aleaxit at yahoo.com
Mon Sep 4 18:18:44 CEST 2000
"Rainer Deyke" <root at rainerdeyke.com> wrote in message
news:dJBs5.122703$6y5.82311962 at news2.rdc2.tx.home.com...
> "Alex Martelli" <aleaxit at yahoo.com> wrote in message
> news:8ou9i4029q1 at news2.newsguy.com...
> > def allbases(aclass, baselist=):
> > baselist.append(aclass)
> > bases=aclass.__bases__
> > for base in bases:
> > allbases(base, baselist)
> > return baselist
> > def allclasses(aninstance):
> > return allbases(aninstance.__class__)
> This will break the second time allclasses is called. Don't use mutable
> default args unless you really know what you're doing.
Ooops, you're right -- the baselist is never cleared when
a call of allbases from allclasses is finished, but rather
stays around, as 'state' of the allbases function, and
keeps being appended to.
Removing the '=' from the definition of allbases, and
changing the body of allclasses to:
fixes the bug, of course.
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