xref: /freebsd-src/contrib/llvm-project/libcxx/include/__algorithm/ranges_copy_n.h (revision b3edf4467982447620505a28fc82e38a414c07dc)
181ad6265SDimitry Andric //===----------------------------------------------------------------------===//
281ad6265SDimitry Andric //
381ad6265SDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
481ad6265SDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
581ad6265SDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
681ad6265SDimitry Andric //
781ad6265SDimitry Andric //===----------------------------------------------------------------------===//
881ad6265SDimitry Andric 
981ad6265SDimitry Andric #ifndef _LIBCPP___ALGORITHM_RANGES_COPY_N_H
1081ad6265SDimitry Andric #define _LIBCPP___ALGORITHM_RANGES_COPY_N_H
1181ad6265SDimitry Andric 
1281ad6265SDimitry Andric #include <__algorithm/copy.h>
1381ad6265SDimitry Andric #include <__algorithm/in_out_result.h>
14bdd1243dSDimitry Andric #include <__algorithm/iterator_operations.h>
1581ad6265SDimitry Andric #include <__algorithm/ranges_copy.h>
1681ad6265SDimitry Andric #include <__config>
1781ad6265SDimitry Andric #include <__functional/identity.h>
1881ad6265SDimitry Andric #include <__iterator/concepts.h>
1981ad6265SDimitry Andric #include <__iterator/incrementable_traits.h>
2081ad6265SDimitry Andric #include <__iterator/unreachable_sentinel.h>
2181ad6265SDimitry Andric #include <__iterator/wrap_iter.h>
2281ad6265SDimitry Andric #include <__utility/move.h>
2381ad6265SDimitry Andric 
2481ad6265SDimitry Andric #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
2581ad6265SDimitry Andric #  pragma GCC system_header
2681ad6265SDimitry Andric #endif
2781ad6265SDimitry Andric 
28*b3edf446SDimitry Andric _LIBCPP_PUSH_MACROS
29*b3edf446SDimitry Andric #include <__undef_macros>
30*b3edf446SDimitry Andric 
3181ad6265SDimitry Andric _LIBCPP_BEGIN_NAMESPACE_STD
3281ad6265SDimitry Andric 
3306c3fb27SDimitry Andric #if _LIBCPP_STD_VER >= 20
3481ad6265SDimitry Andric 
3581ad6265SDimitry Andric namespace ranges {
3681ad6265SDimitry Andric 
3781ad6265SDimitry Andric template <class _Ip, class _Op>
3881ad6265SDimitry Andric using copy_n_result = in_out_result<_Ip, _Op>;
3981ad6265SDimitry Andric 
4081ad6265SDimitry Andric namespace __copy_n {
4181ad6265SDimitry Andric struct __fn {
4281ad6265SDimitry Andric   template <class _InIter, class _DiffType, class _OutIter>
4306c3fb27SDimitry Andric   _LIBCPP_HIDE_FROM_ABI constexpr static copy_n_result<_InIter, _OutIter>
__go__fn4406c3fb27SDimitry Andric   __go(_InIter __first, _DiffType __n, _OutIter __result) {
4581ad6265SDimitry Andric     while (__n != 0) {
4681ad6265SDimitry Andric       *__result = *__first;
4781ad6265SDimitry Andric       ++__first;
4881ad6265SDimitry Andric       ++__result;
4981ad6265SDimitry Andric       --__n;
5081ad6265SDimitry Andric     }
5181ad6265SDimitry Andric     return {std::move(__first), std::move(__result)};
5281ad6265SDimitry Andric   }
5381ad6265SDimitry Andric 
5481ad6265SDimitry Andric   template <random_access_iterator _InIter, class _DiffType, random_access_iterator _OutIter>
5506c3fb27SDimitry Andric   _LIBCPP_HIDE_FROM_ABI constexpr static copy_n_result<_InIter, _OutIter>
__go__fn5606c3fb27SDimitry Andric   __go(_InIter __first, _DiffType __n, _OutIter __result) {
57bdd1243dSDimitry Andric     auto __ret = std::__copy<_RangeAlgPolicy>(__first, __first + __n, __result);
5881ad6265SDimitry Andric     return {__ret.first, __ret.second};
5981ad6265SDimitry Andric   }
6081ad6265SDimitry Andric 
6181ad6265SDimitry Andric   template <input_iterator _Ip, weakly_incrementable _Op>
6281ad6265SDimitry Andric     requires indirectly_copyable<_Ip, _Op>
6306c3fb27SDimitry Andric   _LIBCPP_HIDE_FROM_ABI constexpr copy_n_result<_Ip, _Op>
operator__fn6406c3fb27SDimitry Andric   operator()(_Ip __first, iter_difference_t<_Ip> __n, _Op __result) const {
6581ad6265SDimitry Andric     return __go(std::move(__first), __n, std::move(__result));
6681ad6265SDimitry Andric   }
6781ad6265SDimitry Andric };
6881ad6265SDimitry Andric } // namespace __copy_n
6981ad6265SDimitry Andric 
7081ad6265SDimitry Andric inline namespace __cpo {
7181ad6265SDimitry Andric inline constexpr auto copy_n = __copy_n::__fn{};
7281ad6265SDimitry Andric } // namespace __cpo
7381ad6265SDimitry Andric } // namespace ranges
7481ad6265SDimitry Andric 
7506c3fb27SDimitry Andric #endif // _LIBCPP_STD_VER >= 20
7681ad6265SDimitry Andric 
7781ad6265SDimitry Andric _LIBCPP_END_NAMESPACE_STD
7881ad6265SDimitry Andric 
79*b3edf446SDimitry Andric _LIBCPP_POP_MACROS
80*b3edf446SDimitry Andric 
8181ad6265SDimitry Andric #endif // _LIBCPP___ALGORITHM_RANGES_COPY_N_H
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