Re: Quotations revisited

From	mhx@iae.nl (Marcel Hendrix)
Subject	Re: Quotations revisited
Newsgroups	comp.lang.forth
Message-ID	<58811288968435@frunobulax.edu> (permalink)
Date	2012-07-15 23:54 +0200
References	<50031807.129829772@192.168.0.50>
Organization	Wanadoo

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stephenXXX@mpeforth.com (Stephen Pelc) writes Re: Quotations revisited

> On Sat, 14 Jul 2012 15:55:03 +0200, mhx@iae.nl (Marcel Hendrix) wrote:

>>Recently, the subject of quotations popped up again and I remembered 
>>an unfinished project.

> Given the increasing popularity of talking about "quotations" and
> "closures", would someone like to specify them in Forth terminology.
> Andrew provided an implementation that only made sense to people
> with carnal knowledge of SwiftForth.

I'll answer in the hope to stand corrected :-)

A "quotation" is :noname definition that can be nested in another 
definition. Note that so far it would only be semantics;
obviously 

  :noname ( -- ) ." yeah" ; constant a
  : test  ( -- ) a execute ;

does the same as

  : test ( -- ) [: ." yeah" ;] execute ;

Technically, some systems may have problems allowing locals in a 
quotation, i.e. 

  : test ( -- ) 8 locals| x |  5 [: locals| x |  x 3 * . ;] execute  x . ;

A rather easy extension would be to let code access (not necessarily 
modify) the locals of the hosting definition (printing 24 here):

  : test ( -- ) 8 locals| x |  [: x 3 * . ;] execute ;

However, this is getting hairy:

  : test ( -- xt ) 8 locals| x |  [: x 3 * . ;] ;
  test execute  ( ? )

AFAIU, when the implementation is such that the quotation permanently 
'remembers' the value of 'x' (prints 24), this is called a 'closure.'

Knuth's Man-Or-Boy test creates a quotation that *modifies* the 
outer locals and then recursively calls its host, accessing outer 
locals that one might have expected to long gone out of
scope. It forces the quotation implementation to store copies of 
*all imaginable* outer locals and make them permanently available.

This can get even more interesting when a closure is required to
remember not only locals, but things like BASE, >IN, arbitrary 
variables, file handles, buffer addresses, etc..(*)

> I have seen two or three sets of requirements discussed, but for
> those of us who distinguish between hand-waving and specifications,
> would an interested party be prepared to specify what is required?

Maybe we first need a convincing example of the usefulness of 
quotations and closures -- (*) would certainly be useful, but 
the cost seems to be a little excessive?

