std::weak_ptr::use_count

 

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std::weak_ptr

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weak_ptr::weak_ptr

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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

Non-member functions

std::swap

 

long use_count() const;		(since C++11)

Returns the number of shared_ptr instances that share ownership of the managed object, or ​0​ if the managed object has already been deleted, i.e. *this is empty.

Parameters

(none)

Return value

The number of shared_ptr instances sharing the ownership of the managed object.

Exceptions

noexcept specification:  

noexcept

  (since C++11)

Notes

expired() may be faster than use_count().

See also

expired	checks whether the referenced object was already deleted (public member function)