[Python-Dev] PEP for Better Control of Nested Lexical Scopes (original) (raw)

James Y Knight foom at fuhm.net
Fri Feb 24 16:40:57 CET 2006

On Feb 24, 2006, at 1:54 AM, Greg Ewing wrote:

Thomas Wouters wrote:

On Thu, Feb 23, 2006 at 05:25:30PM +1300, Greg Ewing wrote:

As an aside, is there any chance that this could be changed in 3.0? I.e. have the for-loop create a new binding for the loop variable on each iteration. You can't do that without introducing a whole new scope for the body of the 'for' loop, There's no need for that. The new scope need only include the loop variable -- everything else could still refer to the function's main scope.

No, that would be insane. You get the exact same problem, now even
more confusing:

l=[] for x in range(10): y = x l.append(lambda: (x, y))

print l0

With your suggestion, that would print (0, 9).

Unless python grows a distinction between creating a binding and
assigning to one as most other languages have, this problem is here
to stay.

James

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