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

 

C++

语言

标准库头文件

自立与有宿主实现

具名要求

语言支持库

概念库 (C++20)

诊断库

工具库

字符串库

容器库

迭代器库

范围库 (C++20)

算法库

数值库

输入/输出库

本地化库

正则表达式库 (C++11)

原子操作库 (C++11)

线程支持库 (C++11)

文件系统库 (C++17)

技术规范

 

动态内存管理

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) enable_shared_from_this (C++11) bad_weak_ptr (C++11) default_delete (C++11) 分配器 allocator allocator_traits (C++11) allocator_arg_t (C++11) 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)

未初始化存储 uninitialized_copy uninitialized_fill uninitialized_move (C++17) uninitialized_default_construct (C++17) uninitialized_value_construct (C++17) destroy (C++17) 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) destroy_at (C++17) raw_storage_iterator (C++20 前) get_temporary_buffer (C++20 前) return_temporary_buffer (C++20 前) 垃圾收集支持 declare_reachable (C++11) undeclare_reachable (C++11) declare_no_pointers (C++11) undeclare_no_pointers (C++11) pointer_safety (C++11) get_pointer_safety (C++11) 杂项 pointer_traits (C++11) to_address (C++20) addressof (C++11) align (C++11) assume_aligned (C++20) C 库 malloc aligned_alloc (C++17) calloc realloc free 低层内存管理

 

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!=

推导指引(C++17)

 

定义于头文件 <scoped_allocator>
scoped_allocator_adaptor();	(1)	(C++11 起)
template< class OuterA2 > scoped_allocator_adaptor( OuterA2&& outerAlloc, const InnerAllocs&... innerAllocs) noexcept;	(2)	(C++11 起)
scoped_allocator_adaptor( const scoped_allocator_adaptor& other ) noexcept;	(3)	(C++11 起)
scoped_allocator_adaptor( scoped_allocator_adaptor&& other ) noexcept;	(4)	(C++11 起)
template< class OuterA2 > scoped_allocator_adaptor( const scoped_allocator_adaptor<OuterA2, InnerAllocs...>& other )  noexcept;	(5)	(C++11 起)
template< class OuterA2 > scoped_allocator_adaptor( scoped_allocator_adaptor<OuterA2, InnerAllocs...>&& other ) noexcept;	(6)	(C++11 起)

1) 默认构造函数：值初始化 OuterAlloc 基类及内层分配器成员对象，若为实现所使用。

2) 从 std::forward<OuterA2>(outerAlloc) 构造基类 OuterAlloc ，并用 innerAllocs... 构造内层分配器。此重载仅若 std::is_constructible<OuterAlloc, OuterA2>::value 为 true才参与重载决议。

3) 复制构造函数：从 other 的对应分配器初始化每个分配器

4) 移动构造函数：从 other 的对应分配器移动每个分配器到 *this 内

5) 从 other 的对应分配器初始化每个分配器。此重载仅若 std::is_constructible<OuterAlloc, const OuterA2&>::value 为 true 才参与重载决议。

6) 用移动语义，从 other 的对应分配器初始化每个分配器。此重载仅若 std::is_constructible<OuterAlloc, OuterA2>::value 为 true 才参与重载决议。

参数

outerAlloc	-	外层分配器的构造函数参数
innerAllocs...	-	内层分配其的构造函数参数
other	-	另一 std::scoped_allocator_adaptor

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。

DR	应用于	出版时的行为	正确行为
LWG 2782	C++11	接收 OuterA2 的构造函数未受制约，干扰到元编程	添加了制约

参阅

allocate	用外层分配器分配未初始化存储 (公开成员函数)
construct	在分配的存储上构造一个对象，若适合则传递内存分配器至其构造函数 (公开成员函数)