Newbie question - TclError

[Fredrik Lundh]

Simon Brunning <sbrunning at trisystems.co.uk> wrote:
> http://www.sunworld.com/sunworldonline/swol-02-1998/swol-02-python_p.html
> ...
> entry.bind("", evaluate)

if you look at the HTML source, you'll find that the line was
supposed to be:

    entry.bind("<Key-Return>", evaluate)

but the script is still buggy; to make the "submit" button
work, you have to change the evaluate command to:

    def evaluate(event=None):
        label['text'] = "Result:  " + str(eval(expression.get()))

</F>

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