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bad_weak_ptr Class

 

The latest version of this topic can be found at bad_weak_ptr Class.

Reports bad weak_ptr exception.

Syntax

class bad_weak_ptr  
 : public std::exception {  
public:  
    bad_weak_ptr();
const char *what() throw();

 };  

Remarks

The class describes an exception that can be thrown from the shared_ptr Class constructor that takes an argument of type weak_ptr Class. The member function what returns "bad_weak_ptr".

Example

// std_tr1__memory__bad_weak_ptr.cpp   
// compile with: /EHsc   
#include <memory>   
#include <iostream>   
  
int main()   
    {   
    std::weak_ptr<int> wp;   
  
     {   
    std::shared_ptr<int> sp(new int);   
    wp = sp;   
     }   
  
    try   
        {   
        std::shared_ptr<int> sp1(wp); // weak_ptr has expired   
        }   
    catch (const std::bad_weak_ptr&)   
        {   
        std::cout << "bad weak pointer" << std::endl;   
        }   
    catch (...)   
        {   
        std::cout << "unknown exception" << std::endl;   
        }   
  
    return (0);   
    }  
  
bad weak pointer  

Requirements

Header: <memory>

Namespace: std

See Also

weak_ptr Class