// -*- 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
Codebase Browser
llvm