[Python-Dev] Python-dev Summary for 2002-09-16 to 2002-09-30

[Guido van Rossum]

> > =================================================
> > `builtins instance have modifiable __class__?`__
> > =================================================
> > __ http://mail.python.org/pipermail/python-dev/2002-September/028978.html
> >
> > Samuele Pedroni asked if being able to directly assigning to __class__ was
> > allowed.  Guido said "In 2.3, it's disallowed".  It is highly discouraged
> > in 2.2.2 but  still doable.
> 
> my question and the limitation refer only to builtin types (int,dict
> ...), for instances of (user-defined) subtypes __class__ will be
> still modifiable.

Yes, setting __class__ for instances of user-defined new-style classes
will be allowed (if the new __class__ value is compatible with the old).

--Guido van Rossum (home page: http://www.python.org/~guido/)