Re: variable declaration

[Brian van den Broek]

Brian van den Broek said unto the world upon 2005-02-07 20:36:
Steve Holden said unto the world upon 2005-02-07 17:51:
<SNIP>
The reason global is a wart can clearly be seen in the following example:
 >>> x = 3
 >>> def f(tf, v):
 ...   if tf:
 ...     global x
 ...   x = v
 ...
 >>> f(0, 5)
 >>> x
5
 >>>
<SNIP>
Hi,
Steve's example makes my brain hurt. :-)
I'd appreciate it if someone could tell me if I am understanding the 
example correctly. (My grasp of the terminology and issues at play is a 
bit shaky.)
<SNIP>
Thanks for any confirmation of my understanding / rectification of same. 
Best,

Brian vdB
Thanks to everyone whose contributed to this sub-thread! I've learned 
a lot. :-)

And, for posterity, some one wrote me off-list to correct my claim
that in
if False:
    # thousands of lines of code here
the thousands of lines "would never get executed". Simplifying their 
example, they pointed out:

>>> False = 'evil trickery'
>>> if False:
...     print 'Surprise!'
...
Surprise!
>>>
Which leads me naturally to the differences between 'if False:' and 
'if ):' that Duncan Booth pointed to. (Where'd I put the Tylenol.)

Thanks again to all,
Brian vdB
--
http://mail.python.org/mailman/listinfo/python-list