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Re: In Forth, is it valid or safe to use the value of 'I' after LOOP?

From "Rod Pemberton" <do_not_have@noavailemail.cmm>
Newsgroups comp.lang.forth
Subject Re: In Forth, is it valid or safe to use the value of 'I' after LOOP?
Date 2012-03-06 18:20 -0500
Organization Aioe.org NNTP Server
Message-ID <jj665d$7br$1@speranza.aioe.org> (permalink)
References <jj3ats$bsb$1@speranza.aioe.org> <1KGdnU2taaxgpMjSnZ2dnUVZ_hGdnZ2d@supernews.com> <jj5lar$n8d$1@speranza.aioe.org> <MMGdnUxDfcbF_cvSnZ2dnUVZ_s6dnZ2d@supernews.com>

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"Elizabeth D. Rather" <erather@forth.com> wrote in message
news:MMGdnUxDfcbF_cvSnZ2dnUVZ_s6dnZ2d@supernews.com...
> On 3/6/12 8:33 AM, Rod Pemberton wrote:
> >> "Elizabeth D. Rather"<erather@forth.com>  wrote in message
> > news:1KGdnU2taaxgpMjSnZ2dnUVZ_hGdnZ2d@supernews.com...
> >>> On 3/5/12 11:23 AM, Rod Pemberton wrote:
> > [...]
> >
> >> I isn't a "variable" it's a word that pushes a *copy* of the current
> >> value of the loop counter onto the stack when it is executed. Once on
> >> the stack, it's like any other stack item, to use as you see fit.
> >
> > Yes, I noticed that ...  It seems that that also restricts the use of
> > 'I' to do "skip counters" too.  [...] It seems one would need to setup
> > a separate variable in Forth to perform the skip.
>
> If you need to manipulate the loop index, it's easy to do it with +LOOP.
> That's what it's for.
>

You don't find this mechanism clumsy or obtuse or awkward?

First, let us hide the loop counter behind a word that fetches it so no one
can modify the counter directly.  Next, let's create another word that is
used to add values to the counter since we no longer allow direct access to
the counter.  Now, let's create another word so we can add some other value
besides one to it, or well define LOOP in terms of +LOOP ...  Ah, only 3
words to access the index.  That's clearly insufficient!  Oh, let's create J
and K too, since implementing I by itself wasn't difficult enough.  Three
loop counters should do it.  Also, let's require DO to initialize I, J, and
K before we indicate which one we are going to use.  Now, that's a
challenge! And, let's make it so J and K can only be used in nested DO
LOOPS, respectively.  Now is DO hard enough for us to implement?  Ah, now 6
we've dedicated words to do what Forth can do with a variable and three
generic words.  We're definately on the "right" track with this looping
thing guys!  Oh, we forgot a way to exit the loop: LEAVE.  The Forth looping
mechanism *almost* seems perverse to me. But, hey, the cashier at McDonald's
basically threw my money out the window and let the wind blow it away.  So,
maybe I'm just cranky today.  If she stuffed it in her pocket, she'd be a
thief!  I didn't get my money.  Isn't that the same?  Since I didn't get it
and was owed it, can I claim they stole it?  That's the definition of
stealing ... right?  Or, is shoving your hand out the window and letting go
in the wind adequate and sufficient to comply with not "stealing" ones
money?  Insanity, just like I J K DO LOOP +LOOP /LOOP -LOOP LEAVE ...
When does it end? RfC for X Y Z *LOOP fibLOOP \LOOP :LOOP ;LOOP
?LOOP aLOOP bLOOP anyone?


