Not every class is subclassable (although it would be nice if they were), knowledgable or otherwise. Some people do odd things like blessing an object into a hard-coded class (so you don't get to decide which class the object ends up in), have some factory-like behavior going on where the object ends up in a particular class, and lots of other things. Lots of code I see doesn't pass the null-subclass test.

If you're doing weird wrapper or adapter things, you really aren't subclassing.

--
brian d foy <brian@stonehenge.com>
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In reply to Re^4: OO in Perl 5: still inadequate by brian_d_foy
in thread OO in Perl 5: still inadequate by Aristotle

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