Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.python > #38594

Re: LangWart: Method congestion from mutate multiplicty

References (1 earlier) <5115c455$0$6574$c3e8da3$5496439d@news.astraweb.com> <d405822d-2252-4a85-8ab2-38ca88963d91@googlegroups.com> <CAPTjJmrCK+LGo5ijg6S0p2q1jHKt-bFfuOZqFm3ZtuACOPaSdw@mail.gmail.com> <CAMjeLr_4Udj+LN8B7Wmjw9XVEx7VSVG7Kxu3cp4GA5Lo1tVhig@mail.gmail.com> <CAHVvXxTAy9r=pS2bf2rVW5rvBbhLFeByZ7NOOb9hD6P9m9PnZw@mail.gmail.com>
Date 2013-02-10 10:45 -0800
Subject Re: LangWart: Method congestion from mutate multiplicty
From Mark Janssen <dreamingforward@gmail.com>
Newsgroups comp.lang.python
Message-ID <mailman.1596.1360521910.2939.python-list@python.org> (permalink)

Show all headers | View raw

On Sun, Feb 10, 2013 at 5:30 AM, Oscar Benjamin
<oscar.j.benjamin@gmail.com> wrote:
> On 10 February 2013 04:53, Mark Janssen <dreamingforward@gmail.com> wrote:
>> I have to agree with Rick, I think requiring the user to explicitly
>> create a new object, which is already a good and widely-used practice,
>> should be the Only One Way to Do It.
>
> Why should I copy a potentially large data structure just to iterate
> over it in reverse order? And why on earth would you want to remove
> the more efficient ways of doing this?

You're right.  I responded too fast. I think reversed() and sorted()
might be the only legit methods in this regard and I thank Steve
D'Aprano for pointing that out.

But Rick still has a valid point: it should not be taken as a general
practice.  The point, as I see it, is that there's no clear,
documented standard on the "right way" for people to think about the
issue.  The existence of sorted() and reversed() actually *misinform*
programmers as if this is the best practice.  It isn't, it just that
these are very special cases (one for a real machine efficiency and
one for a very common "user efficiency") and there should probably be
documentation to make that clear, so programmers don't start going
that direction.  I don't think there are other cases where such an
idiom would be recommended.

