Re: Which standard?

From	anton@mips.complang.tuwien.ac.at (Anton Ertl)
Newsgroups	comp.lang.forth
Subject	Re: Which standard?
Date	2012-03-26 09:50 +0000
Organization	Institut fuer Computersprachen, Technische Universitaet Wien
Message-ID	<2012Mar26.115002@mips.complang.tuwien.ac.at> (permalink)
References	(5 earlier) <jkj7om$tlv$1@speranza.aioe.org> <4f6da789$0$6930$e4fe514c@news2.news.xs4all.nl> <jkle53$kg$1@speranza.aioe.org> <4f6e69ee$0$6866$e4fe514c@news2.news.xs4all.nl> <-fadnQFW4uDe5vPSnZ2dnUVZ_qqdnZ2d@supernews.com>

Show all headers | View raw

"Elizabeth D. Rather" <erather@forth.com> writes:
> There is certainly a persistent need for 0=, to test for a 
>value equal to zero. I'll admit there's not much need for 0<>, it's 
>there for the contingent that worships symmetry. Although I've used 0= 
>extensively, I don't think I've ever felt a need for 0<>.

Sure, if all you do with the result of 0<> is to feed it into IF or
WHILE right away (just like you do with the result of 0= in many
cases), then you can leave it away.  You can also leave it away if the
result is consumed by OR and the result of OR is only tested for
(non-)zeroness; or if the result is consumed by AND, the other operand
is known to be a well-formed flag, and the result of the AND is only
tested for (non-)zeroness.

Of course, the more of these kinds of things you do, the harder the
program becomes to maintain, so it may be better to stick in 0<> in a
few places where it is not (yet) necessary.

In any case, the number of uses of 0<> will be much less than for 0=.
And indeed in the Gforth sources I find 576 occurences of 0= and 67
occurences of 0<>.

An example where 0<> is definitely necessary:

    next-prelude @ 0<> prelude-mask and lastflags cset

- anton
-- 
M. Anton Ertl  http://www.complang.tuwien.ac.at/anton/home.html
comp.lang.forth FAQs: http://www.complang.tuwien.ac.at/forth/faq/toc.html
     New standard: http://www.forth200x.org/forth200x.html
   EuroForth 2011: http://www.euroforth.org/ef11/

Back to comp.lang.forth | Previous | Next — Previous in thread | Next in thread | Find similar

