[Zope3-dev] Interface implementation declaration weight (was Re: View lookup changes in Zope 3.2?)

[Gary Poster]

Jeff, fwiw, to sidestep the problem with your current implementation,  
and just try to address some possible solutions, we also replace the  
standard contents view, but we do it generally--for the default  
layer.  There are at least a couple of ways to do that (zcml  
overrides and custom folder instances with their own associated  
views).  Looking that way might get you past what sounds like a  
possible time crunch.

That's not to dissuade you from continuing to explore your current  
avenue: it's just offered as a possible practical way out, maybe  
while you figure out your original approach.

On the other hand, to try to answer what I think was one of your  
recent questions, directlyProvided interfaces are more important for  
a match than interfaces from a class.

 >>> from zope import interface
 >>> class IFoo(interface.Interface):
...     pass
...
 >>> class IBar(IFoo):
...     pass
...
 >>> class IBaz(interface.Interface):
...     pass
...
 >>> class Bar(object):
...     interface.implements(IBar)
...
 >>> bar = Bar()
 >>> interface.directlyProvides(bar, IBaz)
 >>> interface.providedBy(bar).__iro__
(<InterfaceClass __main__.IBaz>, <InterfaceClass __main__.IBar>,  
<InterfaceClass __main__.IFoo>, <InterfaceClass  
zope.interface.Interface>)

I believe that's pertinent. :-)

I'm pretty sure there's a proposal on the wiki somewhere with Jim's  
full lookup algorithm that you want, but the iro for the pertinent  
object(s) usually gets me far enough.

HTH

Gary