xref: /freebsd/contrib/llvm-project/libcxx/include/__ranges/dangling.h (revision fe6060f10f634930ff71b7c50291ddc610da2475)
1*fe6060f1SDimitry Andric // -*- C++ -*-
2*fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
3*fe6060f1SDimitry Andric //
4*fe6060f1SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5*fe6060f1SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
6*fe6060f1SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7*fe6060f1SDimitry Andric //
8*fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
9*fe6060f1SDimitry Andric 
10*fe6060f1SDimitry Andric #ifndef _LIBCPP___RANGES_DANGLING_H
11*fe6060f1SDimitry Andric #define _LIBCPP___RANGES_DANGLING_H
12*fe6060f1SDimitry Andric 
13*fe6060f1SDimitry Andric #include <__config>
14*fe6060f1SDimitry Andric #include <__ranges/access.h>
15*fe6060f1SDimitry Andric #include <__ranges/concepts.h>
16*fe6060f1SDimitry Andric #include <type_traits>
17*fe6060f1SDimitry Andric 
18*fe6060f1SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
19*fe6060f1SDimitry Andric #pragma GCC system_header
20*fe6060f1SDimitry Andric #endif
21*fe6060f1SDimitry Andric 
22*fe6060f1SDimitry Andric _LIBCPP_PUSH_MACROS
23*fe6060f1SDimitry Andric #include <__undef_macros>
24*fe6060f1SDimitry Andric 
25*fe6060f1SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD
26*fe6060f1SDimitry Andric 
27*fe6060f1SDimitry Andric #if !defined(_LIBCPP_HAS_NO_RANGES)
28*fe6060f1SDimitry Andric 
29*fe6060f1SDimitry Andric namespace ranges {
30*fe6060f1SDimitry Andric struct dangling {
31*fe6060f1SDimitry Andric   dangling() = default;
32*fe6060f1SDimitry Andric   _LIBCPP_HIDE_FROM_ABI constexpr dangling(auto&&...) noexcept {}
33*fe6060f1SDimitry Andric };
34*fe6060f1SDimitry Andric 
35*fe6060f1SDimitry Andric template <range _Rp>
36*fe6060f1SDimitry Andric using borrowed_iterator_t = _If<borrowed_range<_Rp>, iterator_t<_Rp>, dangling>;
37*fe6060f1SDimitry Andric 
38*fe6060f1SDimitry Andric // borrowed_subrange_t defined in <__ranges/subrange.h>
39*fe6060f1SDimitry Andric } // namespace ranges
40*fe6060f1SDimitry Andric 
41*fe6060f1SDimitry Andric #endif // !_LIBCPP_HAS_NO_RANGES
42*fe6060f1SDimitry Andric 
43*fe6060f1SDimitry Andric _LIBCPP_END_NAMESPACE_STD
44*fe6060f1SDimitry Andric 
45*fe6060f1SDimitry Andric _LIBCPP_POP_MACROS
46*fe6060f1SDimitry Andric 
47*fe6060f1SDimitry Andric #endif // _LIBCPP___RANGES_DANGLING_H
48