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// Raw memory manipulators -*- C++ -*- |
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|
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// Copyright (C) 2020-2021 Free Software Foundation, Inc. |
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// |
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// This file is part of the GNU ISO C++ Library. This library is free |
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// software; you can redistribute it and/or modify it under the |
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// terms of the GNU General Public License as published by the |
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// Free Software Foundation; either version 3, or (at your option) |
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// any later version. |
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|
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// This library is distributed in the hope that it will be useful, |
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// but WITHOUT ANY WARRANTY; without even the implied warranty of |
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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// GNU General Public License for more details. |
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|
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// Under Section 7 of GPL version 3, you are granted additional |
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// permissions described in the GCC Runtime Library Exception, version |
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// 3.1, as published by the Free Software Foundation. |
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|
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// You should have received a copy of the GNU General Public License and |
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// a copy of the GCC Runtime Library Exception along with this program; |
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// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
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// <http://www.gnu.org/licenses/>. |
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|
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/** @file bits/ranges_uninitialized.h |
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* This is an internal header file, included by other library headers. |
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* Do not attempt to use it directly. @headername{memory} |
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*/ |
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|
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#ifndef _RANGES_UNINITIALIZED_H |
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#define _RANGES_UNINITIALIZED_H 1 |
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|
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#if __cplusplus > 201703L |
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#if __cpp_lib_concepts |
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|
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#include <bits/ranges_algobase.h> |
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|
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namespace std _GLIBCXX_VISIBILITY(default) |
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{ |
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_GLIBCXX_BEGIN_NAMESPACE_VERSION |
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namespace ranges |
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{ |
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namespace __detail |
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{ |
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template<typename _Tp> |
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constexpr void* |
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__voidify(_Tp& __obj) noexcept |
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{ |
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return const_cast<void*> |
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(static_cast<const volatile void*>(std::__addressof(__obj))); |
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} |
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|
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template<typename _Iter> |
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concept __nothrow_input_iterator |
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= (input_iterator<_Iter> |
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&& is_lvalue_reference_v<iter_reference_t<_Iter>> |
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&& same_as<remove_cvref_t<iter_reference_t<_Iter>>, |
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iter_value_t<_Iter>>); |
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|
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template<typename _Sent, typename _Iter> |
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concept __nothrow_sentinel = sentinel_for<_Sent, _Iter>; |
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|
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template<typename _Range> |
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concept __nothrow_input_range |
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= (range<_Range> |
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&& __nothrow_input_iterator<iterator_t<_Range>> |
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&& __nothrow_sentinel<sentinel_t<_Range>, iterator_t<_Range>>); |
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|
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template<typename _Iter> |
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concept __nothrow_forward_iterator |
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= (__nothrow_input_iterator<_Iter> |
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&& forward_iterator<_Iter> |
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&& __nothrow_sentinel<_Iter, _Iter>); |
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|
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template<typename _Range> |
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concept __nothrow_forward_range |
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= (__nothrow_input_range<_Range> |
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&& __nothrow_forward_iterator<iterator_t<_Range>>); |
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} // namespace __detail |
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|
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struct __destroy_fn |
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{ |
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template<__detail::__nothrow_input_iterator _Iter, |
