[Zope-dev] extending objectValues() and objectIds() or ?

[Dennis Nichols]

I have developed a flock of Python products that have attributes 
'first_date', 'last_date', and 'ok_to_publish' with the intention that 
these attributes will be set by the content managers. Each product also has 
an 'isPublishable' method that returns true if 'ok_to_publish' is true 
_and_ today >= 'first_date' _and_ today <= 'last_date'. This all works fine 
but I find myself writing DTML in many places to retrieve a list of objects 
with objectValues() and then looping over them making yet another list of 
only the objects that are publishable.

What I would really like is an objectValues() and an objectIds() that 
return only publishable objects/ids. It looks like this could be easily 
accomplished by {tremble} adding an additional parameter to those two 
routines, say chkPub=None so that I could do a call such as 
objectValues('Poll',1) when I wanted just the publishable Poll items 
returned. However...

1. modifying ObjectManager.py doesn't seem like the best move I've ever 
thought of
2. I'm confused about the ObjectManager internals - can I call my 
isPublishable methods on objects that ObjectManager keeps in its lists? How?

I guess a better question, rather than asking about this one possible 
solution, would be:

How can I extend Zope to give me a list of objects qualified by more than 
just the meta_type?

Guidance gleefully gathered. Thanks!

--
Dennis Nichols
nichols@tradingconnections.com