xref: /freebsd-src/contrib/llvm-project/libcxx/include/__iterator/projected.h (revision bdd1243df58e60e85101c09001d9812a789b6bc4)
1fe6060f1SDimitry Andric // -*- C++ -*-
2fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
3fe6060f1SDimitry Andric //
4fe6060f1SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5fe6060f1SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
6fe6060f1SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7fe6060f1SDimitry Andric //
8fe6060f1SDimitry Andric //===----------------------------------------------------------------------===//
9*bdd1243dSDimitry Andric 
10fe6060f1SDimitry Andric #ifndef _LIBCPP___ITERATOR_PROJECTED_H
11fe6060f1SDimitry Andric #define _LIBCPP___ITERATOR_PROJECTED_H
12fe6060f1SDimitry Andric 
13fe6060f1SDimitry Andric #include <__config>
14fe6060f1SDimitry Andric #include <__iterator/concepts.h>
15fe6060f1SDimitry Andric #include <__iterator/incrementable_traits.h>
16*bdd1243dSDimitry Andric #include <__type_traits/remove_cvref.h>
17fe6060f1SDimitry Andric 
18fe6060f1SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
19fe6060f1SDimitry Andric #  pragma GCC system_header
20fe6060f1SDimitry Andric #endif
21fe6060f1SDimitry Andric 
22fe6060f1SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD
23fe6060f1SDimitry Andric 
2481ad6265SDimitry Andric #if _LIBCPP_STD_VER > 17
25fe6060f1SDimitry Andric 
26fe6060f1SDimitry Andric template<indirectly_readable _It, indirectly_regular_unary_invocable<_It> _Proj>
27fe6060f1SDimitry Andric struct projected {
28fe6060f1SDimitry Andric   using value_type = remove_cvref_t<indirect_result_t<_Proj&, _It>>;
29fe6060f1SDimitry Andric   indirect_result_t<_Proj&, _It> operator*() const; // not defined
30fe6060f1SDimitry Andric };
31fe6060f1SDimitry Andric 
32fe6060f1SDimitry Andric template<weakly_incrementable _It, class _Proj>
33fe6060f1SDimitry Andric struct incrementable_traits<projected<_It, _Proj>> {
34fe6060f1SDimitry Andric   using difference_type = iter_difference_t<_It>;
35fe6060f1SDimitry Andric };
36fe6060f1SDimitry Andric 
3781ad6265SDimitry Andric #endif // _LIBCPP_STD_VER > 17
38fe6060f1SDimitry Andric 
39fe6060f1SDimitry Andric _LIBCPP_END_NAMESPACE_STD
40fe6060f1SDimitry Andric 
41fe6060f1SDimitry Andric #endif // _LIBCPP___ITERATOR_PROJECTED_H
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