xref: /openbsd-src/gnu/llvm/libcxx/include/__ranges/as_rvalue_view.h (revision 4bdff4bed0e3d54e55670334c7d0077db4170f86)
1*4bdff4beSrobert //===----------------------------------------------------------------------===//
2*4bdff4beSrobert //
3*4bdff4beSrobert // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*4bdff4beSrobert // See https://llvm.org/LICENSE.txt for license information.
5*4bdff4beSrobert // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*4bdff4beSrobert //
7*4bdff4beSrobert //===----------------------------------------------------------------------===//
8*4bdff4beSrobert 
9*4bdff4beSrobert #ifndef _LIBCPP___RANGES_AS_RVALUE_H
10*4bdff4beSrobert #define _LIBCPP___RANGES_AS_RVALUE_H
11*4bdff4beSrobert 
12*4bdff4beSrobert #include <__concepts/constructible.h>
13*4bdff4beSrobert #include <__concepts/same_as.h>
14*4bdff4beSrobert #include <__config>
15*4bdff4beSrobert #include <__iterator/move_iterator.h>
16*4bdff4beSrobert #include <__iterator/move_sentinel.h>
17*4bdff4beSrobert #include <__ranges/access.h>
18*4bdff4beSrobert #include <__ranges/all.h>
19*4bdff4beSrobert #include <__ranges/concepts.h>
20*4bdff4beSrobert #include <__ranges/enable_borrowed_range.h>
21*4bdff4beSrobert #include <__ranges/range_adaptor.h>
22*4bdff4beSrobert #include <__ranges/size.h>
23*4bdff4beSrobert #include <__ranges/view_interface.h>
24*4bdff4beSrobert #include <__utility/forward.h>
25*4bdff4beSrobert #include <__utility/move.h>
26*4bdff4beSrobert 
27*4bdff4beSrobert #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
28*4bdff4beSrobert #  pragma GCC system_header
29*4bdff4beSrobert #endif
30*4bdff4beSrobert 
31*4bdff4beSrobert #if _LIBCPP_STD_VER >= 23
32*4bdff4beSrobert 
33*4bdff4beSrobert _LIBCPP_BEGIN_NAMESPACE_STD
34*4bdff4beSrobert 
35*4bdff4beSrobert namespace ranges {
36*4bdff4beSrobert template <view _View>
37*4bdff4beSrobert   requires input_range<_View>
38*4bdff4beSrobert class as_rvalue_view : public view_interface<as_rvalue_view<_View>> {
39*4bdff4beSrobert   _LIBCPP_NO_UNIQUE_ADDRESS _View __base_ = _View();
40*4bdff4beSrobert 
41*4bdff4beSrobert public:
42*4bdff4beSrobert   _LIBCPP_HIDE_FROM_ABI as_rvalue_view()
43*4bdff4beSrobert     requires default_initializable<_View>
44*4bdff4beSrobert   = default;
45*4bdff4beSrobert 
as_rvalue_view(_View __base)46*4bdff4beSrobert   _LIBCPP_HIDE_FROM_ABI constexpr explicit as_rvalue_view(_View __base) : __base_(std::move(__base)) {}
47*4bdff4beSrobert 
base()48*4bdff4beSrobert   _LIBCPP_HIDE_FROM_ABI constexpr _View base() const&
49*4bdff4beSrobert     requires copy_constructible<_View>
50*4bdff4beSrobert   {
51*4bdff4beSrobert     return __base_;
52*4bdff4beSrobert   }
53*4bdff4beSrobert 
base()54*4bdff4beSrobert   _LIBCPP_HIDE_FROM_ABI constexpr _View base() && { return std::move(__base_); }
55*4bdff4beSrobert 
begin()56*4bdff4beSrobert   _LIBCPP_HIDE_FROM_ABI constexpr auto begin()
57*4bdff4beSrobert     requires(!__simple_view<_View>)
58*4bdff4beSrobert   {
59*4bdff4beSrobert     return move_iterator(ranges::begin(__base_));
60*4bdff4beSrobert   }
61*4bdff4beSrobert 
begin()62*4bdff4beSrobert   _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const
63*4bdff4beSrobert     requires range<const _View>
64*4bdff4beSrobert   {
65*4bdff4beSrobert     return move_iterator(ranges::begin(__base_));
66*4bdff4beSrobert   }
67*4bdff4beSrobert 
end()68*4bdff4beSrobert   _LIBCPP_HIDE_FROM_ABI constexpr auto end()
