[Zope3-dev] calling objects when evaluating path expressions

[Steve Alexander]

> Note, by the way, that the idea of "implements no interfaces" is both 
> bogus and fragile.  Bogus, in that every object implements *some* 
> interface, it just may not be declared.  And fragile, in that it's 
> susceptible to being changed by changes to a base class, or by external 
> declaration via ZCML.  So some poor user's pages could break when a base 
> class changes, perhaps because product A was upgraded and product B 
> inherited from it.  Then a bunch of pages break for no apparent 
> reason...  and the user thinks, "this Zope thing is mysterious and 
> unstable."  Better to force the fixing of the breakage up front.

That's a good point.

I suppose another option is to define an IAmImplicitlyCallable 
interface, and declare that instance-methods and so forth implement this 
interface.

--
Steve Alexander