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Re: Arithmetic with Boolean values

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John Ladasky <john_ladasky@sbcglobal.net> writes:
> I have gotten used to switching back and forth between Boolean algebra
> and numerical values.  Python generally makes this quite easy. 

Generally ugly though, at least to my tastes.  "Explicit is better
than implicit" as the saying goes.

> If the length of the list L is odd, I want to process it once.  If
> len(L) is even, I want to process it twice....
>   for x in range(1 + not(len(L) % 2)):

If you really have to do something like that, I'd say

   for x in range(1 + (len(L) & 1)):

or

   for x in range(2 - len(L) % 2): 

are simpler and avoid those bogus bool conversions.  I'd prefer to
just say the intention:

   for x in range(1 if len(L)%2==1 else 2):

> This provoked a SyntaxError. 

"not" is a syntactic keyword and "1 + not" is syntactically invalid.
You could write "1 + (not ...)" as you discovered, but really, it's
hackish.

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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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