Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!rutgers!att!pacbell.com!ucsd!sdcc6!ir230
From: ir230@sdcc6.ucsd.edu (john wavrik)
Newsgroups: comp.lang.forth
Subject: Re: What makes Forth Forth
Message-ID: <14813@sdcc6.ucsd.edu>
Date: 8 Dec 90 18:04:05 GMT
References: <9012051459.AA18739@ucbvax.Berkeley.EDU> <12692@medusa.cs.purdue.edu> <68713@unix.cis.pitt.edu>
Organization: University of California, San Diego
Lines: 74



Doug Philips writes:

#>                               I *DO* see an objection -- and I 
#>regard a strength of Forth as the ability to add new objects with 
#>first class status. This ability comes from the fact that the Forth 
#>programmer has access to the language at the level at which primary 
#>objects are introduced...
#
# Well, what do you say to the C++/Ada/Smalltalk people then.  They can
# certainly do that too.

I'd say: "I guess you find the ability to create first class data 
objects in your language just as powerful a tool as I find it in 
mine." 

#>P.S.  The main challenge to the Forth community is to show that 
#>      putting more control over the language in the hands of the 
#>      programmer can result in more power without drastically 
#>      increasing error or increasing the incidence of incompre-
#>      hensible programs. 
#
# I have seen nothing so far that would enable me to distinguish 
# PostScript from Forth.  In fact, the power and popularity of 
# PostScript would seem to have proved the point already. 

I must be missing something: what point has been proved?
The popularity of Postscript is not the topic being discussed.

# Even CM's own characterization of the essentials of Forth would 
# apply to PostScript and Fifth.  (I seem to recall them from a 
# transcript of talk/speech CM gave that was reprinted in Volume one 
# of FD, if I can find it I'll extract more details). 

I think Charles Moore would be the first to tell you that he has 
said many things at many times (usually in 25 words or less). It 
was he, by the way, who started the discussion at Asilomar.

I don't want to put words in Moore's mouth -- but I think you will 
find that Forth was NOT created by developing a theory of what 
characteristics a language should have, then making the language 
fit the theory. Moore instead seemed to follow his instincts in 
making design decisions as the language evolved. The result is 
that the language assumed an identity of its own that even its 
creator stands back and studies. Its a bit like the relationship 
of a parent to a child.  

Forth fits applications well that weren't imagined when the 
language was conceived. Many design decision fit together in such 
a way that Forth performs brilliantly (for some people) -- almost 
defying the law of computer science gravity. The aim is to get 
people who have had this experience with Forth to spend some time 
trying to identify the factors responsible. There are two serious 
purposes for wanting this done: 

1.  If a move is made to gain acceptance for the language in an
    academic arena several things are needed -- among them the 
    ability to discuss the language in the way that other computer 
    languages are discussed.
    
2.  If we, collectively, are going to alter the language -- 
    redefining it, adding new attributes and eliminating others, 
    the standard advice applies: "If you don't understand it then 
    don't mess with it".
    
    (The problem with the advice, of course, is that some of 
    the people who are messing with it may not realize that they 
    don't understand it!) 

                                                  John J Wavrik 
             jjwavrik@ucsd.edu                    Dept of Math  C-012 
                                                  Univ of Calif - San Diego 
                                                  La Jolla, CA  92093