[Zope-dev] Re: Zope3 on Google AppEngine

[Malthe Borch]

David Pratt wrote:
> Hi Malthe. Kapil has confirmed the licensing is ZPL with a version bump 
> to 0.5.2 with a change in the headers, etc. I am anxious to experiment 
> with dobbin since it looks so straight forward and nice. I guess I see 
> traversal and containers as possible issues but will be interested in 
> potential solutions. Trails for grok is one possible solution for 
> traversal but will be curious to see approaches for replacing containers.

You're right on the mark here. We haven't yet experimented with 
traversing, and although it's reasonably trivial to implement it 
naïvely, thought could be put into coming up with a more efficient solution.

Zope's traversing model is attractive, especially since inheritance 
plays such an important role. In a relational database, it's expensive, 
but if extensive traversing can be avoided, perhaps it's still reasonable.

We're trying to put this matter a bit in the background right now, as 
there are other, more important tasks to look at first; but it's 
certainly something we need to decide on.

At any rate, adding container-support to dobbin would be a great start. 
I had the idea of using the ``contains`` pragma from zope.app.publisher 
to spell out containment behavior. I think this fits well with the 
general declarative machinery in Zope.

\malthe