std::make_obj_using_allocator

 

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在标头 <memory> 定义
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 构造函数的实参

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)	准备好与给定类型所要求的使用分配器构造的形式向匹配的实参列表 (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)