std::scoped_allocator_adaptor<OuterAlloc,InnerAlloc...>::outermost, outermost-construct, outermost-destroy

 

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内存管理库

voidify (仅用于阐述*) 分配器 allocator allocator_traits (C++11) allocation_result (C++23) scoped_allocator_adaptor (C++11) pmr::polymorphic_allocator (C++17) allocator_arg (C++11) uses_allocator (C++11) uses_allocator_construction_args (C++20) make_obj_using_allocator (C++20) uninitialized_construct_using_allocator (C++20) 未初始化内存算法 uninitialized_copy uninitialized_fill uninitialized_move (C++17) uninitialized_copy_n (C++11) uninitialized_fill_n uninitialized_move_n (C++17) construct_at (C++20) uninitialized_default_construct (C++17) uninitialized_value_construct (C++17) destroy (C++17) uninitialized_default_construct_n (C++17) uninitialized_value_construct_n (C++17) destroy_n (C++17) destroy_at (C++17) 受约束的未初始化内存算法 ranges::uninitialized_copy (C++20) ranges::uninitialized_fill (C++20) ranges::uninitialized_move (C++20) ranges::uninitialized_copy_n (C++20)  ranges::uninitialized_fill_n (C++20) ranges::uninitialized_move_n (C++20) ranges::construct_at (C++20) ranges::uninitialized_default_construct (C++20) ranges::uninitialized_value_construct (C++20) ranges::destroy (C++20) ranges::uninitialized_default_construct_n (C++20)  ranges::uninitialized_value_construct_n (C++20) ranges::destroy_n (C++20) ranges::destroy_at (C++20) 内存资源 pmr::memory_resource (C++17) pmr::get_default_resource (C++17) pmr::set_default_resource (C++17) pmr::new_delete_resource (C++17) pmr::pool_options (C++17) pmr::null_memory_resource (C++17) pmr::synchronized_pool_resource (C++17) pmr::unsynchronized_pool_resource (C++17) pmr::monotonic_buffer_resource (C++17) 显式生存期管理 start_lifetime_as (C++23) start_lifetime_as_array (C++23) 用于复合类设计的类型 indirect (C++26) polymorphic (C++26) 未初始化存储 (C++20 前) raw_storage_iterator (C++17 弃用) get_temporary_buffer (C++17 弃用) return_temporary_buffer (C++17 弃用) 垃圾收集器支持 (C++23 前) declare_reachable (C++11)(C++23 前) declare_no_pointers (C++11)(C++23 前) pointer_safety (C++11)(C++23 前) undeclare_reachable (C++11)(C++23 前) undeclare_no_pointers (C++11)(C++23 前) get_pointer_safety (C++11)(C++23 前)

低层内存管理 operator newoperator new[] operator deleteoperator delete[] nothrow_t nothrow new_handler set_new_handler get_new_handler (C++11) bad_alloc bad_array_new_length (C++11) align_val_t (C++17) destroying_delete_t (C++20) launder (C++17) 智能指针 unique_ptr (C++11) shared_ptr (C++11) weak_ptr (C++11) auto_ptr (C++17 前*) owner_less (C++11) owner_less<void> (C++17) owner_hash (C++26) owner_equal (C++26) enable_shared_from_this (C++11) bad_weak_ptr (C++11) default_delete (C++11) out_ptr_t (C++23) inout_ptr_t (C++23) 杂项 pointer_traits (C++11) to_address (C++20) addressof (C++11) align (C++11) assume_aligned (C++20) is_sufficiently_aligned (C++26) C 库 malloc calloc realloc free aligned_alloc (C++17)

 

std::scoped_allocator_adaptor

成员函数

scoped_allocator_adaptor::scoped_allocator_adaptor

scoped_allocator_adaptor::~scoped_allocator_adaptor

scoped_allocator_adaptor::operator=

scoped_allocator_adaptor::inner_allocator

scoped_allocator_adaptor::outer_allocator

scoped_allocator_adaptor::allocate

scoped_allocator_adaptor::deallocate

scoped_allocator_adaptor::max_size

scoped_allocator_adaptor::construct

scoped_allocator_adaptor::destroy

scoped_allocator_adaptor::select_on_container_copy_construction

scoped_allocator_adaptor::outermost scoped_allocator_adaptor::outermost-construct scoped_allocator_adaptor::outermost-destroy

非成员函数

operator==operator!= (C++20 前)

推导指引(C++17)

 

template< class Alloc > /* 未指定 */ /*outermost*/( Alloc&& alloc = *this );	(1)	(仅用于阐述*)
template< class T, class... Args > void /*outermost-construct*/( T* p, Args&&... args );	(2)	(仅用于阐述*)
template< class T > void /*outermost-destroy*/( T* p );	(3)	(仅用于阐述*)

这些仅用于阐述的辅助函数用于成员函数 construct() 和 destroy() 中。

1) 获取 alloc 的最外层分配器。

• 如果表达式 alloc.outer_allocator() 合法，那么就会返回 outermost (alloc.outer_allocator())。
• 否则就会返回 alloc。

2,3) 使用 *this 的最外层分配器构造或销毁对象。

给定类型 std::allocator_traits<std::remove_reference_t<decltype(outermost ())>> 为 outermost_traits：

2) 等价于 outermost_traits::construct(outermost (), p, std::forward<Args>(args)...);。

3) 等价于 outermost_traits::destroy(outermost (), p);。

缺陷报告

下列更改行为的缺陷报告追溯地应用于以前出版的 C++ 标准。

缺陷报告	应用于	出版时的行为	正确行为
LWG 3116	C++11	outermost 的递归条件是 “alloc 拥有成员函数 outer_allocator()”	将条件改为 表达式 alloc.outer_allocator() 合法”

参阅

construct [静态]	在已分配存储中构造对象 (函数模板)
destroy [静态]	析构储存于已分配存储中的对象 (函数模板)