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_SAMPLE_H 10 #define _LIBCPP___ALGORITHM_RANGES_SAMPLE_H 11 12 #include <__algorithm/iterator_operations.h> 13 #include <__algorithm/sample.h> 14 #include <__algorithm/uniform_random_bit_generator_adaptor.h> 15 #include <__config> 16 #include <__iterator/concepts.h> 17 #include <__iterator/incrementable_traits.h> 18 #include <__iterator/iterator_traits.h> 19 #include <__random/uniform_random_bit_generator.h> 20 #include <__ranges/access.h> 21 #include <__ranges/concepts.h> 22 #include <__type_traits/remove_reference.h> 23 #include <__utility/forward.h> 24 #include <__utility/move.h> 25 26 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 27 # pragma GCC system_header 28 #endif 29 30 _LIBCPP_PUSH_MACROS 31 #include <__undef_macros> 32 33 #if _LIBCPP_STD_VER >= 20 34 35 _LIBCPP_BEGIN_NAMESPACE_STD 36 37 namespace ranges { 38 struct __sample { 39 template <input_iterator _Iter, sentinel_for<_Iter> _Sent, weakly_incrementable _OutIter, class _Gen> 40 requires(forward_iterator<_Iter> || random_access_iterator<_OutIter>) && indirectly_copyable<_Iter, _OutIter> && 41 uniform_random_bit_generator<remove_reference_t<_Gen>> 42 _LIBCPP_HIDE_FROM_ABI _OutIter 43 operator()(_Iter __first, _Sent __last, _OutIter __out_first, iter_difference_t<_Iter> __n, _Gen&& __gen) const { 44 _ClassicGenAdaptor<_Gen> __adapted_gen(__gen); 45 return std::__sample<_RangeAlgPolicy>( 46 std::move(__first), std::move(__last), std::move(__out_first), __n, __adapted_gen); 47 } 48 49 template <input_range _Range, weakly_incrementable _OutIter, class _Gen> 50 requires(forward_range<_Range> || random_access_iterator<_OutIter>) && 51 indirectly_copyable<iterator_t<_Range>, _OutIter> && uniform_random_bit_generator<remove_reference_t<_Gen>> 52 _LIBCPP_HIDE_FROM_ABI _OutIter 53 operator()(_Range&& __range, _OutIter __out_first, range_difference_t<_Range> __n, _Gen&& __gen) const { 54 return (*this)( 55 ranges::begin(__range), ranges::end(__range), std::move(__out_first), __n, std::forward<_Gen>(__gen)); 56 } 57 }; 58 59 inline namespace __cpo { 60 inline constexpr auto sample = __sample{}; 61 } // namespace __cpo 62 } // namespace ranges 63 64 _LIBCPP_END_NAMESPACE_STD 65 66 #endif // _LIBCPP_STD_VER >= 20 67 68 _LIBCPP_POP_MACROS 69 70 #endif // _LIBCPP___ALGORITHM_RANGES_SAMPLE_H 71