On Jan 3, 9:15 pm, "[EMAIL PROTECTED]" <[EMAIL PROTECTED]> wrote: > I have a class that derives from Exception. In Python 2.4, > isinstance(MyClass(), types.InstanceType) was True. In 2.5, it's > False. > > Further experimentation showed that derivation from object was the > culprit; new-style objects are not considered "instances" in the above > sense. I wasn't able to figure out a workaround.
IIRC, this is because since 2.5 Exception is a new style class. New style objects are instances of their class, not of InstanceType as was the case with instances of old-style classes. So in your case isinstance(MyClass(), Exception) will return True. > Is there one, or is > the distinction between traditional classes and built-in types only > going to get more and more hazy? I'm not sure what you mean here. -- Arnaud -- http://mail.python.org/mailman/listinfo/python-list
