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___MEMORY_CONCEPTS_H
11#define _LIBCPP___MEMORY_CONCEPTS_H
12
13#include <__concepts/same_as.h>
14#include <__config>
15#include <__iterator/concepts.h>
16#include <__iterator/iterator_traits.h>
17#include <__iterator/readable_traits.h>
18#include <__ranges/access.h>
19#include <__ranges/concepts.h>
20#include <__type_traits/is_reference.h>
21#include <__type_traits/remove_cvref.h>
22#include <__type_traits/remove_reference.h> // TODO(modules): This should not be required
23
24#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
25# pragma GCC system_header
26#endif
27
28_LIBCPP_BEGIN_NAMESPACE_STD
29
30#if _LIBCPP_STD_VER >= 20
31
32namespace ranges {
33
34// [special.mem.concepts]
35
36// This concept ensures that uninitialized algorithms can construct an object
37// at the address pointed-to by the iterator, which requires an lvalue.
38template <class _Ip>
39concept __nothrow_input_iterator =
40 input_iterator<_Ip> && is_lvalue_reference_v<iter_reference_t<_Ip>> &&
41 same_as<remove_cvref_t<iter_reference_t<_Ip>>, iter_value_t<_Ip>>;
42
43template <class _Sp, class _Ip>
44concept __nothrow_sentinel_for = sentinel_for<_Sp, _Ip>;
45
46template <class _Rp>
47concept __nothrow_input_range =
48 range<_Rp> && __nothrow_input_iterator<iterator_t<_Rp>> && __nothrow_sentinel_for<sentinel_t<_Rp>, iterator_t<_Rp>>;
49
50template <class _Ip>
51concept __nothrow_forward_iterator =
52 __nothrow_input_iterator<_Ip> && forward_iterator<_Ip> && __nothrow_sentinel_for<_Ip, _Ip>;
53
54template <class _Rp>
55concept __nothrow_forward_range = __nothrow_input_range<_Rp> && __nothrow_forward_iterator<iterator_t<_Rp>>;
56
57} // namespace ranges
58
59#endif // _LIBCPP_STD_VER >= 20
60
61_LIBCPP_END_NAMESPACE_STD
62
63#endif // _LIBCPP___MEMORY_CONCEPTS_H
64