[Newbies] Changing superclass doesn't "work automatically"

Randal L. Schwartz merlyn at stonehenge.com
Thu Jul 3 03:27:54 UTC 2008

>>>>> "Marcin" == Marcin Tustin <mm3 at zepler.net> writes:

Marcin> I recently came across a piece of behaviour which is (sort of)
Marcin> understandable, but I wonder if it is how it is supposed to happen or
Marcin> not. I was running through the potsdam seaside tutorial, and I change
Marcin> the superclass of one of the objects from Object to WAComponent, and
Marcin> accepted the change. All the browser tools treated the class as if its
Marcin> protocol included the messages of WAComponent, but running code that
Marcin> sent WAComponent messages signaled MessageNotUnderstood.

Are you sure you weren't dealing with a previous instance of your old class?
I think this kind of a change forks the class def so that new instances have
the new superclass, but old instances still have the old class and old
superclass (anObsoleteYourClassnameHere).

I could be wrong, but tI think that's how it works.

Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095
<merlyn at stonehenge.com> <URL:http://www.stonehenge.com/merlyn/>
Smalltalk/Perl/Unix consulting, Technical writing, Comedy, etc. etc.
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