181ad6265SDimitry Andric // -*- C++ -*- 281ad6265SDimitry Andric //===----------------------------------------------------------------------===// 381ad6265SDimitry Andric // 481ad6265SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 581ad6265SDimitry Andric // See https://llvm.org/LICENSE.txt for license information. 681ad6265SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 781ad6265SDimitry Andric // 881ad6265SDimitry Andric //===----------------------------------------------------------------------===// 9bdd1243dSDimitry Andric 1081ad6265SDimitry Andric #ifndef _LIBCPP___RANGES_REND_H 1181ad6265SDimitry Andric #define _LIBCPP___RANGES_REND_H 1281ad6265SDimitry Andric 1381ad6265SDimitry Andric #include <__concepts/class_or_enum.h> 1481ad6265SDimitry Andric #include <__concepts/same_as.h> 1581ad6265SDimitry Andric #include <__config> 1681ad6265SDimitry Andric #include <__iterator/concepts.h> 1781ad6265SDimitry Andric #include <__iterator/readable_traits.h> 1881ad6265SDimitry Andric #include <__iterator/reverse_iterator.h> 1981ad6265SDimitry Andric #include <__ranges/access.h> 2081ad6265SDimitry Andric #include <__ranges/rbegin.h> 2106c3fb27SDimitry Andric #include <__type_traits/decay.h> 2206c3fb27SDimitry Andric #include <__type_traits/is_reference.h> 2306c3fb27SDimitry Andric #include <__type_traits/remove_cvref.h> 2406c3fb27SDimitry Andric #include <__type_traits/remove_reference.h> 2581ad6265SDimitry Andric #include <__utility/auto_cast.h> 2681ad6265SDimitry Andric 2781ad6265SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 2881ad6265SDimitry Andric # pragma GCC system_header 2981ad6265SDimitry Andric #endif 3081ad6265SDimitry Andric 3181ad6265SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD 3281ad6265SDimitry Andric 3306c3fb27SDimitry Andric #if _LIBCPP_STD_VER >= 20 3481ad6265SDimitry Andric 3581ad6265SDimitry Andric // [range.access.rend] 3681ad6265SDimitry Andric 3781ad6265SDimitry Andric namespace ranges { 3881ad6265SDimitry Andric namespace __rend { 3981ad6265SDimitry Andric template <class _Tp> 40*0fca6ea1SDimitry Andric concept __member_rend = __can_borrow<_Tp> && requires(_Tp&& __t) { 4181ad6265SDimitry Andric ranges::rbegin(__t); 4281ad6265SDimitry Andric { _LIBCPP_AUTO_CAST(__t.rend()) } -> sentinel_for<decltype(ranges::rbegin(__t))>; 4381ad6265SDimitry Andric }; 4481ad6265SDimitry Andric 45*0fca6ea1SDimitry Andric void rend() = delete; 4681ad6265SDimitry Andric 4781ad6265SDimitry Andric template <class _Tp> 4881ad6265SDimitry Andric concept __unqualified_rend = 49cb14a3feSDimitry Andric !__member_rend<_Tp> && __can_borrow<_Tp> && __class_or_enum<remove_cvref_t<_Tp>> && requires(_Tp&& __t) { 5081ad6265SDimitry Andric ranges::rbegin(__t); 5181ad6265SDimitry Andric { _LIBCPP_AUTO_CAST(rend(__t)) } -> sentinel_for<decltype(ranges::rbegin(__t))>; 5281ad6265SDimitry Andric }; 5381ad6265SDimitry Andric 5481ad6265SDimitry Andric template <class _Tp> 55cb14a3feSDimitry Andric concept __can_reverse = __can_borrow<_Tp> && !__member_rend<_Tp> && !