80643d9366
We plan to add concepts for checking that iterators actually provide what they claim to. This is to avoid people thinking that these type traits actually check the iterator requirements in more detail. Reviewed By: ldionne, #libc Spies: Mordante, libcxx-commits, wenlei Differential Revision: https://reviews.llvm.org/D150801
534 lines
20 KiB
C++
534 lines
20 KiB
C++
// -*- C++ -*-
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//===----------------------------------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#ifndef _LIBCPP___ITERATOR_REVERSE_ITERATOR_H
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#define _LIBCPP___ITERATOR_REVERSE_ITERATOR_H
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#include <__algorithm/unwrap_iter.h>
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#include <__compare/compare_three_way_result.h>
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#include <__compare/three_way_comparable.h>
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#include <__concepts/convertible_to.h>
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#include <__config>
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#include <__iterator/advance.h>
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#include <__iterator/concepts.h>
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#include <__iterator/incrementable_traits.h>
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#include <__iterator/iter_move.h>
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#include <__iterator/iter_swap.h>
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#include <__iterator/iterator.h>
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#include <__iterator/iterator_traits.h>
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#include <__iterator/next.h>
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#include <__iterator/prev.h>
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#include <__iterator/readable_traits.h>
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#include <__iterator/segmented_iterator.h>
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#include <__memory/addressof.h>
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#include <__ranges/access.h>
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#include <__ranges/concepts.h>
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#include <__ranges/subrange.h>
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#include <__type_traits/conditional.h>
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#include <__type_traits/enable_if.h>
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#include <__type_traits/is_assignable.h>
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#include <__type_traits/is_convertible.h>
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#include <__type_traits/is_nothrow_copy_constructible.h>
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#include <__type_traits/is_pointer.h>
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#include <__type_traits/is_same.h>
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#include <__utility/declval.h>
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#include <__utility/move.h>
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#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
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# pragma GCC system_header
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#endif
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_LIBCPP_BEGIN_NAMESPACE_STD
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_LIBCPP_SUPPRESS_DEPRECATED_PUSH
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template <class _Iter>
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class _LIBCPP_TEMPLATE_VIS reverse_iterator
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#if _LIBCPP_STD_VER <= 14 || !defined(_LIBCPP_ABI_NO_ITERATOR_BASES)
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: public iterator<typename iterator_traits<_Iter>::iterator_category,
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typename iterator_traits<_Iter>::value_type,
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typename iterator_traits<_Iter>::difference_type,
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typename iterator_traits<_Iter>::pointer,
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typename iterator_traits<_Iter>::reference>
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#endif
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{
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_LIBCPP_SUPPRESS_DEPRECATED_POP
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private:
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#ifndef _LIBCPP_ABI_NO_ITERATOR_BASES
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_Iter __t_; // no longer used as of LWG #2360, not removed due to ABI break
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#endif
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#if _LIBCPP_STD_VER >= 20
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static_assert(__has_bidirectional_iterator_category<_Iter>::value || bidirectional_iterator<_Iter>,
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"reverse_iterator<It> requires It to be a bidirectional iterator.");
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#endif // _LIBCPP_STD_VER >= 20
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protected:
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_Iter current;
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public:
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using iterator_type = _Iter;
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using iterator_category = _If<__has_random_access_iterator_category<_Iter>::value,
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random_access_iterator_tag,
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typename iterator_traits<_Iter>::iterator_category>;
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using pointer = typename iterator_traits<_Iter>::pointer;
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#if _LIBCPP_STD_VER >= 20
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using iterator_concept = _If<random_access_iterator<_Iter>, random_access_iterator_tag, bidirectional_iterator_tag>;
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using value_type = iter_value_t<_Iter>;
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using difference_type = iter_difference_t<_Iter>;
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using reference = iter_reference_t<_Iter>;
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#else
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using value_type = typename iterator_traits<_Iter>::value_type;
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using difference_type = typename iterator_traits<_Iter>::difference_type;
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using reference = typename iterator_traits<_Iter>::reference;
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#endif
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#ifndef _LIBCPP_ABI_NO_ITERATOR_BASES
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator() : __t_(), current() {}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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explicit reverse_iterator(_Iter __x) : __t_(__x), current(__x) {}
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template <class _Up, class = __enable_if_t<
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!is_same<_Up, _Iter>::value && is_convertible<_Up const&, _Iter>::value
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> >
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator(const reverse_iterator<_Up>& __u)
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: __t_(__u.base()), current(__u.base())
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{ }
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template <class _Up, class = __enable_if_t<
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!is_same<_Up, _Iter>::value &&
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is_convertible<_Up const&, _Iter>::value &&
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is_assignable<_Iter&, _Up const&>::value
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> >
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator& operator=(const reverse_iterator<_Up>& __u) {
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__t_ = current = __u.base();
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return *this;
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}
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#else
