[ZODB-Dev] Re: [Zope3-dev] PROPOSAL: ZODB Relationships

[Chris Withers]

Roché Compaan wrote:
> What we have at the moment is a graph and strictly speaking a graph has
> no direction in its edges (maybe you meant directed graph). As far as I
> can see graphs are possible, hierarchies are not. Can't one just use
> containment to represent hierarchies? If one can what other use cases
> are there for directionality in associations?

You can only use containment once ;-)

I can't think of any good examples, but if you wanted to express more than one 
relationship that wasn't direction-agnostic, then you couldn't use containment 
for both of them.

cheers,

Chris

PS: Can we trim the cross-posting a bit? zodb-dev feels like the right place for 
this...