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Re: Comparisons and sorting of a numeric class....

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On Thu, Jan 15, 2015 at 12:23 AM, Andrew Robinson
<andrew3@r3dsolutions.com> wrote:
> Can you name any other language that *does* allow subclassing of
> booleans or creation of new boolean values?
>
> Yes. Several off the top of my head -- and I have mentioned these before.
> They generally come with the extra subclasses pre-created and the user
> doesn't get to create the classes, but only use them; none the less -- they
> have more than two values with which to do logic equations with.
>
> VHDL, Verilog, HDL, Silos III, and there are IEEE variants also.
> C/C++ historically allowed you to do it with instances included, although I
> am not sure it still does.

Sorry, let me rehprase my question. Of course there will be
special-purpose languages that allow you to do interesting things with
the logic values and operators. Can you name any other
*general-purpose* language that allows subclassing of booleans or
creation of new boolean values? If not, it seems rather unfair to
single out Python and marvel that this isn't allowed when it's
actually quite normal to disallow it. Unless you care to provide an
example, I am fairly sure your claim of C/C++ is wrong. The bool type
in C++ is a primitive type, none of which can be inherited from. C
doesn't even have a bool type; at most you have macros for true and
false to 1 and 0, so the "booleans" there are just ordinary integers.

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Re: Comparisons and sorting of a numeric class.... Andrew Robinson <andrew3@r3dsolutions.com> - 2015-01-12 17:59 -0800
  Re: Comparisons and sorting of a numeric class.... Steven D'Aprano <steve@pearwood.info> - 2015-01-13 05:32 +0000
    Re: Comparisons and sorting of a numeric class.... Chris Angelico <rosuav@gmail.com> - 2015-01-13 17:13 +1100
    Re: Comparisons and sorting of a numeric class.... Terry Reedy <tjreedy@udel.edu> - 2015-01-13 05:49 -0500
      Re: Comparisons and sorting of a numeric class.... Marko Rauhamaa <marko@pacujo.net> - 2015-01-13 13:00 +0200
        Re: Comparisons and sorting of a numeric class.... Chris Angelico <rosuav@gmail.com> - 2015-01-13 22:20 +1100
        Re: Comparisons and sorting of a numeric class.... Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-13 11:56 -0700
        Re: Comparisons and sorting of a numeric class.... Chris Angelico <rosuav@gmail.com> - 2015-01-14 06:02 +1100
    Re: Comparisons and sorting of a numeric class.... Chris Angelico <rosuav@gmail.com> - 2015-01-13 21:56 +1100
    Re: Comparisons and sorting of a numeric class.... Andrew Robinson <andrew3@r3dsolutions.com> - 2015-01-13 16:12 -0800
    Re: Comparisons and sorting of a numeric class.... Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-14 01:31 -0700
    Re: Comparisons and sorting of a numeric class.... Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-14 22:26 -0700
      Re: Comparisons and sorting of a numeric class.... Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2015-01-16 22:23 +1300
    Re: Comparisons and sorting of a numeric class.... Andrew Robinson <andrew3@r3dsolutions.com> - 2015-01-14 23:23 -0800
      Re: Comparisons and sorting of a numeric class.... Steven D'Aprano <steve@pearwood.info> - 2015-01-15 08:41 +0000
        Re: Comparisons and sorting of a numeric class.... Andrew Robinson <andrew3@r3dsolutions.com> - 2015-01-15 17:45 -0800
          Re: Comparisons and sorting of a numeric class.... Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-01-16 18:33 +1100
          Re: Comparisons and sorting of a numeric class.... Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2015-01-17 00:07 +1300
          Re: Comparisons and sorting of a numeric class.... Rustom Mody <rustompmody@gmail.com> - 2015-01-16 03:22 -0800
          Re: Comparisons and sorting of a numeric class.... Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-01-17 23:27 +1100
        Re: Comparisons and sorting of a numeric class.... Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-01-16 02:27 +0000
        Re: Comparisons and sorting of a numeric class.... Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-15 22:01 -0700
        Re: Comparisons and sorting of a numeric class.... Chris Angelico <rosuav@gmail.com> - 2015-01-16 17:58 +1100
      Re: Comparisons and sorting of a numeric class.... Rob Gaddi <rgaddi@technologyhighland.invalid> - 2015-01-15 09:54 -0800
        Re: Comparisons and sorting of a numeric class.... Andrew Robinson <andrew3@r3dsolutions.com> - 2015-01-26 15:47 -0800
        Re: Comparisons and sorting of a numeric class.... Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-26 18:50 -0700
    Re: Comparisons and sorting of a numeric class.... Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-15 10:05 -0700
    Re: Comparisons and sorting of a numeric class.... Andrew Robinson <andrew3@r3dsolutions.com> - 2015-01-23 03:46 -0800
      Re: Comparisons and sorting of a numeric class.... Rustom Mody <rustompmody@gmail.com> - 2015-01-23 07:31 -0800
        Re: Comparisons and sorting of a numeric class.... Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-23 09:50 -0700
          Re: Comparisons and sorting of a numeric class.... Rustom Mody <rustompmody@gmail.com> - 2015-01-23 09:03 -0800
            Re: Comparisons and sorting of a numeric class.... Chris Angelico <rosuav@gmail.com> - 2015-01-24 04:23 +1100
              Re: Comparisons and sorting of a numeric class.... Rustom Mody <rustompmody@gmail.com> - 2015-01-23 09:29 -0800
            Re: Comparisons and sorting of a numeric class.... Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-23 11:04 -0700
              Re: Comparisons and sorting of a numeric class.... Rustom Mody <rustompmody@gmail.com> - 2015-01-23 19:13 -0800
              Re: Comparisons and sorting of a numeric class.... Rustom Mody <rustompmody@gmail.com> - 2015-01-23 19:21 -0800
            Re: Comparisons and sorting of a numeric class.... Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-01-24 16:01 +1100
              Re: Comparisons and sorting of a numeric class.... Chris Angelico <rosuav@gmail.com> - 2015-01-24 16:43 +1100
          Re: Comparisons and sorting of a numeric class.... Rustom Mody <rustompmody@gmail.com> - 2015-01-23 09:22 -0800
            Re: Comparisons and sorting of a numeric class.... Chris Angelico <rosuav@gmail.com> - 2015-01-24 04:37 +1100
              Re: Comparisons and sorting of a numeric class.... Rustom Mody <rustompmody@gmail.com> - 2015-01-23 09:45 -0800
                Re: Comparisons and sorting of a numeric class.... Chris Angelico <rosuav@gmail.com> - 2015-01-24 05:03 +1100
                Re: Comparisons and sorting of a numeric class.... Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-23 11:13 -0700
      Re: Comparisons and sorting of a numeric class.... Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-01-24 19:27 +1100
    Re: Comparisons and sorting of a numeric class.... Chris Angelico <rosuav@gmail.com> - 2015-01-23 22:58 +1100
    Re: Comparisons and sorting of a numeric class.... Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-01-23 12:07 +0000
    Re: Comparisons and sorting of a numeric class.... Terry Reedy <tjreedy@udel.edu> - 2015-01-23 11:17 -0500
    Re: Comparisons and sorting of a numeric class.... Ian Kelly <ian.g.kelly@gmail.com> - 2015-01-23 11:00 -0700

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