Can't get around "IndexError: list index out of range"

[Steve Holden]

erikwickstrom at gmail.com wrote:
> Hi all,
> 
> I'm sorry about the newbie question, but I've been searching all
> afternoon and can't find the answer!
> 
> I'm trying to get this bit of code to work without triggering the
> IndexError.
> 
> import shutil, os, sys
> 
> if sys.argv[1] != None:
>     ver = sys.argv[1]
> else:
>     ver = '2.14'
> 
> Of course, whenever I run it, I get list index out of range.
> 
> I'm coming from the php world where I can do:
> if $_GET['var'] != Null {
>   $ver = $_GET['var'];
> } else {
>   $ver = '2.14';
> }
> 
> Can anyone tell me how to make this work in python?
> 
Well all the advice you've had so far seems good, but of course the 
simplest way is just to test the length of the sequence before you try 
to address its second element:

if len(sys.argv) > 1:
   ver = sys.argv[1]
else:
   ver = "2.14"

regards
  Steve
-- 
Steve Holden       +44 150 684 7255  +1 800 494 3119
Holden Web LLC/Ltd          http://www.holdenweb.com
Skype: holdenweb       http://holdenweb.blogspot.com
Recent Ramblings     http://del.icio.us/steve.holden