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
42
43
44
45
46
47
48
49
50
51
|
// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// 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___RANGES_ENABLE_VIEW_H
#define _LIBCPP___RANGES_ENABLE_VIEW_H
#include <__concepts/derived_from.h>
#include <__concepts/same_as.h>
#include <__config>
#include <__type_traits/is_class.h>
#include <__type_traits/is_convertible.h>
#include <__type_traits/remove_cv.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
#if _LIBCPP_STD_VER >= 20
namespace ranges {
struct view_base {};
template <class _Derived>
requires is_class_v<_Derived> && same_as<_Derived, remove_cv_t<_Derived>>
class view_interface;
template <class _Op, class _Yp>
requires is_convertible_v<_Op*, view_interface<_Yp>*>
void __is_derived_from_view_interface(const _Op*, const view_interface<_Yp>*);
template <class _Tp>
inline constexpr bool enable_view = derived_from<_Tp, view_base> || requires {
ranges::__is_derived_from_view_interface((_Tp*)nullptr, (_Tp*)nullptr);
};
} // namespace ranges
#endif // _LIBCPP_STD_VER >= 20
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___RANGES_ENABLE_VIEW_H
|
