From: Larry Evans (jcampbell3_at_[hidden])
Date: 2002-01-21 09:43:53
Peter Dimov wrote:
> From: "Larry Evans" <jcampbell3_at_[hidden]>
> > Greg Colvin wrote:
> > > From: "Larry Evans" <jcampbell3_at_[hidden]>
> > > > ... Could someone
> > > > describe a case where this is not so, i.e. the user does not know what
> > > > the most derived class is when creating a shared_ptr<T>?
> > >
> > > When using a factory function that returns only a pointer to base?
> > >
> > If you mean using the shared_ptr(T*) CTOR, then this is similar
> > to Maeder's example and, as pointed out in
> > http://groups.yahoo.com/group/boost/message/23341
> > and the user is responsible for avoiding this.
> I suppose Greg meant
> shared_ptr<Base> createObject(std::string classId);
> or something similar.
Yes, I realized that too late.
Now, about counted_base. Since one of the purposes of counted_base is to
overcome the lack of virtual DTOR, could John Maddox's is_polymorphic<>
trait be used to provide a specialized version of counted_base_impl without the
extra D del pointer?
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