std::bad_weak_ptr

 

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Defined in header <memory>
class bad_weak_ptr;		(since C++11)

std::bad_weak_ptr is the type of the object thrown as exceptions by the constructors of std::shared_ptr that take std::weak_ptr as the argument, when the std::weak_ptr refers to an already deleted object.

Inheritance diagram

Member functions

(constructor)

constructs the bad_weak_ptr object (public member function)

std::bad_weak_ptr ::bad_weak_ptr()

bad_weak_ptr() noexcept;

Constructs a new instance of std::bad_weak_ptr. what() returns an implementation-defined null-terminated byte string.

Parameters

(none)

Inherited from std::exception

Member functions

(destructor) [virtual]	destroys the exception object (virtual public member function of std::exception)
what [virtual]	returns an explanatory string (virtual public member function of std::exception)

Example

Run this code

#include <memory>
#include <iostream>
int main()
{
    std::shared_ptr<int> p1(new int(42));
    std::weak_ptr<int> wp(p1);
    p1.reset();
    try {
        std::shared_ptr<int> p2(wp);
    } catch(const std::bad_weak_ptr& e) {
        std::cout << e.what() << '\n';
    }
}

Output:

std::bad_weak_ptr

See also

shared_ptr (C++11)	smart pointer with shared object ownership semantics (class template)
weak_ptr (C++11)	weak reference to an object managed by std::shared_ptr (class template)