Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.lang.forth > #38848

Re: SET-COMPILER

From "Alex McDonald" <blog@rivadpm.com>
Newsgroups comp.lang.forth
Subject Re: SET-COMPILER
Date 2015-05-05 22:03 +0100
Organization A noiseless patient Spider
Message-ID <mibb5p$ibh$1@dont-email.me> (permalink)
References (3 earlier) <2015May2.134148@mips.complang.tuwien.ac.at> <5544c837$0$21329$e4fe514c@dreader37.news.xs4all.nl> <2015May2.190034@mips.complang.tuwien.ac.at> <mi4sm2$rvg$1@dont-email.me> <01dd1f51-fe2b-495c-9068-fa0eecee511f@googlegroups.com>

Show all headers | View raw


on 03/05/2015 15:30:31, JennyB wrote:
> On Sunday, 3 May 2015 11:19:46 UTC+1, Alex McDonald  wrote:
>> on 02/05/2015 18:00:34, Anton wrote:
>> > That is why recognizers are better than parsing words like
>> > S"; no STATE-smartness or SET-COMPILER problems.
>>
>> From EuroForth 2014: "Recognizers: Matthias Trute is working on an RfD".
>> Did it eever get written? I've looked on the Forth RfDs and not seen it.
> 
> http://amforth.sourceforge.net/pr/Recognizer-rfc.pdf
> Recognizers offer a way to respond to different patterns, such as a
> prefix for alternative number formats. When they match, they return
> <something> (probably) on the stack, and a key to how to interpret,
> compile or postpone it. They are kinda-sorta like wordlists, and we've
> had some discussion as to how or whether they should be part of the
> Search Order.
> 
> Although recognizers can deal with many patterns, the most common and
> easie st to decode is a fixed prefix followed by variable text. Then,
> for exampl e, you can write "HELLO WORLD" instead of S" HELLO WORLD",
> so it is a poss ible replacement for dual words.
> 
> You obviously can't tick a pattern, but it does make sense to POSTPONE
> it, because all the parsing is done at compile time, which makes
> compiler macro s a bit neater. ]] lions tigers bears "Oh My!" type [[
> 
> With a well-behaved POSTPONE S" , on the other hand, the parsing would
> take place when the macro was executed.
> 

I've reviewed the recognizer RfD and my first reaction is that it's too
complex and too prescriptive.

Win32Forth and my derivative use the following method; from the doc (note
that chain is a singly linked list of XTs to be executed in sequence).

<quote>
"Each number conversion routine on the "number?-chain" chain is sent a
string ( addr len) and can attempt to convert the number. If the
conversion fails the routine performs a -1 THROW to indicate that it
can't convert the string; the next routine is then tried until success or
the chain is exhausted. If the chain is exhausted, then a -13 THROW
(undefined) is executed.

[Historical note] Earlier versions of Win32Forth used a similar chain
technique, but carried a flag that was checked to see if the preceding
routine had succesfully done the conversion. Performing a THROW on
failure is much easier since it can be issued regardless of stack
oontents as it automaticaly tidies up the stack before returning."
</quote>

The downsides of this are:

(a) The exception wordset is required

(b) It returns only a cell, two cells or a float with an appropriate flag
(but this may be all that's needed)

(b) It's a list of recognizers rather than a stack (but that can be
rectified quite simply)

However, it is simple, it is easy to implement new recognizers, and it
has proved enormously flexible. It also supports MOPS-like object:method
syntaxes. Windows has many constants. A recognizer provides lookup of
constants in a provided DLL. Words such as WM_MOVE are resolved
"automagically" so that they can be used without having to declare them
as CONSTANT.

I think the proposed system also introduces a number of new problems.

(a) There is no proposal for what might be meant by POSTPONE 42 and other
tokens (and it doesn't discuss it, but also what is meant by ' 42).

(b) It introduces three XTs to deal with the recognised token:
XT-INTERPRET XT-COMPILE XT-POSTPONE. This requires STATE in the
interpreter, and causes extra complexity in dual XT systems where
compilation vs interpretation is based on a programmatically maintained
state rather than a tested variable.

