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March 24, 1986 Electronic Engineering Times article
I believe this is a reasonably accurate transcription of the article.
From the March 24, 1986 Electronic Engineering Times:
Object-Oriented Extension to Lisp Language Offered
By Tom J. Schwartz
ANDOVER, Mass. -- The first object-oriented extension of the AI language
CommonLisp will be shipped this week. LMI Machine Inc.'s ObjectLisp
allows generic operations to be performed on modular units, called
LMI Machines has gotten the jump on Xerox Corp. (El Segundo, CA), which
had promised to deliver a similar language, CommonLoops, by August (see
EE Times, Aug. 26, Page 1). Xerox hasn't shipped, so LMI Machines broke
out of the gate with ObjectLisp. However, Xerox is in beta test with
CommonLisp users now have to build their own object-oriented extensions.
And yet, there's no universal standard on how to write Lisp code to deal
A cogent example of ObjectLisp applies to the military. Objects might
include friendly and hostile fighter planes, helicopters, and missiles.
Computer simulations of these objects can be grouped into generic types
-- moving objects. Characteristics of moving objects can be identified
as fighters, helicopters, and missiles.
LMI's object-oriented programming incoporates a unique function: It's
able to pass messages among these objects. ObjectLisp offers a mature
object-oriented dialogue. And it uses syntax consistent with
CommonLisp. The message-passing function is akin to the concept of its
SmallTalk was introduced in the 1970s at Xerox Corp.'s Palo Alto
Research Center, and it incorporated the method of representing modular
units or objects.
"ObjectLisp does not distinguish among classes and instances," said LMI
president Robert Moore, "and provides the user with a powerful and very
flexible semantic base."
CommonLisp has become the only common denominator among all Lisp
dialects that enables users to pass programs to each other.
In The Beginning
Four years ago, a group of AI innovators conceived CommonLisp as a
minimal implementation of the first symbolic programming language.
Thirty years ago, John McCarthy began work on Lisp at MIT.
The language acquired many dialects as it matured. They were needed to
meet widely varying expectations. Eventually, the DoD and university
researchers suggested that the proliferation of dialects should stop.
CMU and an informal ad hoc committee of Lisp researchers undertook to
create a universal software standard. They did it in less than four
years. Almost the entire AI community supports CommonLisp. And IBM
reportedly has solicited bids on development of a Lisp dialect that
could merge its VM Lisp with CommonLisp.
"The time was right for CommonLisp and the ad hoc committee made the
difference," said Patrick Winston, director of MIT's AI lab. He's the
author of a book entitled 'Lisp'. "If the IEEE had become involved, it
could have taken another twenty years to get a Lisp standard," he added.
Industry response to these proposals has been mixed. Dr. Raj Reddy,
director of the Robotics Institute at CMU said, "In the case of these
object-oriented extensions, we don't have the twenty years of experience
we had in Lisp. I think it may be too early to try to formulate a
Lucid Makes Vision Clear
Lucid Inc. Chairman Tony Slocum disagreed. "We have a clear vision of
what symbolic computing should be," he said. "I think these companies
are doing the right thing. People should put forth what they believe
"The marketplace and the community will focus in and form an accepted
standard," he added.
Lucid (Menlo Park, CA) manufactures a fast CommonLisp which runs on many
LMI intends to maintain ObjectLisp in portable form. This would enable
it to run on many machines and under a number of CommonLisp
These include: Sun 2 and 3 workstations, which run Sun CommonLisp from
Lucid; the IBM PC AT, which runs Gold Hill Golden CommonLisp; DEC's
VAX/VMS, running NIL; DEC's MicroVAX, running DEC CommonLisp; the
Silicon Graphics Workstation, running Franz Inc.'s CommonLisp; and
Symbolics 3600 CommonLisp.
The source code and specification of CommonLisp is avaialble free from
LMI. But there's a media charge of $195.