| // -*- 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___RANGES_ACCESS_H |
| #define _LIBCPP___RANGES_ACCESS_H |
| |
| #include <__concepts/class_or_enum.h> |
| #include <__config> |
| #include <__iterator/concepts.h> |
| #include <__iterator/readable_traits.h> |
| #include <__ranges/enable_borrowed_range.h> |
| #include <__type_traits/decay.h> |
| #include <__type_traits/is_reference.h> |
| #include <__type_traits/remove_cvref.h> |
| #include <__type_traits/remove_reference.h> |
| #include <__utility/auto_cast.h> |
| #include <__utility/declval.h> |
| #include <cstddef> |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| # pragma GCC system_header |
| #endif |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| #if _LIBCPP_STD_VER >= 20 |
| |
| namespace ranges { |
| template <class _Tp> |
| concept __can_borrow = is_lvalue_reference_v<_Tp> || enable_borrowed_range<remove_cvref_t<_Tp>>; |
| } // namespace ranges |
| |
| // [range.access.begin] |
| |
| namespace ranges { |
| namespace __begin { |
| template <class _Tp> |
| concept __member_begin = __can_borrow<_Tp> && requires(_Tp&& __t) { |
| { _LIBCPP_AUTO_CAST(__t.begin()) } -> input_or_output_iterator; |
| }; |
| |
| void begin() = delete; |
| |
| template <class _Tp> |
| concept __unqualified_begin = |
| !__member_begin<_Tp> && __can_borrow<_Tp> && __class_or_enum<remove_cvref_t<_Tp>> && requires(_Tp&& __t) { |
| { _LIBCPP_AUTO_CAST(begin(__t)) } -> input_or_output_iterator; |
| }; |
| |
| struct __fn { |
| template <class _Tp> |
| [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp (&__t)[]) const noexcept |
| requires(sizeof(_Tp) >= 0) // Disallow incomplete element types. |
| { |
| return __t + 0; |
| } |
| |
| template <class _Tp, size_t _Np> |
| [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp (&__t)[_Np]) const noexcept |
| requires(sizeof(_Tp) >= 0) // Disallow incomplete element types. |
| { |
| return __t + 0; |
| } |
| |
| template <class _Tp> |
| requires __member_begin<_Tp> |
| [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const |
| noexcept(noexcept(_LIBCPP_AUTO_CAST(__t.begin()))) { |
| return _LIBCPP_AUTO_CAST(__t.begin()); |
| } |
| |
| template <class _Tp> |
| requires __unqualified_begin<_Tp> |
| [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const |
| noexcept(noexcept(_LIBCPP_AUTO_CAST(begin(__t)))) { |
| return _LIBCPP_AUTO_CAST(begin(__t)); |
| } |
| |
| void operator()(auto&&) const = delete; |
| }; |
| } // namespace __begin |
| |
| inline namespace __cpo { |
| inline constexpr auto begin = __begin::__fn{}; |
| } // namespace __cpo |
| } // namespace ranges |
| |
| // [range.range] |
| |
| namespace ranges { |
| template <class _Tp> |
| using iterator_t = decltype(ranges::begin(std::declval<_Tp&>())); |
| } // namespace ranges |
| |
| // [range.access.end] |
| |
| namespace ranges { |
| namespace __end { |
| template <class _Tp> |
| concept __member_end = __can_borrow<_Tp> && requires(_Tp&& __t) { |
| typename iterator_t<_Tp>; |
| { _LIBCPP_AUTO_CAST(__t.end()) } -> sentinel_for<iterator_t<_Tp>>; |
| }; |
| |
| void end() = delete; |
| |
| template <class _Tp> |
| concept __unqualified_end = |
| !__member_end<_Tp> && __can_borrow<_Tp> && __class_or_enum<remove_cvref_t<_Tp>> && requires(_Tp&& __t) { |
| typename iterator_t<_Tp>; |
| { _LIBCPP_AUTO_CAST(end(__t)) } -> sentinel_for<iterator_t<_Tp>>; |
| }; |
| |
| struct __fn { |
| template <class _Tp, size_t _Np> |
| [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp (&__t)[_Np]) const noexcept |
| requires(sizeof(_Tp) >= 0) // Disallow incomplete element types. |
| { |
| return __t + _Np; |
| } |
| |
| template <class _Tp> |
| requires __member_end<_Tp> |
| [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const |
| noexcept(noexcept(_LIBCPP_AUTO_CAST(__t.end()))) { |
| return _LIBCPP_AUTO_CAST(__t.end()); |
| } |
| |
| template <class _Tp> |
| requires __unqualified_end<_Tp> |
| [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const |
| noexcept(noexcept(_LIBCPP_AUTO_CAST(end(__t)))) { |
| return _LIBCPP_AUTO_CAST(end(__t)); |
| } |
| |
| void operator()(auto&&) const = delete; |
| }; |
| } // namespace __end |
| |
| inline namespace __cpo { |
| inline constexpr auto end = __end::__fn{}; |
| } // namespace __cpo |
| } // namespace ranges |
| |
| // [range.access.cbegin] |
| |
| namespace ranges { |
| namespace __cbegin { |
| struct __fn { |
| template <class _Tp> |
| requires is_lvalue_reference_v<_Tp&&> |
| [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const |
| noexcept(noexcept(ranges::begin(static_cast<const remove_reference_t<_Tp>&>(__t)))) |
| -> decltype(ranges::begin(static_cast<const remove_reference_t<_Tp>&>(__t))) { |
| return ranges::begin(static_cast<const remove_reference_t<_Tp>&>(__t)); |
| } |
| |
| template <class _Tp> |
| requires is_rvalue_reference_v<_Tp&&> |
| [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const |
| noexcept(noexcept(ranges::begin(static_cast<const _Tp&&>(__t)))) |
| -> decltype(ranges::begin(static_cast<const _Tp&&>(__t))) { |
| return ranges::begin(static_cast<const _Tp&&>(__t)); |
| } |
| }; |
| } // namespace __cbegin |
| |
| inline namespace __cpo { |
| inline constexpr auto cbegin = __cbegin::__fn{}; |
| } // namespace __cpo |
| } // namespace ranges |
| |
| // [range.access.cend] |
| |
| namespace ranges { |
| namespace __cend { |
| struct __fn { |
| template <class _Tp> |
| requires is_lvalue_reference_v<_Tp&&> |
| [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const |
| noexcept(noexcept(ranges::end(static_cast<const remove_reference_t<_Tp>&>(__t)))) |
| -> decltype(ranges::end(static_cast<const remove_reference_t<_Tp>&>(__t))) { |
| return ranges::end(static_cast<const remove_reference_t<_Tp>&>(__t)); |
| } |
| |
| template <class _Tp> |
| requires is_rvalue_reference_v<_Tp&&> |
| [[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Tp&& __t) const |
| noexcept(noexcept(ranges::end(static_cast<const _Tp&&>(__t)))) |
| -> decltype(ranges::end(static_cast<const _Tp&&>(__t))) { |
| return ranges::end(static_cast<const _Tp&&>(__t)); |
| } |
| }; |
| } // namespace __cend |
| |
| inline namespace __cpo { |
| inline constexpr auto cend = __cend::__fn{}; |
| } // namespace __cpo |
| } // namespace ranges |
| |
| #endif // _LIBCPP_STD_VER >= 20 |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| #endif // _LIBCPP___RANGES_ACCESS_H |