up const&, _Iter>::value &&
is_assignable<_Iter&, _Up const&>::value,
int> = 0>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator& operator=(const reverse_iterator<_Up>& __u) {
current = __u.base();
return *this;
}
#endif
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 _Iter base() const { return current; }
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator*() const {
_Iter __tmp = current;
return *--__tmp;
}
#if _LIBCPP_STD_VER >= 20
_LIBCPP_HIDE_FROM_ABI constexpr pointer operator->() const
requires is_pointer_v<_Iter> || requires(const _Iter __i) { __i.operator->(); }
{
if constexpr (is_pointer_v<_Iter>) {
return std::prev(current);
} else {
return std::prev(current).operator->();
}
}
#else
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 pointer operator->() const { return std::addressof(operator*()); }
#endif // _LIBCPP_STD_VER >= 20
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator& operator++() {
--current;
return *this;
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator operator++(int) {
reverse_iterator __tmp(*this);
--current;
return __tmp;
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator& operator--() {
++current;
return *this;
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator operator--(int) {
reverse_iterator __tmp(*this);
++current;
return __tmp;
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator operator+(difference_type __n) const {
return reverse_iterator(current - __n);
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator& operator+=(difference_type __n) {
current -= __n;
return *this;
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator operator-(difference_type __n) const {
return reverse_iterator(current + __n);
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator& operator-=(difference_type __n) {
current += __n;
return *this;
}
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reference operator[](difference_type __n) const {
return *(*this + __n);
}
#if _LIBCPP_STD_VER >= 20
_LIBCPP_HIDE_FROM_ABI friend constexpr iter_rvalue_reference_t<_Iter> iter_move(const reverse_iterator& __i) noexcept(
is_nothrow_copy_constructible_v<_Iter> && noexcept(ranges::iter_move(--std::declval<_Iter&>()))) {
auto __tmp = __i.base();
return ranges::iter_move(--__tmp);
}
template <indirectly_swappable<_Iter> _Iter2>
_LIBCPP_HIDE_FROM_ABI friend constexpr void
iter_swap(const reverse_iterator& __x, const reverse_iterator<_Iter2>& __y) noexcept(
is_nothrow_copy_constructible_v<_Iter> && is_nothrow_copy_constructible_v<_Iter2> &&
noexcept(ranges::iter_swap(--std::declval<_Iter&>(), --std::declval<_Iter2&>()))) {
auto __xtmp = __x.base();
auto __ytmp = __y.base();
ranges::iter_swap(--__xtmp, --__ytmp);
}
#endif // _LIBCPP_STD_VER >= 20
};
template <class _Iter1, class _Iter2>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
operator==(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
#if _LIBCPP_STD_VER >= 20
requires requires {
{ __x.base() == __y.base() } -> convertible_to<bool>;
}
#endif // _LIBCPP_STD_VER >= 20
{
return __x.base() == __y.base();
}
template <class _Iter1, class _Iter2>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
operator<(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
#if _LIBCPP_STD_VER >= 20
requires requires {
{ __x.base() > __y.base() } -> convertible_to<bool>;
}
#endif // _LIBCPP_STD_VER >= 20
{
return __x.base() > __y.base();
}
template <class _Iter1, class _Iter2>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
operator!=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
#if _LIBCPP_STD_VER >= 20
requires requires {
{ __x.base() != __y.base() } -> convertible_to<bool>;
}
#endif // _LIBCPP_STD_VER >= 20
{
return __x.base() != __y.base();
}
template <class _Iter1, class _Iter2>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
operator>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
#if _LIBCPP_STD_VER >= 20
requires requires {
{ __x.base() < __y.base() } -> convertible_to<bool>;
}
#endif // _LIBCPP_STD_VER >= 20
{
return __x.base() < __y.base();
}
template <class _Iter1, class _Iter2>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
operator>=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
#if _LIBCPP_STD_VER >= 20
requires requires {
{ __x.base() <= __y.base() } -> convertible_to<bool>;
}
#endif // _LIBCPP_STD_VER >= 20
{
return __x.base() <= __y.base();
}
template <class _Iter1, class _Iter2>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 bool
operator<=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
#if _LIBCPP_STD_VER >= 20
requires requires {
{ __x.base() >= __y.base() } -> convertible_to<bool>;
}
#endif // _LIBCPP_STD_VER >= 20
{
return __x.base() >= __y.base();
}
#if _LIBCPP_STD_VER >= 20
template <class _Iter1, three_way_comparable_with<_Iter1> _Iter2>
_LIBCPP_HIDE_FROM_ABI constexpr compare_three_way_result_t<_Iter1, _Iter2>
operator<=>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y) {
return __y.base() <=> __x.base();
}
#endif // _LIBCPP_STD_VER >= 20
#ifndef _LIBCPP_CXX03_LANG
template <class _Iter1, class _Iter2>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 auto
operator-(const reverse_iterator<_Iter1>& __x,
const reverse_iterator<_Iter2>& __y) -> decltype(__y.base() - __x.base()) {
return __y.base() - __x.base();
}
#else
template <class _Iter1, class _Iter2>
inline _LIBCPP_HIDE_FROM_ABI typename reverse_iterator<_Iter1>::difference_type
operator-(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y) {
return __y.base() - __x.base();
}
#endif
template <class _Iter>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator<_Iter>
operator+(typename reverse_iterator<_Iter>::difference_type __n, const reverse_iterator<_Iter>& __x) {
return reverse_iterator<_Iter>(__x.base() - __n);
}
#if _LIBCPP_STD_VER >= 20
template <class _Iter1, class _Iter2>
requires(!sized_sentinel_for<_Iter1, _Iter2>)
inline constexpr bool disable_sized_sentinel_for<reverse_iterator<_Iter1>, reverse_iterator<_Iter2>> = true;
#endif // _LIBCPP_STD_VER >= 20
#if _LIBCPP_STD_VER >= 14
template <class _Iter>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX17 reverse_iterator<_Iter> make_reverse_iterator(_Iter __i) {
return reverse_iterator<_Iter>(__i);
}
#endif
#if _LIBCPP_STD_VER >= 20
template <ranges::bidirectional_range _Range>
_LIBCPP_HIDE_FROM_ABI constexpr ranges::subrange<reverse_iterator<ranges::iterator_t<_Range>>,
reverse_iterator<ranges::iterator_t<_Range>>>
__reverse_range(_Range&& __range) {
auto __first = ranges::begin(__range);
return {std::make_reverse_iterator(ranges::next(__first, ranges::end(__range))), std::make_reverse_iterator(__first)};
}
#endif
template <class _Iter, bool __b>
struct __unwrap_iter_impl<reverse_iterator<reverse_iterator<_Iter> >, __b> {
using _UnwrappedIter = decltype(__unwrap_iter_impl<_Iter>::__unwrap(std::declval<_Iter>()));
using _ReverseWrapper = reverse_iterator<reverse_iterator<_Iter> >;
static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ReverseWrapper
__rewrap(_ReverseWrapper __orig_iter, _UnwrappedIter __unwrapped_iter) {
return _ReverseWrapper(
reverse_iterator<_Iter>(__unwrap_iter_impl<_Iter>::__rewrap(__orig_iter.base().base(), __unwrapped_iter)));
}
static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _UnwrappedIter __unwrap(_ReverseWrapper __i) _NOEXCEPT {
return __unwrap_iter_impl<_Iter>::__unwrap(__i.base().base());
}
};
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___ITERATOR_REVERSE_ITERATOR_H
|