Re: l = range(int(1E9))

From	BartC <bc@freeuk.com>
Newsgroups	comp.lang.python
Subject	Re: l = range(int(1E9))
References	(6 earlier) <mailman.15.1430584786.12865.python-list@python.org> <bN81x.386497$G53.218869@fx13.am4> <mailman.23.1430594149.12865.python-list@python.org> <CV91x.402510$zE7.111881@fx40.am4> <slrnmkah47.apd.jon+usenet@frosty.unequivocal.co.uk>
Message-ID	<dhc1x.319346$qW.51334@fx20.am4> (permalink)
Organization	virginmedia.com
Date	2015-05-02 23:33 +0100

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On 02/05/2015 22:40, Jon Ribbens wrote:
> On 2015-05-02, BartC <bc@freeuk.com> wrote:
>> So do I, I think, if no-one is willing to admit that the original way of
>> implementing range() was a glaring mistake.
>
> I think the issue is that nobody else here thinks the "original way"
> of iterating was to use range(), for anything other than extremely
> small ranges.

What /is/ the way to iterate then?

I don't have much Python code lying around, but the first couple of 
files I looked at (not mine), one had this:

   for i in range(7,-1,-1):
     for j in range(8):

another had:

     for l in range(1,17):
       for i in range(1, self.bits[l] + 1):

     for i in range(256):

and so on. Plenty of examples. This was probably converted to Python 
from elsewhere, but why shouldn't it be able to run code trivially 
converted from somewhere else, without being unnecessarily slow? (What 
would be the 'Pythonic' way of writing a Jpeg decoder, as this was, anyway?)

I don't think the small size of the range is a mitigating factor, other 
than it won't run out of memory. Even a small loop can be executed 
millions of times.

> For information, it looks like xrange() was added on 26 Oct 1993,
> which pre-dates Python 1.0.

OK, so it's just an irritation then, as a workaround has been available 
for a long time. (For example, if you use xrange, it won't work on 3.x. 
If you use range, then it might be inefficient on 2.x.)

