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From: DAVID@PENNDRLS.BITNET
Newsgroups: comp.lang.forth
Subject: Postfixer FORTH
Message-ID: <9008152018.AA23733@ucbvax.Berkeley.EDU>
Date: 15 Aug 90 15:13:41 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Reply-To: DAVID%PENNDRLS.BITNET@SCFVM.GSFC.NASA.GOV
Organization: The Internet
Lines: 46

How about this for a more postfix FORTH syntax:

" SomeWord" Is 20 Constant
" *2"       Is : 2 * ;

'Is' factors out Create without changing the compiler significantly.
The Name field still gets laid down first.  Defining words then
lay down a Code field at the current location, which is
conveniently right where it should go.

Another idea I've been fooling with arose from a previous discussion
of Vocabularies as string recognizers.  The argument was to enlarge
the scope of Number by implementing Vocabularies as generalized string
recognizers, with most of them doing it through table lookup in the
dictionary, but Number and similar routines doing it alogorithmically.
For instance, you could allow "x" to be recognized as a character
constant just as 5 is recognized as a numerical constant.

So, how about a recognizer that is a mixture?  Suppose we have a word
that recognizes tokens of the form 'Something' as being a reference
to the CFA of the word Something?  The Interpreter would leave the
CFA on the stack, the Compiler would compile it as a litteral.  We
could then say

  Defer FooBar
  'Fred' 'FooBar' Is
  : FooFred   'Fred' 'FooBar' Is ;

(to use Is in its more common meaning).  I think this is much
prettier.  And more postfix.

Once started down this path, though, you start to get into a lot of
delimited strings.  For instance, "Something" could be Something as a
string constant, <Something> could be the Body address of Something,
and [Something] could Compile Something even if Something is Immediate.
I'm not sure I want to go that far, but .  .  .

  "Fred"     Is Immediate : Fred's Action ;
  "CompFred" Is : Some Extra [Fred] Actions ;
  "FooBar"   Is Defered
  "FooFred"  Is : 'Fred' <FooBar> ! ;

Now for the Big Question.  Would this still be FORTH?  I think it
would be.  But it would *not* be Chuck Moore Forth, or ANS FORTH.

-- R. David Murray    (DAVID@PENNDRLS.BITNET, DAVID@PENNDRLS.UPENN.EDU)