Mark

Back to comp.lang.python | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-08 17:50 -0800
  Re: LangWart: Method congestion from mutate multiplicty Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-09 14:36 +1100
    Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-09 19:54 -0800
      Re: LangWart: Method congestion from mutate multiplicty Chris Angelico <rosuav@gmail.com> - 2013-02-10 15:20 +1100
      Re: LangWart: Method congestion from mutate multiplicty Mark Janssen <dreamingforward@gmail.com> - 2013-02-09 20:53 -0800
        Re: LangWart: Method congestion from mutate multiplicty Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-11 01:29 +1100
          Re: LangWart: Method congestion from mutate multiplicty Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-02-10 14:03 -0500
            Re: LangWart: Method congestion from mutate multiplicty Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-11 11:11 +1100
          Re: LangWart: Method congestion from mutate multiplicty Mark Janssen <dreamingforward@gmail.com> - 2013-02-10 13:28 -0800
            Re: LangWart: Method congestion from mutate multiplicty Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-11 11:10 +1100
              Re: LangWart: Method congestion from mutate multiplicty Mark Janssen <dreamingforward@gmail.com> - 2013-02-10 17:14 -0800
          Re: LangWart: Method congestion from mutate multiplicty Chris Angelico <rosuav@gmail.com> - 2013-02-11 08:51 +1100
          Re: LangWart: Method congestion from mutate multiplicty Mark Janssen <dreamingforward@gmail.com> - 2013-02-10 14:01 -0800
      Re: LangWart: Method congestion from mutate multiplicty Terry Reedy <tjreedy@udel.edu> - 2013-02-10 03:39 -0500
        Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-10 10:45 -0800
          Re: LangWart: Method congestion from mutate multiplicty Terry Reedy <tjreedy@udel.edu> - 2013-02-10 16:44 -0500
          Re: LangWart: Method congestion from mutate multiplicty Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-11 11:11 +1100
        Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-10 10:45 -0800
      Re: LangWart: Method congestion from mutate multiplicty Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-10 22:29 +1100
        Re: LangWart: Method congestion from mutate multiplicty Chris Angelico <rosuav@gmail.com> - 2013-02-11 00:24 +1100
          Re: LangWart: Method congestion from mutate multiplicty Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-11 01:00 +1100
        Re: LangWart: Method congestion from mutate multiplicty Tim Chase <python.list@tim.thechases.com> - 2013-02-10 07:52 -0600
        Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-10 15:59 -0800
          Re: LangWart: Method congestion from mutate multiplicty Tim Chase <python.list@tim.thechases.com> - 2013-02-10 18:12 -0600
            Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-10 17:24 -0800
            Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-10 17:24 -0800
          Re: LangWart: Method congestion from mutate multiplicty Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-11 11:36 +1100
            Re: LangWart: Method congestion from mutate multiplicty MRAB <python@mrabarnett.plus.com> - 2013-02-11 02:03 +0000
            Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-11 04:53 -0800
              Re: LangWart: Method congestion from mutate multiplicty Chris Angelico <rosuav@gmail.com> - 2013-02-12 00:27 +1100
                Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-11 20:55 -0800
                Re: LangWart: Method congestion from mutate multiplicty Mark Janssen <dreamingforward@gmail.com> - 2013-02-11 21:28 -0800
                Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-12 12:46 -0800
                Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-12 12:46 -0800
                Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-11 20:55 -0800
          Re: LangWart: Method congestion from mutate multiplicty alex23 <wuwei23@gmail.com> - 2013-02-10 18:05 -0800
            Re: LangWart: Method congestion from mutate multiplicty Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-02-11 07:19 +0000
            Re: LangWart: Method congestion from mutate multiplicty Chris Angelico <rosuav@gmail.com> - 2013-02-11 18:24 +1100
            Re: LangWart: Method congestion from mutate multiplicty Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-02-11 07:35 +0000
            Re: LangWart: Method congestion from mutate multiplicty Tim Chase <tim@thechases.com> - 2013-02-11 06:04 -0600
            Re: LangWart: Method congestion from mutate multiplicty Serhiy Storchaka <storchaka@gmail.com> - 2013-02-11 19:07 +0200
      Re: LangWart: Method congestion from mutate multiplicty Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2013-02-10 13:30 +0000
        Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-10 16:25 -0800
          Re: LangWart: Method congestion from mutate multiplicty Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-11 11:42 +1100
        Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-10 16:25 -0800
      Re: LangWart: Method congestion from mutate multiplicty Mark Janssen <dreamingforward@gmail.com> - 2013-02-10 10:45 -0800
    Re: LangWart: Method congestion from mutate multiplicty 88888 Dihedral <dihedral88888@googlemail.com> - 2013-02-10 06:33 -0800
  Re: LangWart: Method congestion from mutate multiplicty Chris Angelico <rosuav@gmail.com> - 2013-02-09 15:51 +1100
    Re: LangWart: Method congestion from mutate multiplicty alex23 <wuwei23@gmail.com> - 2013-02-10 17:56 -0800
      Re: LangWart: Method congestion from mutate multiplicty Chris Angelico <rosuav@gmail.com> - 2013-02-12 19:06 +1100
  Re: LangWart: Method congestion from mutate multiplicty Neil Hodgson <nhodgson@iinet.net.au> - 2013-02-10 20:53 +1100
    Re: LangWart: Method congestion from mutate multiplicty Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-10 22:30 +1100
    Re: LangWart: Method congestion from mutate multiplicty Rick Johnson <rantingrickjohnson@gmail.com> - 2013-02-10 10:55 -0800
      Re: LangWart: Method congestion from mutate multiplicty Neil Hodgson <nhodgson@iinet.net.au> - 2013-02-11 08:57 +1100

csiph-web