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator() : current() {}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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explicit reverse_iterator(_Iter __x) : current(__x) {}
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template <class _Up, class = __enable_if_t<
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!is_same<_Up, _Iter>::value && is_convertible<_Up const&, _Iter>::value
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> >
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator(const reverse_iterator<_Up>& __u)
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: current(__u.base())
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{ }
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template <class _Up, class = __enable_if_t<
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!is_same<_Up, _Iter>::value &&
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is_convertible<_Up const&, _Iter>::value &&
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is_assignable<_Iter&, _Up const&>::value
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> >
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator& operator=(const reverse_iterator<_Up>& __u) {
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current = __u.base();
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return *this;
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}
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#endif
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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_Iter base() const {return current;}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reference operator*() const {_Iter __tmp = current; return *--__tmp;}
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#if _LIBCPP_STD_VER >= 20
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_LIBCPP_INLINE_VISIBILITY
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constexpr pointer operator->() const
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requires is_pointer_v<_Iter> || requires(const _Iter __i) { __i.operator->(); }
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{
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if constexpr (is_pointer_v<_Iter>) {
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return std::prev(current);
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} else {
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return std::prev(current).operator->();
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}
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}
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#else
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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pointer operator->() const {
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return std::addressof(operator*());
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}
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#endif // _LIBCPP_STD_VER >= 20
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator& operator++() {--current; return *this;}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator operator++(int) {reverse_iterator __tmp(*this); --current; return __tmp;}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator& operator--() {++current; return *this;}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator operator--(int) {reverse_iterator __tmp(*this); ++current; return __tmp;}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator operator+(difference_type __n) const {return reverse_iterator(current - __n);}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator& operator+=(difference_type __n) {current -= __n; return *this;}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator operator-(difference_type __n) const {return reverse_iterator(current + __n);}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator& operator-=(difference_type __n) {current += __n; return *this;}
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_LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reference operator[](difference_type __n) const {return *(*this + __n);}
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#if _LIBCPP_STD_VER >= 20
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_LIBCPP_HIDE_FROM_ABI friend constexpr
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iter_rvalue_reference_t<_Iter> iter_move(const reverse_iterator& __i)
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noexcept(is_nothrow_copy_constructible_v<_Iter> &&
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noexcept(ranges::iter_move(--std::declval<_Iter&>()))) {
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auto __tmp = __i.base();
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return ranges::iter_move(--__tmp);
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}
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template <indirectly_swappable<_Iter> _Iter2>
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_LIBCPP_HIDE_FROM_ABI friend constexpr
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void iter_swap(const reverse_iterator& __x, const reverse_iterator<_Iter2>& __y)
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noexcept(is_nothrow_copy_constructible_v<_Iter> &&
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is_nothrow_copy_constructible_v<_Iter2> &&
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noexcept(ranges::iter_swap(--std::declval<_Iter&>(), --std::declval<_Iter2&>()))) {
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auto __xtmp = __x.base();
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auto __ytmp = __y.base();
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ranges::iter_swap(--__xtmp, --__ytmp);
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}
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#endif // _LIBCPP_STD_VER >= 20
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};
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template <class _Iter1, class _Iter2>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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bool
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operator==(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
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#if _LIBCPP_STD_VER >= 20
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requires requires {
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{ __x.base() == __y.base() } -> convertible_to<bool>;
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}
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#endif // _LIBCPP_STD_VER >= 20
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{
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return __x.base() == __y.base();
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}
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template <class _Iter1, class _Iter2>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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bool
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operator<(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
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#if _LIBCPP_STD_VER >= 20
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requires requires {
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{ __x.base() > __y.base() } -> convertible_to<bool>;
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}
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#endif // _LIBCPP_STD_VER >= 20
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{
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return __x.base() > __y.base();
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}
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template <class _Iter1, class _Iter2>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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bool
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operator!=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
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#if _LIBCPP_STD_VER >= 20
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requires requires {
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{ __x.base() != __y.base() } -> convertible_to<bool>;
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}
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#endif // _LIBCPP_STD_VER >= 20
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{
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return __x.base() != __y.base();
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}