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__detail::__nothrow_sentinel<_Iter> _Sent> |
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requires destructible<iter_value_t<_Iter>> |
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constexpr _Iter |
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operator()(_Iter __first, _Sent __last) const noexcept; |
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|
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template<__detail::__nothrow_input_range _Range> |
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requires destructible<range_value_t<_Range>> |
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constexpr borrowed_iterator_t<_Range> |
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operator()(_Range&& __r) const noexcept; |
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}; |
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|
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inline constexpr __destroy_fn destroy{}; |
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|
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namespace __detail |
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{ |
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template<typename _Iter> |
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requires destructible<iter_value_t<_Iter>> |
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struct _DestroyGuard |
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{ |
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private: |
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_Iter _M_first; |
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const _Iter* _M_cur; |
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|
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public: |
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explicit |
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_DestroyGuard(const _Iter* __iter) |
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: _M_first(*__iter), _M_cur(__iter) |
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{ } |
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|
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void |
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release() noexcept |
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{ _M_cur = nullptr; } |
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|
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~_DestroyGuard() |
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{ |
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if (_M_cur != nullptr) |
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ranges::destroy(std::move(_M_first), *_M_cur); |
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} |
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}; |
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|
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template<typename _Iter> |
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requires destructible<iter_value_t<_Iter>> |
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&& is_trivially_destructible_v<iter_value_t<_Iter>> |
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struct _DestroyGuard<_Iter> |
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{ |
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explicit |
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_DestroyGuard(const _Iter*) |
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{ } |
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|
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void |
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release() noexcept |
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{ } |
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}; |
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} // namespace __detail |
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|
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struct __uninitialized_default_construct_fn |
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{ |
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template<__detail::__nothrow_forward_iterator _Iter, |
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__detail::__nothrow_sentinel<_Iter> _Sent> |
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requires default_initializable<iter_value_t<_Iter>> |
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_Iter |
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operator()(_Iter __first, _Sent __last) const |
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{ |
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using _ValueType = remove_reference_t<iter_reference_t<_Iter>>; |
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if constexpr (is_trivially_default_constructible_v<_ValueType>) |
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return ranges::next(__first, __last); |
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else |
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{ |
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auto __guard = __detail::_DestroyGuard(&__first); |
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for (; __first != __last; ++__first) |
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::new (__detail::__voidify(*__first)) _ValueType; |
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__guard.release(); |
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return __first; |
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} |
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} |
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|
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template<__detail::__nothrow_forward_range _Range> |
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requires default_initializable<range_value_t<_Range>> |
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borrowed_iterator_t<_Range> |
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operator()(_Range&& __r) const |
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{ |
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return (*this)(ranges::begin(__r), ranges::end(__r)); |
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} |
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}; |
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|
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inline constexpr __uninitialized_default_construct_fn |
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uninitialized_default_construct{}; |
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|
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struct __uninitialized_default_construct_n_fn |
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{ |
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template<__detail::__nothrow_forward_iterator _Iter> |
