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Date: Fri, 15 Apr 2011 17:35:20 +1000
Subject: Re: Pythonic infinite for loop?
From: Chris Angelico <rosuav@gmail.com>
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:3247

On Fri, Apr 15, 2011 at 5:24 PM, Paul Rubin <no.email@nospam.invalid> wrote=
:
> This does 2 lookups per key, which you could avoid by making the code
> uglier (untested):
>
> =A0 sentinel =3D object()
> =A0 seq =3D (dct.get('Keyword%d'%i,sentinel) for i in count(1))
> =A0 lst =3D list(takewhile(lambda x: x !=3D sentinel, seq))

If I understand this code correctly, that's creating generators,
right? It won't evaluate past the sentinel at all?

That might well be what I'm looking for. A bit ugly, but efficient and
compact. And I can bury some of the ugliness away.

Chris Angelico