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template <class _Iter1, class _Iter2>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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bool
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operator>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
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#if _LIBCPP_STD_VER >= 20
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requires requires {
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{ __x.base() < __y.base() } -> convertible_to<bool>;
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}
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#endif // _LIBCPP_STD_VER >= 20
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{
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return __x.base() < __y.base();
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}
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template <class _Iter1, class _Iter2>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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bool
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operator>=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
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#if _LIBCPP_STD_VER >= 20
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requires requires {
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{ __x.base() <= __y.base() } -> convertible_to<bool>;
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}
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#endif // _LIBCPP_STD_VER >= 20
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{
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return __x.base() <= __y.base();
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}
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template <class _Iter1, class _Iter2>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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bool
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operator<=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
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#if _LIBCPP_STD_VER >= 20
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requires requires {
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{ __x.base() >= __y.base() } -> convertible_to<bool>;
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}
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#endif // _LIBCPP_STD_VER >= 20
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{
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return __x.base() >= __y.base();
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}
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#if _LIBCPP_STD_VER >= 20
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template <class _Iter1, three_way_comparable_with<_Iter1> _Iter2>
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_LIBCPP_HIDE_FROM_ABI constexpr
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compare_three_way_result_t<_Iter1, _Iter2>
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operator<=>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
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{
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return __y.base() <=> __x.base();
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}
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#endif // _LIBCPP_STD_VER >= 20
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#ifndef _LIBCPP_CXX03_LANG
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template <class _Iter1, class _Iter2>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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auto
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operator-(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
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-> decltype(__y.base() - __x.base())
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{
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return __y.base() - __x.base();
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}
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#else
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template <class _Iter1, class _Iter2>
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inline _LIBCPP_INLINE_VISIBILITY
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typename reverse_iterator<_Iter1>::difference_type
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operator-(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y)
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{
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return __y.base() - __x.base();
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}
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#endif
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template <class _Iter>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator<_Iter>
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operator+(typename reverse_iterator<_Iter>::difference_type __n, const reverse_iterator<_Iter>& __x)
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{
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return reverse_iterator<_Iter>(__x.base() - __n);
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}
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#if _LIBCPP_STD_VER >= 20
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template <class _Iter1, class _Iter2>
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requires (!sized_sentinel_for<_Iter1, _Iter2>)
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inline constexpr bool disable_sized_sentinel_for<reverse_iterator<_Iter1>, reverse_iterator<_Iter2>> = true;
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#endif // _LIBCPP_STD_VER >= 20
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#if _LIBCPP_STD_VER >= 14
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template <class _Iter>
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inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_SINCE_CXX17
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reverse_iterator<_Iter> make_reverse_iterator(_Iter __i)
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{
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return reverse_iterator<_Iter>(__i);
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}
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#endif
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#if _LIBCPP_STD_VER <= 17
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template <class _Iter>
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using __unconstrained_reverse_iterator = reverse_iterator<_Iter>;
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#else
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// __unconstrained_reverse_iterator allows us to use reverse iterators in the implementation of algorithms by working
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// around a language issue in C++20.
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// In C++20, when a reverse iterator wraps certain C++20-hostile iterators, calling comparison operators on it will
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// result in a compilation error. However, calling comparison operators on the pristine hostile iterator is not
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// an error. Thus, we cannot use reverse_iterators in the implementation of an algorithm that accepts a
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// C++20-hostile iterator. This class is an internal workaround -- it is a copy of reverse_iterator with
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// tweaks to make it support hostile iterators.
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//
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// A C++20-hostile iterator is one that defines a comparison operator where one of the arguments is an exact match
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// and the other requires an implicit conversion, for example:
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// friend bool operator==(const BaseIter&, const DerivedIter&);
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//
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// C++20 rules for rewriting equality operators create another overload of this function with parameters reversed:
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// friend bool operator==(const DerivedIter&, const BaseIter&);
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//
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// This creates an ambiguity in overload resolution.
