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Date: Mon, 30 May 2011 04:38:26 +1000
Subject: Re: scope of function parameters
From: Chris Angelico <rosuav@gmail.com>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:6561

On Mon, May 30, 2011 at 4:01 AM, Chris Rebert <clp2@rebertia.com> wrote:
> def foo():
> =A0 =A0print bar
> =A0 =A0bar =3D 42
>
> foo()
>
> =3D=3D=3D>
> Traceback (most recent call last):
> =A0File "<stdin>", line 1, in <module>
> =A0File "<stdin>", line 2, in foo
> UnboundLocalError: local variable 'bar' referenced before assignment

Wow

I thought it basically functioned top-down. You get a different error
on the print line if there's a "bar =3D 42" *after* it. This could make
debugging quite confusing.

Guess it's just one of the consequences of eschewing variable
declarations. Sure it's easier, but there's complications down the
road.

Chris Angelico