[Python-3000] end scope of iteration variables after loop

[Richard Thomas]

I like that loop variables end up still in scope, as demonstrated so
far on this list it is quite useful, but only when there is a break
somewhere. The one that confuses me, therefore, is the dummy variables
in a generator expression leaking into the scope defining that
expression. Hence:

x = 0
L = [f(x) for x in range(2)]
assert x == 1

This is not particularly intuitive as the for loop in a generator
expression can never break; generator expressions feel more "closed".

Richard.

On Fri, Apr 18, 2008 at 2:15 PM, Facundo Batista
<facundobatista at gmail.com> wrote:
> 2008/4/18, Nicholas T <ntung at ntung.com>:
>
>
>  > Amaury - I think it's generally cleaner code to write
>  >     for myObject in someList:
>  >         if myObject.fits():
>  >            process(myObject)
>  >             break
>  > than
>  >    for myObject in someList:
>  >       if myObject.fits():
>  >          break
>  >    process(myObject)
>
>  See, I do this a lot:
>
>   for a, b, c  in someList:
>       if <some condition with a or b>:
>           break
>   else:
>       c = foobar
>   c.something()
>
>  Regards,
>
>  --
>  .    Facundo
>
>  Blog: http://www.taniquetil.com.ar/plog/
>  PyAr: http://www.python.org/ar/
>
>
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