Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!van-bc!ubc-cs!alberta!calgary!cpsc!gintera
From: gintera@cpsc.ucalgary.ca (Andrew Ginter)
Newsgroups: comp.lang.forth
Subject: Re: Thoughts on Forth (was: Why don't people use Forth...)
Summary: function nesting
Message-ID: <2342@cs-spool.calgary.UUCP>
Date: 15 Jan 90 18:19:08 GMT
References: <6001@sdcc6.ucsd.edu> <756@noe.UUCP> <95.UUL1.3#5129@willett.UUCP> <240.UUL1.3#5129@willett.UUCP>
Sender: news@calgary.UUCP
Lines: 35

It seems to me I've argued this argument before, but last time it was
about LISP and its derivatives.  Now granted, people use LISP and
FORTH for almost completely different kinds of applications and LISP
is incredibly much slower than FORTH.  What is similar about the
languages, though, is their expressive power.  Language lovers of both
species claim that software is easier and quicker to develop in their
favorite language than in mainstream languages.  Actually, seems that
language lovers of ALL species claim this...

Anyhow - my point is that extensibility and regular syntax are nice,
yes.  But the key to the claim that you need to write less code in
these languages is the degree of function nesting.  Extremely compact
applications in both LISP and FORTH (and maybe APL? - I'm not that
familiar with the language) employ high degrees of function nesting.
The results of functions are passed directly as arguments to other
functions whose results are passed to other functions, etc.

MOST programmers will grant that deep nesting produces compact code
and that such code is comparatively easy to write.  They will also
argue that deeply nested code is difficult to read and understand - a
criticism commonly leveled against LISP and FORTH.  SOME programmers
(FORTH lovers included) have no difficulty with function nesting and
don't understand why the rest of the world doesn't like the obvious
advantagers of FORTH:

  * clean syntax
  * super extensibility
  * compact, easy to write code
  * good speed & small size (which FORTH has and LISP usually doesn't)

The fact is that MOST people have trouble with nesting and no matter
how you tout a language which encourages nesting, they will never
like it.

Andrew Ginter, 403-282-2984, gintera@CPSC.UCALGARY.CA, Ginter@UNCAMULT.BITNET