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//
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// Clang treats this ambiguity differently in different contexts. When operator== is actually called in the function
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// body, the code is accepted with a warning. When a concept requires operator== to be a valid expression, however,
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// it evaluates to false. Thus, the implementation of reverse_iterator::operator== can actually call operator== on its
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// base iterators, but the constraints on reverse_iterator::operator== prevent it from being considered during overload
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// resolution. This class simply removes the problematic constraints from comparison functions.
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template <class _Iter>
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class __unconstrained_reverse_iterator {
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_Iter __iter_;
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public:
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static_assert(__has_bidirectional_iterator_category<_Iter>::value || bidirectional_iterator<_Iter>);
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using iterator_type = _Iter;
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using iterator_category =
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_If<__has_random_access_iterator_category<_Iter>::value, random_access_iterator_tag, __iterator_category_type<_Iter>>;
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using pointer = __iterator_pointer_type<_Iter>;
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using value_type = iter_value_t<_Iter>;
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using difference_type = iter_difference_t<_Iter>;
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using reference = iter_reference_t<_Iter>;
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_LIBCPP_HIDE_FROM_ABI constexpr __unconstrained_reverse_iterator() = default;
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_LIBCPP_HIDE_FROM_ABI constexpr __unconstrained_reverse_iterator(const __unconstrained_reverse_iterator&) = default;
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_LIBCPP_HIDE_FROM_ABI constexpr explicit __unconstrained_reverse_iterator(_Iter __iter) : __iter_(__iter) {}
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_LIBCPP_HIDE_FROM_ABI constexpr _Iter base() const { return __iter_; }
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_LIBCPP_HIDE_FROM_ABI constexpr reference operator*() const {
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auto __tmp = __iter_;
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return *--__tmp;
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}
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_LIBCPP_HIDE_FROM_ABI constexpr pointer operator->() const {
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if constexpr (is_pointer_v<_Iter>) {
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return std::prev(__iter_);
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} else {
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return std::prev(__iter_).operator->();
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}
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}
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_LIBCPP_HIDE_FROM_ABI friend constexpr
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iter_rvalue_reference_t<_Iter> iter_move(const __unconstrained_reverse_iterator& __i)
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noexcept(is_nothrow_copy_constructible_v<_Iter> &&
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noexcept(ranges::iter_move(--std::declval<_Iter&>()))) {
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auto __tmp = __i.base();
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return ranges::iter_move(--__tmp);
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}
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_LIBCPP_HIDE_FROM_ABI constexpr __unconstrained_reverse_iterator& operator++() {
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--__iter_;
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return *this;
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}
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_LIBCPP_HIDE_FROM_ABI constexpr __unconstrained_reverse_iterator operator++(int) {
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auto __tmp = *this;
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--__iter_;
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return __tmp;
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}
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_LIBCPP_HIDE_FROM_ABI constexpr __unconstrained_reverse_iterator& operator--() {
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++__iter_;
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return *this;
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}
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_LIBCPP_HIDE_FROM_ABI constexpr __unconstrained_reverse_iterator operator--(int) {
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auto __tmp = *this;
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++__iter_;
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return __tmp;
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}
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_LIBCPP_HIDE_FROM_ABI constexpr __unconstrained_reverse_iterator& operator+=(difference_type __n) {
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__iter_ -= __n;
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return *this;
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}
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_LIBCPP_HIDE_FROM_ABI constexpr __unconstrained_reverse_iterator& operator-=(difference_type __n) {
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__iter_ += __n;
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return *this;
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}
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_LIBCPP_HIDE_FROM_ABI constexpr __unconstrained_reverse_iterator operator+(difference_type __n) const {
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return __unconstrained_reverse_iterator(__iter_ - __n);
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}
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_LIBCPP_HIDE_FROM_ABI constexpr __unconstrained_reverse_iterator operator-(difference_type __n) const {
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return __unconstrained_reverse_iterator(__iter_ + __n);
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}
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_LIBCPP_HIDE_FROM_ABI constexpr difference_type operator-(const __unconstrained_reverse_iterator& __other) const {
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return __other.__iter_ - __iter_;
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}
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_LIBCPP_HIDE_FROM_ABI constexpr auto operator[](difference_type __n) const { return *(*this + __n); }
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// Deliberately unconstrained unlike the comparison functions in `reverse_iterator` -- see the class comment for the
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// rationale.
