Re: What is xrange?

From	Gregory Ewing <greg.ewing@canterbury.ac.nz>
Newsgroups	comp.lang.python
Subject	Re: What is xrange?
Date	2011-07-31 12:18 +1200
Message-ID	<99jlaoFv7lU1@mid.individual.net> (permalink)
References	<j0v23e$g6o$1@speranza.aioe.org> <4e335ce4$0$29977$c3e8da3$5496439d@news.astraweb.com> <mailman.1654.1312025049.1164.python-list@python.org>

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Brian Blais wrote:
> On Jul 29, 2011, at 9:22 PM, Steven D'Aprano wrote:
> 
>>Billy Mays wrote:
>>
>>>Is xrange not a generator?  I know it doesn't return a tuple or list, so
>>>what exactly is it?

It's an iterable object.

There are advantages in having xrange (or range in python3) return
an iterable object, rather than creating an iterator directly.
One of them is that you can iterate over the same object more
than once.

This can be useful if you're iterating over a multi-dimensional
space of some kind. Some efficiency can be gained by pre-creating
an xrange object for each of the inner loops and re-using them.

-- 
Greg

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Thread

What is xrange? Billy Mays <noway@nohow.com> - 2011-07-29 15:36 -0400
  Re: What is xrange? harrismh777 <harmar@member.fsf.org> - 2011-07-29 14:47 -0500
  Re: What is xrange? Thomas Jollans <t@jollybox.de> - 2011-07-29 22:31 +0200
  Re: What is xrange? Jerry Hill <malaclypse2@gmail.com> - 2011-07-29 16:36 -0400
  Re: What is xrange? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-07-30 11:22 +1000
    Re: What is xrange? Brian Blais <bblais@bryant.edu> - 2011-07-30 06:23 -0400
      Re: What is xrange? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-07-30 21:36 +1000
        Re: What is xrange? Brian Blais <bblais@bryant.edu> - 2011-07-30 09:46 -0400
        Re: What is xrange? Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2011-07-30 17:06 -0700
        Re: What is xrange? Chris Angelico <rosuav@gmail.com> - 2011-07-31 01:10 +0100
        Re: What is xrange? Ethan Furman <ethan@stoneleaf.us> - 2011-07-30 23:42 -0700
      Re: What is xrange? Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2011-07-31 12:18 +1200

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