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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Thu, 11 Jul 2013 12:00:17 -0600
Subject: Re: xslice idea | a generator slice
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Xref: csiph.com comp.lang.python:50470

On Thu, Jul 11, 2013 at 10:34 AM, Oscar Benjamin
<oscar.j.benjamin@gmail.com> wrote:
> 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 i=
mplement 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 lo=
oking 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.

Ah, that's an interesting point.  Of course the corollary to that is
that xslice requires a sequence, not just an iterable.