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requires default_initializable<iter_value_t<_Iter>> |
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_Iter |
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operator()(_Iter __first, iter_difference_t<_Iter> __n) const |
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{ |
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using _ValueType = remove_reference_t<iter_reference_t<_Iter>>; |
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if constexpr (is_trivially_default_constructible_v<_ValueType>) |
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return ranges::next(__first, __n); |
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else |
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{ |
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auto __guard = __detail::_DestroyGuard(&__first); |
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for (; __n > 0; ++__first, (void) --__n) |
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::new (__detail::__voidify(*__first)) _ValueType; |
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__guard.release(); |
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return __first; |
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} |
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} |
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}; |
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|
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inline constexpr __uninitialized_default_construct_n_fn |
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uninitialized_default_construct_n; |
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|
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struct __uninitialized_value_construct_fn |
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{ |
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template<__detail::__nothrow_forward_iterator _Iter, |
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__detail::__nothrow_sentinel<_Iter> _Sent> |
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requires default_initializable<iter_value_t<_Iter>> |
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_Iter |
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operator()(_Iter __first, _Sent __last) const |
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{ |
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using _ValueType = remove_reference_t<iter_reference_t<_Iter>>; |
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if constexpr (is_trivial_v<_ValueType> |
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&& is_copy_assignable_v<_ValueType>) |
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return ranges::fill(__first, __last, _ValueType()); |
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else |
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{ |
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auto __guard = __detail::_DestroyGuard(&__first); |
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for (; __first != __last; ++__first) |
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::new (__detail::__voidify(*__first)) _ValueType(); |
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__guard.release(); |
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return __first; |
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} |
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} |
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|
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template<__detail::__nothrow_forward_range _Range> |
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requires default_initializable<range_value_t<_Range>> |
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borrowed_iterator_t<_Range> |
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operator()(_Range&& __r) const |
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{ |
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return (*this)(ranges::begin(__r), ranges::end(__r)); |
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} |
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}; |
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|
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inline constexpr __uninitialized_value_construct_fn |
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uninitialized_value_construct{}; |
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|
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struct __uninitialized_value_construct_n_fn |
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{ |
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template<__detail::__nothrow_forward_iterator _Iter> |
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requires default_initializable<iter_value_t<_Iter>> |
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_Iter |
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operator()(_Iter __first, iter_difference_t<_Iter> __n) const |
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{ |
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using _ValueType = remove_reference_t<iter_reference_t<_Iter>>; |
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if constexpr (is_trivial_v<_ValueType> |
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&& is_copy_assignable_v<_ValueType>) |
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return ranges::fill_n(__first, __n, _ValueType()); |
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else |
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{ |
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auto __guard = __detail::_DestroyGuard(&__first); |
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for (; __n > 0; ++__first, (void) --__n) |
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::new (__detail::__voidify(*__first)) _ValueType(); |
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__guard.release(); |
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return __first; |
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} |
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} |
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}; |
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|
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inline constexpr __uninitialized_value_construct_n_fn |
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uninitialized_value_construct_n; |
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|
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template<typename _Iter, typename _Out> |
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using uninitialized_copy_result = in_out_result<_Iter, _Out>; |
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|
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struct __uninitialized_copy_fn |
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{ |
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template<input_iterator _Iter, sentinel_for<_Iter> _ISent, |
