Debugging possible bug

Boris Gaertner Boris.Gaertner at
Sun Jan 5 19:10:27 UTC 2003

----- Original Message ----- 
From: Niko Schwarz < at>

> JabberXMLReader(ProtoObject)>>doesNotUnderstand:

The instance of  JabberXMLReader inherited the
method  doesNotUnderstand:  from  ProtoObject!
This is very suspicious:
The method  doesNotUnderstand is also implemented
in the instance protocol of  Object, so all subclasses
of  Object that do not redefine this method will inherit it
from there. Inheritance from ProtoObject indicates
that  JabberXMLReader is subclassed not to
Object, but to ProtoObject.

The method  Inspector>>selection  uses a few methods
that all subclasses of Object understand (namely:
longPrintString, class basicAt: instVarAt:) Classes
that do not inherit from Object are difficult to debug
unless they redefine these methods (you can copy 
them from Object. Other mportant methods are
basicSize and basicInspect).
The real question is however: Why is Object not
an appropriate superclass for JabberXMLReader?

Can you please tell me a few words about JabberXMLReader
and why it is subclassed to ProtoObject??

Greetings, Boris

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