Scroll to navigation

std::weak_ptr::reset(3) C++ Standard Libary std::weak_ptr::reset(3)

NAME

std::weak_ptr::reset - std::weak_ptr::reset

Synopsis


void reset() noexcept; (since C++11)


Releases the reference to the managed object. After the call *this manages no
object.

Parameters


(none)

Return value


(none)

Example

// Run this code


#include <iostream>
#include <memory>


int main()
{
auto shared = std::make_shared<int>(), shared2 = shared, shared3 = shared2;


auto weak = std::weak_ptr<int>{shared};


std::cout << std::boolalpha
<< "shared.use_count(): " << shared.use_count() << '\n'
<< "weak.use_count(): " << weak.use_count() << '\n'
<< "weak.expired(): " << weak.expired() << '\n';


weak.reset();


std::cout << "weak.reset();\n"
<< "shared.use_count(): " << shared.use_count() << '\n'
<< "weak.use_count(): " << weak.use_count() << '\n'
<< "weak.expired(): " << weak.expired() << '\n';
}

Output:


shared.use_count(): 3
weak.use_count(): 3
weak.expired(): false
weak.reset();
shared.use_count(): 3
weak.use_count(): 0
weak.expired(): true

See also


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

2024.06.10 http://cppreference.com