DO... LOOP question

From	Arnold Doray <invalid@invalid.com>
Newsgroups	comp.lang.forth
Subject	DO... LOOP question
Date	2012-03-18 15:52 +0000
Organization	A noiseless patient Spider
Message-ID	<jk50b8$i6f$1@dont-email.me> (permalink)

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Dear Forthers, 

The '93 spec shows how to define ELSE, REPEAT and WHILE in terms of IF, 
THEN, BEGIN, AGAIN, UNTIL, AHEAD, CS-ROLL and CS-PICK. I was wondering if 
these primitives could be used to define DO ... LOOP and friends? 

I could only come up with an un-nestable solution: 


\ Repeat is from the '94 spec. 
: repeat
	postpone again
	postpone then ; immediate
	
: unloop 
	R> R> 2drop ; 	
	
: (loop-inc)
	R> + >R ; 
		
: (loop)
	postpone (loop-inc)
	postpone repeat
	postpone unloop	; immediate 

: +loop
	postpone (loop) ; immediate

: loop 
	1 postpone literal
	postpone +loop ; immediate

: (do-setup)
	swap >R >R ;
  
: (do-test)
  	R> dup R@ < swap >R ;  	
     
: do 
    postpone (do-setup)
    postpone begin
    postpone (do-test)
    postpone if 
    1 cs-roll ; immediate
	
: i R@ ; 	

Any suggestions? 

Thanks,
Arnold

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DO... LOOP question Arnold Doray <invalid@invalid.com> - 2012-03-18 15:52 +0000
  Re: DO... LOOP question Coos Haak <chforth@hccnet.nl> - 2012-03-18 17:08 +0100
  Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-18 09:41 -0700
    Re: DO... LOOP question Coos Haak <chforth@hccnet.nl> - 2012-03-18 20:51 +0100
      Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-18 14:37 -0700
    Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-18 15:56 -0700
      Re: DO... LOOP question Coos Haak <chforth@hccnet.nl> - 2012-03-19 01:04 +0100
        Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-18 17:25 -0700
        Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-18 17:43 -0700
          Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-18 18:48 -0700
        Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-18 21:49 -0700
          Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-19 11:39 -0700
          Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-20 12:16 -0700
    Re: DO... LOOP question Arnold Doray <invalid@invalid.com> - 2012-03-20 16:54 +0000
      Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-20 11:41 -0700
        Re: DO... LOOP question Arnold Doray <invalid@invalid.com> - 2012-03-24 17:29 +0000
          Re: DO... LOOP question Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-24 13:22 -0500
            Re: DO... LOOP question Arnold Doray <invalid@invalid.com> - 2012-03-25 04:09 +0000
              Re: DO... LOOP question Coos Haak <chforth@hccnet.nl> - 2012-03-25 13:49 +0200
                Re: DO... LOOP question Arnold Doray <invalid@invalid.com> - 2012-03-27 17:47 +0000
              Re: DO... LOOP question Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-03-25 19:45 +0000
              Re: DO... LOOP question Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-26 04:26 -0500
                Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-26 07:28 -0700
                Re: DO... LOOP question Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-26 10:03 -0500
                Re: DO... LOOP question Coos Haak <chforth@hccnet.nl> - 2012-03-26 18:47 +0200
                Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-26 09:53 -0700
                Re: DO... LOOP question Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-03-27 11:21 +0000
                Re: DO... LOOP question Helmar Wodtke <helmwo@gmail.com> - 2012-03-27 04:34 -0700
                Re: DO... LOOP question Coos Haak <chforth@hccnet.nl> - 2012-03-27 17:33 +0200
                Re: DO... LOOP question Helmar Wodtke <helmwo@gmail.com> - 2012-03-27 09:19 -0700
                Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-27 12:20 -0700
                Re: DO... LOOP question "Elizabeth D. Rather" <erather@forth.com> - 2012-03-27 09:34 -1000
                Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-27 13:00 -0700
              Re: DO... LOOP question Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-26 20:16 -0700
          Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-24 11:37 -0700
            Re: DO... LOOP question Arnold Doray <invalid@invalid.com> - 2012-03-25 06:39 +0000
              Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-25 06:19 -0700
      Re: DO... LOOP question "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-21 05:48 -0400
        Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-21 08:36 -0700
      Re: DO... LOOP question BruceMcF <agila61@netscape.net> - 2012-03-21 11:24 -0700
  Re: DO... LOOP question Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-21 03:01 -0700
    Re: DO... LOOP question Arnold Doray <invalid@invalid.com> - 2012-03-24 17:44 +0000
      Re: DO... LOOP question Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-03-25 11:57 +0000
      Re: DO... LOOP question Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-26 20:14 -0700
        Re: DO... LOOP question Arnold Doray <invalid@invalid.com> - 2012-03-27 16:46 +0000

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