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//===----------------------------------------------------------------------===//
//
// 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___ALGORITHM_RANGES_FOR_EACH_N_H
#define _LIBCPP___ALGORITHM_RANGES_FOR_EACH_N_H
#include <__algorithm/in_fun_result.h>
#include <__config>
#include <__functional/identity.h>
#include <__functional/invoke.h>
#include <__iterator/concepts.h>
#include <__iterator/incrementable_traits.h>
#include <__iterator/iterator_traits.h>
#include <__iterator/projected.h>
#include <__ranges/concepts.h>
#include <__ranges/dangling.h>
#include <__utility/move.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
_LIBCPP_BEGIN_NAMESPACE_STD
namespace ranges {
template <class _Iter, class _Func>
using for_each_n_result = in_fun_result<_Iter, _Func>;
namespace __for_each_n {
struct __fn {
template <input_iterator _Iter,
class _Proj = identity,
indirectly_unary_invocable<projected<_Iter, _Proj>> _Func>
_LIBCPP_HIDE_FROM_ABI constexpr
for_each_n_result<_Iter, _Func> operator()(_Iter __first,
iter_difference_t<_Iter> __count,
_Func __func,
_Proj __proj = {}) const {
while (__count-- > 0) {
std::invoke(__func, std::invoke(__proj, *__first));
++__first;
}
return {std::move(__first), std::move(__func)};
}
};
} // namespace __for_each_n
inline namespace __cpo {
inline constexpr auto for_each_n = __for_each_n::__fn{};
} // namespace __cpo
} // namespace ranges
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES)
#endif // _LIBCPP___ALGORITHM_RANGES_FOR_EACH_N_H