Rod Pemberton

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In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-05 16:23 -0500
  Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-05 12:11 -1000
    Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-05 13:44 -1000
      Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-06 11:26 +0000
        Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? rickman <gnuarm@gmail.com> - 2012-03-06 05:42 -0800
          Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-06 14:51 +0000
            Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-06 10:17 -0600
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-06 16:49 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-06 11:56 -0600
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-06 18:07 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-07 04:14 -0600
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-12 15:56 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-12 11:23 -0500
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-12 16:26 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-12 12:28 -0500
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-06 13:36 -0500
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-06 09:18 -1000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? hwfwguy@gmail.com - 2012-03-06 20:14 -0800
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-07 08:22 -0800
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? rickman <gnuarm@gmail.com> - 2012-03-07 10:20 -0800
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-07 11:11 -0800
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? hwfwguy@gmail.com - 2012-03-07 19:07 -0800
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-08 10:11 -0800
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-12 09:36 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-12 16:01 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Alex McDonald <blog@rivadpm.com> - 2012-03-06 13:13 -0800
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-12 16:04 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-12 13:40 -0700
            Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? rickman <gnuarm@gmail.com> - 2012-03-07 10:15 -0800
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-07 10:33 -0800
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-07 17:16 -1000
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-12 11:18 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-12 08:01 -1000
          Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? jacko <jackokring@gmail.com> - 2012-03-15 18:59 -0700
            Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Coos Haak <chforth@hccnet.nl> - 2012-03-16 20:36 +0100
    Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-06 13:33 -0500
      Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-06 09:07 -1000
        Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-06 18:20 -0500
          Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-06 14:07 -1000
            Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? John Passaniti <john.passaniti@gmail.com> - 2012-03-06 16:53 -0800
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-06 19:26 -1000
            Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-10 19:04 -0500
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-10 18:44 -0800
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-11 17:06 -0400
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-11 17:01 -0700
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Paul E. Bennett" <Paul_E.Bennett@topmail.co.uk> - 2012-03-11 12:51 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-11 14:04 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Paul Rubin <no.email@nospam.invalid> - 2012-03-11 14:41 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-12 05:16 -0500
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-12 08:06 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Paul E. Bennett" <Paul_E.Bennett@topmail.co.uk> - 2012-03-11 21:55 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-11 17:17 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-03-12 11:00 +0000
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Josh Grams <josh@qualdan.com> - 2012-03-11 17:27 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Paul Rubin <no.email@nospam.invalid> - 2012-03-11 14:12 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Josh Grams <josh@qualdan.com> - 2012-03-11 21:48 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-11 14:24 -1000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-11 17:09 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-11 17:34 -0400
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-11 13:18 -1000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-11 17:32 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Josh Grams <josh@qualdan.com> - 2012-03-13 13:18 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-19 03:36 -0400
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? jacko <jackokring@gmail.com> - 2012-03-15 19:37 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-16 05:31 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-19 03:38 -0400
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-19 11:35 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Coos Haak <chforth@hccnet.nl> - 2012-03-16 20:39 +0100
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Mark Wills <markrobertwills@yahoo.co.uk> - 2012-03-12 12:50 -0700
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? jacko <jackokring@gmail.com> - 2012-03-15 19:27 -0700
          Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-07 08:16 -0800
          Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? jacko <jackokring@gmail.com> - 2012-03-15 19:09 -0700
  Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? rickman <gnuarm@gmail.com> - 2012-03-05 14:23 -0800
  Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? BruceMcF <agila61@netscape.net> - 2012-03-05 17:42 -0800
  Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? hwfwguy@gmail.com - 2012-03-06 09:36 -0800
  Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-03-08 10:41 +0000
  Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-08 05:38 -0800
    Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? hwfwguy@gmail.com - 2012-03-09 10:32 -0800
      Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-12 19:26 -0700
      Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-13 04:15 -0400
  Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Coos Haak <chforth@hccnet.nl> - 2012-03-12 01:11 +0100
    Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-12 19:41 -0400
      Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-12 16:46 -1000
        Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-12 21:17 -0700
          Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-13 05:01 -0400
            Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Mark Wills <markrobertwills@yahoo.co.uk> - 2012-03-13 03:06 -0700
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Paul Rubin <no.email@nospam.invalid> - 2012-03-13 12:32 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Mark Wills <markrobertwills@yahoo.co.uk> - 2012-03-13 14:01 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Paul Rubin <no.email@nospam.invalid> - 2012-03-14 11:47 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "A. K." <akk@nospam.org> - 2012-03-14 22:13 +0100
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-14 03:39 -0500
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Elizabeth D. Rather" <erather@forth.com> - 2012-03-14 06:54 -1000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-14 16:39 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-03-15 10:49 +0000
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Alex McDonald <blog@rivadpm.com> - 2012-03-14 08:53 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "A. K." <akk@nospam.org> - 2012-03-14 17:01 +0100
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? George Hubert <georgeahubert@yahoo.co.uk> - 2012-03-14 11:21 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "A. K." <akk@nospam.org> - 2012-03-14 19:25 +0100
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? Hugh Aguilar <hughaguilar96@yahoo.com> - 2012-03-14 16:37 -0700
                Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-15 04:28 -0400
            Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "David N. Williams" <williams@umich.edu> - 2012-03-13 16:19 -0400
              Re: In Forth, is it valid or safe to use the value of 'I' after LOOP? "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-14 20:13 -0400

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