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std::weak_ptr<T>::reset

Since C++11
void reset() noexcept;

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

Parameters

(none)

Return value

(none)

Example

#include <memory>
#include <iostream>

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

std::weak_ptr<T>::reset

Since C++11
void reset() noexcept;

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

Parameters

(none)

Return value

(none)

Example

#include <memory>
#include <iostream>

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