testing if shared_ptr has been assigned

From: TEA Hartmann, Steven (SHartmann_at_[hidden])
Date: 2002-12-11 14:01:55

I need some help in testing for the condition of whether a shared_ptr has
been assigned.  In the following example, the "if( b != NULL ) does not
work. How would I do this test?

typedef boost::shared_ptr<int> IPtr;

int i( 0 );
IPtr a( i );
IPtr b;

if( some condition )
        b = a;

if( b != NULL ) { // How should this really be coded?
}
        

Best Regards,

Steve

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