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Re: Forth philosophy

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On Thu, 12 Jun 2014 00:58:01 -0400, Elizabeth D. Rather  
<erather@forth.com> wrote:
> On 6/11/14 6:24 PM, rickman wrote:

>> I agree.  Sometimes I wonder if Rod really believes the things he says
>> or if he is just free associating and then working to defend his
>> statement like playing a game of go.
>
> Well, I'm sure the fact that he wrote his Forth in C influenced his
> opinion.

I don't see why.  As I've stated many times to Hugh who doesn't bother
to remember this either, I've not used the classic method of implementing
Forth in C: switch().  My implementation uses ITC with an interpreter
in C.  It's virtually identical to implementing a Forth in assembly.
I.e., if I had implemented it in assembly, it wouldn't be different,
or not much.

> Some of the code he showed us here is pretty tortured, [...]

I think that's a mischaracterization.

First, it's wasn't C code that was posted and "tortured" as I think
you've implied here ...

Second, the one "tortured" Forth example was due to a failed attempt
to relocate a few high-level Forth words to be defined much earlier
in the dictionary.

Once the failed optimization was backed out and removed, the resulting
Forth code was identical to what I had months before.

The failed optimization wouldn't have even been possible if it had
been revealed that my Forth was missing an certain implementation
detail.  The issue for that was discussed in depth here some months
earlier, which you might've considered to be "tortured" too.

> [...] partly because he didn't have Forth programming background [...]

I don't believe that has anything to do with it.  Lack of any serious
documentation on Forth implementation details has been a far bigger
hindrance, IMO.

As you should recall, everything I've implemented passes Hayes core tests
(about 2/3rds), except one: nul terminated strings, which can be fixed
with the addition of a single byte.  I know one of my loop constructs is
broken, but I must leave that for the future.  +LOOP has no way to obtain
an "overflow bit" from C ...  Many of the high-level definitions match
widely available definitions for well known Forth words.  Some of this
was by happenstance, i.e., only one way or one best way or simple, and
others were because I searched c.l.f. for standardized, commonly known,
and widely used definitions for compatibility.  As you may recall, I've
also tested a bunch of Forths for compatibility of functionality on
different issues.

My stack words are a bit odd at the moment because I was defining them
in Forth to reduce C dependence and using some lower-level primitives
to do so.  But, they can be backed out and reverted quickly and in the
future.

> [...] but mostly because of requirements imposed by C.

So far, there are only a few serious issues with C, IMO.  One issue affects
the layout of primitives in the dictionary, but only the primitives since
they're setup in C.  Most of my primitives, currently, are non-Forth words,
but a few are Forth words, so this doesn't generally create any problem.
Another issue restricts what values can be placed in the CFA, i.e., must
call a C function and can't arbitrarily just jump into any Forth word.
Those are the only two serious issues that I recall.


Rod Pemberton

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Thread

Forth philosophy OneArb <o1neeno1@gmail.com> - 2014-06-10 13:23 -0700
  Re: Forth philosophy Roger Levy <roger.levy@gmail.com> - 2014-06-10 14:45 -0700
  Re: Forth philosophy Elizabeth D Rather <erather@forth.com> - 2014-06-10 12:51 -1000
    Re: Forth philosophy hughaguilar96@yahoo.com - 2014-06-10 16:14 -0700
  Re: Forth philosophy Paul E Bennett <Paul_E.Bennett@topmail.co.uk> - 2014-06-11 10:03 +0100
    Re: Forth philosophy visualforth@rocketmail.com - 2014-06-11 11:11 -0700
      Re: Forth philosophy Paul E Bennett <Paul_E.Bennett@topmail.co.uk> - 2014-06-11 21:57 +0100
  Re: Forth philosophy "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-06-11 19:30 -0400
    Re: Forth philosophy "Elizabeth D. Rather" <erather@forth.com> - 2014-06-11 14:26 -1000
      Re: Forth philosophy rickman <gnuarm@gmail.com> - 2014-06-12 00:24 -0400
        Re: Forth philosophy "Elizabeth D. Rather" <erather@forth.com> - 2014-06-11 18:58 -1000
          Re: Forth philosophy "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-06-12 07:33 -0400
            Re: Forth philosophy AKK <akk@nospam.org> - 2014-06-12 20:39 +0200
              Re: Forth philosophy "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-06-12 23:15 -0400
              Re: Forth philosophy anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-06-13 17:29 +0000
                Re: Forth philosophy AKK <akk@nospam.org> - 2014-06-14 12:26 +0200
                Re: Forth philosophy anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-06-14 10:59 +0000
                Re: Forth philosophy Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-06-14 07:39 -0500
                Optimizing C compilers vs. assembly language for Forth interpreters (was: Forth philosophy) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-06-14 14:40 +0000
                Re: Optimizing C compilers vs. assembly language for Forth interpreters Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-06-14 11:25 -0500
                Re: Optimizing C compilers vs. assembly language for Forth interpreters Bernd Paysan <bernd.paysan@gmx.de> - 2014-06-15 23:55 +0200
                Re: Forth philosophy albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-06-14 19:45 +0000
                Re: Forth philosophy Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-06-15 13:18 -0500
                Re: Forth philosophy AKK <akk@nospam.org> - 2014-06-16 21:14 +0200
                Re: Forth philosophy Bernd Paysan <bernd.paysan@gmx.de> - 2014-06-16 22:41 +0200
                Re: Forth philosophy AKK <akk@nospam.org> - 2014-06-17 13:32 +0200
                Re: Forth philosophy Bernd Paysan <bernd.paysan@gmx.de> - 2014-06-17 15:02 +0200
                Re: Forth philosophy mhx@iae.nl - 2014-06-16 13:41 -0700
        Re: Forth philosophy "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-06-12 07:33 -0400
        Re: Forth philosophy barrym95838@yahoo.com - 2014-06-13 21:48 -0700
          Re: Forth philosophy "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-06-14 01:01 -0400
      Re: Forth philosophy Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-06-12 03:02 -0500
      Re: Forth philosophy albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-06-12 10:43 +0000
      Re: Forth philosophy "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-06-12 07:32 -0400

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