[Zope3-dev] Getting the parent object

[Stephan Richter]

At 04:46 PM 3/30/2002 +0000, Chris Withers wrote:
>Stephan Richter wrote:
> >
> > Unless there is a way to get back to the parent otherwise, I propose that
> > we set a __parent__ attribute in an object, when it is added to the
> > container. Therefore, all containers are required to implement that 
> feature.
>
>Circular references.... yum ;-)

Well, it would be simply a double linked list, a very common data type.

>Well, I don't have a problem with a child needing to know it's parent. Whether
>or not this should be stroed in yet another __something__ variable on the 
>child
>is another matter...

Sure.

>How about a much more generic Relationship service which could store this
>information?

This would be too tedious to keep up with.

>Seems that would be much more Zope 3 like in that it doesn't impose 
>restrictions
>on the classes implementing thre __parent__ thing. It also makes relationships
>much mroe dynamic and allows easily things like multiple parents and 
>children...
>
>how does that sound?

But the registry would be HUGE. Then you end up doing exactely what the 
ZODB tries to avoid; you centralize the info and make this center point the 
bottle neck for everything.

>PS: Could the ObjectHub be extended to cover this or is it mroe appropriate to
>get a new service completely?

ObjectHub could be used for that/

But, see Steve's mail. I did not know Wrappers were guaranteed after 
traversal. So that is the solution then. Now wrappers seem a million times 
cooler than before.

Regards,
Stephan

--
Stephan Richter
CBU - Physics and Chemistry Student
Web2k - Web Design/Development & Technical Project Management