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Date: Wed, 19 Nov 2014 13:14:59 -0600
Subject: Potential pitfalls when going from old-style to new-style classes
From: Skip Montanaro <skip.montanaro@gmail.com>
To: Python <python-list@python.org>
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Xref: csiph.com comp.lang.python:81037

I discussion on the code-quality list got me thinking. Suppose I have
an old-style class in a 2.x app:

class Foo:
  def __init__(self):
    blah blah blah

I still use 2.x exclusively, but anytime I run pylint over a bit of
code and it complains that Foo is old-school, I make the obvious
change to inherit from object. While I do this mostly to shut up
pylint so I can focus on more serious messages, I must admit I have
never experienced any problem changing from old-style to new-style
classes. Under what circumstances might this be problematic?

Thx,

Skip