xref: /freebsd/contrib/llvm-project/libcxx/include/__ranges/owning_view.h (revision e6bfd18d21b225af6a0ed67ceeaf1293b7b9eba5)
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 #ifndef _LIBCPP___RANGES_OWNING_VIEW_H
10 #define _LIBCPP___RANGES_OWNING_VIEW_H
11 
12 #include <__concepts/constructible.h>
13 #include <__concepts/movable.h>
14 #include <__config>
15 #include <__ranges/access.h>
16 #include <__ranges/concepts.h>
17 #include <__ranges/data.h>
18 #include <__ranges/empty.h>
19 #include <__ranges/enable_borrowed_range.h>
20 #include <__ranges/size.h>
21 #include <__ranges/view_interface.h>
22 #include <__utility/move.h>
23 #include <type_traits>
24 
25 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
26 #  pragma GCC system_header
27 #endif
28 
29 _LIBCPP_BEGIN_NAMESPACE_STD
30 
31 #if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
32 
33 namespace ranges {
34   template<range _Rp>
35     requires movable<_Rp> && (!__is_std_initializer_list<remove_cvref_t<_Rp>>)
36   class owning_view : public view_interface<owning_view<_Rp>> {
37     _Rp __r_ = _Rp();
38 
39 public:
40     owning_view() requires default_initializable<_Rp> = default;
41     _LIBCPP_HIDE_FROM_ABI constexpr owning_view(_Rp&& __r) : __r_(std::move(__r)) {}
42 
43     owning_view(owning_view&&) = default;
44     owning_view& operator=(owning_view&&) = default;
45 
46     _LIBCPP_HIDE_FROM_ABI constexpr _Rp& base() & noexcept { return __r_; }
47     _LIBCPP_HIDE_FROM_ABI constexpr const _Rp& base() const& noexcept { return __r_; }
48     _LIBCPP_HIDE_FROM_ABI constexpr _Rp&& base() && noexcept { return std::move(__r_); }
49     _LIBCPP_HIDE_FROM_ABI constexpr const _Rp&& base() const&& noexcept { return std::move(__r_); }
50 
51     _LIBCPP_HIDE_FROM_ABI constexpr iterator_t<_Rp> begin() { return ranges::begin(__r_); }
52     _LIBCPP_HIDE_FROM_ABI constexpr sentinel_t<_Rp> end() { return ranges::end(__r_); }
53     _LIBCPP_HIDE_FROM_ABI constexpr auto begin() const requires range<const _Rp> { return ranges::begin(__r_); }
54     _LIBCPP_HIDE_FROM_ABI constexpr auto end() const requires range<const _Rp> { return ranges::end(__r_); }
55 
56     _LIBCPP_HIDE_FROM_ABI constexpr bool empty() requires requires { ranges::empty(__r_); }
57       { return ranges::empty(__r_); }
58     _LIBCPP_HIDE_FROM_ABI constexpr bool empty() const requires requires { ranges::empty(__r_); }
59       { return ranges::empty(__r_); }
60 
61     _LIBCPP_HIDE_FROM_ABI constexpr auto size() requires sized_range<_Rp>
62       { return ranges::size(__r_); }
63     _LIBCPP_HIDE_FROM_ABI constexpr auto size() const requires sized_range<const _Rp>
64       { return ranges::size(__r_); }
65 
66     _LIBCPP_HIDE_FROM_ABI constexpr auto data() requires contiguous_range<_Rp>
67       { return ranges::data(__r_); }
68     _LIBCPP_HIDE_FROM_ABI constexpr auto data() const requires contiguous_range<const _Rp>
69       { return ranges::data(__r_); }
70   };
71 
72   template<class _Tp>
73   inline constexpr bool enable_borrowed_range<owning_view<_Tp>> = enable_borrowed_range<_Tp>;
74 
75 } // namespace ranges
76 
77 #endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
78 
79 _LIBCPP_END_NAMESPACE_STD
80 
81 #endif // _LIBCPP___RANGES_OWNING_VIEW_H
82