std::weak_ptr<T>::owner_hash

 

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智能指针 unique_ptr (C++11) shared_ptr (C++11) weak_ptr (C++11) auto_ptr (直到 C++17*) owner_less (C++11) owner_less<void> (C++17) owner_hash (C++26) owner_equal (C++26) enable_shared_from_this (C++11) bad_weak_ptr (C++11) default_delete (C++11) out_ptr_t (C++23) inout_ptr_t (C++23) 低级内存 管理 operator new operator new[] operator delete operator delete[] get_new_handler (C++11) set_new_handler launder (C++17) bad_alloc bad_array_new_length (C++11) nothrow_t align_val_t (C++17) destroying_delete_t (C++20) new_handler nothrow 其他 pointer_traits (C++11) to_address (C++20) addressof (C++11) align (C++11) assume_aligned (C++20) C 库 malloc calloc realloc    aligned_alloc (C++17) free

 

std::weak_ptr

成员函数

weak_ptr::weak_ptr

weak_ptr::~weak_ptr

weak_ptr::operator=

修改器

weak_ptr::reset

weak_ptr::swap

观察者

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)

推断指南(C++17)

 

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

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

此哈希用于使共享指针和弱指针能够用作无序关联容器中的键，通常通过std::owner_hash。

返回值

对于任何共享相同的拥有权的std::shared_ptr 或 std::weak_ptr 对象，该值都是相同的。

注释

功能测试 宏	值	Std	功能
__cpp_lib_smart_ptr_owner_equality	202306L	(C++26)	启用在无序关联容器中使用std::weak_ptr 作为键。

另请参阅

owner_hash (C++26)

为共享指针和弱指针提供基于所有权的哈希。 (类)