std::scoped_allocator_adaptor<OuterAlloc,InnerAlloc...>::allocate

 

C++

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功能特性测试宏 (C++20)

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符号索引

外部库

 

动态内存管理

未初始化内存算法 uninitialized_copy uninitialized_fill uninitialized_move (C++17) uninitialized_default_construct (C++17) uninitialized_value_construct (C++17) destroy (C++17) destroy_at (C++17) voidify (C++20) uninitialized_copy_n (C++11) uninitialized_fill_n uninitialized_move_n (C++17) uninitialized_default_construct_n (C++17) uninitialized_value_construct_n (C++17) destroy_n (C++17) construct_at (C++20) 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::construct_at (C++20) ranges::destroy (C++20) ranges::destroy_n (C++20) ranges::destroy_at (C++20) ranges::uninitialized_copy_n (C++20) ranges::uninitialized_fill_n (C++20) ranges::uninitialized_move_n (C++20) ranges::uninitialized_default_construct (C++20) ranges::uninitialized_value_construct (C++20) ranges::uninitialized_default_construct_n (C++20)   ranges::uninitialized_value_construct_n (C++20) 分配器 allocator allocator_traits (C++11) allocation_result (C++23) 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) scoped_allocator_adaptor (C++11) pmr::polymorphic_allocator (C++17) 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::null_memory_resource (C++17) pmr::synchronized_pool_resource (C++17) pmr::unsynchronized_pool_resource (C++17)   pmr::monotonic_buffer_resource (C++17) pmr::pool_options (C++17) 垃圾收集支持 declare_reachable (C++11)(C++23 前) undeclare_reachable (C++11)(C++23 前) declare_no_pointers (C++11)(C++23 前) undeclare_no_pointers (C++11)(C++23 前) pointer_safety (C++11)(C++23 前) get_pointer_safety (C++11)(C++23 前) 未初始化存储 raw_storage_iterator (C++20 前*) get_temporary_buffer (C++20 前*) return_temporary_buffer (C++20 前*) 显式生存期管理 start_lifetime_asstart_lifetime_as_array (C++23)(C++23)

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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

非成员函数

operator==operator!= (C++20 前)

推导指引(C++17)

 

在标头 <scoped_allocator> 定义
	(1)
pointer allocate( size_type n );			(C++11 起) (C++20 前)
[[nodiscard]] pointer allocate( size_type n );			(C++20 起)
		(2)
pointer allocate( size_type n, const_void_pointer hint );				(C++11 起) (C++20 前)
[[nodiscard]] pointer allocate( size_type n, const_void_pointer hint );				(C++20 起)

用外层分配器分配未初始化存储。

1) 调用 std::allocator_traits<OuterAlloc>::allocate(outer_allocator(), n)

2) 附带提供内存位置提示，通过调用 std::allocator_traits<OuterAlloc>::allocate(outer_allocator(), n, hint)

参数

n	-	要分配存储的对象数
hint	-	指向临近内存位置的指针

返回值

指向分配存储的指针

参阅

allocate	分配未初始化的存储 (std::allocator<T> 的公开成员函数)
allocate [静态]	用分配器分配未初始化的存储 (std::allocator_traits<Alloc> 的公开静态成员函数)