Essential properties of current standard Forth

From	anton@mips.complang.tuwien.ac.at (Anton Ertl)
Newsgroups	comp.lang.forth
Subject	Essential properties of current standard Forth
Date	2016-09-15 14:19 +0000
Organization	Institut fuer Computersprachen, Technische Universitaet Wien
Message-ID	<2016Sep15.161930@mips.complang.tuwien.ac.at> (permalink)

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At EuroForth Andrew Read gave an impromptu talk where he suggested a
next-standard effort that would not be shackled by
backwards-compatibility with the current (Forth-83/94/2012) line of
standards.

While there was not that much desire for such an effort in the
audience, the talk got me thinking about what is essential in the
current line of Forth standards and which features of a Forth system
would require such a next-standard effort (if there are people that
want to have a standard for that).

What is not essential:

Of course, there are people (including committee members) who disagree
with some choices made in the standard, but that's a matter of opinion
and not the kind of "essential" I have in mind; In particular, if
people could not find a consensus on a different choice earlier, will
it help to start from scratch?  In at least one case, there actually
has been consensus on taking a different choice than an earlier
standard (standardizing "{:" and making "LOCALS|" obsolescent), so if
that happens, the current standard process can change choices, too,
slowly.  We don't need a from-scratch effort for that.

Another issue is removing features, to achieve some form of
minimalism.  We have a mechanism in the standards process for removing
features (it takes it's time, though), so if the community decided we
really want minimality, and if we actually could find consensus on
what we want in a minimal system, we could go there; in practice, this
will not happen, but that has more to do with there being no consensus
that we want a minimal system and no consensus on what it would look
like.

Another issue is that of names.  While machine Forth calls the
exclusive-or operation OR, I don't consider that an essential feature
of machine Forth.  It would be pretty much the same if Chuck Moore had
chosen to call it XOR.  Conversely, if we wanted to remove inclusive
OR, later add an OR that's a synonym for XOR, and then remove XOR,
this could be done, very slowly, over several standards releases.

Possibly essential:

The syntax difference between machine Forth and Color Forth (color
that indicates how to text-interpret the string) cannot be
accommodated in the current line of standards; while it's just syntax,
it's a change that does not allow a transition period, so it would
make no sense to try to do it in the current line of standards.

Pretty essential:

Statically determined stack depth: Requiring that, as sketched for
PAF, would disallow some standard programs (and a lot of buggy
programs).  I guess we could get there in the current line of
standards, but I don't expect it.

Static type checking: StrongForth did that, but also implemented
overloading (e.g., DUP worked as 2DUP when there was a double on the
TOS).  Static type checking would first require a type system; it
would probably disallow more standard programs, especially if you want
to have a somewhat safe type system; the actual repercussions would
depend on the type system.  Overloading would be even more disruptive,
by a lot.

Data stack items: In the current standards, the data stack item is a
machine word (cell), used as integer, address, or a group of bits and
its interpretation depends on the operation; there are a number of
systems that deviate from this:

Floats: There is one suggestion (and a Russion system that works this
way) to use floats as stack items, with words like + working on
floats, and IIRC addresses represented by NaNs (or maybe by
interpreting the bit pattern as address).  That's pretty far from the
current standard.

Dynamically typed stack items (e.g., Factor, 8th, Oforth, with Factor
also doing static type checking to some extent), with dynamic type
checking in the operations and possible overloading, and possible
automatic memory reclamation.  That's even further from the current
line of standards.  Looking at the number of systems that go that way,
there seems to be quite a bit of interest in that direction, so maybe
that's something where such a standard that's not rooted in the
current line of standards might make sense.  But I guess that the
implementors and users of these systems have to work it out if they
need a standard for that, or if they are happy with the different
systems that they have now.

- 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 2016: http://www.euroforth.org/ef16/

