python list comprehensions; compressing a list of lists?

Question

guys. I\'m trying to find the most elegant solution to a problem and wondered if python has anything built-in for what I\'m trying to do.

What I\'m doing is this. I

Answer 1

You could try itertools.chain(), like this:

import itertools
import os
dirs = ["c:\\usr", "c:\\temp"]
subs = list(itertools.chain(*[os.listdir(d) for d in dirs]))
print subs

itertools.chain() returns an iterator, hence the passing to list().