Re: Another recognizer discussion

From	anton@mips.complang.tuwien.ac.at (Anton Ertl)
Newsgroups	comp.lang.forth
Subject	Re: Another recognizer discussion
Date	2017-06-16 07:35 +0000
Organization	Institut fuer Computersprachen, Technische Universitaet Wien
Message-ID	<2017Jun16.093513@mips.complang.tuwien.ac.at> (permalink)
References	(5 earlier) <2017Jun13.172153@mips.complang.tuwien.ac.at> <e3fd170d-0d83-4c6c-b1cc-3a7c53685c60@googlegroups.com> <2017Jun14.121916@mips.complang.tuwien.ac.at> <1fd1be0d-2209-483d-87c3-21480041d54e@googlegroups.com> <59413e41.596775007@news.eternal-september.org>

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stephen@mpeforth.com (Stephen Pelc) writes:
>There's an important point of philosophy
>and/or design here, which is that the XT was *intended* to be
>the single point of contact with a word - the XT is all you need.

You may believe that repeating this again and again will make it true.
It doesn't.

>Most systems optimise XTs for EXECUTE
>but there's no requirement for this to be so.

There is certainly a requirement: The requirement is called
"performance".  0.5% of all executed primitives in
<https://www.complang.tuwien.ac.at/forth/peep/sorted> are EXECUTE, so
making EXECUTE slower has a small, but significant influence on
performance.  Of course, if other requirements are more important, we
may decide not to satisfy this requirement, but I have yet to see a
more important requirement.

>While an XT is an opaque type (system dependent) there
>is no point in trying to impose meaning on it.

If an XT had no meaning, we would not need it.  The meaning is the
operations we can use on it: EXECUTE COMPILE, >BODY DEFER@ DEFER!.  So
its meaning is that it represents an EXECUTEable thing, and if that
thing is associated with data, a way to access the data.

> Adding NT, a second
>opaque type for the same thing, is verging on the absurd.

The NT is not for the same thing.  The NT is for named words; you can
get the name string of the word out of it, the interpretation
semantics and the compilation semantics of the named word.

Sure, if there was a 1:1 correspondence between named words and
EXECUTEable things, we could use the same token for both purposes, but
there isn't, thanks to :NONAME, SYNONYM and having several xts
associated with a name (e.g., for S").

On Monday I heard a talk about code obfuscation.  One of the
techniques used for that is to combine several opaque types into one,
with a combined set of fields and operations.  Normally one would call
that bad factoring or bad design, because it makes the code harder to
understand (and therefore also harder to maintain), but in code
obfuscation that is the point.

>In this discussion, it is perfectly appropriate to suggest that Gforth
>should enhance the functionality of its XTs.

From you that surprises me, because in the past you were very keen on
not prescribing implementation, and wielded words like
"disenfrenchize" in such discussions.  I am happy to read that you
will no longer be doing that.

I am happy to discuss any such suggestions, but I have yet to see
them.

- 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 2017: http://www.euroforth.org/ef17/

