[Zope-dev] Re: What's the deal with sublocations?

[Philipp von Weitershausen]

Philipp von Weitershausen wrote:
> Stefan H. Holek wrote:
>> Most ObjectEvents are dispatched to "sublocations".
> 
> Well, the ones that deal with the object hierarchy. This mostly concerns 
> IObjectMovedEvents and their sub-event types (added, removed). I don't 
> think it makes a lot of sense to dispatch other object events.
> 
>> I was wondering whether it is ok for me to expect a certain dispatch 
>> order, i.e. top-down (container before sublocation) or bottom-up 
>> (sublocation before container)?
> 
> No. The dispatch to sublocations is an event handler itself. One should 
> not depend on the execution order of event handlers, therefore you 
> should not depend on this dispatch happening before or after your own 
> event handler(s) for IObjectMovedEvent.
> 
>> What I find is that this order depends on things like the exact 
>> interface a handler is registered for and, in Zope 2.9 (+3.2), even on 
>> the way I run tests (!).
>>
>> I can only conclude that there is no guaranteed dispatch order. Now, 
>> should there be? Where can I learn about this contract?
> 
> Again, the contract is "don't expect an order".

I've rejected http://www.zope.org/Collectors/Zope/2308 therefore.