-marcel

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Quotations revisited mhx@iae.nl (Marcel Hendrix) - 2012-07-14 15:55 +0200
  Re: Quotations revisited stephenXXX@mpeforth.com (Stephen Pelc) - 2012-07-15 19:26 +0000
    Re: Quotations revisited Bernd Paysan <bernd.paysan@gmx.de> - 2012-07-15 23:53 +0200
    Re: Quotations revisited mhx@iae.nl (Marcel Hendrix) - 2012-07-15 23:54 +0200
      Re: Quotations revisited Bernd Paysan <bernd.paysan@gmx.de> - 2012-07-16 00:48 +0200
        Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-22 15:01 +0000
          Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-23 16:49 +0000
            Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-23 21:39 +0000
              Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-25 13:13 +0000
        Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-22 11:07 -0500
          Re: Quotations revisited Paul Rubin <no.email@nospam.invalid> - 2012-07-22 10:21 -0700
            Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-22 12:35 -0500
              Re: Quotations revisited Paul Rubin <no.email@nospam.invalid> - 2012-07-22 11:39 -0700
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-22 15:16 -0500
                Re: Quotations revisited Paul Rubin <no.email@nospam.invalid> - 2012-07-22 14:35 -0700
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-23 04:18 -0500
                Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-23 12:58 +0000
                Re: Quotations revisited Paul Rubin <no.email@nospam.invalid> - 2012-07-23 11:55 -0700
                Re: Quotations revisited BruceMcF <agila61@netscape.net> - 2012-07-23 05:45 -0700
            Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-27 12:41 +0000
      Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-15 14:11 -1000
        Re: Quotations revisited "A. K." <akk@nospam.org> - 2012-07-16 07:47 +0200
          Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-16 13:56 +0000
            Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-16 07:20 -1000
              Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-17 13:49 +0000
        Re: Quotations revisited Mark Wills <markrobertwills@yahoo.co.uk> - 2012-07-16 02:32 -0700
          Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-27 12:58 +0000
        Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-16 04:32 -0500
          Re: Quotations revisited stephenXXX@mpeforth.com (Stephen Pelc) - 2012-07-16 11:41 +0000
            Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-16 07:40 -0500
              Re: Quotations revisited stephenXXX@mpeforth.com (Stephen Pelc) - 2012-07-16 14:05 +0000
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-16 09:20 -0500
                Re: Quotations revisited stephenXXX@mpeforth.com (Stephen Pelc) - 2012-07-16 15:46 +0000
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-16 11:33 -0500
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-16 15:32 +0000
                Re: Quotations revisited stephenXXX@mpeforth.com (Stephen Pelc) - 2012-07-16 17:56 +0000
                Re: Quotations revisited Bernd Paysan <bernd.paysan@gmx.de> - 2012-07-16 23:37 +0200
          Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-27 13:05 +0000
            Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-27 08:21 -0500
      Re: Quotations revisited Roelf Toxopeus <rt4all@notthis.hetnet.nl> - 2012-07-16 10:14 +0200
      Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-16 04:23 -0500
        Re: Quotations revisited m.a.m.hendrix@tue.nl - 2012-07-16 03:39 -0700
          Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-16 07:09 -0500
            Re: Quotations revisited mhx@iae.nl (Marcel Hendrix) - 2012-07-16 23:47 +0200
              Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-17 04:14 -0500
                Re: Quotations revisited Coos Haak <chforth@hccnet.nl> - 2012-07-17 17:39 +0200
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-17 12:18 -0500
                Re: Quotations revisited mhx@iae.nl (Marcel Hendrix) - 2012-07-17 20:26 +0200
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-19 16:21 +0000
                Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-19 15:58 -0700
      Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-16 14:05 +0000
    Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-16 12:47 +0000
      Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-16 08:56 -0500
      Re: Quotations revisited Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2012-07-16 15:04 +0100
        Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-16 09:23 -0500
          Re: Quotations revisited Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2012-07-16 17:38 +0100
            Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-16 12:58 -0500
        Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-16 14:56 +0000
      Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-16 22:53 +0000
        Re: Quotations revisited BruceMcF <agila61@netscape.net> - 2012-07-16 19:59 -0700
          Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-16 17:04 -1000
            Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-17 06:51 +0000
              Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-16 21:39 -1000
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-17 07:48 +0000
                Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-16 22:24 -1000
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-17 10:48 +0000
                Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-17 08:19 -1000
                Re: Quotations revisited Aleksej Saushev <asau@inbox.ru> - 2012-07-18 01:31 +0400
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-19 16:11 +0000
                Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-19 12:41 -1000
                Re: Quotations revisited Aleksej Saushev <asau@inbox.ru> - 2012-07-21 01:24 +0400
                Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-20 16:20 -1000
                Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-21 03:59 -0700
                Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-21 21:33 -1000
                Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-22 01:35 -0700
                Re: Quotations revisited Aleksej Saushev <asau@inbox.ru> - 2012-07-22 21:19 +0400
                Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-22 08:15 -1000
                Re: Quotations revisited Paul Rubin <no.email@nospam.invalid> - 2012-07-22 11:48 -0700