__unqualified_rend<_Tp> && requires(_Tp&& __t) { 5681ad6265SDimitry Andric { ranges::begin(__t) } -> same_as<decltype(ranges::end(__t))>; 5781ad6265SDimitry Andric { ranges::begin(__t) } -> bidirectional_iterator; 5881ad6265SDimitry Andric }; 5981ad6265SDimitry Andric 6081ad6265SDimitry Andric class __fn { 6181ad6265SDimitry Andric public: 6281ad6265SDimitry Andric template <class _Tp> 6381ad6265SDimitry Andric requires __member_rend<_Tp> 6481ad6265SDimitry Andric [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const 65cb14a3feSDimitry Andric noexcept(noexcept(_LIBCPP_AUTO_CAST(__t.rend()))) { 6681ad6265SDimitry Andric return _LIBCPP_AUTO_CAST(__t.rend()); 6781ad6265SDimitry Andric } 6881ad6265SDimitry Andric 6981ad6265SDimitry Andric template <class _Tp> 7081ad6265SDimitry Andric requires __unqualified_rend<_Tp> 7181ad6265SDimitry Andric [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const 72cb14a3feSDimitry Andric noexcept(noexcept(_LIBCPP_AUTO_CAST(rend(__t)))) { 7381ad6265SDimitry Andric return _LIBCPP_AUTO_CAST(rend(__t)); 7481ad6265SDimitry Andric } 7581ad6265SDimitry Andric 7681ad6265SDimitry Andric template <class _Tp> 7781ad6265SDimitry Andric requires __can_reverse<_Tp> 7881ad6265SDimitry Andric [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const 79cb14a3feSDimitry Andric noexcept(noexcept(ranges::begin(__t))) { 8081ad6265SDimitry Andric return std::make_reverse_iterator(ranges::begin(__t)); 8181ad6265SDimitry Andric } 8281ad6265SDimitry Andric 8381ad6265SDimitry Andric void operator()(auto&&) const = delete; 8481ad6265SDimitry Andric }; 8581ad6265SDimitry Andric } // namespace __rend 8681ad6265SDimitry Andric 8781ad6265SDimitry Andric inline namespace __cpo { 8881ad6265SDimitry Andric inline constexpr auto rend = __rend::__fn{}; 8981ad6265SDimitry Andric } // namespace __cpo 9081ad6265SDimitry Andric } // namespace ranges 9181ad6265SDimitry Andric 9281ad6265SDimitry Andric // [range.access.crend] 9381ad6265SDimitry Andric 9481ad6265SDimitry Andric namespace ranges { 9581ad6265SDimitry Andric namespace __crend { 9681ad6265SDimitry Andric struct __fn { 9781ad6265SDimitry Andric template <class _Tp> 9881ad6265SDimitry Andric requires is_lvalue_reference_v<_Tp&&> 99cb14a3feSDimitry Andric [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const 10081ad6265SDimitry Andric noexcept(noexcept(ranges::rend(static_cast<const remove_reference_t<_Tp>&>(__t)))) 101cb14a3feSDimitry Andric -> decltype(ranges::rend(static_cast<const remove_reference_t<_Tp>&>(__t))) { 102cb14a3feSDimitry Andric return ranges::rend(static_cast<const remove_reference_t<_Tp>&>(__t)); 103cb14a3feSDimitry Andric } 10481ad6265SDimitry Andric 10581ad6265SDimitry Andric template <class _Tp> 10681ad6265SDimitry Andric requires is_rvalue_reference_v<_Tp&&> 107*0fca6ea1SDimitry Andric [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const noexcept( 108*0fca6ea1SDimitry Andric noexcept(ranges::rend(static_cast<const _Tp&&>(__t)))) -> decltype(ranges::rend(static_cast<const _Tp&&>(__t))) { 109cb14a3feSDimitry Andric return ranges::rend(static_cast<const _Tp&&>(__t)); 110cb14a3feSDimitry Andric } 11181ad6265SDimitry Andric }; 11281ad6265SDimitry Andric } // namespace __crend 11381ad6265SDimitry Andric 11481ad6265SDimitry Andric inline namespace __cpo { 11581ad6265SDimitry Andric inline constexpr auto crend = __crend::__fn{}; 11681ad6265SDimitry Andric } // namespace __cpo 11781ad6265SDimitry Andric } // namespace ranges 11881ad6265SDimitry Andric 11906c3fb27SDimitry Andric #endif // _LIBCPP_STD_VER >= 20 12081ad6265SDimitry Andric 12181ad6265SDimitry Andric _LIBCPP_END_NAMESPACE_STD 12281ad6265SDimitry Andric 12381ad6265SDimitry Andric #endif // _LIBCPP___RANGES_REND_H 124