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1//===----------------------------------------------------------------------===//
2//
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
6//
7//===----------------------------------------------------------------------===//
8
9#ifndef _LIBCPP___RANGES_AS_RVALUE_H
10#define _LIBCPP___RANGES_AS_RVALUE_H
11
12#include <__concepts/constructible.h>
13#include <__concepts/same_as.h>
14#include <__config>
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>
26
27#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
28# pragma GCC system_header
29#endif
30
31_LIBCPP_PUSH_MACROS
32#include <__undef_macros>
33
34#if _LIBCPP_STD_VER >= 23
35
36_LIBCPP_BEGIN_NAMESPACE_STD
37
38namespace ranges {
39template <view _View>
40 requires input_range<_View>
41class as_rvalue_view : public view_interface<as_rvalue_view<_View>> {
42 _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
43
44public:
45 _LIBCPP_HIDE_FROM_ABI as_rvalue_view()
46 requires default_initializable<_View>
47 = default;
48
49 _LIBCPP_HIDE_FROM_ABI constexpr explicit as_rvalue_view(_View __base) : __base_(std::move(__base)) {}
50
51 _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
52 requires copy_constructible<_View>
53 {
54 return __base_;
55 }
56
57 _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
58
59 _LIBCPP_HIDE_FROM_ABI constexpr auto begin()
60 requires(!__simple_view<_View>)
61 {
62 return move_iterator(ranges::begin(__base_));
63 }
64
65 _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
66 requires range<const _View>
67 {
68 return move_iterator(ranges::begin(__base_));
69 }
70
71 _LIBCPP_HIDE_FROM_ABI constexpr auto end()
72 requires(!__simple_view<_View>)
73 {
74 if constexpr (common_range<_View>) {
75 return move_iterator(ranges::end(__base_));
76 } else {
77 return move_sentinel(ranges::end(__base_));
78 }
79 }
80
81 _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
82 requires range<const _View>
83 {
84 if constexpr (common_range<const _View>) {
85 return move_iterator(ranges::end(__base_));
86 } else {
87 return move_sentinel(ranges::end(__base_));
88 }
89 }
90
91 _LIBCPP_HIDE_FROM_ABI constexpr auto size()
92 requires sized_range<_View>
93 {
94 return ranges::size(__base_);
95 }
96
97 _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
98 requires sized_range<const _View>
99 {
100 return ranges::size(__base_);
101 }
102};
103
104template <class _Range>
105as_rvalue_view(_Range&&) -> as_rvalue_view<views::all_t<_Range>>;
106
107template <class _View>
108inline constexpr bool enable_borrowed_range<as_rvalue_view<_View>> = enable_borrowed_range<_View>;
109
110namespace views {
111namespace __as_rvalue {
112struct __fn : __range_adaptor_closure<__fn> {
113 template <class _Range>
114 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto
115 operator()(_Range&& __range) noexcept(noexcept(as_rvalue_view(std::forward<_Range>(__range))))
116 -> decltype(/*--------------------------*/ as_rvalue_view(std::forward<_Range>(__range))) {
117 return /*---------------------------------*/ as_rvalue_view(std::forward<_Range>(__range));
118 }
119
120 template <class _Range>
121 requires same_as<range_rvalue_reference_t<_Range>, range_reference_t<_Range>>
122 [[nodiscard]] _LIBCPP_HIDE_FROM_ABI static constexpr auto
123 operator()(_Range&& __range) noexcept(noexcept(views::all(std::forward<_Range>(__range))))
124 -> decltype(/*--------------------------*/ views::all(std::forward<_Range>(__range))) {
125 return /*---------------------------------*/ views::all(std::forward<_Range>(__range));
126 }
127};
128} // namespace __as_rvalue
129
130inline namespace __cpo {
131inline constexpr auto as_rvalue = __as_rvalue::__fn{};
132} // namespace __cpo
133} // namespace views
134} // namespace ranges
135
136_LIBCPP_END_NAMESPACE_STD
137
138#endif // _LIBCPP_STD_VER >= 23
139
140_LIBCPP_POP_MACROS
141
142#endif // _LIBCPP___RANGES_AS_RVALUE_H