FEEDBACK WANTED: Type/class unification

Christian Tanzer tanzer at
Thu Aug 2 08:02:26 CEST 2001

> > You mention that the mro-list will be constructed at class definition
> > time. Does that mean that changes to `__bases__` are going to be
> > outlawed? Playing tricks with __bases__ was sometimes handy.
> Changes to __bases__ of built-in types have to be outlawed, but for
> user-defined types it should be possible.  It's not currently
> implemented, but I think it will be.

Uh oh, I didn't think of changing __bases__ for built-ins. That would
be a nightmare waiting to happen. I was just asking about user defined

BTW, you wrote that in 2.2 classes will behave like God <wink>
meant them to behave and that they will be totally unified with types
in a later release. Would that be 2.3? And how would classes change --
besides using the shiny new lookup rule?

> > Do you have a name for the new lookup rule?
> Not yet.  Does it need one?

I think so. It's hard talking about (and teaching) it otherwise. And
`new lookup rule` will age quickly.

Did you invent this rule for yourself or did you steal it from another

Christian Tanzer                                         tanzer at
Glasauergasse 32                                       Tel: +43 1 876 62 36
A-1130 Vienna, Austria                                 Fax: +43 1 877 66 92

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