Francis> But Skip, I am sure that you can easily find an example by Francis> yourself. For example, replace "+" by a function that does Francis> different things depending on its argument type.
Sure. I was thinking of the optimization use of type inferencing, forgetting the subject of the note. Coming back to this: 1- if a is None: 2- b = 1 3- else: 4- b = "Phew" 5- b = b + 1 pychecker should be able to warn you today (but it doesn't) that you are using b to refer to objects of two different types. It's not type inferencing, but it would probably be a reasonable addition to its suite of things it checks. Skip -- http://mail.python.org/mailman/listinfo/python-list