Re: downcasting smart pointers (suggested code)

From: martinschuerch_at_[hidden]
Date: 2001-07-24 04:59:00

Thanks for the feedback
> I sent this hours ago, but it hasn't shown up, so I'll try again.
> 
> This looks like a good start, thanks.
Thanks, a starting point is all it should be. Probably you noted the 
bug with the missing return or else in the member-template.

>  I think do_dynamic_cast is the 
> name we previously agreed on for your shared_dynamic_cast, and that
> we wanted a version that worked for raw pointers as well.  And it 
> would still be good to have a polymorphic_cast for shared_ptr.  
Must 
> doing so really create dependencies?
Sorry, I didn't know that there were already some discussions about 
the names. As long there is a do_dynamic_cast in the smartptr.hpp an 
integration in polymorphic_cast is just perfect for me.

I didn' found the messages with the discussion about a raw-pointer 
version. Can anybody give me the message-id?

Martin

> > Member-template:
> > 
> > template<class Q>
> > void downcasted_copy_to( shared_ptr<Q>& q ) const
> > {
> > Q* rawq = dynamic_cast<Q*>(px);
> > if( !rawq || !px ) { q = shared_ptr<Q>(); }
                                             ^^return ;
> > shared_ptr<Q> ptmp;
> > ptmp.px = rawq;
> > ++*pn;
> > ptmp.pn = pn;
> > q.swap( ptmp );
> > }