Re: Detachable objects in BPL

From: pplumlee_at_[hidden]
Date: 2001-02-09 13:17:47

"David Abrahams" <abrahams_at_m...> wrote:

> > Try this experiment. Take 'example1.cpp' from the (excellent)
Boost Python
> > Library. It's got a class called hello::world or some such. Now
add to it
> > this class:
> >
> > world *getAnotherWorld ()  {  return new world (1);  }
> >
> > Leave aside for a moment the usual fretting about leaky
interfaces, and
> add a
> > 'def' to describe that method:
> >
> > ... world.def (&hello::world::getAnotherWorld, "getAnotherWorld");
> >
> > Now try to compile. The compile bombs deep in the nested templates
that
> are
> > trait-ing out the method pointer
> >
> > Am I missing something? Do I have to pre-wrap that 'world' in an
adapter,
> or
> > do I add a trait for it, or what?
> 
> Just return a std::auto_ptr<world> or a boost::shared_ptr<world>.
You need
> to give Python reason to believe it can take ownership of this
pointer.

How do I do a None? When I pack NULL in that boost::shared_ptr<> the
python croaks with a BPL-generated conversion error.

--Phlip