libcxx/include/__memory/ranges_construct_at.h

   1 // -*- C++ -*-
   2 //===----------------------------------------------------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #ifndef _LIBCPP___MEMORY_RANGES_CONSTRUCT_AT_H
  11 #define _LIBCPP___MEMORY_RANGES_CONSTRUCT_AT_H
  12
  13 #include <__concepts/destructible.h>
  14 #include <__config>
  15 #include <__function_like.h>
  16 #include <__iterator/incrementable_traits.h>
  17 #include <__iterator/readable_traits.h>
  18 #include <__memory/concepts.h>
  19 #include <__memory/construct_at.h>
  20 #include <__ranges/access.h>
  21 #include <__ranges/concepts.h>
  22 #include <__ranges/dangling.h>
  23 #include <__utility/declval.h>
  24 #include <__utility/forward.h>
  25 #include <__utility/move.h>
  26
  27 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  28 #pragma GCC system_header
  29 #endif
  30
  31 _LIBCPP_BEGIN_NAMESPACE_STD
  32
  33 #if !defined(_LIBCPP_HAS_NO_RANGES)
  34 namespace ranges {
  35
  36 // construct_at
  37
  38 namespace __construct_at {
  39
  40 struct __fn final : private __function_like {
  41   _LIBCPP_HIDE_FROM_ABI constexpr explicit __fn(__tag __x) noexcept : __function_like(__x) {}
  42
  43   template<class _Tp, class... _Args, class = decltype(
  44     ::new (declval<void*>()) _Tp(declval<_Args>()...)
  45   )>
  46   _LIBCPP_HIDE_FROM_ABI
  47   constexpr _Tp* operator()(_Tp* __location, _Args&& ...__args) const {
  48     return _VSTD::construct_at(__location, _VSTD::forward<_Args>(__args)...);
  49   }
  50 };
  51
  52 } // namespace __construct_at
  53
  54 inline namespace __cpo {
  55   inline constexpr auto construct_at = __construct_at::__fn(__function_like::__tag());
  56 } // namespace __cpo
  57
  58 // destroy_at
  59
  60 namespace __destroy_at {
  61
  62 struct __fn final : private __function_like {
  63   _LIBCPP_HIDE_FROM_ABI constexpr explicit __fn(__tag __x) noexcept : __function_like(__x) {}
  64
  65   template <destructible _Tp>
  66   _LIBCPP_HIDE_FROM_ABI
  67   constexpr void operator()(_Tp* __location) const noexcept {
  68     _VSTD::destroy_at(__location);
  69   }
  70 };
  71
  72 } // namespace __destroy_at
  73
  74 inline namespace __cpo {
  75   inline constexpr auto destroy_at = __destroy_at::__fn(__function_like::__tag());
  76 } // namespace __cpo
  77
  78 // destroy
  79
  80 namespace __destroy {
  81
  82 struct __fn final : private __function_like {
  83   _LIBCPP_HIDE_FROM_ABI constexpr explicit __fn(__tag __x) noexcept : __function_like(__x) {}
  84
  85   template <__nothrow_input_iterator _InputIterator, __nothrow_sentinel_for<_InputIterator> _Sentinel>
  86     requires destructible<iter_value_t<_InputIterator>>
  87   _LIBCPP_HIDE_FROM_ABI
  88   constexpr _InputIterator operator()(_InputIterator __first, _Sentinel __last) const noexcept {
  89     return _VSTD::__destroy(_VSTD::move(__first), _VSTD::move(__last));
  90   }
  91
  92   template <__nothrow_input_range _InputRange>
  93     requires destructible<range_value_t<_InputRange>>
  94   _LIBCPP_HIDE_FROM_ABI
  95   constexpr borrowed_iterator_t<_InputRange> operator()(_InputRange&& __range) const noexcept {
  96     return (*this)(ranges::begin(__range), ranges::end(__range));
  97   }
  98 };
  99
 100 } // namespace __destroy
 101
 102 inline namespace __cpo {
 103   inline constexpr auto destroy = __destroy::__fn(__function_like::__tag());
 104 } // namespace __cpo
 105
 106 // destroy_n
 107
 108 namespace __destroy_n {
 109
 110 struct __fn final : private __function_like {
 111   _LIBCPP_HIDE_FROM_ABI constexpr explicit __fn(__tag __x) noexcept : __function_like(__x) {}
 112
 113   template <__nothrow_input_iterator _InputIterator>
 114     requires destructible<iter_value_t<_InputIterator>>
 115   _LIBCPP_HIDE_FROM_ABI
 116   constexpr _InputIterator operator()(_InputIterator __first, iter_difference_t<_InputIterator> __n) const noexcept {
 117     return _VSTD::destroy_n(_VSTD::move(__first), __n);
 118   }
 119 };
 120
 121 } // namespace __destroy_n
 122
 123 inline namespace __cpo {
 124   inline constexpr auto destroy_n = __destroy_n::__fn(__function_like::__tag());
 125 } // namespace __cpo
 126
 127 } // namespace ranges
 128 #endif // !defined(_LIBCPP_HAS_NO_RANGES)
 129
 130 _LIBCPP_END_NAMESPACE_STD
 131
 132 #endif // _LIBCPP___MEMORY_RANGES_CONSTRUCT_AT_H