std::weak_ptr<T>::owner_hash

 

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std::weak_ptr

Member functions

weak_ptr::weak_ptr

weak_ptr::~weak_ptr

weak_ptr::operator=

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weak_ptr::reset

weak_ptr::swap

Observers

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)

Non-member functions

swap(std::weak_ptr)

Helper classes

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

Deduction guides(C++17)

 

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

Returns an unspecified value such that for any object other where owner_equal(other) is true, owner_hash() == other.owner_hash() is true.

This hashing is used to make shared and weak pointers usable as keys in unordered associative containers, typically through std::owner_hash.

Return value

A value that is identical for any std::shared_ptr or std::weak_ptr object sharing the same ownership.

Notes

Feature-test macro	Value	Std	Feature
__cpp_lib_smart_ptr_owner_equality	202306L	(C++26)	Enabling the use of std::weak_ptr as keys in unordered associative containers

See also

owner_hash (C++26)

provides owner-based hashing for shared and weak pointers (class)