Re: Re: How to abort loops and other return stack fiddling words…

From	anton@mips.complang.tuwien.ac.at (Anton Ertl)
Newsgroups	comp.lang.forth
Subject	Re: Re: How to abort loops and other return stack fiddling words…
Date	2013-07-22 16:36 +0000
Organization	Institut fuer Computersprachen, Technische Universitaet Wien
Message-ID	<2013Jul22.183641@mips.complang.tuwien.ac.at> (permalink)
References	(1 earlier) <b161d7ea-6e05-4b66-bf53-b3f8542f2288@googlegroups.com> <ksj9pq$oll$1@dont-email.me> <76d79e90-f181-4c1d-afa0-3863760f22a9@googlegroups.com> <2013Jul22.180100@mips.complang.tuwien.ac.at> <ksjmeb$1vj$1@dont-email.me>

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rickman <gnuarm@gmail.com> writes:
>On 7/22/2013 12:01 PM, Anton Ertl wrote:
>> Mark Wills<markrobertwills@yahoo.co.uk>  writes:
>> Maybe that's your house style, but not everybody has to follow your
>> house style.  In standard Forth AGAIN is just an unconditional branch
>> backwards.  You can use it for building infinite loops, but also for
>> other purposes.
>
>Do you have examples of loops with exits that are better served by AGAIN 
>than they are with UNITL or WHILE?

First of all, AGAIN is a factor or REPEAT:

: repeat postpone again  postpone then ; immediate

I also think that, when you have multiple WHILEs, it's better to use
AGAIN instead of REPEAT.  Then you just use n THENs for n WHILEs, not
n-1 THENs.  E.g.:

BEGIN
  ... WHILE
    ... WHILE
      ... WHILE
        ...
AGAIN THEN THEN THEN

instead of 

BEGIN
  ... WHILE
    ... WHILE
      ... WHILE
        ...
REPEAT THEN THEN

- 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 2013: http://www.euroforth.org/ef13/

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How to abort loops and other return stack fiddling words… Christian Kellermann <ckeen@pestilenz.org> - 2013-07-22 11:54 +0200
  Re: How to abort loops and other return stack fiddling words… Mark Wills <markrobertwills@yahoo.co.uk> - 2013-07-22 04:18 -0700
    Re: How to abort loops and other return stack fiddling words… Christian Kellermann <ckeen@pestilenz.org> - 2013-07-22 14:31 +0200
      Re: How to abort loops and other return stack fiddling words… daveyrotten <danw8804@gmail.com> - 2013-07-22 08:31 -0700
    Re: How to abort loops and other return stack fiddling words… Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2013-07-22 13:56 +0100
      Re: How to abort loops and other return stack fiddling words… Mark Wills <markrobertwills@yahoo.co.uk> - 2013-07-22 06:46 -0700
        Re: Re: How to abort loops and other return stack fiddling words… anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-07-22 16:01 +0000
          Re: How to abort loops and other return stack fiddling words… rickman <gnuarm@gmail.com> - 2013-07-22 12:31 -0400
            Re: Re: How to abort loops and other return stack fiddling words… anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-07-22 16:36 +0000
            Re: How to abort loops and other return stack fiddling words "Ed" <invalid@invalid.com> - 2013-07-24 12:18 +1000
            Re: How to abort loops and other return stack fiddling words? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-24 02:48 -0500
              Re: How to abort loops and other return stack fiddling words? rickman <gnuarm@gmail.com> - 2013-07-27 22:15 -0400
                Re: How to abort loops and other return stack fiddling words? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-28 03:37 -0500
                Re: How to abort loops and other return stack fiddling words? rickman <gnuarm@gmail.com> - 2013-07-29 11:01 -0400
                Re: How to abort loops and other return stack fiddling words? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-29 11:07 -0500
                Re: How to abort loops and other return stack fiddling words? rickman <gnuarm@gmail.com> - 2013-07-29 12:32 -0400
                Re: How to abort loops and other return stack fiddling words? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-29 11:54 -0500
                Re: How to abort loops and other return stack fiddling words? rickman <gnuarm@gmail.com> - 2013-07-29 13:19 -0400
                Re: How to abort loops and other return stack fiddling words? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-29 15:27 -0500
                Re: How to abort loops and other return stack fiddling words? Mark Wills <markrobertwills@yahoo.co.uk> - 2013-07-28 03:20 -0700
                Re: How to abort loops and other return stack fiddling words? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-28 08:17 -0500
        Re: How to abort loops and other return stack fiddling words… Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2013-07-22 18:07 +0100
      Re: Re: How to abort loops and other return stack fiddling words… albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-07-22 14:12 +0000
        Re: How to abort loops and other return stack fiddling words… Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2013-07-22 17:49 +0100
      Re: How to abort loops and other return stack fiddling words… hughaguilar96@yahoo.com - 2013-07-22 20:25 -0700
  Re: How to abort loops and other return stack fiddling words? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-07-22 07:54 -0500

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