Author donmez
Recipients donmez
Date 2008-05-23.19:09:13
SpamBayes Score 3.74273e-05
Marked as misclassified No
Message-id <1211569769.38.0.125136210909.issue2952@psf.upfronthosting.co.za>
In-reply-to
Content
Originally found at http://www.randombit.net/weblog/programming/variable_leak_in_list_compre
hensions.html

First example :

[~]> python
Python 2.5.1 (r251:54863, Jan 17 2008, 19:35:17) 
[GCC 4.0.1 (Apple Inc. build 5465)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> x=1
>>> [x for x in [1,2,3]]
[1, 2, 3]
>>> x
3

whoops x changed.

Another example from original post:

$ python
Python 2.4.4 (#1, Mar  7 2008, 14:54:19)
[GCC 4.1.2 (Gentoo 4.1.2 p1.0.2)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> x = { 1:2, 3:4 }
>>> nothere
Traceback (most recent call last):
  File "", line 1, in ?
NameError: name 'nothere' is not defined
>>> [nothere for nothere in x.keys()]
[1, 3]
>>> nothere
3

This bug doesn't seem to affect py3k but it does python 2.4/2.5. Either 
this should be fixed or documented as a caveat.
History
Date User Action Args
2008-05-23 19:09:32donmezsetspambayes_score: 3.74273e-05 -> 3.74273e-05
recipients: + donmez
2008-05-23 19:09:29donmezsetspambayes_score: 3.74273e-05 -> 3.74273e-05
messageid: <1211569769.38.0.125136210909.issue2952@psf.upfronthosting.co.za>
2008-05-23 19:09:24donmezlinkissue2952 messages
2008-05-23 19:09:20donmezcreate