Roy Smith schreef:
I have a list, songs, which I want to divide into two groups.
Essentially, I want:
new_songs = [s for s in songs if s.is_new()]
old_songs = [s for s in songs if not s.is_new()]
but I don't want to make two passes over the list. I could do:
new_songs = []
old_songs = []
for s in songs:
if s.is_new():
new_songs.append(s)
else:
old_songs.append(s)
Which works, but is klunky compared to the two-liner above. This
seems like a common enough thing that I was expecting to find
something in itertools which did this. I'm thinking something along
the lines of:
matches, non_matches = isplit(lambda s: s.is_new, songs)
Does such a thing exist?
You could do something like:
new_songs, old_songs = [], []
[(new_songs if s.is_new() else old_songs).append(s) for s in songs]
But I'm not sure that that's any better than the long version.
--
"People almost invariably arrive at their beliefs not on the basis of
proof but on the basis of what they find attractive."
-- Pascal Blaise
r...@roelschroeven.net
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