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_LIBCPP_HIDE_FROM_ABI friend constexpr bool
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operator==(const __unconstrained_reverse_iterator& __lhs, const __unconstrained_reverse_iterator& __rhs) {
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return __lhs.base() == __rhs.base();
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}
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_LIBCPP_HIDE_FROM_ABI friend constexpr bool
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operator!=(const __unconstrained_reverse_iterator& __lhs, const __unconstrained_reverse_iterator& __rhs) {
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return __lhs.base() != __rhs.base();
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}
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_LIBCPP_HIDE_FROM_ABI friend constexpr bool
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operator<(const __unconstrained_reverse_iterator& __lhs, const __unconstrained_reverse_iterator& __rhs) {
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return __lhs.base() > __rhs.base();
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}
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_LIBCPP_HIDE_FROM_ABI friend constexpr bool
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operator>(const __unconstrained_reverse_iterator& __lhs, const __unconstrained_reverse_iterator& __rhs) {
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return __lhs.base() < __rhs.base();
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}
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_LIBCPP_HIDE_FROM_ABI friend constexpr bool
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operator<=(const __unconstrained_reverse_iterator& __lhs, const __unconstrained_reverse_iterator& __rhs) {
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return __lhs.base() >= __rhs.base();
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}
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_LIBCPP_HIDE_FROM_ABI friend constexpr bool
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operator>=(const __unconstrained_reverse_iterator& __lhs, const __unconstrained_reverse_iterator& __rhs) {
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return __lhs.base() <= __rhs.base();
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}
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};
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#endif // _LIBCPP_STD_VER <= 17
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template <template <class> class _RevIter1, template <class> class _RevIter2, class _Iter>
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|
struct __unwrap_reverse_iter_impl {
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|
using _UnwrappedIter = decltype(__unwrap_iter_impl<_Iter>::__unwrap(std::declval<_Iter>()));
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using _ReverseWrapper = _RevIter1<_RevIter2<_Iter> >;
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static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _ReverseWrapper
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|
__rewrap(_ReverseWrapper __orig_iter, _UnwrappedIter __unwrapped_iter) {
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|
return _ReverseWrapper(
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|
_RevIter2<_Iter>(__unwrap_iter_impl<_Iter>::__rewrap(__orig_iter.base().base(), __unwrapped_iter)));
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|
}
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|
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|
static _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR _UnwrappedIter __unwrap(_ReverseWrapper __i) _NOEXCEPT {
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|
return __unwrap_iter_impl<_Iter>::__unwrap(__i.base().base());
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|
}
|
|
};
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|
|
|
#if _LIBCPP_STD_VER >= 20
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|
template <ranges::bidirectional_range _Range>
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|
_LIBCPP_HIDE_FROM_ABI constexpr ranges::
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|
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>
|
|
: __unwrap_reverse_iter_impl<reverse_iterator, reverse_iterator, _Iter> {};
|
|
|
|
#if _LIBCPP_STD_VER >= 20
|
|
|
|
template <class _Iter, bool __b>
|
|
struct __unwrap_iter_impl<reverse_iterator<__unconstrained_reverse_iterator<_Iter>>, __b>
|
|
: __unwrap_reverse_iter_impl<reverse_iterator, __unconstrained_reverse_iterator, _Iter> {};
|
|
|
|
template <class _Iter, bool __b>
|
|
struct __unwrap_iter_impl<__unconstrained_reverse_iterator<reverse_iterator<_Iter>>, __b>
|
|
: __unwrap_reverse_iter_impl<__unconstrained_reverse_iterator, reverse_iterator, _Iter> {};
|
|
|
|
template <class _Iter, bool __b>
|
|
struct __unwrap_iter_impl<__unconstrained_reverse_iterator<__unconstrained_reverse_iterator<_Iter>>, __b>
|
|
: __unwrap_reverse_iter_impl<__unconstrained_reverse_iterator, __unconstrained_reverse_iterator, _Iter> {};
|
|
|
|
#endif // _LIBCPP_STD_VER >= 20
|
|
|
|
_LIBCPP_END_NAMESPACE_STD
|
|
|
|
#endif // _LIBCPP___ITERATOR_REVERSE_ITERATOR_H
|