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From: Serhiy Storchaka <storchaka@gmail.com>
Subject: Re: Split a list into two parts based on a filter?
Date: Wed, 12 Jun 2013 19:28:45 +0300
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Xref: csiph.com comp.lang.python:47816

12.06.13 09:32, Phil Connell написав(ла):
> On 12 Jun 2013 01:36, "Roy Smith" <roy@panix.com <mailto:roy@panix.com>>
> wrote:
>  > Well, continuing down this somewhat bizarre path:
>  >
>  > new_songs, old_songs = [], []
>  > itertools.takewhile(
>  >     lambda x: True,
>  >     (new_songs if s.is_new() else old_songs).append(s) for s in songs)
>  >     )
>  >
>  > I'm not sure I got the syntax exactly right, but the idea is anything
>  > that will iterate over a generator expression.  That at least gets rid
>  > of the memory requirement to hold the throw-away list :-)
>
> You could equivalently pass the generator to deque() with maxlen=0 -
> this consumes the iterator with constant memory usage.

any((new_songs if s.is_new() else old_songs).append(s) for s in songs)