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Essential properties of current standard Forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-15 14:19 +0000
  Re: Essential properties of current standard Forth hughaguilar96@gmail.com - 2016-09-15 17:58 -0700
    Re: Essential properties of current standard Forth tabcomputing@gmail.com - 2016-09-24 18:48 -0700
      Re: Essential properties of current standard Forth hughaguilar96@gmail.com - 2016-09-24 21:47 -0700
        Re: Essential properties of current standard Forth tabcomputing@gmail.com - 2016-09-25 08:11 -0700
          Re: Essential properties of current standard Forth hughaguilar96@gmail.com - 2016-09-25 20:14 -0700
            Re: Essential properties of current standard Forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-09-26 11:12 +0200
              Re: Essential properties of current standard Forth Alex <alex@rivadpm.com> - 2016-09-26 12:16 +0100
                Re: Essential properties of current standard Forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-09-26 14:30 +0200
                Re: Essential properties of current standard Forth Coos Haak <htrofhc@gmail.com> - 2016-09-26 15:10 +0200
                Re: Essential properties of current standard Forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-09-26 16:07 +0200
                Re: Essential properties of current standard Forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-26 13:43 +0000
                Re: Essential properties of current standard Forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-09-26 16:36 +0200
        Re: Essential properties of current standard Forth Rod Pemberton <NoHaveNotOne@zxdehrnyya.cam> - 2016-09-25 15:18 -0400
  Re: Essential properties of current standard Forth anotherreepca@gmail.com - 2016-09-18 09:01 -0700
    Re: Essential properties of current standard Forth Cecil Bayona <cbayona@cbayona.com> - 2016-09-18 11:35 -0500
      Re: Essential properties of current standard Forth minforth@arcor.de - 2016-09-19 03:21 -0700
        Re: Essential properties of current standard Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-09-19 09:49 -0500
          Re: Essential properties of current standard Forth minforth@arcor.de - 2016-09-19 12:38 -0700
            Re: Essential properties of current standard Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-09-20 11:23 -0500
              Re: Essential properties of current standard Forth lawrencedo99@gmail.com - 2016-09-20 12:55 -0700
                Re: Essential properties of current standard Forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-09-21 02:24 +0200
              Re: Essential properties of current standard Forth hughaguilar96@gmail.com - 2016-09-20 14:52 -0700
      Re: Essential properties of current standard Forth JUERGEN <epldfpga@aol.com> - 2016-09-19 10:12 -0700
        Re: Essential properties of current standard Forth Cecil Bayona <cbayona@cbayona.com> - 2016-09-19 12:40 -0500
    Re: Essential properties of current standard Forth stephen@mpeforth.com (Stephen Pelc) - 2016-09-21 10:09 +0000
  Re: Essential properties of current standard Forth albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-09-19 13:29 +0200
    Re: Essential properties of current standard Forth foxaudioresearch@gmail.com - 2016-09-19 07:16 -0700
    Re: Essential properties of current standard Forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-19 17:10 +0000
  Re: Essential properties of current standard Forth humptydumpty <ouatubi@gmail.com> - 2016-09-20 22:43 -0700
    Re: Essential properties of current standard Forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-21 12:39 +0000
      Re: Essential properties of current standard Forth hughaguilar96@gmail.com - 2016-09-22 11:40 -0700
        Re: Essential properties of current standard Forth humptydumpty <ouatubi@gmail.com> - 2016-09-23 09:28 -0700
      Re: Essential properties of current standard Forth humptydumpty <ouatubi@gmail.com> - 2016-09-23 09:19 -0700
  Re: Essential properties of current standard Forth Paul Rubin <no.email@nospam.invalid> - 2016-09-23 20:11 -0700
    Re: Essential properties of current standard Forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-24 10:55 +0000
      Re: Essential properties of current standard Forth Matthias Trute <matthias.trute@gmail.com> - 2016-09-24 11:14 -0700
        Re: Essential properties of current standard Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-09-25 03:01 -0500
          Re: Essential properties of current standard Forth Matthias Trute <matthias.trute@gmail.com> - 2016-09-25 02:21 -0700
            Re: Essential properties of current standard Forth lawrencedo99@gmail.com - 2016-09-25 14:01 -0700
            Re: Essential properties of current standard Forth Paul Rubin <no.email@nospam.invalid> - 2016-09-25 15:04 -0700
              Re: Essential properties of current standard Forth lawrencedo99@gmail.com - 2016-09-25 17:39 -0700
                Re: Essential properties of current standard Forth Paul Rubin <no.email@nospam.invalid> - 2016-09-25 17:56 -0700
              Re: Essential properties of current standard Forth Mikael Nordman <oh2aun@gmail.com> - 2016-09-25 20:34 -0700
                Re: Essential properties of current standard Forth Paul Rubin <no.email@nospam.invalid> - 2016-09-25 22:37 -0700
              Re: Essential properties of current standard Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-09-26 02:34 -0500
                Re: Essential properties of current standard Forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-26 14:04 +0000
                Re: Essential properties of current standard Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-09-26 10:40 -0500
                Re: Essential properties of current standard Forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-28 06:43 +0000
                Re: Essential properties of current standard Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-09-28 04:48 -0500
          Re: Essential properties of current standard Forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-26 14:58 +0000
            Re: Essential properties of current standard Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-09-26 11:02 -0500
              Re: Essential properties of current standard Forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-26 23:28 +0000
                Re: Essential properties of current standard Forth Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-09-27 03:49 -0500
              Re: Essential properties of current standard Forth Alex <alex@rivadpm.com> - 2016-09-27 11:43 +0100
        Standardization (was: Essential properties of current standard Forth) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-26 16:01 +0000
          Re: Standardization (was: Essential properties of current standard Forth) stephen@mpeforth.com (Stephen Pelc) - 2016-09-26 20:06 +0000
            Re: Standardization (was: Essential properties of current standard Forth) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-27 14:49 +0000
              Re: Standardization Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-09-27 11:20 -0500
              Re: Standardization (was: Essential properties of current standard Forth) stephen@mpeforth.com (Stephen Pelc) - 2016-09-28 12:07 +0000
                Re: Standardization (was: Essential properties of current standard Forth) Bernd Paysan <bernd@net2o.de> - 2016-09-29 02:07 +0000
                Re: Standardization (was: Essential properties of current standard Forth) hughaguilar96@gmail.com - 2016-09-28 19:40 -0700
                Re: Standardization (was: Essential properties of current standard Forth) Ilya Tarasov <ilya74.tarasov@gmail.com> - 2016-09-29 15:22 -0700
                Re: Standardization Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-09-29 04:12 -0500
                Re: Standardization (was: Essential properties of current standard Forth) stephen@mpeforth.com (Stephen Pelc) - 2016-09-29 10:15 +0000
                Re: Standardization (was: Essential properties of current standard Forth) Matthias Trute <matthias.trute@gmail.com> - 2016-09-29 10:38 -0700
      Re: Essential properties of current standard Forth trans <transfire@gmail.com> - 2016-09-26 18:04 -0700
        Re: Essential properties of current standard Forth anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-09-27 13:37 +0000
  Re: Essential properties of current standard Forth jim.brakefield@ieee.org - 2016-09-28 13:54 -0700

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