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From: ted@imsvax.UUCP (Ted Holden)
Newsgroups: net.micro.pc,net.lang
Subject: Things left out of Borland's Prolog
Message-ID: <636@imsvax.UUCP>
Date: Tue, 4-Nov-86 22:35:38 EST
Article-I.D.: imsvax.636
Posted: Tue Nov  4 22:35:38 1986
Date-Received: Wed, 5-Nov-86 22:45:27 EST
Organization: IMS Inc, Rockville MD
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Xref: mnetor net.micro.pc:7540 net.lang:1279



There's a paragraph in the September issue of Dobbs Journal which I can't
get over:

    "Perhaps the greatest shortcoming of Turbo Prolog as an implementation
    of Prolog is the lack of what might be called "metalinguistic" functions
    and operators.  Some of these supplied in Prolog are arg, functor, name,
    op, clause, and call and the univ operator.  In general, these functions
    allow the Prolog program to examine itself, to operate on code as data,
    and to construct new clauses and goals undreampt of by the programmer."

Now, I don't TRUST my own computer or any of IMS's computers enough to
let them try to program themselves.... no telling what they might try
to do.   Can anyone out there give me an example of a legitimate use
for such a technique, preferably one which could not be achieved with
more ordinary kinds of programming skills and languages?   Any opinions
as to whether Kahn left these things out of Turbo Prolog because he
thought they were dangerous or whether he's just being lazy?

Ted Holden
IMS