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

 

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内存管理库

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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) 垃圾回收支持 declare_reachable (C++11)(直到 C++23) undeclare_reachable (C++11)(直到 C++23) declare_no_pointers (C++11)(直到 C++23) undeclare_no_pointers (C++11)(直到 C++23) pointer_safety (C++11)(直到 C++23) get_pointer_safety (C++11)(直到 C++23) 未初始化存储 raw_storage_iterator (直到 C++20*) get_temporary_buffer (直到 C++20*) return_temporary_buffer (直到 C++20*) 显式生命周期管理 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

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

非成员函数

operator==operator!= (直到 C++20)

Deduction guides(C++17)

 

定义于头文件 <scoped_allocator>
pointer allocate( size_type n );	(1)	(since C++11)
pointer allocate( size_type n, const_void_pointer hint );	(2)	(since C++11)

使用外部分配器分配未初始化的存储。

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

2) 另外提供内存局部性提示，通过调用 std::allocator_traits<OuterAlloc>::allocate(outer_allocator(), n, hint)。

参数

n	-	要为其分配存储的对象数量
hint	-	指向附近内存位置的指针

返回值

指向已分配存储的指针。

参见

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