__cxx03/__algorithm/ranges_copy_if.h

0001 //===----------------------------------------------------------------------===//
0002 //
0003 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
0004 // See https://llvm.org/LICENSE.txt for license information.
0005 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
0006 //
0007 //===----------------------------------------------------------------------===//
0008
0009 #ifndef _LIBCPP___CXX03___ALGORITHM_RANGES_COPY_IF_H
0010 #define _LIBCPP___CXX03___ALGORITHM_RANGES_COPY_IF_H
0011
0012 #include <__cxx03/__algorithm/in_out_result.h>
0013 #include <__cxx03/__config>
0014 #include <__cxx03/__functional/identity.h>
0015 #include <__cxx03/__functional/invoke.h>
0016 #include <__cxx03/__iterator/concepts.h>
0017 #include <__cxx03/__iterator/projected.h>
0018 #include <__cxx03/__ranges/access.h>
0019 #include <__cxx03/__ranges/concepts.h>
0020 #include <__cxx03/__ranges/dangling.h>
0021 #include <__cxx03/__utility/move.h>
0022
0023 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
0024 #  pragma GCC system_header
0025 #endif
0026
0027 _LIBCPP_PUSH_MACROS
0028 #include <__cxx03/__undef_macros>
0029
0030 #if _LIBCPP_STD_VER >= 20
0031
0032 _LIBCPP_BEGIN_NAMESPACE_STD
0033
0034 namespace ranges {
0035
0036 template <class _Ip, class _Op>
0037 using copy_if_result = in_out_result<_Ip, _Op>;
0038
0039 namespace __copy_if {
0040 struct __fn {
0041   template <class _InIter, class _Sent, class _OutIter, class _Proj, class _Pred>
0042   _LIBCPP_HIDE_FROM_ABI static constexpr copy_if_result<_InIter, _OutIter>
0043   __copy_if_impl(_InIter __first, _Sent __last, _OutIter __result, _Pred& __pred, _Proj& __proj) {
0044     for (; __first != __last; ++__first) {
0045       if (std::invoke(__pred, std::invoke(__proj, *__first))) {
0046         *__result = *__first;
0047         ++__result;
0048       }
0049     }
0050     return {std::move(__first), std::move(__result)};
0051   }
0052
0053   template <input_iterator _Iter,
0054             sentinel_for<_Iter> _Sent,
0055             weakly_incrementable _OutIter,
0056             class _Proj = identity,
0057             indirect_unary_predicate<projected<_Iter, _Proj>> _Pred>
0058     requires indirectly_copyable<_Iter, _OutIter>
0059   _LIBCPP_HIDE_FROM_ABI constexpr copy_if_result<_Iter, _OutIter>
0060   operator()(_Iter __first, _Sent __last, _OutIter __result, _Pred __pred, _Proj __proj = {}) const {
0061     return __copy_if_impl(std::move(__first), std::move(__last), std::move(__result), __pred, __proj);
0062   }
0063
0064   template <input_range _Range,
0065             weakly_incrementable _OutIter,
0066             class _Proj = identity,
0067             indirect_unary_predicate<projected<iterator_t<_Range>, _Proj>> _Pred>
0068     requires indirectly_copyable<iterator_t<_Range>, _OutIter>
0069   _LIBCPP_HIDE_FROM_ABI constexpr copy_if_result<borrowed_iterator_t<_Range>, _OutIter>
0070   operator()(_Range&& __r, _OutIter __result, _Pred __pred, _Proj __proj = {}) const {
0071     return __copy_if_impl(ranges::begin(__r), ranges::end(__r), std::move(__result), __pred, __proj);
0072   }
0073 };
0074 } // namespace __copy_if
0075
0076 inline namespace __cpo {
0077 inline constexpr auto copy_if = __copy_if::__fn{};
0078 } // namespace __cpo
0079 } // namespace ranges
0080
0081 _LIBCPP_END_NAMESPACE_STD
0082
0083 #endif // _LIBCPP_STD_VER >= 20
0084
0085 _LIBCPP_POP_MACROS
0086
0087 #endif // _LIBCPP___CXX03___ALGORITHM_RANGES_COPY_IF_H