Re: Arithmetic with Boolean values

From	Roy Smith <roy@panix.com>
Newsgroups	comp.lang.python
Subject	Re: Arithmetic with Boolean values
Date	2012-08-12 07:40 -0400
Organization	PANIX Public Access Internet and UNIX, NYC
Message-ID	<roy-34CDF6.07403012082012@news.panix.com> (permalink)
References	<58f60e60-1dc1-4265-a601-693d11b4bcec@googlegroups.com> <7x4no96ib3.fsf@ruckus.brouhaha.com> <502791ea$0$29978$c3e8da3$5496439d@news.astraweb.com>

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In article <502791ea$0$29978$c3e8da3$5496439d@news.astraweb.com>,
 Steven D'Aprano <steve+comp.lang.python@pearwood.info> wrote:

> for x in (0,) if len(L)%2 else (0, 1):
>     ...
> 
> which is even more explicit and simpler to read even though it is longer.

Ugh.

do_stuff()
if len(L) % 2 == 0:
   do_stuff()  # reprocess even-length list

Sure, it's 3 lines instead of one, but dead-obvious what the intention 
is.  I might even go for:

if len(L) % 2:
   do_stuff()
else:
   do_stuff()
   do_stuff()

There's two problems with all the looping suggestions people have given.  
One is that the computation of whether you need to do it once or twice 
is messy.  But, but bigger issue is you're trying to warp what's 
fundamentally a boolean value into a looping construct.  That's a 
cognitive mismatch.

Thread

Arithmetic with Boolean values John Ladasky <john_ladasky@sbcglobal.net> - 2012-08-11 15:30 -0700
  Re: Arithmetic with Boolean values Chris Angelico <rosuav@gmail.com> - 2012-08-12 09:13 +1000
  Re: Arithmetic with Boolean values Chris Rebert <clp2@rebertia.com> - 2012-08-11 16:53 -0700
  Re: Arithmetic with Boolean values Terry Reedy <tjreedy@udel.edu> - 2012-08-11 20:25 -0400
  Re: Arithmetic with Boolean values Chris Angelico <rosuav@gmail.com> - 2012-08-12 10:31 +1000
  Re: Arithmetic with Boolean values MRAB <python@mrabarnett.plus.com> - 2012-08-12 01:36 +0100
  Re: Arithmetic with Boolean values Paul Rubin <no.email@nospam.invalid> - 2012-08-11 17:54 -0700
    Re: Arithmetic with Boolean values Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-08-12 11:22 +0000
      Re: Arithmetic with Boolean values Roy Smith <roy@panix.com> - 2012-08-12 07:40 -0400
        Re: Arithmetic with Boolean values Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-08-12 14:06 +0000
          Re: Arithmetic with Boolean values Paul Rubin <no.email@nospam.invalid> - 2012-08-12 09:59 -0700
            Re: Arithmetic with Boolean values Bernd Nawothnig <Bernd.Nawothnig@t-online.de> - 2012-08-12 19:21 +0200
            Re: Arithmetic with Boolean values Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-12 19:20 +0100
              Re: Arithmetic with Boolean values Roy Smith <roy@panix.com> - 2012-08-12 14:45 -0400
              Re: Arithmetic with Boolean values Alister <alister.ware@ntlworld.com> - 2012-08-12 20:13 +0000
                Re: Arithmetic with Boolean values Gene Heskett <gheskett@wdtv.com> - 2012-08-12 20:29 -0400
                Re: Arithmetic with Boolean values Hans Mulder <hansmu@xs4all.nl> - 2012-08-14 18:32 +0200

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