std::weak_ptr<T>::owner_hash

 

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std::weak_ptr

成员函数

weak_ptr::weak_ptr

weak_ptr::~weak_ptr

weak_ptr::operator=

修饰符

weak_ptr::reset

weak_ptr::swap

观察器

weak_ptr::use_count

weak_ptr::expired

weak_ptr::lock

weak_ptr::owner_before

weak_ptr::owner_hash (C++26)

weak_ptr::owner_equal (C++26)

非成员函数

swap(std::weak_ptr)

辅助类

atomic<std::weak_ptr> (C++20)

推导指引(C++17)

 

std::size_t owner_hash() const noexcept;		(since C++26)

返回一个未指定的值，使得对于任何对象 other，其中 owner_equal(other) 为 true，owner_hash() == other.owner_hash() 也为 true。

此哈希用于使 shared 和 weak 指针可用作无序关联容器中的键，通常通过 std::owner_hash。

返回值

对于任何共享相同所有权的 std::shared_ptr 或 std::weak_ptr 对象，此函数返回相同的值。

注解

特性测试 宏	值	Std	特性
__cpp_lib_smart_ptr_owner_equality	202306L	(C++26)	启用 std::weak_ptr 作为 无序关联容器中键的使用

参见

owner_hash (C++26)

为 shared 和 weak 指针提供基于所有者的哈希 (类)