xref: /openbsd-src/gnu/llvm/libcxx/include/__iterator/projected.h (revision 4bdff4bed0e3d54e55670334c7d0077db4170f86)
176d0caaeSpatrick // -*- C++ -*-
276d0caaeSpatrick //===----------------------------------------------------------------------===//
376d0caaeSpatrick //
476d0caaeSpatrick // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
576d0caaeSpatrick // See https://llvm.org/LICENSE.txt for license information.
676d0caaeSpatrick // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
776d0caaeSpatrick //
876d0caaeSpatrick //===----------------------------------------------------------------------===//
9*4bdff4beSrobert 
1076d0caaeSpatrick #ifndef _LIBCPP___ITERATOR_PROJECTED_H
1176d0caaeSpatrick #define _LIBCPP___ITERATOR_PROJECTED_H
1276d0caaeSpatrick 
1376d0caaeSpatrick #include <__config>
1476d0caaeSpatrick #include <__iterator/concepts.h>
1576d0caaeSpatrick #include <__iterator/incrementable_traits.h>
16*4bdff4beSrobert #include <__type_traits/remove_cvref.h>
1776d0caaeSpatrick 
1876d0caaeSpatrick #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
1976d0caaeSpatrick #  pragma GCC system_header
2076d0caaeSpatrick #endif
2176d0caaeSpatrick 
2276d0caaeSpatrick _LIBCPP_BEGIN_NAMESPACE_STD
2376d0caaeSpatrick 
24*4bdff4beSrobert #if _LIBCPP_STD_VER > 17
2576d0caaeSpatrick 
2676d0caaeSpatrick template<indirectly_readable _It, indirectly_regular_unary_invocable<_It> _Proj>
2776d0caaeSpatrick struct projected {
2876d0caaeSpatrick   using value_type = remove_cvref_t<indirect_result_t<_Proj&, _It>>;
2976d0caaeSpatrick   indirect_result_t<_Proj&, _It> operator*() const; // not defined
3076d0caaeSpatrick };
3176d0caaeSpatrick 
3276d0caaeSpatrick template<weakly_incrementable _It, class _Proj>
3376d0caaeSpatrick struct incrementable_traits<projected<_It, _Proj>> {
3476d0caaeSpatrick   using difference_type = iter_difference_t<_It>;
3576d0caaeSpatrick };
3676d0caaeSpatrick 
37*4bdff4beSrobert #endif // _LIBCPP_STD_VER > 17
3876d0caaeSpatrick 
3976d0caaeSpatrick _LIBCPP_END_NAMESPACE_STD
4076d0caaeSpatrick 
4176d0caaeSpatrick #endif // _LIBCPP___ITERATOR_PROJECTED_H
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