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Groups > comp.lang.forth > #21209
| Date | 2013-03-28 08:41 -1000 |
|---|---|
| From | "Elizabeth D. Rather" <erather@forth.com> |
| Organization | FORTH, Inc. |
| Newsgroups | comp.lang.forth |
| Subject | Re: Can i rely on >BODY for anything at all? |
| References | (8 earlier) <kika1g$heu$1@speranza.aioe.org> <1v285cgumns8o.ksjt8alr76k9$.dlg@40tude.net> <kilh5a$hgk$2@online.de> <kiqvfc$rg5$1@speranza.aioe.org> <kj1665$oql$1@speranza.aioe.org> |
| Message-ID | <24Odne2AF55QE8nMnZ2dnUVZ_q2dnZ2d@supernews.com> (permalink) |
On 3/28/13 12:32 AM, Ed wrote: > Ed wrote: >> ... >> I never considered extending the semantics of >BODY. The issue is >> whether XT can provide enough information for every object one >> might wish to apply. If it can't, then a parsing alternative would be the >> way to go. > > The history of ' (tick) is both interesting and convoluted. > > In early Forths (and Forth-79) tick returned the *parameter* field address. > And in PolyForth this address was also the argument used by EXECUTE. > Thus in PolyForth tick served a dual function. Very neat. > > When Forth-83 came out tick referenced a different address - the > "compilation address". To supply the missing functionality they added > a conversion word >BODY. The assumption being that going from > compilation address to parameter field address was a simple translation. This was particularly annoying since in the first of the two meetings that developed Forth83 the group voted for ' to return the PFA, and at the second voted to change it to the CFA, despite the fact that FORTH, Inc. and other implementors had, in good faith, implemented the first requirement. FORTH, Inc. elected not to change (having just completed an extensive product upgrade intended to be Forth83 compliant), so polyFORTH was never entirely Forth83-compatible as regards this and a few other issues. > By Forth-94 all bets were off. Compilation address became "execution > token" and >BODY was relegated to CREATEd words. That was partly an attempt to arrive at a compromise to resolve the issue, by allowing systems to retain whatever practice they preferred in regard to what ' returned. However, there was a more important issue: in the days of Forth83, the content of most definitions was specified, including the content of colon definitions. Everything used 16-bit cells, and colon definitions contained addresses of words. The decision to allow other implementation strategies, in the interest of improved performance and other benefits, rendered the content of most words completely implementation-dependent. As a result, the definition of an xt (something returned by ' or ['] and consumed by EXECUTE) and the limitations on >BODY (to words defined by CREATE) became necessary. > So now we come full circle and Forth implementations are again looking > at a parsing word like the old tick which can return the parameter field > address of objects. > > How weird is that. I still don't see how it could be useful without constraining the content of objects. Cheers, Elizabeth -- ================================================== Elizabeth D. Rather (US & Canada) 800-55-FORTH FORTH Inc. +1 310.999.6784 5959 West Century Blvd. Suite 700 Los Angeles, CA 90045 http://www.forth.com "Forth-based products and Services for real-time applications since 1973." ==================================================
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Can i rely on >BODY for anything at all? Zbiggy <zbigniew2011REMOVE@gmail.REMOVE.com> - 2013-03-20 01:03 +0000
Re: Can i rely on >BODY for anything at all? Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-20 02:18 +0100
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-20 13:58 +1100
Re: Can i rely on >BODY for anything at all? Mark Wills <markrobertwills@yahoo.co.uk> - 2013-03-19 23:59 -0700
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-21 23:17 +1100
Re: Can i rely on >BODY for anything at all? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-21 07:27 -0500
Re: Can i rely on >BODY for anything at all? Sieur de Bienville <morrimichael@gmail.com> - 2013-03-21 07:01 -0700
Re: Can i rely on >BODY for anything at all? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-21 09:14 -0500
