[Python-Dev] Afterthoughts: PEP 252, PEP 253 and jython issues

[Samuele Pedroni]

Yes, I'm thinking furiously.

GvR >  A safe rule would be to require that all Python classes in a
GvR > given inheritance graph should derive from the same C/Java class.  I

> That would mean that all C/Java behaviour is always only at the top
> of the mro, right?
> 
> I had the same idea because this would make my life easier.
> 
> A problem: some of the Zope porters reported that there are classes
> that inherits from more than a single ExtensionClass in Zope :-(
> don't know if that is true. (**)
Oops, this is already a problem with the actual best_base rule,
I don't know if my reinterpretation is OK, but doesn't it 
basically states that all C types subclassed by a new C level class
should be in a  subtyping relationship that means:

with
A isa list isa object
B isa special_list isa list isa object
C isa object

class D(A,B,C): ... is OK

but with

Z isa Cbadboy isa object

then class D(Z,A) isn't allowed.

but if that is already *not* *a* *problem* then I think the rule could
be not that bad ...

regards.