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[Python-Dev] accumulator display syntax

Alex Martelli aleaxit at yahoo.com
Mon Oct 20 03:44:30 EDT 2003 
On Monday 20 October 2003 02:08 am, Greg Ewing wrote:
> "Phillip J. Eby" <pje at telecommunity.com>:
> > If you look at it this way, then you can consider [x for x in S] to be
> > shorthand syntax for list(x for x in S), as they would both produce the
> > same result.  However, IIRC, the current listcomp implementation actually
> > binds 'x' in the current local namespace, whereas the generator version
> > would not.
>
> Are we sure about that?

We are indeed sure (sadly) that list comprehensions leak control variable 
names.  We can hardly be sure of what iterator comprehensions would be
defined to do, given they don't exist, but surely we can HOPE that in an
ideal world where iterator comprehensions were part of Python they would
not be similarly leaky:-).


Alex
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