DEFER@ (was: Can i rely on >BODY for anything at all?) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-21 17:31 +0000
Re: Can i rely on >BODY for anything at all? Sieur de Bienville <morrimichael@gmail.com> - 2013-03-22 14:30 -0700
Re: Can i rely on >BODY for anything at all? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-23 05:34 -0500
Re: Can i rely on >BODY for anything at all? Brad Eckert <hwfwguy@gmail.com> - 2013-03-25 09:44 -0700
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-22 01:30 +1100
Re: Can i rely on >BODY for anything at all? Alex McDonald <blog@rivadpm.com> - 2013-03-21 08:17 -0700
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-22 12:14 +1100
Re: Can i rely on >BODY for anything at all? Alex McDonald <blog@rivadpm.com> - 2013-03-22 03:33 -0700
Re: Can i rely on >BODY for anything at all? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-21 15:15 -0500
Re: Can i rely on >BODY for anything at all? Coos Haak <chforth@hccnet.nl> - 2013-03-22 00:24 +0100
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-22 11:49 +1100
Re: Can i rely on >BODY for anything at all? Alex McDonald <blog@rivadpm.com> - 2013-03-22 04:22 -0700
Re: Can i rely on >BODY for anything at all? Coos Haak <chforth@hccnet.nl> - 2013-03-22 22:38 +0100
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-23 21:37 +1100
Re: Can i rely on >BODY for anything at all? Alex McDonald <blog@rivadpm.com> - 2013-03-23 05:06 -0700
Re: Can i rely on >BODY for anything at all? Coos Haak <chforth@hccnet.nl> - 2013-03-23 13:18 +0100
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-24 00:17 +1100
Re: Can i rely on >BODY for anything at all? Coos Haak <chforth@hccnet.nl> - 2013-03-23 15:10 +0100
Re: Can i rely on >BODY for anything at all? Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-24 01:25 +0100
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-26 12:55 +1100
Re: Can i rely on >BODY for anything at all? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-26 05:51 -0500
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-28 23:31 +1100
Re: Can i rely on >BODY for anything at all? stephenXXX@mpeforth.com (Stephen Pelc) - 2013-03-28 12:57 +0000
Re: Can i rely on >BODY for anything at all? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-28 08:15 -0500
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-30 12:56 +1100
Re: Can i rely on >BODY for anything at all? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-30 04:56 -0500
Re: Can i rely on >BODY for anything at all? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-30 10:32 +0000
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-04-04 12:36 +1000
Re: Can i rely on >BODY for anything at all? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-28 17:39 +0000
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-28 21:32 +1100
Re: Can i rely on >BODY for anything at all? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-03-28 11:58 +0000
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-29 00:59 +1100
Re: Can i rely on >BODY for anything at all? "Elizabeth D. Rather" <erather@forth.com> - 2013-03-28 08:41 -1000
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-30 12:43 +1100
Re: Can i rely on >BODY for anything at all? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-27 17:15 +0000
Re: Can i rely on >BODY for anything at all? Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-27 22:04 +0100
Re: Can i rely on >BODY for anything at all? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-28 12:17 +0000
Re: Can i rely on >BODY for anything at all? "Ed" <invalid@nospam.com> - 2013-03-26 13:13 +1100
Re: Can i rely on >BODY for anything at all? Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-24 01:21 +0100
Re: Can i rely on >BODY for anything at all? Mark Wills <markrobertwills@yahoo.co.uk> - 2013-03-20 00:01 -0700
Re: Can i rely on >BODY for anything at all? "Elizabeth D. Rather" <erather@forth.com> - 2013-03-19 22:02 -1000
Re: Can i rely on >BODY for anything at all? "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-03-20 05:27 -0400
Re: Can i rely on >BODY for anything at all? Zbiggy <zbigniew2011REMOVE@gmail.REMOVE.com> - 2013-03-20 10:27 +0000
