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Re: all() is slow?

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Clearly what we need is a modern hygienic macro system to avoid this exec mess!

defmacro defall(name, cond):
    def name(lst):
        for a in lst:
            if not cond:
                return False
        return True

invoke defall(all, cond)

Only slightly tongue in cheek.

We have that stupid exec trick in the Python stdlib. It has to die.

http://hg.python.org/cpython/file/6bf07db23445/Lib/collections/__init__.py#l240

Devin

On Mon, Nov 7, 2011 at 5:06 PM, Chris Angelico <rosuav@gmail.com> wrote:
> On Tue, Nov 8, 2011 at 8:46 AM, david vierra <codewarrior0@gmail.com> wrote:
>> But, you didn't write an all() function.  You wrote a more specialized
>> allBoolean() function. I think this comparison is more fair to the
>> builtin all():
>
> So really, it's not "all() is slow" but "function calls are slow".
> Maybe it'd be worthwhile making an all-factory:
>
> def my_all(code,lst):
>    exec("""def tmp_all(x):
>        for a in x:
>            if not ("""+code+"""): return False
>        return True
> """)
>    return tmp_all(lst)
> timeit.timeit('my_all("a in (True, False)",x)','from __main__ import
> my_all,x',number=10)
>
> Bad code imho, but it _is_ faster than both the original and the builtin.
>
> ChrisA
> --
> http://mail.python.org/mailman/listinfo/python-list
>

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all() is slow? "OKB (not okblacke)" <brenNOSPAMbarn@NObrenSPAMbarn.net> - 2011-11-07 21:00 +0000
  Re: all() is slow? Chris Rebert <clp2@rebertia.com> - 2011-11-07 13:39 -0800
  Re: all() is slow? david vierra <codewarrior0@gmail.com> - 2011-11-07 13:46 -0800
    Re: all() is slow? Chris Angelico <rosuav@gmail.com> - 2011-11-08 09:06 +1100
      Re: all() is slow? Henrik Faber <hfaber@invalid.net> - 2011-11-08 13:09 +0100
        Re: all() is slow? Chris Angelico <rosuav@gmail.com> - 2011-11-08 23:14 +1100
        Re: all() is slow? John Posner <jjposner@optimum.net> - 2011-11-08 17:51 -0500
        Re: all() is slow? Tim Chase <python.list@tim.thechases.com> - 2011-11-08 17:56 -0600
    Re: all() is slow? Devin Jeanpierre <jeanpierreda@gmail.com> - 2011-11-08 19:44 -0500
      Re: all() is slow? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-09 02:47 +0000
        Re: all() is slow? Devin Jeanpierre <jeanpierreda@gmail.com> - 2011-11-09 18:01 -0500
          Re: all() is slow? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-09 23:11 +0000
            Re: all() is slow? Devin Jeanpierre <jeanpierreda@gmail.com> - 2011-11-09 20:26 -0500
              Re: all() is slow? alex23 <wuwei23@gmail.com> - 2011-11-09 19:50 -0800
                Re: all() is slow? Devin Jeanpierre <jeanpierreda@gmail.com> - 2011-11-09 23:40 -0500
                Re: all() is slow? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-10 07:35 +0000
              Re: all() is slow? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-10 07:48 +0000
                Re: all() is slow? Devin Jeanpierre <jeanpierreda@gmail.com> - 2011-11-10 03:51 -0500
                Re: all() is slow? gene heskett <gheskett@wdtv.com> - 2011-11-10 08:20 -0500
                Re: all() is slow? Terry Reedy <tjreedy@udel.edu> - 2011-11-10 14:25 -0500
            Re: all() is slow? Devin Jeanpierre <jeanpierreda@gmail.com> - 2011-11-09 20:35 -0500
            Re: all() is slow? Ian Kelly <ian.g.kelly@gmail.com> - 2011-11-09 19:10 -0700
            Re: all() is slow? Ethan Furman <ethan@stoneleaf.us> - 2011-11-10 10:43 -0800
            Re: all() is slow? Devin Jeanpierre <jeanpierreda@gmail.com> - 2011-11-10 15:37 -0500
              Re: all() is slow? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-10 23:07 +0000
                Re: all() is slow? Devin Jeanpierre <jeanpierreda@gmail.com> - 2011-11-10 23:35 -0500
                Re: all() is slow? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-12 01:18 +0000
                Re: all() is slow? Devin Jeanpierre <jeanpierreda@gmail.com> - 2011-11-13 01:28 -0500
                Re: all() is slow? alex23 <wuwei23@gmail.com> - 2011-11-13 18:50 -0800
                Re: all() is slow? Devin Jeanpierre <jeanpierreda@gmail.com> - 2011-11-13 23:48 -0500
              Re: all() is slow? "OKB (not okblacke)" <brenNOSPAMbarn@NObrenSPAMbarn.net> - 2011-11-11 05:40 +0000
            Re: all() is slow? Ian Kelly <ian.g.kelly@gmail.com> - 2011-11-10 14:19 -0700
              Re: all() is slow? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2011-11-10 22:56 +0000
            Re: all() is slow? Ethan Furman <ethan@stoneleaf.us> - 2011-11-10 13:47 -0800
        Re: all() is slow? Chris Angelico <rosuav@gmail.com> - 2011-11-10 10:15 +1100
    Re: all() is slow? Chris Angelico <rosuav@gmail.com> - 2011-11-09 12:19 +1100
    Re: all() is slow? Chris Rebert <clp2@rebertia.com> - 2011-11-08 17:30 -0800
      Re: all() is slow? Hans Mulder <hansmu@xs4all.nl> - 2011-11-09 16:41 +0100
        Re: all() is slow? Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2011-11-09 09:07 -0800
  Re: all() is slow? John Nagle <nagle@animats.com> - 2011-11-09 14:16 -0800
    Re: all() is slow? alex23 <wuwei23@gmail.com> - 2011-11-09 19:52 -0800
    Re: all() is slow? "OKB (not okblacke)" <brenNOSPAMbarn@NObrenSPAMbarn.net> - 2011-11-10 19:35 +0000
  Re: all() is slow? BOOK-AZ <amalguseynov@gmail.com> - 2011-11-15 08:02 -0800

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