69*4bdff4beSrobert     requires(!__simple_view<_View>)
70*4bdff4beSrobert   {
71*4bdff4beSrobert     if constexpr (common_range<_View>) {
72*4bdff4beSrobert       return move_iterator(ranges::end(__base_));
73*4bdff4beSrobert     } else {
74*4bdff4beSrobert       return move_sentinel(ranges::end(__base_));
75*4bdff4beSrobert     }
76*4bdff4beSrobert   }
77*4bdff4beSrobert 
end()78*4bdff4beSrobert   _LIBCPP_HIDE_FROM_ABI constexpr auto end() const
79*4bdff4beSrobert     requires range<const _View>
80*4bdff4beSrobert   {
81*4bdff4beSrobert     if constexpr (common_range<const _View>) {
82*4bdff4beSrobert       return move_iterator(ranges::end(__base_));
83*4bdff4beSrobert     } else {
84*4bdff4beSrobert       return move_sentinel(ranges::end(__base_));
85*4bdff4beSrobert     }
86*4bdff4beSrobert   }
87*4bdff4beSrobert 
size()88*4bdff4beSrobert   _LIBCPP_HIDE_FROM_ABI constexpr auto size()
89*4bdff4beSrobert     requires sized_range<_View>
90*4bdff4beSrobert   {
91*4bdff4beSrobert     return ranges::size(__base_);
92*4bdff4beSrobert   }
93*4bdff4beSrobert 
size()94*4bdff4beSrobert   _LIBCPP_HIDE_FROM_ABI constexpr auto size() const
95*4bdff4beSrobert     requires sized_range<const _View>
96*4bdff4beSrobert   {
97*4bdff4beSrobert     return ranges::size(__base_);
98*4bdff4beSrobert   }
99*4bdff4beSrobert };
100*4bdff4beSrobert 
101*4bdff4beSrobert template <class _Range>
102*4bdff4beSrobert as_rvalue_view(_Range&&) -> as_rvalue_view<views::all_t<_Range>>;
103*4bdff4beSrobert 
104*4bdff4beSrobert template <class _View>
105*4bdff4beSrobert inline constexpr bool enable_borrowed_range<as_rvalue_view<_View>> = enable_borrowed_range<_View>;
106*4bdff4beSrobert 
107*4bdff4beSrobert namespace views {
108*4bdff4beSrobert namespace __as_rvalue {
109*4bdff4beSrobert struct __fn : __range_adaptor_closure<__fn> {
110*4bdff4beSrobert   template <class _Range>
111*4bdff4beSrobert   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const
112*4bdff4beSrobert       noexcept(noexcept(/**/ as_rvalue_view(std::forward<_Range>(__range))))
113*4bdff4beSrobert           -> decltype(/*--*/ as_rvalue_view(std::forward<_Range>(__range))) {
114*4bdff4beSrobert     return /*-------------*/ as_rvalue_view(std::forward<_Range>(__range));
115*4bdff4beSrobert   }
116*4bdff4beSrobert 
117*4bdff4beSrobert   template <class _Range>
118*4bdff4beSrobert     requires same_as<range_rvalue_reference_t<_Range>, range_reference_t<_Range>>
119*4bdff4beSrobert   _LIBCPP_NODISCARD_EXT _LIBCPP_HIDE_FROM_ABI constexpr auto operator()(_Range&& __range) const
120*4bdff4beSrobert       noexcept(noexcept(/**/ views::all(std::forward<_Range>(__range))))
121*4bdff4beSrobert           -> decltype(/*--*/ views::all(std::forward<_Range>(__range))) {
122*4bdff4beSrobert     return /*-------------*/ views::all(std::forward<_Range>(__range));
123*4bdff4beSrobert   }
124*4bdff4beSrobert };
125*4bdff4beSrobert } // namespace __as_rvalue
126*4bdff4beSrobert 
127*4bdff4beSrobert inline namespace __cpo {
128*4bdff4beSrobert constexpr auto as_rvalue = __as_rvalue::__fn{};
129*4bdff4beSrobert } // namespace __cpo
130*4bdff4beSrobert } // namespace views
131*4bdff4beSrobert } // namespace ranges
132*4bdff4beSrobert 
133*4bdff4beSrobert _LIBCPP_END_NAMESPACE_STD
134*4bdff4beSrobert 
135*4bdff4beSrobert #endif // _LIBCPP_STD_VER >= 23
136*4bdff4beSrobert 
137*4bdff4beSrobert #endif // _LIBCPP___RANGES_AS_RVALUE_H
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