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From: wmb@MITCH.ENG.SUN.COM
Newsgroups: comp.lang.forth
Subject: Interpret/compile consistency
Message-ID: <9009220119.AA14290@ucbvax.Berkeley.EDU>
Date: 22 Sep 90 00:05:15 GMT
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Reply-To: wmb%MITCH.ENG.SUN.COM@SCFVM.GSFC.NASA.GOV
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>   Just curious.
>   Does something like [ IF THEN ] work?

Yes

>   What about?   [ IF [ IF THEN ] THEN ]
>   How about?   IF [ : ... ; ] THEN
>   Or?   IF [ : ... [ : ... ; ] ... ; ] THEN    8^)

No


I was interested in making interpreted control structures work correctly,
within the context of otherwise-traditional Forth usage.

Nested brackets, and colon definitions nested within control structures,
are outside the scope of what I was trying to accomplish.  In order to
support nested brackets/colon-definitions, one must dispense with the
traditional notion of STATE as a global variable.  (Defining new and
better interpretations of Forth operators is fun and I have done my
share of it in private, but I had a much less ambitious, and thus
more likely achievable, goal in this case.)


> You got a paper out of that!?

Sure, why not?  I did not claim to be the first person to have invented
such a scheme (in fact I cited several examples of "prior art").  I was
simply reminding implementors who may not have thought of it (and there
are many of them) that it is very easy and inexpensive to do (and I showed
them how), so why aren't they doing it?

Papers do not have to be earth-shattering.  If they did, the Forth
literature would be pretty sparse.


Forth to the Future,
Mitch Bradley, wmb@Eng.Sun.COM