Re: Can i rely on >BODY for anything at all? Mark Wills <markrobertwills@yahoo.co.uk> - 2013-03-20 03:23 -0700
Re: Can i rely on >BODY for anything at all? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-03-20 17:22 +0000
Re: Can i rely on >BODY for anything at all? "Elizabeth D. Rather" <erather@forth.com> - 2013-03-20 07:52 -1000
Re: Can i rely on >BODY for anything at all? Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2013-03-20 18:56 +0000
OT: SF-translations Zbiggy <zbigniew2011REMOVE@gmail.REMOVE.com> - 2013-03-20 21:44 +0000
Re: OT: SF-translations Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-20 23:12 +0100
Re: OT: SF-translations Zbiggy <zbigniew2011REMOVE@gmail.REMOVE.com> - 2013-03-20 22:45 +0000
Re: OT: SF-translations Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-21 15:50 +0100
Re: OT: SF-translations "Elizabeth D. Rather" <erather@forth.com> - 2013-03-20 12:38 -1000
Re: Can i rely on >BODY for anything at all? "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-03-21 05:52 -0400
Re: Can i rely on >BODY for anything at all? Zbiggy <zbigniew2011REMOVE@gmail.REMOVE.com> - 2013-03-21 10:08 +0000
Re: Can i rely on >BODY for anything at all? "Elizabeth D. Rather" <erather@forth.com> - 2013-03-21 08:17 -1000
Re: Can i rely on >BODY for anything at all? Zbiggy <zbigniew2011REMOVE@gmail.REMOVE.com> - 2013-03-21 18:46 +0000
Re: Can i rely on >BODY for anything at all? mhx@iae.nl (Marcel Hendrix) - 2013-03-21 20:20 +0200
Re: Can i rely on >BODY for anything at all? Brad Eckert <hwfwguy@gmail.com> - 2013-03-22 08:41 -0700
Re: Can i rely on >BODY for anything at all? m.a.m.hendrix@tue.nl - 2013-03-22 09:03 -0700
Re: Can i rely on >BODY for anything at all? "Elizabeth D. Rather" <erather@forth.com> - 2013-03-22 08:05 -1000
Re: Can i rely on >BODY for anything at all? Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-22 22:17 +0100
Re: Can i rely on >BODY for anything at all? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-23 12:07 +0000
Re: Can i rely on >BODY for anything at all? Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-24 01:40 +0100
Re: Can i rely on >BODY for anything at all? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-24 03:55 -0500
Re: Can i rely on >BODY for anything at all? stephenXXX@mpeforth.com (Stephen Pelc) - 2013-03-24 12:18 +0000
Re: Can i rely on >BODY for anything at all? Alex McDonald <blog@rivadpm.com> - 2013-03-24 06:04 -0700
Re: Can i rely on >BODY for anything at all? Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-24 15:31 +0100
Re: Can i rely on >BODY for anything at all? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-03-23 02:26 +0000
Re: Can i rely on >BODY for anything at all? "Elizabeth D. Rather" <erather@forth.com> - 2013-03-22 17:39 -1000
Re: Can i rely on >BODY for anything at all? Coos Haak <chforth@hccnet.nl> - 2013-03-20 19:18 +0100
Re: Can i rely on >BODY for anything at all? Zbiggy <zbigniew2011REMOVE@gmail.REMOVE.com> - 2013-03-21 16:18 +0000
Re: Can i rely on >BODY for anything at all? Coos Haak <chforth@hccnet.nl> - 2013-03-22 00:34 +0100
Re: Can i rely on >BODY for anything at all? Zbiggy <zbigniew2011REMOVE@gmail.REMOVE.com> - 2013-03-21 23:54 +0000
Re: Can i rely on >BODY for anything at all? Coos Haak <chforth@hccnet.nl> - 2013-03-22 00:54 +0100
Re: Can i rely on >BODY for anything at all? "Elizabeth D. Rather" <erather@forth.com> - 2013-03-21 14:37 -1000
Re: Can i rely on >BODY for anything at all? Alex McDonald <blog@rivadpm.com> - 2013-03-20 04:48 -0700
Re: Can i rely on >BODY for anything at all? "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-03-21 05:43 -0400
Re: Can i rely on >BODY for anything at all? Alex McDonald <blog@rivadpm.com> - 2013-03-21 08:30 -0700
Re: Can i rely on >BODY for anything at all? "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-03-22 03:31 -0400
Re: Can i rely on >BODY for anything at all? "Elizabeth D. Rather" <erather@forth.com> - 2013-03-21 22:07 -1000
Re: Can i rely on >BODY for anything at all? Alex McDonald <blog@rivadpm.com> - 2013-03-22 03:37 -0700
Re: Can i rely on >BODY for anything at all? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-03-20 17:14 +0000
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