Back to comp.lang.forth | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread


Thread

SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-04-27 01:34 -0700
  Re: SET-COMPILER stephen@mpeforth.com (Stephen Pelc) - 2015-04-27 14:52 +0000
    Re: SET-COMPILER Bernd Paysan <bernd.paysan@gmx.de> - 2015-04-27 21:17 +0200
    Re: SET-COMPILER hughaguilar96@gmail.com - 2015-04-28 09:41 -0700
  Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-04-27 16:53 +0100
    Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-04-27 17:02 +0100
      Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-04-27 10:23 -0700
    Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-04-27 10:02 -0700
      Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-01 17:15 +0000
        Re: SET-COMPILER Bernd Paysan <bernd.paysan@gmx.de> - 2015-05-01 23:38 +0200
  Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-04-27 14:52 +0000
    Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-04-27 17:09 +0100
      Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-04-27 16:54 +0000
        Re: SET-COMPILER stephen@mpeforth.com (Stephen Pelc) - 2015-04-28 09:11 +0000
          Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-04-28 04:28 -0700
            Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-04-29 13:49 -0700
              Re: SET-COMPILER Bernd Paysan <bernd.paysan@gmx.de> - 2015-04-30 00:13 +0200
              Re: SET-COMPILER stephen@mpeforth.com (Stephen Pelc) - 2015-04-30 06:32 +0000
                Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-04-30 05:22 -0700
                Re: SET-COMPILER stephen@mpeforth.com (Stephen Pelc) - 2015-04-30 15:27 +0000
                Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-04-30 19:16 +0100
                Re: SET-COMPILER stephen@mpeforth.com (Stephen Pelc) - 2015-04-30 21:08 +0000
                Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-04-30 23:05 +0100
                Re: SET-COMPILER hughaguilar96@gmail.com - 2015-04-30 15:47 -0700
                Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-01 12:29 +0100
                Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-02 15:25 +0000
                Re: SET-COMPILER hughaguilar96@gmail.com - 2015-04-30 17:07 -0700
                Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-05-01 02:40 -0700
                Re: SET-COMPILER stephen@mpeforth.com (Stephen Pelc) - 2015-05-01 10:24 +0000
                Re: SET-COMPILER Bernd Paysan <bernd.paysan@gmx.de> - 2015-05-01 22:55 +0200
                Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-05-02 01:32 -0700
                Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-02 16:27 +0000
                Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-05-03 08:36 -0700
                Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-04 16:44 +0000
                Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-02 15:37 +0000
                Re: SET-COMPILER Bernd Paysan <bernd.paysan@gmx.de> - 2015-05-01 01:33 +0200
                Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-05-01 03:15 -0700
                Re: SET-COMPILER albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-01 12:47 +0000
                Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-05-01 10:29 -0700
                Re: SET-COMPILER albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-01 20:32 +0000
                Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-02 15:51 +0000
                Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-02 15:29 +0000
                Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-02 14:59 +0000
              Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-04 16:11 +0000
          Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-02 12:04 +0000
    Re: SET-COMPILER Bernd Paysan <bernd.paysan@gmx.de> - 2015-04-28 03:22 +0200
      Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-02 11:09 +0000
        Re: SET-COMPILER albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-02 12:30 +0000
          Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-02 16:58 +0000
        Re: SET-COMPILER Bernd Paysan <bernd.paysan@gmx.de> - 2015-05-02 20:42 +0200
          Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-04 16:28 +0000
          Re: SET-COMPILER Mark Wills <markwills1970@gmail.com> - 2015-05-06 04:14 -0700
    Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-04-27 23:57 -0700
      Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-02 11:41 +0000
        Re: SET-COMPILER albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-02 12:51 +0000
          Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-02 17:00 +0000
            Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-03 11:19 +0100
              Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-05-03 07:30 -0700
                Re: SET-COMPILER Coos Haak <chforth@hccnet.nl> - 2015-05-03 21:45 +0200
                Re: SET-COMPILER Coos Haak <chforth@hccnet.nl> - 2015-05-03 21:48 +0200
                Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-05 22:03 +0100
                Re: SET-COMPILER albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-05 22:56 +0000
                PREFIX JennyB <jennybrien@googlemail.com> - 2015-05-06 02:30 -0700
                Re: PREFIX anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-06 12:23 +0000
                Re: PREFIX "Alex McDonald" <blog@rivadpm.com> - 2015-05-06 16:44 +0100
                Re: PREFIX anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-06 16:03 +0000
                Re: PREFIX "Alex McDonald" <blog@rivadpm.com> - 2015-05-06 17:40 +0100
                Re: PREFIX albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-06 19:44 +0000
