how to test for a dependency

[Steven Bethard]

Darren Dale wrote:
> I would like to test that latex is installed on a windows, mac or linux
> machine. What is the best way to do this? This should work:
> 
> if os.system('latex -v'):
>     print 'please install latex'
> 
> but I dont actually want the latex version information to print to screen. I
> tried redirecting sys.stdout to a file, but that doesnt help. Is there a
> better way to do this in a cross-platform friendly way?

I've been using Trent's which package[1] for this kind of thing:

import which
try:
     latex = which.which('latex')
except which.WhichError:
     print 'please install latex'


STeVe

[1] http://starship.python.net/crew/tmick/#which