std::shared_ptr<T>::owner_hash

 

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std::shared_ptr

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shared_ptr::shared_ptr

shared_ptr::~shared_ptr

shared_ptr::operator=

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shared_ptr::reset

shared_ptr::swap

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shared_ptr::get

shared_ptr::operator*shared_ptr::operator->

shared_ptr::operator[] (C++17)

shared_ptr::use_count

shared_ptr::unique (until C++20*)

shared_ptr::operator bool

shared_ptr::owner_before

shared_ptr::owner_hash (C++26)

shared_ptr::owner_equal (C++26)

Non-member functions

swap(std::shared_ptr)

make_sharedmake_shared_for_overwrite (C++20)

allocate_sharedallocate_shared_for_overwrite (C++20)

static_pointer_castdynamic_pointer_castconst_pointer_castreinterpret_pointer_cast (C++17)

get_deleter

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operator<<

atomic_xxx functions (until C++26*)

Helper classes

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

hash<std::shared_ptr>

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::shared_ptr as keys in unordered associative containers

Example

See also

owner_hash (C++26)

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

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