Thread

Which standard? Nomen Nescio <nobody@dizum.com> - 2012-03-21 15:13 +0100
  Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-21 10:37 -0500
    Re: Which standard? Nomen Nescio <nobody@dizum.com> - 2012-03-21 20:23 +0100
      Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-22 13:34 -0500
        Re: Which standard? Nomen Nescio <nobody@dizum.com> - 2012-03-26 20:40 +0200
          Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-26 15:00 -0500
            Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-26 11:18 -1000
              Re: Which standard? Bernd Paysan <bernd.paysan@gmx.de> - 2012-03-27 02:20 +0200
          Re: Which standard? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-27 10:10 +0000
            Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-27 08:31 -0500
            Re: Which standard? Fritz Wuehler <fritz@spamexpire-201203.rodent.frell.theremailer.net> - 2012-03-27 17:08 +0200
              Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-27 11:31 -0500
                Re: Which standard? Helmar Wodtke <helmwo@gmail.com> - 2012-03-27 09:35 -0700
                Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-27 11:47 -0500
                Re: Which standard? Helmar Wodtke <helmwo@gmail.com> - 2012-03-27 10:15 -0700
                Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-27 12:33 -0500
        Re: Which standard? Fritz Wuehler <fritz@spamexpire-201203.rodent.frell.theremailer.net> - 2012-03-26 21:00 +0200
          Re: Which standard? BruceMcF <agila61@netscape.net> - 2012-03-26 13:17 -0700
            Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-26 11:24 -1000
              Re: Which standard? Fritz Wuehler <fritz@spamexpire-201203.rodent.frell.theremailer.net> - 2012-03-27 17:07 +0200
          Re: Which standard? "Peter Knaggs" <pjk@bcs.org.uk> - 2012-03-27 00:54 +0100
    Re: Which standard? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-21 14:09 -0700
  Re: Which standard? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-21 15:47 +0000
    Re: Which standard? Nomen Nescio <nobody@dizum.com> - 2012-03-21 20:13 +0100
      Re: Which standard? BruceMcF <agila61@netscape.net> - 2012-03-21 15:07 -0700
      Re: Which standard? stephenXXX@mpeforth.com (Stephen Pelc) - 2012-03-22 10:14 +0000
        Re: Which standard? Nomen Nescio <nobody@dizum.com> - 2012-03-22 16:36 +0100
          Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-22 08:47 -1000
            Re: Which standard? Fritz Wuehler <fritz@spamexpire-201203.rodent.frell.theremailer.net> - 2012-03-23 15:19 +0100
              Re: Which standard? BruceMcF <agila61@netscape.net> - 2012-03-23 07:48 -0700
              Re: Which standard? "Peter Knaggs" <pjk@bcs.org.uk> - 2012-03-23 17:28 +0000
                Re: Which standard? Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2012-03-23 20:51 +0000
                Re: Which standard? "Peter Knaggs" <pjk@bcs.org.uk> - 2012-03-24 00:47 +0000
              Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-23 08:40 -1000
                Re: Which standard? Fritz Wuehler <fritz@spamexpire-201203.rodent.frell.theremailer.net> - 2012-03-26 04:42 +0200
              Re: Which standard? Bernd Paysan <bernd.paysan@gmx.de> - 2012-03-26 19:17 +0200
          Re: Which standard? Paul Rubin <no.email@nospam.invalid> - 2012-03-22 13:03 -0700
            Re: Which standard? Fritz Wuehler <fritz@spamexpire-201203.rodent.frell.theremailer.net> - 2012-03-23 19:20 +0100
          Re: Which standard? stephenXXX@mpeforth.com (Stephen Pelc) - 2012-03-22 21:15 +0000
          Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-22 17:54 -0400
            Re: Which standard? "The Other Rod Pemberton" <dontaskdonttell@pemberton.it> - 2012-03-23 18:12 +0100
              Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-23 20:39 -0400
                Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-23 16:05 -1000
                Re: Which standard? Paul Rubin <no.email@nospam.invalid> - 2012-03-23 23:11 -0700
                Re: Which standard? "A. K." <akk@nospam.org> - 2012-03-24 09:15 +0100
                Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-23 22:52 -1000
                Re: Which standard? "A. K." <akk@nospam.org> - 2012-03-24 10:16 +0100
                Re: Which standard? Paul Rubin <no.email@nospam.invalid> - 2012-03-24 11:25 -0700
                Re: Which standard? Mark Wills <markrobertwills@yahoo.co.uk> - 2012-03-24 04:17 -0700
                Re: Which standard? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-26 21:46 -0700
                Re: Which standard? Mark Wills <markrobertwills@yahoo.co.uk> - 2012-03-27 02:49 -0700
                Re: Which standard? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-27 22:45 -0700
              Re: Which standard? Paul Rubin <no.email@nospam.invalid> - 2012-03-23 23:06 -0700
                Re: Which standard? Fritz Wuehler <fritz@spamexpire-201203.rodent.frell.theremailer.net> - 2012-03-26 01:51 +0200
          Re: Which standard? Paul Rubin <no.email@nospam.invalid> - 2012-03-22 14:57 -0700
            Re: Which standard? Nomen Nescio <nobody@dizum.com> - 2012-03-23 12:48 +0100
      Re: Which standard? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-22 17:50 +0000
    Re: Which standard? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-21 13:37 -0700
  Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-21 17:07 -0400
    Re: Which standard? Nomen Nescio <nobody@dizum.com> - 2012-03-22 09:27 +0100
      Re: Which standard? hwfwguy@gmail.com - 2012-03-22 12:06 -0700
      Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-22 19:19 -0400
        Re: Which standard? Fritz Wuehler <fritz@spamexpire-201203.rodent.frell.theremailer.net> - 2012-03-23 13:02 +0100
    Re: Which standard? BruceMcF <agila61@netscape.net> - 2012-03-22 08:17 -0700
      Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-22 08:25 -1000
        Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-23 21:50 +0100
          Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-23 13:10 -1000
          Re: Which standard? Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-03-24 11:19 +0000
            Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-25 07:55 -0400
              Re: Which standard? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-26 09:12 +0000
          Re: Which standard? Mark Wills <markrobertwills@yahoo.co.uk> - 2012-03-24 04:06 -0700
        Re: Which standard? Fritz Wuehler <fritz@spamexpire-201203.rodent.frell.theremailer.net> - 2012-03-27 21:03 +0200
  Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-21 22:28 +0100
    Re: Which standard? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-21 16:36 -0700
      Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-22 05:15 -0400
        Re: Which standard? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-22 12:16 +0000
        Re: Which standard? Fritz Wuehler <fritz@spamexpire-201203.rodent.frell.theremailer.net> - 2012-03-23 01:26 +0100
          Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-22 15:37 -1000
            Re: Which standard? Fritz Wuehler <fritz@spamexpire-201203.rodent.frell.theremailer.net> - 2012-03-25 22:24 +0200
            Re: Which standard? "Peter Knaggs" <pjk@bcs.org.uk> - 2012-03-26 10:49 +0100
        Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-23 20:00 +0100
          Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-23 21:21 -0400
            Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-24 11:44 +0100
              Re: Which standard? Bernd Paysan <bernd.paysan@gmx.de> - 2012-03-26 18:51 +0200
        Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-23 22:16 +0100
          Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-23 13:21 -1000
            Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-24 01:33 +0100
              Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-23 16:06 -1000
                Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-24 11:44 +0100
              Re: Which standard? Jan Coombs <jan_2011-02@murray-microft.co.uk> - 2012-03-24 10:08 +0000
                Re: Which standard? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-24 14:31 +0000
          Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-23 21:24 -0400
            Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-24 11:54 +0100
              Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-24 17:25 -0400
                Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-24 13:43 -1000
                Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-25 01:43 +0100
                Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-24 15:56 -1000
                Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-25 22:49 +0200
                Re: Which standard? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-26 09:50 +0000
                Re: Which standard? "Peter Knaggs" <pjk@bcs.org.uk> - 2012-03-25 09:18 +0100
                Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-25 06:07 -0400
                Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-25 22:42 +0200
                Re: Which standard? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-26 09:04 +0000
                Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-26 04:39 -0500
                Re: Which standard? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-26 22:29 -0700
                Re: Which standard? Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-03-26 18:09 +0000
                Re: Which standard? BruceMcF <agila61@netscape.net> - 2012-03-26 11:37 -0700
                Re: Which standard? "A. K." <akk@nospam.org> - 2012-03-26 20:49 +0200
                Re: Which standard? BruceMcF <agila61@netscape.net> - 2012-03-26 13:22 -0700
                Re: Which standard? Helmar Wodtke <helmwo@gmail.com> - 2012-03-26 11:20 -0700
                Re: Which standard? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-27 11:59 +0000
                Re: Which standard? Helmar Wodtke <helmwo@gmail.com> - 2012-03-27 05:26 -0700
                Re: Which standard? "Peter Knaggs" <pjk@bcs.org.uk> - 2012-03-29 00:10 +0100
                Re: Which standard? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-29 00:51 -0700
                Re: Which standard? Marc Olschok <nobody@nowhere.invalid> - 2012-03-30 16:13 +0000
                Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-30 13:01 -0500
                Re: Which standard? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-30 09:18 -1000
                Re: Which standard? Alex McDonald <blog@rivadpm.com> - 2012-03-30 14:11 -0700
                Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-31 08:18 -0500
                Re: Which standard? Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-04-03 09:27 +0000
                Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-25 05:47 -0400
                Re: Which standard? BruceMcF <agila61@netscape.net> - 2012-03-25 07:49 -0700
              Re: Which standard? BruceMcF <agila61@netscape.net> - 2012-03-24 15:07 -0700
          Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-24 05:44 -0500
      Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-23 19:54 +0100
        Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-23 21:52 -0400
          Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-24 12:13 +0100
            Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-24 06:24 -0500
              Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-24 13:37 +0100
                Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-24 12:20 -0500
                Re: Which standard? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-24 17:24 -0400
        Re: Which standard? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-24 14:18 +0000
      Re: Which standard? Hans Bezemer <the.beez.speaks@gmail.com> - 2012-03-23 22:33 +0100
      Re: Which standard? Bernd Paysan <bernd.paysan@gmx.de> - 2012-03-26 03:25 +0200
      Re: Which standard? BruceMcF <agila61@netscape.net> - 2012-03-25 21:40 -0700
    Re: Which standard? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-22 04:15 -0500
    Re: Which standard? Fritz Wuehler <fritz@spamexpire-201203.rodent.frell.theremailer.net> - 2012-03-22 13:02 +0100
  Re: Which standard? Helmar Wodtke <helmwo@gmail.com> - 2012-03-25 08:51 -0700
  Re: Which standard? jacko <jackokring@gmail.com> - 2012-03-26 22:14 -0700
    Re: Which standard? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-26 23:55 -0700
      Re: Which standard? Helmar Wodtke <helmwo@gmail.com> - 2012-03-27 05:41 -0700
        Re: Which standard? hwfwguy@gmail.com - 2012-03-27 08:45 -0700
        Re: Which standard? Bernd Paysan <bernd.paysan@gmx.de> - 2012-03-28 01:42 +0200
          Re: Which standard? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-31 13:46 +0000
        Re: Which standard? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-27 22:51 -0700
        Re: Which standard? jacko <jackokring@gmail.com> - 2012-03-27 19:33 -0700

csiph-web