[Zope3-dev] Allowing views to be registered for classes rather than interfaces.

[Martijn Faassen]

Jim Fulton wrote:
> >The point about the interface hierarchy is to allow multiple 
> >implementations
> >of the same interface. Are the schemas described here designed with this
> >in mind? Or does one really only ever expect a single implementation?
> 
> Ah, this is important. The point of the separate interface hierarchy was 
> *not* to support multiple implementations.  The point of the separate 
> interface hierarchy was to protect UI designers from needing to dig through 
> the application code.

I thought this was just one point in our conversations. I thought 
it was also a point that multiple packages could implement the
same interface and that these therefore should not be bound to
implementations.

In the archives I can find extensive discussions about the
general reorganization and about view separation, but cannot
find much about the interface separation issue.

> I suspect that we should call BS on this.

After our extensive feedback from UI designers either way, huh? :)

> Tres has argued (with merit) that only interfaces designed to support 
> multiple implementations should go in a separate hierarchy.

Yes, and I'm arguing only those interfaces should be written in the
first place. :) No, I'm not seriously arguing that! Interfaces have
other useful roles. I'm just wondering whether there are not
interfaces whose primary reason for existence is to be CA glue, and
whether there aren't other ways.

Regards,

Martijn