| //===----------------------------------------------------------------------===// |
| // |
| // 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_COPY_N_H |
| #define _LIBCPP___ALGORITHM_RANGES_COPY_N_H |
| |
| #include <__algorithm/copy.h> |
| #include <__algorithm/in_out_result.h> |
| #include <__algorithm/ranges_copy.h> |
| #include <__config> |
| #include <__functional/identity.h> |
| #include <__iterator/concepts.h> |
| #include <__iterator/incrementable_traits.h> |
| #include <__iterator/unreachable_sentinel.h> |
| #include <__iterator/wrap_iter.h> |
| #include <__utility/move.h> |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| # pragma GCC system_header |
| #endif |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| #if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES) |
| |
| namespace ranges { |
| |
| template <class _Ip, class _Op> |
| using copy_n_result = in_out_result<_Ip, _Op>; |
| |
| namespace __copy_n { |
| struct __fn { |
| |
| template <class _InIter, class _DiffType, class _OutIter> |
| _LIBCPP_HIDE_FROM_ABI constexpr static |
| copy_n_result<_InIter, _OutIter> __go(_InIter __first, _DiffType __n, _OutIter __result) { |
| while (__n != 0) { |
| *__result = *__first; |
| ++__first; |
| ++__result; |
| --__n; |
| } |
| return {std::move(__first), std::move(__result)}; |
| } |
| |
| template <random_access_iterator _InIter, class _DiffType, random_access_iterator _OutIter> |
| _LIBCPP_HIDE_FROM_ABI constexpr static |
| copy_n_result<_InIter, _OutIter> __go(_InIter __first, _DiffType __n, _OutIter __result) { |
| auto __ret = std::__copy(__first, __first + __n, __result); |
| return {__ret.first, __ret.second}; |
| } |
| |
| template <input_iterator _Ip, weakly_incrementable _Op> |
| requires indirectly_copyable<_Ip, _Op> |
| _LIBCPP_HIDE_FROM_ABI constexpr |
| copy_n_result<_Ip, _Op> operator()(_Ip __first, iter_difference_t<_Ip> __n, _Op __result) const { |
| return __go(std::move(__first), __n, std::move(__result)); |
| } |
| }; |
| } // namespace __copy_n |
| |
| inline namespace __cpo { |
| inline constexpr auto copy_n = __copy_n::__fn{}; |
| } // namespace __cpo |
| } // namespace ranges |
| |
| #endif // _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_INCOMPLETE_RANGES) |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| #endif // _LIBCPP___ALGORITHM_RANGES_COPY_N_H |