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Re: c99 and the lack of warnings when int operations are applied to a bool

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Willem <willem@toad.stack.nl> writes:

> No, at least addition and multiplication are commonplace for boolean
> algebra in mathematics.

Yes, but does the mathematical definition fit the 'C' one?

If we think of boolean's as lying in Z_2 (i.e. integers mod 2) we have

1+1 (mod 2) = 2(mod 2) = 0.  

With 'C' we have true + true => 1 + 1 => 2 => true.

C boolean arithmetic is not Z_2 arithmetic.

There's no point appealing to the commonplace in mathematics, if
applying that mathematical logic in C programs will result in incorrect
answers.

And if we want boolean logic operators, we've already got them in 
~, &, | and ^

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c99 and the lack of warnings when int operations are applied to a bool mathog <dmathog@gmail.com> - 2012-03-23 08:40 -0700
  Re: c99 and the lack of warnings when int operations are applied to a bool James Kuyper <jameskuyper@verizon.net> - 2012-03-23 12:07 -0400
  Re: c99 and the lack of warnings when int operations are applied to a bool jacob navia <jacob@spamsink.net> - 2012-03-23 21:45 +0100
    Re: c99 and the lack of warnings when int operations are applied to a bool Robert Wessel <robertwessel2@yahoo.com> - 2012-03-23 17:17 -0500
      Re: c99 and the lack of warnings when int operations are applied to a bool jacob navia <jacob@spamsink.net> - 2012-03-23 23:29 +0100
        Re: c99 and the lack of warnings when int operations are applied   to a bool Ian Collins <ian-news@hotmail.com> - 2012-03-24 11:48 +1300
          Re: c99 and the lack of warnings when int operations are applied   to a bool jacob navia <jacob@spamsink.net> - 2012-03-24 23:47 +0100
            Re: c99 and the lack of warnings when int operations are applied   to a bool Willem <willem@toad.stack.nl> - 2012-03-25 09:05 +0000
              Re: c99 and the lack of warnings when int operations are applied   to a bool "BartC" <bc@freeuk.com> - 2012-03-25 11:30 +0100
                Re: c99 and the lack of warnings when int operations are applied   to a bool Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-03-25 21:05 +0100
                Re: c99 and the lack of warnings when int operations are applied   to a bool Lowell Gilbert <lgusenet@be-well.ilk.org> - 2012-03-25 16:15 -0400
                Re: c99 and the lack of warnings when int operations are applied   to a bool Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-03-25 22:14 +0100
                Re: c99 and the lack of warnings when int operations are applied   to a bool James Kuyper <jameskuyper@verizon.net> - 2012-03-25 23:46 -0400
                Re: c99 and the lack of warnings when int operations are applied to a bool Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-03-26 12:05 +0100
                Re: c99 and the lack of warnings when int operations are applied to a bool Lowell Gilbert <lgusenet@be-well.ilk.org> - 2012-03-26 15:22 -0400
              Re: c99 and the lack of warnings when int operations are applied to a bool Gareth Owen <gwowen@gmail.com> - 2012-03-25 11:44 +0100
                Re: c99 and the lack of warnings when int operations are applied to a bool Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-03-25 13:06 +0100
            Re: c99 and the lack of warnings when int operations are applied to a bool Tim Rentsch <txr@alumni.caltech.edu> - 2012-03-27 11:12 -0700
        Re: c99 and the lack of warnings when int operations are applied to a bool Robert Wessel <robertwessel2@yahoo.com> - 2012-03-24 01:15 -0500
          Re: c99 and the lack of warnings when int operations are applied to a bool jacob navia <jacob@spamsink.net> - 2012-03-24 23:29 +0100
    Re: c99 and the lack of warnings when int operations are applied to a bool mathog <dmathog@gmail.com> - 2012-03-27 09:53 -0700
      Re: c99 and the lack of warnings when int operations are applied to a bool Keith Thompson <kst-u@mib.org> - 2012-03-27 11:07 -0700
      Re: c99 and the lack of warnings when int operations are applied to a bool James Kuyper <jameskuyper@verizon.net> - 2012-03-27 14:16 -0400
      Re: c99 and the lack of warnings when int operations are applied to a bool Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-04-26 07:57 -0400
        Re: c99 and the lack of warnings when int operations are applied to a bool jacob navia <jacob@spamsink.net> - 2012-04-26 14:08 +0200
        Re: c99 and the lack of warnings when int operations are applied to a bool James Kuyper <jameskuyper@verizon.net> - 2012-04-26 09:09 -0400
          Re: c99 and the lack of warnings when int operations are applied to a bool Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-04-26 21:29 -0400
            Re: c99 and the lack of warnings when int operations are applied to a bool James Kuyper <jameskuyper@verizon.net> - 2012-04-26 21:58 -0400
              Re: c99 and the lack of warnings when int operations are applied to a bool Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-04-26 22:32 -0400
                Re: c99 and the lack of warnings when int operations are applied to a bool James Kuyper <jameskuyper@verizon.net> - 2012-04-27 06:31 -0400
                Re: c99 and the lack of warnings when int operations are applied to a bool ImpalerCore <jadill33@gmail.com> - 2012-04-27 08:31 -0700

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