Thread

Another recognizer discussion Alex <alex@rivadpm.com> - 2017-05-29 20:47 +0100
  Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-05-29 20:57 +0100
    Re: Another recognizer discussion peter.m.falth@gmail.com - 2017-05-29 13:18 -0700
      Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-05-29 22:47 +0100
      Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-30 07:43 +0000
    Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-30 07:30 +0000
    Re: Another recognizer discussion albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-30 09:53 +0200
    Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-05-30 22:02 +0100
      Re: Another recognizer discussion peter.m.falth@gmail.com - 2017-05-31 01:27 -0700
        Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-05-31 15:12 +0100
      Re: Another recognizer discussion minforth@arcor.de - 2017-05-31 03:43 -0700
        Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-05-31 15:03 +0100
        Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-31 16:46 +0000
      Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-31 11:28 +0000
        Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-31 12:17 +0000
        Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-05-31 15:10 +0100
          Re: Another recognizer discussion mhx@iae.nl - 2017-05-31 11:01 -0700
          Re: Another recognizer discussion stephen@mpeforth.com (Stephen Pelc) - 2017-05-31 22:55 +0000
            Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-01 05:50 +0000
              Re: Another recognizer discussion minforth@arcor.de - 2017-05-31 23:57 -0700
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-01 09:08 +0000
                Re: Another recognizer discussion minforth@arcor.de - 2017-06-01 03:33 -0700
              Re: Another recognizer discussion stephen@mpeforth.com (Stephen Pelc) - 2017-06-01 09:05 +0000
                Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-06-01 15:05 +0100
                Re: Another recognizer discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-06-01 10:05 -0500
                Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-06-01 16:32 +0100
                Re: Another recognizer discussion Brad Eckert <hwfwguy@gmail.com> - 2017-06-01 09:31 -0700
                Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-06-01 19:00 +0100
                Re: Another recognizer discussion stephen@mpeforth.com (Stephen Pelc) - 2017-06-04 22:56 +0000
                Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-06-05 14:41 +0100
                Re: Another recognizer discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-06-02 03:07 -0500
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-10 16:28 +0000
                Re: Another recognizer discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-06-11 02:14 -0500
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-11 10:55 +0000
                Re: Another recognizer discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-06-12 03:22 -0500
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-13 15:21 +0000
                Re: Another recognizer discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-06-14 04:10 -0500
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-15 10:43 +0000
                Re: Another recognizer discussion Andrew Haley <andrew29@littlepinkcloud.invalid> - 2017-06-15 09:11 -0500
                Re: Another recognizer discussion minforth@arcor.de - 2017-06-14 02:55 -0700
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-14 10:19 +0000
                Re: Another recognizer discussion minforth@arcor.de - 2017-06-14 05:44 -0700
                Re: Another recognizer discussion stephen@mpeforth.com (Stephen Pelc) - 2017-06-14 14:27 +0000
                Re: Another recognizer discussion minforth@arcor.de - 2017-06-14 08:06 -0700
                Re: Another recognizer discussion stephen@mpeforth.com (Stephen Pelc) - 2017-06-14 16:36 +0000
                Re: Another recognizer discussion Brad Eckert <hwfwguy@gmail.com> - 2017-06-15 09:48 -0700
                Re: Another recognizer discussion stephen@mpeforth.com (Stephen Pelc) - 2017-06-15 17:18 +0000
                Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-06-15 18:50 +0100
                Re: Another recognizer discussion stephen@mpeforth.com (Stephen Pelc) - 2017-06-15 19:22 +0000
                Re: Another recognizer discussion minforth@arcor.de - 2017-06-15 13:09 -0700
                Re: Another recognizer discussion Brad Eckert <hwfwguy@gmail.com> - 2017-06-15 13:43 -0700
                Re: Another recognizer discussion Lars Brinkhoff <lars.spam@nocrew.org> - 2017-06-15 22:55 +0200
                Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-06-15 22:20 +0100
                pre-Rfd for smart word definition mechanism (was: Another ...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-16 17:04 +0000
                Re: pre-Rfd for smart word definition mechanism (was: Another ...) stephen@mpeforth.com (Stephen Pelc) - 2017-06-16 21:58 +0000
                Re: pre-Rfd for smart word definition mechanism (was: Another ...) JennyB <jennybrien@googlemail.com> - 2017-06-17 00:26 -0700
                Re: pre-Rfd for smart word definition mechanism (was: Another ...) minforth@arcor.de - 2017-06-17 01:18 -0700
                Re: pre-Rfd for smart word definition mechanism (was: Another ...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-17 15:24 +0000
                Re: pre-Rfd for smart word definition mechanism (was: Another ...) JennyB <jennybrien@googlemail.com> - 2017-06-17 12:29 -0700
                Re: pre-Rfd for smart word definition mechanism (was: Another ...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-18 12:29 +0000
                Re: pre-Rfd for smart word definition mechanism (was: Another ...) albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-06-18 16:47 +0200
                Re: pre-Rfd for smart word definition mechanism (was: Another ...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-17 10:20 +0000
                Re: Another recognizer discussion Brad Eckert <hwfwguy@gmail.com> - 2017-06-15 13:01 -0700
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-16 16:55 +0000
                Re: Another recognizer discussion stephen@mpeforth.com (Stephen Pelc) - 2017-06-16 17:40 +0000
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-16 16:47 +0000
                Re: Another recognizer discussion Brad Eckert <hwfwguy@gmail.com> - 2017-06-15 10:34 -0700
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-17 17:35 +0000
                Re: Another recognizer discussion peter.m.falth@gmail.com - 2017-06-17 15:24 -0700
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-18 12:00 +0000
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-16 12:29 +0000
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-16 07:35 +0000
                Re: Another recognizer discussion stephen@mpeforth.com (Stephen Pelc) - 2017-06-11 10:39 +0000
                Re: Another recognizer discussion Richard Owlett <rowlett@cloud85.net> - 2017-06-11 07:19 -0500
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-13 14:04 +0000
                Re: Another recognizer discussion stephen@mpeforth.com (Stephen Pelc) - 2017-06-14 12:50 +0000
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-15 16:19 +0000
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-02 07:59 +0000
                Re: Another recognizer discussion Lars Brinkhoff <lars.spam@nocrew.org> - 2017-06-02 11:48 +0200
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-02 10:24 +0000
                Re: Another recognizer discussion Lars Brinkhoff <lars.spam@nocrew.org> - 2017-06-02 13:04 +0200
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-02 13:30 +0000
                Re: Another recognizer discussion Lars Brinkhoff <lars.spam@nocrew.org> - 2017-06-02 16:36 +0200
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-02 15:51 +0000
                Re: Another recognizer discussion Lars Brinkhoff <lars.spam@nocrew.org> - 2017-06-02 21:09 +0200
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-01 15:55 +0000
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-01 14:21 +0000
                Re: Another recognizer discussion stephen@mpeforth.com (Stephen Pelc) - 2017-06-04 23:07 +0000
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-10 15:49 +0000
                Re: Another recognizer discussion stephen@mpeforth.com (Stephen Pelc) - 2017-06-11 11:14 +0000
                Re: Another recognizer discussion minforth@arcor.de - 2017-06-11 08:24 -0700
                Re: Another recognizer discussion anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-06-13 15:07 +0000
            Re: Another recognizer discussion Alex <alex@rivadpm.com> - 2017-06-01 12:11 +0100
  Re: Another recognizer discussion Matthias Trute <matthias.trute@gmail.com> - 2017-05-30 11:03 -0700

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