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__detail::__nothrow_forward_iterator _Out, |
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__detail::__nothrow_sentinel<_Out> _OSent> |
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requires constructible_from<iter_value_t<_Out>, iter_reference_t<_Iter>> |
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uninitialized_copy_result<_Iter, _Out> |
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operator()(_Iter __ifirst, _ISent __ilast, |
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_Out __ofirst, _OSent __olast) const |
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{ |
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using _OutType = remove_reference_t<iter_reference_t<_Out>>; |
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if constexpr (sized_sentinel_for<_ISent, _Iter> |
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&& sized_sentinel_for<_OSent, _Out> |
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&& is_trivial_v<_OutType> |
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&& is_nothrow_assignable_v<_OutType&, |
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iter_reference_t<_Iter>>) |
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{ |
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auto __d1 = __ilast - __ifirst; |
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auto __d2 = __olast - __ofirst; |
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return ranges::copy_n(std::move(__ifirst), std::min(__d1, __d2), |
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__ofirst); |
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} |
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else |
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{ |
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auto __guard = __detail::_DestroyGuard(&__ofirst); |
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for (; __ifirst != __ilast && __ofirst != __olast; |
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++__ofirst, (void)++__ifirst) |
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::new (__detail::__voidify(*__ofirst)) _OutType(*__ifirst); |
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__guard.release(); |
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return {std::move(__ifirst), __ofirst}; |
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} |
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} |
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|
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template<input_range _IRange, __detail::__nothrow_forward_range _ORange> |
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requires constructible_from<range_value_t<_ORange>, |
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range_reference_t<_IRange>> |
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uninitialized_copy_result<borrowed_iterator_t<_IRange>, |
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borrowed_iterator_t<_ORange>> |
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operator()(_IRange&& __inr, _ORange&& __outr) const |
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{ |
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return (*this)(ranges::begin(__inr), ranges::end(__inr), |
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ranges::begin(__outr), ranges::end(__outr)); |
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} |
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}; |
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|
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inline constexpr __uninitialized_copy_fn uninitialized_copy{}; |
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|
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template<typename _Iter, typename _Out> |
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using uninitialized_copy_n_result = in_out_result<_Iter, _Out>; |
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|
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struct __uninitialized_copy_n_fn |
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{ |
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template<input_iterator _Iter, __detail::__nothrow_forward_iterator _Out, |
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__detail::__nothrow_sentinel<_Out> _Sent> |
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requires constructible_from<iter_value_t<_Out>, iter_reference_t<_Iter>> |
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uninitialized_copy_n_result<_Iter, _Out> |
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operator()(_Iter __ifirst, iter_difference_t<_Iter> __n, |
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_Out __ofirst, _Sent __olast) const |
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{ |
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using _OutType = remove_reference_t<iter_reference_t<_Out>>; |
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if constexpr (sized_sentinel_for<_Sent, _Out> |
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&& is_trivial_v<_OutType> |
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&& is_nothrow_assignable_v<_OutType&, |
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iter_reference_t<_Iter>>) |
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{ |
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auto __d = __olast - __ofirst; |
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return ranges::copy_n(std::move(__ifirst), std::min(__n, __d), |
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__ofirst); |
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} |
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else |
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{ |
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auto __guard = __detail::_DestroyGuard(&__ofirst); |
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for (; __n > 0 && __ofirst != __olast; |
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++__ofirst, (void)++__ifirst, (void)--__n) |
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::new (__detail::__voidify(*__ofirst)) _OutType(*__ifirst); |
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__guard.release(); |
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return {std::move(__ifirst), __ofirst}; |
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} |
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} |
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}; |
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|
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inline constexpr __uninitialized_copy_n_fn uninitialized_copy_n{}; |
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|
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template<typename _Iter, typename _Out> |
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using uninitialized_move_result = in_out_result<_Iter, _Out>; |
