xref: /freebsd/contrib/llvm-project/libcxx/include/__ranges/owning_view.h (revision 7ef62cebc2f965b0f640263e179276928885e33d)
1 // -*- C++ -*-
2 //===----------------------------------------------------------------------===//
3 //
4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5 // See https://llvm.org/LICENSE.txt for license information.
6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #ifndef _LIBCPP___RANGES_OWNING_VIEW_H
11 #define _LIBCPP___RANGES_OWNING_VIEW_H
12 
13 #include <__concepts/constructible.h>
14 #include <__concepts/movable.h>
15 #include <__config>
16 #include <__ranges/access.h>
17 #include <__ranges/concepts.h>
18 #include <__ranges/data.h>
19 #include <__ranges/empty.h>
20 #include <__ranges/enable_borrowed_range.h>
21 #include <__ranges/size.h>
22 #include <__ranges/view_interface.h>
23 #include <__utility/move.h>
24 #include <type_traits>
25 
26 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
27 #  pragma GCC system_header
28 #endif
29 
30 _LIBCPP_BEGIN_NAMESPACE_STD
31 
32 #if _LIBCPP_STD_VER > 17
33 
34 namespace ranges {
35   template<range _Rp>
36     requires movable<_Rp> && (!__is_std_initializer_list<remove_cvref_t<_Rp>>)
37   class owning_view : public view_interface<owning_view<_Rp>> {
38     _Rp __r_ = _Rp();
39 
40 public:
41     owning_view() requires default_initializable<_Rp> = default;
42     _LIBCPP_HIDE_FROM_ABI constexpr owning_view(_Rp&& __r) : __r_(std::move(__r)) {}
43 
44     owning_view(owning_view&&) = default;
45     owning_view& operator=(owning_view&&) = default;
46 
47     _LIBCPP_HIDE_FROM_ABI constexpr _Rp& base() & noexcept { return __r_; }
48     _LIBCPP_HIDE_FROM_ABI constexpr const _Rp& base() const& noexcept { return __r_; }
49     _LIBCPP_HIDE_FROM_ABI constexpr _Rp&& base() && noexcept { return std::move(__r_); }
50     _LIBCPP_HIDE_FROM_ABI constexpr const _Rp&& base() const&& noexcept { return std::move(__r_); }
51 
52     _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_Rp> begin() { return ranges::begin(__r_); }
53     _LIBCPP_HIDE_FROM_ABI constexpr sentinel_t<_Rp> end() { return ranges::end(__r_); }
54     _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const requires range<const _Rp> { return ranges::begin(__r_); }
55     _LIBCPP_HIDE_FROM_ABI constexpr auto end() const requires range<const _Rp> { return ranges::end(__r_); }
56 
57     _LIBCPP_HIDE_FROM_ABI constexpr bool empty() requires requires { ranges::empty(__r_); }
58       { return ranges::empty(__r_); }
59     _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const requires requires { ranges::empty(__r_); }
60       { return ranges::empty(__r_); }
61 
62     _LIBCPP_HIDE_FROM_ABI constexpr auto size() requires sized_range<_Rp>
63       { return ranges::size(__r_); }
64     _LIBCPP_HIDE_FROM_ABI constexpr auto size() const requires sized_range<const _Rp>
65       { return ranges::size(__r_); }
66 
67     _LIBCPP_HIDE_FROM_ABI constexpr auto data() requires contiguous_range<_Rp>
68       { return ranges::data(__r_); }
69     _LIBCPP_HIDE_FROM_ABI constexpr auto data() const requires contiguous_range<const _Rp>
70       { return ranges::data(__r_); }
71   };
72   _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(owning_view);
73 
74   template<class _Tp>
75   inline constexpr bool enable_borrowed_range<owning_view<_Tp>> = enable_borrowed_range<_Tp>;
76 
77 } // namespace ranges
78 
79 #endif // _LIBCPP_STD_VER > 17
80 
81 _LIBCPP_END_NAMESPACE_STD
82 
83 #endif // _LIBCPP___RANGES_OWNING_VIEW_H
84