                Re: PREFIX Bernd Paysan <bernd.paysan@gmx.de> - 2015-05-06 22:05 +0200
                Re: PREFIX Bernd Linsel <bl1@gmx.com> - 2015-05-07 04:23 +0200
                Re: PREFIX anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-08 11:48 +0000
                Re: PREFIX anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-08 12:04 +0000
                Re: PREFIX anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-08 11:55 +0000
                Re: PREFIX "Alex McDonald" <blog@rivadpm.com> - 2015-05-06 14:20 +0100
                Re: PREFIX albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-06 19:41 +0000
                Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-06 12:29 +0000
                Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-06 15:07 +0100
                Re: SET-COMPILER Matthias Trute <matthias.trute@gmail.com> - 2015-05-09 03:02 -0700
                Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-09 17:23 +0100
                Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-11 08:07 +0100
                Re: Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-11 11:20 +0100
                Re: Recognizer RfD was Re: SET-COMPILER Matthias Trute <matthias.trute@gmail.com> - 2015-05-12 10:05 -0700
                Re: Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-12 18:34 +0100
                Re: Recognizer RfD was Re: SET-COMPILER Matthias Trute <matthias.trute@gmail.com> - 2015-05-12 12:07 -0700
                Re: Recognizer RfD was Re: SET-COMPILER Bernd Paysan <bernd.paysan@gmx.de> - 2015-05-12 22:11 +0200
                Re: Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-12 21:35 +0100
                Re: Recognizer RfD was Re: SET-COMPILER Bernd Paysan <bernd.paysan@gmx.de> - 2015-05-13 01:31 +0200
                Re: Recognizer RfD was Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-13 16:20 +0000
                Re: Recognizer RfD was Re: SET-COMPILER Matthias Trute <matthias.trute@gmail.com> - 2015-05-13 12:20 -0700
                Re: Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-13 22:24 +0100
                Re: Recognizer RfD was Re: SET-COMPILER albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-14 11:26 +0000
                Re: Recognizer RfD was Re: SET-COMPILER Matthias Trute <matthias.trute@gmail.com> - 2015-05-14 11:00 -0700
                Re: Recognizer RfD was Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-05-14 08:06 -0700
                Re: Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-14 17:21 +0100
                Re: Recognizer RfD was Re: SET-COMPILER Matthias Trute <matthias.trute@gmail.com> - 2015-05-14 11:31 -0700
                Re: Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-14 19:41 +0100
                Re: Recognizer RfD was Re: SET-COMPILER Matthias Trute <matthias.trute@gmail.com> - 2015-05-14 11:49 -0700
                Re: Recognizer RfD was Re: SET-COMPILER albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-15 09:41 +0000
                Re: Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-15 12:19 +0100
                Re: Recognizer RfD was Re: SET-COMPILER albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-15 14:42 +0000
                Re: Recognizer RfD was Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-05-15 10:37 -0700
                Re: Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-15 23:00 +0100
                Re: Recognizer RfD was Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-16 13:52 +0000
                Re: Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-16 19:24 +0100
                Re: Recognizer RfD was Re: SET-COMPILER Matthias Trute <matthias.trute@gmail.com> - 2015-05-16 13:26 -0700
                Re: Recognizer RfD was Re: SET-COMPILER Coos Haak <chforth@hccnet.nl> - 2015-05-17 00:27 +0200
                Re: Recognizer RfD was Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-17 10:03 +0000
                Re: Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-17 23:25 +0100
                Re: Recognizer RfD was Re: SET-COMPILER albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-15 10:02 +0000
                Re: Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-15 12:35 +0100
                Re: Recognizer RfD was Re: SET-COMPILER albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-15 15:33 +0000
                Re: Recognizer RfD was Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-15 14:01 +0000
                Re: Recognizer RfD was Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-15 13:14 +0000
                Re: Recognizer RfD was Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-13 17:07 +0000
                Re: Recognizer RfD was Re: SET-COMPILER Bernd Paysan <bernd.paysan@gmx.de> - 2015-05-14 03:27 +0200
                Re: Recognizer RfD was Re: SET-COMPILER hughaguilar96@gmail.com - 2015-05-13 19:23 -0700
                Re: Recognizer RfD was Re: SET-COMPILER JennyB <jennybrien@googlemail.com> - 2015-05-14 01:08 -0700
                Re: Recognizer RfD was Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-13 14:30 +0000
                Re: Recognizer RfD was Re: SET-COMPILER Bernd Paysan <bernd.paysan@gmx.de> - 2015-05-14 03:40 +0200
                Re: Recognizer RfD was Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-15 13:26 +0000
                Re: Recognizer RfD was Re: SET-COMPILER "Alex McDonald" <blog@rivadpm.com> - 2015-05-12 21:33 +0100
                Re: Recognizer RfD was Re: SET-COMPILER albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-05-13 10:36 +0000
                Re: Recognizer RfD was Re: SET-COMPILER anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2015-05-13 16:06 +0000
              Re: SET-COMPILER Bernd Paysan <bernd.paysan@gmx.de> - 2015-05-03 20:38 +0200

csiph-web