std::allocation_result

 

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在标头 <memory> 定义
template< class Pointer > struct allocation_result {     Pointer ptr;     std::size_t count; };		(C++23 起)

allocation_result 特化是适合的分配器 (Allocator) 类型的 allocate_at_least 成员函数（例如 std::allocator::allocate_at_least ）及 std::allocate_at_least 的返回类型。

allocation_result 的每个特化均无基类或 ptr 与 count 之外的声明成员，从而它适合聚合初始化及结构化绑定。

模板形参

Pointer

-

常为 std::allocator_traits<Alloc>::pointer ，其中 Alloc 为分配器 (Allocator) 类型

成员对象

ptr (C++23)	常用于 allocate_at_least 所分配的存储中首元素的地址 (公开成员对象)
count (C++23)	常用于 allocate_at_least 所分配的存储中的实际元素数 (公开成员对象)

参阅

allocate_at_least (C++23)	分配与请求的大小至少一样大的未初始化存储 (std::allocator<T> 的公开成员函数)
allocate_at_least (C++23)	经由分配器分配至少与请求的大小一样大的存储 (函数模板)