[Zope3-Users] How to resolve bi-directionally navigable association?

Adam Groszer adamg at fw.hu
Mon Aug 8 11:22:48 EDT 2005

Hello Douglas,

Monday, August 8, 2005, 5:53:54 PM, you wrote:

> Adam:

> You should look at the Zope 3 Developer's Handbook. Maybe this part:

> 13.3  Step III: Writing the interfaces
> http://www.zope.org/Wikis/DevSite/Projects/ComponentArchitecture/Zope3Book/contentobject.html

> could help you. As you can see there:

> # Line 45-49: This interface describes via field constraint which other content
> types can contain a message. Clearly message boards can contain messages, but
> also messages can contain other messages - known as responses. We usually
> specify this constraint on the parent on the main content type interface (i.e.
> IMessage) directly, but since this constraint refers explicitely to IMessage we
> have to wait till the interface is defined.
> # Line 52-59: We also want the message to be container, so it can contain
> responses and attachments. However, we do not want any object to be able to be
> added to messages, so we add a precondition as we did for the IMessageBoard
> interface. Again, we have to do this in a separate interface here, since we
> reference IMessage in the condition.

> Hope this helps.

> Regards, Douglas.

> ____________________________________________________
> Start your day with Yahoo! - make it your home page 
> http://www.yahoo.com/r/hs 

Sorry, this is not really my problem:
The book speaks about a containment association.
My problem is a "simple" bi-directional association, which I cannot
break up into a contained and container class.

Best regards,
 Adam                            mailto:adamg at fw.hu

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