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|
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struct __uninitialized_move_fn |
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{ |
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template<input_iterator _Iter, sentinel_for<_Iter> _ISent, |
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__detail::__nothrow_forward_iterator _Out, |
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__detail::__nothrow_sentinel<_Out> _OSent> |
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requires constructible_from<iter_value_t<_Out>, |
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iter_rvalue_reference_t<_Iter>> |
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uninitialized_move_result<_Iter, _Out> |
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operator()(_Iter __ifirst, _ISent __ilast, |
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_Out __ofirst, _OSent __olast) const |
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{ |
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using _OutType = remove_reference_t<iter_reference_t<_Out>>; |
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if constexpr (sized_sentinel_for<_ISent, _Iter> |
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&& sized_sentinel_for<_OSent, _Out> |
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&& is_trivial_v<_OutType> |
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&& is_nothrow_assignable_v<_OutType&, |
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iter_rvalue_reference_t<_Iter>>) |
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{ |
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auto __d1 = __ilast - __ifirst; |
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auto __d2 = __olast - __ofirst; |
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auto [__in, __out] |
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= ranges::copy_n(std::make_move_iterator(std::move(__ifirst)), |
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std::min(__d1, __d2), __ofirst); |
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return {std::move(__in).base(), __out}; |
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} |
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else |
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{ |
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auto __guard = __detail::_DestroyGuard(&__ofirst); |
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for (; __ifirst != __ilast && __ofirst != __olast; |
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++__ofirst, (void)++__ifirst) |
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::new (__detail::__voidify(*__ofirst)) |
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_OutType(ranges::iter_move(__ifirst)); |
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__guard.release(); |
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return {std::move(__ifirst), __ofirst}; |
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} |
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} |
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|
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template<input_range _IRange, __detail::__nothrow_forward_range _ORange> |
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requires constructible_from<range_value_t<_ORange>, |
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range_rvalue_reference_t<_IRange>> |
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uninitialized_move_result<borrowed_iterator_t<_IRange>, |
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borrowed_iterator_t<_ORange>> |
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operator()(_IRange&& __inr, _ORange&& __outr) const |
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{ |
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return (*this)(ranges::begin(__inr), ranges::end(__inr), |
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ranges::begin(__outr), ranges::end(__outr)); |
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} |
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}; |
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|
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inline constexpr __uninitialized_move_fn uninitialized_move{}; |
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|
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template<typename _Iter, typename _Out> |
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using uninitialized_move_n_result = in_out_result<_Iter, _Out>; |
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|
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struct __uninitialized_move_n_fn |
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{ |
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template<input_iterator _Iter, __detail::__nothrow_forward_iterator _Out, |
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__detail::__nothrow_sentinel<_Out> _Sent> |
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requires constructible_from<iter_value_t<_Out>, |
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iter_rvalue_reference_t<_Iter>> |
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uninitialized_move_n_result<_Iter, _Out> |
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operator()(_Iter __ifirst, iter_difference_t<_Iter> __n, |
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_Out __ofirst, _Sent __olast) const |
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{ |
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using _OutType = remove_reference_t<iter_reference_t<_Out>>; |
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if constexpr (sized_sentinel_for<_Sent, _Out> |
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&& is_trivial_v<_OutType> |
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&& is_nothrow_assignable_v<_OutType&, |
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iter_rvalue_reference_t<_Iter>>) |
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{ |
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auto __d = __olast - __ofirst; |
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auto [__in, __out] |
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= ranges::copy_n(std::make_move_iterator(std::move(__ifirst)), |
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std::min(__n, __d), __ofirst); |
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return {std::move(__in).base(), __out}; |
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} |
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else |
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{ |
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auto __guard = __detail::_DestroyGuard(&__ofirst); |
| 423 |
for (; __n > 0 && __ofirst != __olast; |
