1//===----------------------------------------------------------------------===//
 2//
 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 4// See https://llvm.org/LICENSE.txt for license information.
 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 6//
 7//===----------------------------------------------------------------------===//
 8
 9#ifndef _LIBCPP___ALGORITHM_RANGES_FOR_EACH_N_H
10#define _LIBCPP___ALGORITHM_RANGES_FOR_EACH_N_H
11
12#include <__algorithm/for_each_n.h>
13#include <__algorithm/in_fun_result.h>
14#include <__config>
15#include <__functional/identity.h>
16#include <__iterator/concepts.h>
17#include <__iterator/incrementable_traits.h>
18#include <__iterator/iterator_traits.h>
19#include <__iterator/projected.h>
20#include <__ranges/concepts.h>
21#include <__utility/move.h>
22
23#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
24#  pragma GCC system_header
25#endif
26
27_LIBCPP_PUSH_MACROS
28#include <__undef_macros>
29
30#if _LIBCPP_STD_VER >= 20
31
32_LIBCPP_BEGIN_NAMESPACE_STD
33
34namespace ranges {
35
36template <class _Iter, class _Func>
37using for_each_n_result = in_fun_result<_Iter, _Func>;
38
39struct __for_each_n {
40  template <input_iterator _Iter, class _Proj = identity, indirectly_unary_invocable<projected<_Iter, _Proj>> _Func>
41  _LIBCPP_HIDE_FROM_ABI constexpr for_each_n_result<_Iter, _Func>
42  operator()(_Iter __first, iter_difference_t<_Iter> __count, _Func __func, _Proj __proj = {}) const {
43    auto __last = std::__for_each_n(std::move(__first), __count, __func, __proj);
44    return {std::move(__last), std::move(__func)};
45  }
46};
47
48inline namespace __cpo {
49inline constexpr auto for_each_n = __for_each_n{};
50} // namespace __cpo
51} // namespace ranges
52
53_LIBCPP_END_NAMESPACE_STD
54
55#endif // _LIBCPP_STD_VER >= 20
56
57_LIBCPP_POP_MACROS
58
59#endif // _LIBCPP___ALGORITHM_RANGES_FOR_EACH_N_H