std::make_obj_using_allocator

 

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定义于头文件 <memory>
template< class T, class Alloc, class... Args > constexpr T make_obj_using_allocator( const Alloc& alloc, Args&&... args );		(C++20 起)

以使用分配器构造的手段创建给定的 T 类型对象。

等价于

return std::make_from_tuple<T>(
    std::uses_allocator_construction_args<T>(alloc, std::forward<Args>(args)...)
);

参数

alloc	-	要使用的分配器。
args	-	传递给 T 构造函数的参数

返回值

新创建的 T 类型对象。

异常

可能抛出 T 的构造函数所抛的任何异常，常包括 std::bad_alloc 。

参阅

uses_allocator_construction_args (C++20)	准备匹配给定类型所要求的使用分配器构造的口味的参数列表 (函数模板)
uninitialized_construct_using_allocator (C++20)	以使用分配器构造的手段在指定的内存位置创建给定类型的对象 (函数模板)