Re: Arithmetic with Boolean values

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Date	Sun, 12 Aug 2012 09:13:15 +1000
Subject	Re: Arithmetic with Boolean values
From	Chris Angelico <rosuav@gmail.com>
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On Sun, Aug 12, 2012 at 8:30 AM, John Ladasky
<john_ladasky@sbcglobal.net> wrote:
> In [7]: 1 + not(len(L) % 2)
> ------------------------------------------------------------
>    File "<ipython console>", line 1
>      1 + not(len(L) % 2)
>            ^
> SyntaxError: invalid syntax

This appears to be a limitation of the parser; it's trying to
interpret "not" as a binary operator.

1 + (not(len(L) % 2))

Works just fine with parentheses to enforce the correct interpretation.

This also works in Python 3.2, fwiw (except that you need
list(range(5)) to create the sample list).

ChrisA

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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