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++__ofirst, (void)++__ifirst, (void)--__n) |
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::new (__detail::__voidify(*__ofirst)) |
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_OutType(ranges::iter_move(__ifirst)); |
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__guard.release(); |
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return {std::move(__ifirst), __ofirst}; |
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} |
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} |
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}; |
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|
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inline constexpr __uninitialized_move_n_fn uninitialized_move_n{}; |
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|
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struct __uninitialized_fill_fn |
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{ |
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template<__detail::__nothrow_forward_iterator _Iter, |
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__detail::__nothrow_sentinel<_Iter> _Sent, typename _Tp> |
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requires constructible_from<iter_value_t<_Iter>, const _Tp&> |
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_Iter |
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operator()(_Iter __first, _Sent __last, const _Tp& __x) const |
| 442 |
{ |
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using _ValueType = remove_reference_t<iter_reference_t<_Iter>>; |
| 444 |
if constexpr (is_trivial_v<_ValueType> |
| 445 |
&& is_nothrow_assignable_v<_ValueType&, const _Tp&>) |
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return ranges::fill(__first, __last, __x); |
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else |
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{ |
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auto __guard = __detail::_DestroyGuard(&__first); |
| 450 |
for (; __first != __last; ++__first) |
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::new (__detail::__voidify(*__first)) _ValueType(__x); |
| 452 |
__guard.release(); |
| 453 |
return __first; |
| 454 |
} |
| 455 |
} |
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|
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template<__detail::__nothrow_forward_range _Range, typename _Tp> |
| 458 |
requires constructible_from<range_value_t<_Range>, const _Tp&> |
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borrowed_iterator_t<_Range> |
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operator()(_Range&& __r, const _Tp& __x) const |
| 461 |
{ |
| 462 |
return (*this)(ranges::begin(__r), ranges::end(__r), __x); |
| 463 |
} |
| 464 |
}; |
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|
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inline constexpr __uninitialized_fill_fn uninitialized_fill{}; |
| 467 |
|
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struct __uninitialized_fill_n_fn |
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{ |
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template<__detail::__nothrow_forward_iterator _Iter, typename _Tp> |
| 471 |
requires constructible_from<iter_value_t<_Iter>, const _Tp&> |
| 472 |
_Iter |
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operator()(_Iter __first, iter_difference_t<_Iter> __n, |
| 474 |
const _Tp& __x) const |
| 475 |
{ |
| 476 |
using _ValueType = remove_reference_t<iter_reference_t<_Iter>>; |
| 477 |
if constexpr (is_trivial_v<_ValueType> |
| 478 |
&& is_nothrow_assignable_v<_ValueType&, const _Tp&>) |
| 479 |
return ranges::fill_n(__first, __n, __x); |
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else |
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{ |
| 482 |
auto __guard = __detail::_DestroyGuard(&__first); |
| 483 |
for (; __n > 0; ++__first, (void)--__n) |
| 484 |
::new (__detail::__voidify(*__first)) _ValueType(__x); |
| 485 |
__guard.release(); |
| 486 |
return __first; |
| 487 |
} |
| 488 |
} |
| 489 |
}; |
| 490 |
|
| 491 |
inline constexpr __uninitialized_fill_n_fn uninitialized_fill_n{}; |
| 492 |
|
| 493 |
struct __construct_at_fn |
| 494 |
{ |
| 495 |
template<typename _Tp, typename... _Args> |
| 496 |
requires requires { |
| 497 |
::new (std::declval<void*>()) _Tp(std::declval<_Args>()...); |
| 498 |
} |
| 499 |
constexpr _Tp* |
| 500 |
operator()(_Tp* __location, _Args&&... __args) const |
| 501 |
noexcept(noexcept(std::construct_at(__location, |
| 502 |
std::forward<_Args>(__args)...))) |
| 503 |
{ |
| 504 |
return std::construct_at(__location, |
| 505 |
std::forward<_Args>(__args)...); |
| 506 |
} |
| 507 |
}; |
| 508 |
|
| 509 |
inline constexpr __construct_at_fn construct_at{}; |
| 510 |
|
| 511 |
struct __destroy_at_fn |
| 512 |
{ |
| 513 |
template<destructible _Tp> |
| 514 |
constexpr void |
| 515 |
operator()(_Tp* __location) const noexcept |
| 516 |
{ |
| 517 |
if constexpr (is_array_v<_Tp>) |
| 518 |
ranges::destroy(ranges::begin(*__location), ranges::end(*__location)); |
| 519 |
else |
| 520 |
__location->~_Tp(); |
| 521 |
} |
| 522 |
}; |
| 523 |
|
| 524 |
inline constexpr __destroy_at_fn destroy_at{}; |
| 525 |
|
| 526 |
template<__detail::__nothrow_input_iterator _Iter, |
| 527 |
__detail::__nothrow_sentinel<_Iter> _Sent> |
| 528 |
requires destructible<iter_value_t<_Iter>> |
| 529 |
constexpr _Iter |
| 530 |
__destroy_fn::operator()(_Iter __first, _Sent __last) const noexcept |
| 531 |
{ |
| 532 |
if constexpr (is_trivially_destructible_v<iter_value_t<_Iter>>) |
| 533 |
return ranges::next(std::move(__first), __last); |
| 534 |
else |
| 535 |
{ |
| 536 |
for (; __first != __last; ++__first) |
| 537 |
ranges::destroy_at(std::__addressof(*__first)); |
| 538 |
return __first; |
| 539 |
} |
| 540 |
} |
| 541 |
|
| 542 |
template<__detail::__nothrow_input_range _Range> |
| 543 |
requires destructible<range_value_t<_Range>> |
| 544 |
constexpr borrowed_iterator_t<_Range> |
| 545 |
__destroy_fn::operator()(_Range&& __r) const noexcept |
| 546 |
{ |
| 547 |
return (*this)(ranges::begin(__r), ranges::end(__r)); |
| 548 |
} |
| 549 |
|
| 550 |
struct __destroy_n_fn |
| 551 |
{ |
| 552 |
template<__detail::__nothrow_input_iterator _Iter> |
| 553 |
requires destructible<iter_value_t<_Iter>> |
| 554 |
constexpr _Iter |
| 555 |
operator()(_Iter __first, iter_difference_t<_Iter> __n) const noexcept |
| 556 |
{ |
| 557 |
if constexpr (is_trivially_destructible_v<iter_value_t<_Iter>>) |
| 558 |
return ranges::next(std::move(__first), __n); |
| 559 |
else |
| 560 |
{ |
| 561 |
for (; __n > 0; ++__first, (void)--__n) |
| 562 |
ranges::destroy_at(std::__addressof(*__first)); |
| 563 |
return __first; |
| 564 |
} |
| 565 |
} |
| 566 |
}; |
| 567 |
|
| 568 |
inline constexpr __destroy_n_fn destroy_n{}; |
| 569 |
} |
| 570 |
_GLIBCXX_END_NAMESPACE_VERSION |
| 571 |
} // namespace std |
| 572 |
#endif // concepts |
| 573 |
#endif // C++20 |
| 574 |
#endif // _RANGES_UNINITIALIZED_H |
