Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site harvard.ARPA
Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!ihnp4!houxm!whuxl!whuxlm!harpo!decvax!genrad!panda!talcott!harvard!macrakis
From: macrakis@harvard.ARPA (Stavros Macrakis)
Newsgroups: net.ai
Subject: Standardization on Ada
Message-ID: <394@harvard.ARPA>
Date: Thu, 21-Feb-85 12:13:10 EST
Article-I.D.: harvard.394
Posted: Thu Feb 21 12:13:10 1985
Date-Received: Tue, 26-Feb-85 07:17:27 EST
References: <417@ssc-vax.UUCP> <301@panda.UUCP> <6982@watdaisy.UUCP> <676@topaz.ARPA>
Distribution: net
Organization: Aiken Comp. Lab., Harvard
Lines: 32

> 	There are many...[DoD] directives.  The Ada directive mostly
> applies to "embedded systems", [namely] operating systems, compilers,...

Embedded computer systems (ECS), actually, are computers which are an
integral part of a larger operational system.  This means computers inside
tanks, radars, cameras, and microwave ovens....  Compilers are rarely found
inside ECS's.

> 	For AI research, expert systems, command and control systems
> using AI techniques, etc. the language of DoD choice is Common Lisp. ...
>		R Mark Chilenskas decvax!genrad!panda!rmc

The Ada directive says nothing at all about research, only operational systems.

> > There is an escape clause [allowing] languages to be used for special
> > applications where there is good reason....  At the Common Lisp
> > conference it was said that the ARPA Strategic Computing project would
> > [use] Common Lisp.
> I think that far too much emphasis has been placed on the need for LISP
> in AI work. -- DJSolomon@watdaisy

Be that as it may (and I think you're mostly right), I wonder to what
extent Lisp will be used in operational systems even if prototypes are
built in Lisp.  As a hard-core ECS programmer once told me, you can't
afford a stack overflow during your aircraft carrier landing (which means
they calculate maximum stack size ahead of time, or alteratively use only
static storage (!)), much less a free storage overflow....

I suspect that if Lisp programs (AI or not) make it into the embedded
world, they will be either nonessential programs or will have been
re-analyzed and quite likely re-programmed anyway: the Lisp version will be
used as a prototype.
	-s