1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
|
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___CONCEPTS_ASSIGNABLE_H
#define _LIBCPP___CONCEPTS_ASSIGNABLE_H
#include <__concepts/common_reference_with.h>
#include <__concepts/same_as.h>
#include <__config>
#include <__type_traits/is_reference.h>
#include <__type_traits/make_const_lvalue_ref.h>
#include <__utility/forward.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_STD_VER > 17
// [concept.assignable]
template<class _Lhs, class _Rhs>
concept assignable_from =
is_lvalue_reference_v<_Lhs> &&
common_reference_with<__make_const_lvalue_ref<_Lhs>, __make_const_lvalue_ref<_Rhs>> &&
requires (_Lhs __lhs, _Rhs&& __rhs) {
{ __lhs = _VSTD::forward<_Rhs>(__rhs) } -> same_as<_Lhs>;
};
#endif // _LIBCPP_STD_VER > 17
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___CONCEPTS_ASSIGNABLE_H
|