-- 
Bartc

Thread

l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-04-30 18:06 +0200
  Re: l = range(int(1E9)) Grant Edwards <invalid@invalid.invalid> - 2015-04-30 16:33 +0000
    Re: l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-04-30 19:26 +0200
      Re: l = range(int(1E9)) Ben Finney <ben+python@benfinney.id.au> - 2015-05-01 03:41 +1000
        Re: l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-04-30 20:44 +0200
    Re: l = range(int(1E9)) Roel Schroeven <roel@roelschroeven.net> - 2015-04-30 21:40 +0200
  Re: l = range(int(1E9)) Jon Ribbens <jon+usenet@unequivocal.co.uk> - 2015-04-30 16:55 +0000
    Re: l = range(int(1E9)) Ben Finney <ben+python@benfinney.id.au> - 2015-05-01 03:20 +1000
      Re: l = range(int(1E9)) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-01 15:20 +1000
        Re: l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-05-01 08:08 +0200
      Re: l = range(int(1E9)) BartC <bc@freeuk.com> - 2015-05-02 16:26 +0100
        Re: l = range(int(1E9)) Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-05-02 16:40 +0100
          Re: l = range(int(1E9)) BartC <bc@freeuk.com> - 2015-05-02 17:17 +0100
            Re: l = range(int(1E9)) Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-05-02 17:39 +0100
              Re: l = range(int(1E9)) BartC <bc@freeuk.com> - 2015-05-02 19:34 +0100
                Re: l = range(int(1E9)) Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-05-02 20:15 +0100
                Re: l = range(int(1E9)) Marko Rauhamaa <marko@pacujo.net> - 2015-05-02 22:26 +0300
                Re: l = range(int(1E9)) BartC <bc@freeuk.com> - 2015-05-02 20:51 +0100
                Re: l = range(int(1E9)) Joel Goldstick <joel.goldstick@gmail.com> - 2015-05-02 17:21 -0400
                Re: l = range(int(1E9)) Ian Kelly <ian.g.kelly@gmail.com> - 2015-05-02 15:31 -0600
                Re: l = range(int(1E9)) Jon Ribbens <jon+usenet@unequivocal.co.uk> - 2015-05-02 21:40 +0000
                Re: l = range(int(1E9)) Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-05-02 23:26 +0100
                Re: l = range(int(1E9)) BartC <bc@freeuk.com> - 2015-05-02 23:33 +0100
                Re: l = range(int(1E9)) Jon Ribbens <jon+usenet@unequivocal.co.uk> - 2015-05-03 00:13 +0000
                Re: l = range(int(1E9)) Michael Torrie <torriem@gmail.com> - 2015-05-02 20:07 -0600
                Re: l = range(int(1E9)) Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-05-03 03:16 +0100
                Re: l = range(int(1E9)) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-03 21:16 +1000
                Re: l = range(int(1E9)) Chris Angelico <rosuav@gmail.com> - 2015-05-03 21:30 +1000
                Re: l = range(int(1E9)) Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-05-03 19:36 +0100
                Re: l = range(int(1E9)) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-03 21:15 +1000
                Re: l = range(int(1E9)) Chris Angelico <rosuav@gmail.com> - 2015-05-03 21:29 +1000
                Re: l = range(int(1E9)) Terry Reedy <tjreedy@udel.edu> - 2015-05-02 19:26 -0400
                Re: l = range(int(1E9)) Jon Ribbens <jon+usenet@unequivocal.co.uk> - 2015-05-03 00:01 +0000
                Re: l = range(int(1E9)) Terry Reedy <tjreedy@udel.edu> - 2015-05-02 23:18 -0400
                Re: l = range(int(1E9)) Jon Ribbens <jon+usenet@unequivocal.co.uk> - 2015-05-03 03:40 +0000
                Re: l = range(int(1E9)) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-03 21:05 +1000
                Re: l = range(int(1E9)) Terry Reedy <tjreedy@udel.edu> - 2015-05-02 19:51 -0400
                Re: l = range(int(1E9)) Ian Kelly <ian.g.kelly@gmail.com> - 2015-05-02 22:51 -0600
                Re: l = range(int(1E9)) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-03 21:21 +1000
                Re: l = range(int(1E9)) Marko Rauhamaa <marko@pacujo.net> - 2015-05-02 22:15 +0300
            Re: l = range(int(1E9)) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-03 20:32 +1000
              Re: l = range(int(1E9)) Chris Angelico <rosuav@gmail.com> - 2015-05-03 20:59 +1000
        Re: l = range(int(1E9)) Terry Reedy <tjreedy@udel.edu> - 2015-05-02 18:41 -0400
    Re: l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-04-30 19:28 +0200
  Re: l = range(int(1E9)) Terry Reedy <tjreedy@udel.edu> - 2015-04-30 13:02 -0400
  Re: l = range(int(1E9)) Gary Herron <gherron@digipen.edu> - 2015-04-30 10:05 -0700
    Re: l = range(int(1E9)) Rob Gaddi <rgaddi@technologyhighland.invalid> - 2015-04-30 17:12 +0000
      Re: l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-04-30 20:50 +0200
        Re: l = range(int(1E9)) Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-04-30 21:53 +0100
          Re: l = range(int(1E9)) ElChino <elchino@cnn.cn> - 2015-04-30 23:23 +0200
            Re: l = range(int(1E9)) Chris Angelico <rosuav@gmail.com> - 2015-05-01 08:45 +1000
              Re: l = range(int(1E9)) ElChino <elchino@cnn.cn> - 2015-05-01 01:03 +0200
            Re: l = range(int(1E9)) Ben Finney <ben+python@benfinney.id.au> - 2015-05-01 09:12 +1000
              Re: l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-05-01 07:04 +0200
                Re: l = range(int(1E9)) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-05-01 13:15 +0200
                Re: l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-05-01 14:22 +0200
                Re: l = range(int(1E9)) Terry Reedy <tjreedy@udel.edu> - 2015-05-01 22:00 -0400
            Use ‘python2’ or ‘python3’, explicit is better than implicit  (was: l = range(int(1E9))) Ben Finney <ben+python@benfinney.id.au> - 2015-05-01 09:19 +1000
              Re: Use 'python2' or 'python3', explicit is better than implicit  (was: l = range(int(1E9))) Rustom Mody <rustompmody@gmail.com> - 2015-04-30 19:24 -0700
            Re: l = range(int(1E9)) Chris Angelico <rosuav@gmail.com> - 2015-05-01 09:23 +1000
          Re: l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-05-01 06:19 +0200
            Re: l = range(int(1E9)) Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-05-01 05:41 +0100
            Re: l = range(int(1E9)) Michael Torrie <torriem@gmail.com> - 2015-05-01 07:25 -0600
              Re: l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-05-01 16:12 +0200
  Re: l = range(int(1E9)) Gisle Vanem <gvanem@yahoo.no> - 2015-04-30 20:23 +0200
    Re: l = range(int(1E9)) alister <alister.nospam.ware@ntlworld.com> - 2015-04-30 18:48 +0000
      Re: l = range(int(1E9)) Dave Angel <davea@davea.name> - 2015-04-30 14:59 -0400
        Re: l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-04-30 22:18 +0200
          Re: l = range(int(1E9)) Tim Chase <python.list@tim.thechases.com> - 2015-04-30 16:41 -0500
            Re: l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-05-01 07:19 +0200
  Re: l = range(int(1E9)) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-01 14:42 +1000
    Re: l = range(int(1E9)) Cecil Westerhof <Cecil@decebal.nl> - 2015-05-01 07:13 +0200
    Re: l = range(int(1E9)) Tony the Tiger <tony@tiger.invalid> - 2015-05-02 21:28 +0000
      Re: l = range(int(1E9)) Ian Kelly <ian.g.kelly@gmail.com> - 2015-05-02 15:32 -0600
      Re: l = range(int(1E9)) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-03 20:56 +1000

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