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From: Oscar Benjamin <oscar.j.benjamin@gmail.com>
Date: Thu, 11 Jul 2013 17:34:33 +0100
Subject: Re: xslice idea | a generator slice
To: Russel Walker <russ.pobox@gmail.com>
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Xref: csiph.com comp.lang.python:50466

On 11 July 2013 17:21, Russel Walker <russ.pobox@gmail.com> wrote:
> To confess, this is the second time I've made the mistake of trying to im=
plement generator like functionality of a builtin when there already is on =
in itertools. Need to start studying that module abit more I think. I'm loo=
king at the docs now and I see there are actually a couple of isomethings()=
.

Your xslice (or mine) would still be better than islice when the step
size is large; islice has to iterate over all the skipped elements
which could be wasteful if the input is indexable. Also islice doesn't
support negative values for start, stop or step which xslice does.