diff options
Diffstat (limited to 'libcxx/include/__iterator/reverse_iterator.h')
| -rw-r--r-- | libcxx/include/__iterator/reverse_iterator.h | 175 |
1 files changed, 155 insertions, 20 deletions
diff --git a/libcxx/include/__iterator/reverse_iterator.h b/libcxx/include/__iterator/reverse_iterator.h index 449eb529aa98..89bda19effef 100644 --- a/libcxx/include/__iterator/reverse_iterator.h +++ b/libcxx/include/__iterator/reverse_iterator.h @@ -10,16 +10,25 @@ #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/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/prev.h> +#include <__iterator/readable_traits.h> #include <__memory/addressof.h> +#include <__utility/move.h> #include <type_traits> #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) -#pragma GCC system_header +# pragma GCC system_header #endif _LIBCPP_BEGIN_NAMESPACE_STD @@ -41,22 +50,31 @@ private: _Iter __t; // no longer used as of LWG #2360, not removed due to ABI break #endif +#if _LIBCPP_STD_VER > 17 + static_assert(__is_cpp17_bidirectional_iterator<_Iter>::value || bidirectional_iterator<_Iter>, + "reverse_iterator<It> requires It to be a bidirectional iterator."); +#endif // _LIBCPP_STD_VER > 17 + protected: _Iter current; public: - typedef _Iter iterator_type; - typedef typename iterator_traits<_Iter>::difference_type difference_type; - typedef typename iterator_traits<_Iter>::reference reference; - typedef typename iterator_traits<_Iter>::pointer pointer; - typedef _If<__is_cpp17_random_access_iterator<_Iter>::value, - random_access_iterator_tag, - typename iterator_traits<_Iter>::iterator_category> iterator_category; - typedef typename iterator_traits<_Iter>::value_type value_type; + using iterator_type = _Iter; + using iterator_category = _If<__is_cpp17_random_access_iterator<_Iter>::value, + random_access_iterator_tag, + typename iterator_traits<_Iter>::iterator_category>; + using pointer = typename iterator_traits<_Iter>::pointer; #if _LIBCPP_STD_VER > 17 - typedef _If<__is_cpp17_random_access_iterator<_Iter>::value, - random_access_iterator_tag, - bidirectional_iterator_tag> iterator_concept; + using iterator_concept = _If<__is_cpp17_random_access_iterator<_Iter>::value, + 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 @@ -114,32 +132,75 @@ public: _Iter base() const {return current;} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reference operator*() const {_Iter __tmp = current; return *--__tmp;} + +#if _LIBCPP_STD_VER > 17 + _LIBCPP_INLINE_VISIBILITY + 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_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 - pointer operator->() const {return _VSTD::addressof(operator*());} + pointer operator->() const { + return std::addressof(operator*()); + } +#endif // _LIBCPP_STD_VER > 17 + _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reverse_iterator& operator++() {--current; return *this;} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 - reverse_iterator operator++(int) {reverse_iterator __tmp(*this); --current; return __tmp;} + reverse_iterator operator++(int) {reverse_iterator __tmp(*this); --current; return __tmp;} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reverse_iterator& operator--() {++current; return *this;} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 - reverse_iterator operator--(int) {reverse_iterator __tmp(*this); ++current; return __tmp;} + reverse_iterator operator--(int) {reverse_iterator __tmp(*this); ++current; return __tmp;} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 - reverse_iterator operator+ (difference_type __n) const {return reverse_iterator(current - __n);} + reverse_iterator operator+(difference_type __n) const {return reverse_iterator(current - __n);} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reverse_iterator& operator+=(difference_type __n) {current -= __n; return *this;} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 - reverse_iterator operator- (difference_type __n) const {return reverse_iterator(current + __n);} + reverse_iterator operator-(difference_type __n) const {return reverse_iterator(current + __n);} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 reverse_iterator& operator-=(difference_type __n) {current += __n; return *this;} _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 - reference operator[](difference_type __n) const {return *(*this + __n);} + reference operator[](difference_type __n) const {return *(*this + __n);} + +#if _LIBCPP_STD_VER > 17 + _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(--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(--declval<_Iter&>(), --declval<_Iter2&>()))) { + auto __xtmp = __x.base(); + auto __ytmp = __y.base(); + ranges::iter_swap(--__xtmp, --__ytmp); + } +#endif // _LIBCPP_STD_VER > 17 }; template <class _Iter1, class _Iter2> inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 bool operator==(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y) +#if _LIBCPP_STD_VER > 17 + requires requires { + { __x.base() == __y.base() } -> convertible_to<bool>; + } +#endif // _LIBCPP_STD_VER > 17 { return __x.base() == __y.base(); } @@ -148,6 +209,11 @@ template <class _Iter1, class _Iter2> inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 bool operator<(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y) +#if _LIBCPP_STD_VER > 17 + requires requires { + { __x.base() > __y.base() } -> convertible_to<bool>; + } +#endif // _LIBCPP_STD_VER > 17 { return __x.base() > __y.base(); } @@ -156,6 +222,11 @@ template <class _Iter1, class _Iter2> inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 bool operator!=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y) +#if _LIBCPP_STD_VER > 17 + requires requires { + { __x.base() != __y.base() } -> convertible_to<bool>; + } +#endif // _LIBCPP_STD_VER > 17 { return __x.base() != __y.base(); } @@ -164,6 +235,11 @@ template <class _Iter1, class _Iter2> inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 bool operator>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y) +#if _LIBCPP_STD_VER > 17 + requires requires { + { __x.base() < __y.base() } -> convertible_to<bool>; + } +#endif // _LIBCPP_STD_VER > 17 { return __x.base() < __y.base(); } @@ -172,6 +248,11 @@ template <class _Iter1, class _Iter2> inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 bool operator>=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y) +#if _LIBCPP_STD_VER > 17 + requires requires { + { __x.base() <= __y.base() } -> convertible_to<bool>; + } +#endif // _LIBCPP_STD_VER > 17 { return __x.base() <= __y.base(); } @@ -180,11 +261,16 @@ template <class _Iter1, class _Iter2> inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 bool operator<=(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& __y) +#if _LIBCPP_STD_VER > 17 + requires requires { + { __x.base() >= __y.base() } -> convertible_to<bool>; + } +#endif // _LIBCPP_STD_VER > 17 { return __x.base() >= __y.base(); } -#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_CONCEPTS) +#if _LIBCPP_STD_VER > 17 template <class _Iter1, three_way_comparable_with<_Iter1> _Iter2> _LIBCPP_HIDE_FROM_ABI constexpr compare_three_way_result_t<_Iter1, _Iter2> @@ -192,7 +278,7 @@ operator<=>(const reverse_iterator<_Iter1>& __x, const reverse_iterator<_Iter2>& { return __y.base() <=> __x.base(); } -#endif +#endif // _LIBCPP_STD_VER > 17 #ifndef _LIBCPP_CXX03_LANG template <class _Iter1, class _Iter2> @@ -221,6 +307,12 @@ operator+(typename reverse_iterator<_Iter>::difference_type __n, const reverse_i return reverse_iterator<_Iter>(__x.base() - __n); } +#if _LIBCPP_STD_VER > 17 +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 > 17 + #if _LIBCPP_STD_VER > 11 template <class _Iter> inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14 @@ -230,6 +322,49 @@ reverse_iterator<_Iter> make_reverse_iterator(_Iter __i) } #endif +template <class _Iter> +using _ReverseWrapper = reverse_iterator<reverse_iterator<_Iter> >; + +template <class _Iter, bool __b> +struct __unwrap_iter_impl<_ReverseWrapper<_Iter>, __b> { + static _LIBCPP_CONSTEXPR decltype(std::__unwrap_iter(std::declval<_Iter>())) + __apply(_ReverseWrapper<_Iter> __i) _NOEXCEPT { + return std::__unwrap_iter(__i.base().base()); + } +}; + +template <class _OrigIter, class _UnwrappedIter> +struct __rewrap_iter_impl<_ReverseWrapper<_OrigIter>, _UnwrappedIter> { + template <class _Iter> + struct _ReverseWrapperCount { + static _LIBCPP_CONSTEXPR const size_t value = 1; + }; + + template <class _Iter> + struct _ReverseWrapperCount<_ReverseWrapper<_Iter> > { + static _LIBCPP_CONSTEXPR const size_t value = 1 + _ReverseWrapperCount<_Iter>::value; + }; + + template <size_t _RewrapCount, class _OIter, class _UIter, __enable_if_t<_RewrapCount != 0, int> = 0> + _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR _ReverseWrapper<_OIter> __rewrap(_ReverseWrapper<_OIter> __iter1, + _UIter __iter2) { + return _ReverseWrapper<_OIter>( + reverse_iterator<_OIter>(__rewrap<_RewrapCount - 1>(__iter1.base().base(), __iter2))); + } + + template <size_t _RewrapCount, class _OIter, class _UIter, __enable_if_t<_RewrapCount == 0, int> = 0> + _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR decltype(std::__rewrap_iter(std::declval<_OIter>(), + std::declval<_UIter>())) + __rewrap(_OIter __iter1, _UIter __iter2) { + return std::__rewrap_iter(__iter1, __iter2); + } + + _LIBCPP_HIDE_FROM_ABI static _LIBCPP_CONSTEXPR _ReverseWrapper<_OrigIter> __apply(_ReverseWrapper<_OrigIter> __iter1, + _UnwrappedIter __iter2) { + return __rewrap<_ReverseWrapperCount<_OrigIter>::value>(__iter1, __iter2); + } +}; + _LIBCPP_END_NAMESPACE_STD #endif // _LIBCPP___ITERATOR_REVERSE_ITERATOR_H |