                Re: Quotations revisited Coos Haak <chforth@hccnet.nl> - 2012-07-22 21:48 +0200
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-22 15:22 -0500
                Re: Quotations revisited Paul Rubin <no.email@nospam.invalid> - 2012-07-22 14:50 -0700
                Re: Quotations revisited Paul Rubin <no.email@nospam.invalid> - 2012-07-22 15:08 -0700
                Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-22 15:20 -0700
                Re: Quotations revisited Aleksej Saushev <asau@inbox.ru> - 2012-07-23 03:29 +0400
                Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-22 14:22 -1000
                Re: Quotations revisited Aleksej Saushev <asau@inbox.ru> - 2012-07-23 05:46 +0400
                Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-22 21:46 -1000
                Re: Quotations revisited Aleksej Saushev <asau@inbox.ru> - 2012-07-25 03:31 +0400
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-23 16:50 +0000
                Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-23 07:57 -1000
                Re: Quotations revisited Aleksej Saushev <asau@inbox.ru> - 2012-07-25 03:38 +0400
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-26 13:01 +0000
                Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-21 12:10 +0000
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-21 09:19 -0500
                Re: Quotations revisited Bernd Paysan <bernd.paysan@gmx.de> - 2012-07-21 18:58 +0200
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-22 04:24 -0500
                Re: Quotations revisited Bernd Paysan <bernd.paysan@gmx.de> - 2012-07-22 14:25 +0200
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-22 11:11 -0500
                Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-21 19:29 +0000
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-23 16:31 +0000
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-23 12:21 -0500
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-23 17:32 +0000
                Re: Quotations revisited Paul Rubin <no.email@nospam.invalid> - 2012-07-23 11:23 -0700
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-24 03:28 -0500
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-25 13:15 +0000
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-25 11:47 -0500
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-26 13:06 +0000
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-26 09:50 -0500
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-26 15:11 +0000
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-26 11:06 -0500
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-26 16:46 +0000
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-27 04:52 -0500
                Re: Quotations revisited Paul Rubin <no.email@nospam.invalid> - 2012-07-26 09:48 -0700
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-27 14:51 +0000
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-28 08:29 -0500
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-23 16:17 +0000
                Re: Quotations revisited "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-07-22 18:41 -0400
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-23 16:53 +0000
            Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-17 12:22 +0000
              Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-17 07:30 -0500
                Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-17 06:34 -0700
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-17 09:04 -0500
                Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-18 07:07 -0700
                Re: Quotations revisited Coos Haak <chforth@hccnet.nl> - 2012-07-18 17:43 +0200
                Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-18 09:29 -0700
                Re: Quotations revisited Coos Haak <chforth@hccnet.nl> - 2012-07-18 20:59 +0200
                Re: Quotations revisited Coos Haak <chforth@hccnet.nl> - 2012-07-18 21:14 +0200
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-19 16:05 +0000
                Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-20 14:50 +0000
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-20 15:08 +0000
                Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-21 11:27 +0000
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-23 16:28 +0000
                Re: Quotations revisited Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-07-23 19:41 +0000
                Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-18 10:18 -0700
                Re: Quotations revisited anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-07-19 17:00 +0000
                Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-19 15:34 -0700
                Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-19 16:08 -0700
                Re: Quotations revisited Bernd Paysan <bernd.paysan@gmx.de> - 2012-07-17 20:09 +0200
  Re: Quotations revisited stephenXXX@mpeforth.com (Stephen Pelc) - 2012-07-16 12:01 +0000
    Re: Quotations revisited Paul Rubin <no.email@nospam.invalid> - 2012-07-16 10:42 -0700
      Re: Quotations revisited stephenXXX@mpeforth.com (Stephen Pelc) - 2012-07-16 18:06 +0000
        Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-16 11:08 -1000
          Re: Quotations revisited stephenXXX@mpeforth.com (Stephen Pelc) - 2012-07-16 21:38 +0000
            Re: Quotations revisited Bernd Paysan <bernd.paysan@gmx.de> - 2012-07-17 00:29 +0200
              Re: Quotations revisited "Elizabeth D. Rather" <erather@forth.com> - 2012-07-16 12:38 -1000
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-17 04:20 -0500
                Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-17 03:21 -0700
                Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-17 03:14 -0700
                Re: Quotations revisited Bernd Paysan <bernd.paysan@gmx.de> - 2012-07-17 19:58 +0200
                Re: Quotations revisited Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-07-17 13:05 -0500
  Re: Quotations revisited stephenXXX@mpeforth.com (Stephen Pelc) - 2012-07-20 11:12 +0000
    Re: Quotations revisited Alex McDonald <blog@rivadpm.com> - 2012-07-20 05:40 -0700
      Re: Quotations revisited stephenXXX@mpeforth.com (Stephen Pelc) - 2012-07-20 15:55 +0000
    Re: Quotations revisited Paul Rubin <no.email@nospam.invalid> - 2012-07-22 20:54 -0700
      Re: Quotations revisited Aleksej Saushev <asau@inbox.ru> - 2012-07-25 03:55 +0400

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