std::pmr::polymorphic_allocator<T>::polymorphic_allocator

 

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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) 垃圾收集器支持 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::pmr::polymorphic_allocator

成员函数

polymorphic_allocator::polymorphic_allocator

polymorphic_allocator::allocate

polymorphic_allocator::deallocate

polymorphic_allocator::construct

polymorphic_allocator::destroy (C++20/26*)

polymorphic_allocator::allocate_bytes (C++20)

polymorphic_allocator::deallocate_bytes (C++20)

polymorphic_allocator::allocate_object (C++20)

polymorphic_allocator::deallocate_object (C++20)

polymorphic_allocator::new_object (C++20)

polymorphic_allocator::delete_object (C++20)

polymorphic_allocator::select_on_container_copy_construction

polymorphic_allocator::resource

非成员函数

operator==operator!= (C++20 前)

 

polymorphic_allocator() noexcept;	(1)
polymorphic_allocator( const polymorphic_allocator& other ) = default;	(2)
template< class U > polymorphic_allocator( const polymorphic_allocator<U>& other ) noexcept;	(3)
polymorphic_allocator( std::pmr::memory_resource* r );	(4)

构造新的 polymorphic_allocator。

1) 以 std::pmr::get_default_resource() 的返回值为底层内存资源构造一个 polymorphic_allocator。

2,3) 以 other.resource() 为底层内存资源构造 polymorphic_allocator。

4) 以 r 为底层内存资源构造 polymorphic_allocator。此构造函数提供从 std::pmr::memory_resource* 的隐式转换。

参数

other	-	要复制的另一 polymorphic_allocator
r	-	指向要使用的内存资源的指针。不可为空。

异常

4) 不抛出任何异常。

注解

复制使用 polymorphic_allocator 的容器不会调用分配器的复制构造函数。新容器会替代地以 select_on_container_copy_construction 的返回值（默认构造的 polymorphic_allocator）为其分配器。

参阅

select_on_container_copy_construction

为容器的复制构造函数的使用创建一个新的 polymorphic_allocator (公开成员函数)