1 //===----------------------------------------------------------------------===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 #ifndef _LIBCPP___RANGES_AS_RVALUE_H
10 #define _LIBCPP___RANGES_AS_RVALUE_H
12 #include <__concepts/constructible.h>
13 #include <__concepts/same_as.h>
15 #include <__iterator/move_iterator.h>
16 #include <__iterator/move_sentinel.h>
17 #include <__ranges/access.h>
18 #include <__ranges/all.h>
19 #include <__ranges/concepts.h>
20 #include <__ranges/enable_borrowed_range.h>
21 #include <__ranges/range_adaptor.h>
22 #include <__ranges/size.h>
23 #include <__ranges/view_interface.h>
24 #include <__utility/forward.h>
25 #include <__utility/move.h>
27 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
28 # pragma GCC system_header
31 #if _LIBCPP_STD_VER >= 23
33 _LIBCPP_BEGIN_NAMESPACE_STD
37 requires input_range<_View>
38 class as_rvalue_view : public view_interface<as_rvalue_view<_View>> {
39 _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
42 _LIBCPP_HIDE_FROM_ABI as_rvalue_view()
43 requires default_initializable<_View>
46 _LIBCPP_HIDE_FROM_ABI constexpr explicit as_rvalue_view(_View __base) : __base_(std::move(__base)) {}
48 _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
49 requires copy_constructible<_View>
54 _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
56 _LIBCPP_HIDE_FROM_ABI constexpr auto begin()
57 requires(!__simple_view<_View>)
59 return move_iterator(ranges::begin(__base_));
62 _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
63 requires range<const _View>
65 return move_iterator(ranges::begin(__base_));
68 _LIBCPP_HIDE_FROM_ABI constexpr auto end()
69 requires(!__simple_view<_View>)
71 if constexpr (common_range<_View>) {
72 return move_iterator(ranges::end(__base_));
74 return move_sentinel(ranges::end(__base_));
78 _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
79 requires range<const _View>
81 if constexpr (common_range<const _View>) {
82 return move_iterator(ranges::end(__base_));
84 return move_sentinel(ranges::end(__base_));
88 _LIBCPP_HIDE_FROM_ABI constexpr auto size()
89 requires sized_range<_View>
91 return ranges::size(__base_);
94 _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
95 requires sized_range<const _View>
97 return ranges::size(__base_);
101 template <class _Range>
102 as_rvalue_view(_Range&&) -> as_rvalue_view<views::all_t<_Range>>;
104 template <class _View>
105 inline constexpr bool enable_borrowed_range<as_rvalue_view<_View>> = enable_borrowed_range<_View>;
108 namespace __as_rvalue {
109 struct __fn : __range_adaptor_closure<__fn> {
110 template <class _Range>
111 _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const
112 noexcept(noexcept(/**/ as_rvalue_view(std::forward<_Range>(__range))))
113 -> decltype(/*--*/ as_rvalue_view(std::forward<_Range>(__range))) {
114 return /*-------------*/ as_rvalue_view(std::forward<_Range>(__range));
117 template <class _Range>
118 requires same_as<range_rvalue_reference_t<_Range>, range_reference_t<_Range>>
119 _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const
120 noexcept(noexcept(/**/ views::all(std::forward<_Range>(__range))))
121 -> decltype(/*--*/ views::all(std::forward<_Range>(__range))) {
122 return /*-------------*/ views::all(std::forward<_Range>(__range));
125 } // namespace __as_rvalue
127 inline namespace __cpo {
128 constexpr auto as_rvalue = __as_rvalue::__fn{};
131 } // namespace ranges
133 _LIBCPP_END_NAMESPACE_STD
135 #endif // _LIBCPP_STD_VER >= 23
137 #endif // _LIBCPP___RANGES_AS_RVALUE_H