[Zope] outstanding zclass questions.

[chas]

Thanks for the speedy replies Michel,

>> 2. If you have a product containing several Zclasses within Zclasses,
>>    why must all of the zope permissions for these Zclasses stay in the
>>    root folder of the product ?
>
>I didn't realize that was the behavior.  There may be a reason for it,
>I'll ask Jim.

Cheers.



>> 3. Are there are any caveats against renaming Zclasses ? I renamed a class
>>    and the instances created with it broke (ie. methods failed). That's
SNAFU
>>    with Lotus Notes but I thought that Zope's Zclasses are truly OO and
>>    can handle it.
>
>I belive you can rename them as long as the class id is the same.  did
>the class id change also?  This would break your instances.

No, I just renamed them - but I'll presume that the errors were due to 
mistakes in my system... my site/odb is becoming a real mess with so many
zclasses being created, edited, deleted. 
On this note, is there any equivalent (or need) for Notes' "compact" ?
(I hope not). It's just that my ODB is getting fat/bloated very quickly
and I'm wondering if deleting objects/instances completely frees all the
space associated with them.



>> 5. Zclasses and Zcatalog : once items have been added to a ZCatalog, why
>>    aren't there pulldowns or multiple select boxes under the MetaData Table
>>    and Indexes tabs so that people can choose which properties or objects
>>    are available ?  DC did this so consistently for all other management
>>    screens in Zope that this omission makes me wonder if I'm missing
>> something
>>    here. (It seems that such a feature would ease use and reduce error.)
>
>Because the Catalog assumes no forknowledge about the objects it can
>catalog.  Any attribute of any set of object can be indexed.  There is
>no way for the Catalog to know, in advance, what possible attributes can
>be indexed.

Yes, the catalog can not know in advance what attributes to index.
But we tell it what objects to catalog and so it should be able to
just like the properties for these (in <object>.<property> format perhaps).

Sorry I didn't explain this clearly enough.
1. create a new zcatalog instance
2. click on the 'find items to zcatalog' tab
3. add the classes that are to be cataloged and any filters

now that the classes have been identified, you could list the properties
in pulldowns/selections.

i only mention it because it would :
a) be easier than switching back to zclass definition to check what properties
   are available.  
b) offer confirmation to the user that s/he has indexed/cataloged the correct
   items (and not too many extraneous items).

Anyway, it was just a thought.



>> 6. As per previous email and post : what permissions need to be set in
order
>>    to create a product that has a zclass within a zclass ? Has anyone
got this
>>    working yet (other than Kevin Dangoor who didn't use the standard zope
>>    permissions in KmNews) ?
>
>This would need to be documented.  Even I'm unclear on the details. 
>Isn't this the same as question number 2? ;)

Sort of - it all comes down to "how do we use zope permissions ?".
But question 6 describes a situation that many people will find
themselves in when building products with nested classes. Are 
they broken or is there some secret voodoo mantra that we must 
chant to get it to work ?


>> Thank you very much - sorry for so many questions but I've really been
>> chasing my tail for the past 3 days - and run out of documentation.
>
>Note that Zope 2.0 is the first system to have anything resembling
>ZClasses.  They are sure to evolve over time, like all things.

Yes, I know - I wasn't meaning to complain... just trying to 
justify the long (and repeated) posts to the list. 
I guess that's why it's called the bleeding edge. ;)

chas