[Zope-dev] Pointer or reference object

[Johan Carlsson]

One problem with having a reference count base class that's
responsible for inactivate/delete the reference object is
that Zope lacks a event model. 
If a folder/container is deleted it doesn't inform its 
siblings before it's deleted. And that may lead to invalid
reference objects.
I think ZCatalog have the same problem?

There is a pointer product in the download section, 
have you looked at it? 

//Johan





> I meant to use resolve_url, to find any references to an object upon it's
> deletion.  Changes in an object's state really wouldn't matter if there is
> a way to truely 'mirror' an object.  The name spaces would have to either
> be selectable, or since it is a mirror, then it aquires the name space of
> the object that it is mirroring (and exact mirror).  Like I said, I don't
> have any idea if this 'pointer' is even possible in the ZODB.  Anyone from
> DC thinkning about this?
> 
> All my best,
> 
> Jason
> 
> 
> 
> Johan Carlsson writes:
> 
> > 
> > Yes, I have thought about it.
> > 
> > One solution I thought of is use an object referens counter
> > base class for "referencable objects".
> > The base class should be responsible for manageing references
> > and take action on the references when the objects state changes.
> > 
> > One problem is how to handle acqusition.
> > Should the referenced object be viewed in it's own context or
> > the reference objects context? Or should the contexts merge?
> > 
> > 
> > How did you intend to use ZCataloges for the ZMirror?
> > 
> > 
> > //Johan
> > 
> > 
> > 
> > 
> > > Zopsters,
> > > 
> > > This is very out of the blue, but has anyone thought about 
> tackling the
> > > 'reference' question by using a phantom Zope object?  I don't know
> > > nearly enough Python to answer this question, but maybe someone can.  
> > > 
> > > Is it possible to create a 'Reference' object that really 
> stores the url
> > > of another object and maquerades as the other object's meta_type. 
> > > Anything that is asked of the 'Reference' object, just get's passed
> > > along to the real object in it's place?  Obviously whenever you delete
> > > an object any 'References' with that object's url stored in them get
> > > deleted too(ZCatalog could hold these).  Sort of like a reflective
> > > mirror.  You see the object in the mirror but you aren't actually
> > > looking at the object, you are looking at the mirror.  A ZMirror.
> > > 
> > > All my best,
> > > 
> > > 
> > > -- 
> > > Jason Spisak
> > > 444@hiretechs.com
> > > 
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> 
> 
> Jason Spisak
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