Editing Interlisp

{{Short description|Dialect of the Lisp programming language}}
{{Infobox programming language
| name = Interlisp
| logo = <!-- Filename only -->
| logo caption = 
| screenshot = <!-- Filename only -->
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| paradigms = [[Multiparadigm programming language|Multiparadigm]]: [[Functional programming|functional]], [[Procedural programming|procedural]], [[Object-oriented programming|object-oriented]], [[Declarative programming|declarative]], [[Reflective programming|reflective]], [[Metaprogramming|meta]]
| family = [[Lisp (programming language)|Lisp]]
| designer = <!-- or: | designers = -->
| developer = <!-- or: | developers = -->
| released = {{Start date and age|1968}}
| latest release version = Medley 2.0
| latest release date = {{Start date and age|1992|02}}
| latest preview version = 
| latest preview date = <!-- {{Start date and age|YYYY|MM|DD|df=yes/no}} -->
| typing = 
| scope = 
| programming language = [[C (programming language)|C]]
| discontinued = Yes
| platform = [[PDP-10]], [[MOS Technology 6502]], [[Atari 8-bit]]; Xerox 1100, 1108, 1109, 1186, 1132
| operating system = [[TENEX (operating system)|TENEX]], [[TOPS-20]]
| license = [[Proprietary software|Proprietary]]
| file ext = 
| file format = <!-- or: | file formats = -->
| website = <!-- {{URL|www.example.com}} -->
| implementations = 
| dialects = 
| influenced by = [[Lisp (programming language)|Lisp]], [[BBN LISP]]
| influenced = [[Lisp Machine Lisp]]
}}
'''Interlisp''' (also seen with a variety of capitalizations) is a programming environment built around a version of the programming language [[Lisp (programming language)|Lisp]]. Interlisp development began in 1966 at Bolt, Beranek and Newman (renamed [[BBN Technologies]]) in [[Cambridge, Massachusetts]] with Lisp implemented for the [[Digital Equipment Corporation]] (DEC) [[PDP-1]] computer by [[Daniel G. Bobrow|Danny Bobrow]] and D. L. Murphy. In 1970, [[Alice K. Hartley]] implemented [[BBN LISP]], which ran on [[PDP-10]] machines running the [[operating system]] [[TENEX (operating system)|TENEX]] (renamed [[TOPS-20]]). In 1973,<ref>{{cite web |url=https://interlisp.org/docs/IRM.pdf |title=Interlisp Reference Manual |date=1993 }}</ref> when [[Daniel G. Bobrow|Danny Bobrow]], [[Warren Teitelman]] and [[Ronald Kaplan]] moved from BBN to the Xerox Palo Alto Research Center ([[PARC (company)|PARC]]), it was renamed Interlisp. Interlisp became a popular Lisp development tool for [[artificial intelligence]] (AI) researchers at [[Stanford University]] and elsewhere in the [[Community of practice|community]] of the Defense Advanced Research Projects Agency ([[DARPA]]). Interlisp was notable for integrating interactive development tools into an [[integrated development environment]] (IDE), such as a [[debugger]], an automatic correction tool for simple errors (via do what I mean ([[DWIM]]) software design),<ref>{{cite journal |last=Teitelman |first=Warren |date=April 1972 |title="Do What I Mean": the programmer's assistant |journal=Computers and Automation |pages=8–11 }}</ref> and analysis tools.

==Adaptations==
At Xerox PARC, an early attempt was made to define a [[virtual machine]] to facilitate [[porting]], termed the ''Interlisp virtual machine''. However, it was not useful as a basis for porting.

[[L. Peter Deutsch|Peter Deutsch]] defined a byte-coded instruction set for Interlisp, and implemented it as a [[microcode]] emulator for the [[Xerox Alto]]. This was then ported to a series of workstation designs produced by [[Xerox]] for internal use and for commercial exploitation, including on the Xerox 1100 (Dolphin), 1108 (Dandelion), 1109 (the floating-point enabled Dandetiger), [[Xerox Daybreak|1186 (Daybreak)]], and 1132 (Dorado). Interlisp implementations for these were known collectively as Interlisp-D. Commercially, these were sold as [[Lisp machine]]s and branded as Xerox AI Workstations when [[Larry Masinter]] was the chief scientist of that group. The same designs, but with different software, were also sold under different names (e.g., when running the Viewpoint system, the 1186 Daybreak was sold as the Xerox 6085.) Releases of Interlisp-D were named according to a musical theme, which ended with Koto, Lyric, and Medley. Later versions included an implementation of pre-[[American National Standards Institute]] (ANSI) [[Common Lisp]], named Xerox Common Lisp. LOOPS, the object system for Interlisp-D, became, along with [[Symbolics]]' [[Flavors (programming language)|Flavors]] system, the basis for the [[Common Lisp Object System]] (CLOS).

In 1974, [[DARPA]] awarded a contract to the [[University of California, San Diego]] (UCSD) to implement Interlisp on the [[Burroughs large systems|Burroughs B6700]].  The motivation was the larger virtual memory addressing space afforded by the B6700 architecture compared to the PDP-10.  However, by the time the software was released (1975), the PDP-10's address space had been increased, and Interlisp-10 remained the standard of the day for AI research.  The implementors were Bill Gord and Stan Sieler, with guidance from [[Daniel Bobrow]], and under the overall management of [[Kenneth Bowles|Dr. Ken Bowles]].  UCSD Interlisp included a compiler which emitted "p-code", which was could be intermixed with standard LISP code during interpretation.  This p-code appears to have preceded [[UCSD Pascal]] p-code by a year or two.

The PDP-10 version of Interlisp became ''Interlisp-10''; BBN had an internal project to build ''Interlisp-Jericho'' and there was a 1982 port to [[Berkeley Software Distribution]] (BSD) [[Unix]] on the [[VAX]] by [[Stanford University]], [[Information Sciences Institute]] (ISI) and Xerox PARC, called ''Interlisp-VAX''.<ref>{{cite report
|title=Interlisp-VAX: A Report
|last=Masinter |first=Larry M.
|url=http://www.softwarepreservation.org/projects/LISP/interlisp/Interlisp-VAX_A_Report.pdf
|year=1981
|publisher=Stanford University
}}</ref>

In 1981, Warren Teitelman and [[Larry Masinter]] published a paper on Interlisp in [[IEEE Computer]] providing an overview of the system and its design philosophy, setting starts used for the platform.<ref>{{cite journal |last1=Teitelman |first1=Warren |last2=Masinter |first2=Larry M. |date=April 1981 |title=The Interlisp Programming Environment |url=http://larry.masinter.net/interlisp-ieee.pdf |journal=IEEE Computer |volume=14 |issue=4 |pages=25–33 |doi=10.1109/C-M.1981.220410 |s2cid=13447494 }}</ref>

Also in 1981, a variant for the [[MOS Technology 6502]] processor, INTER-LISP/65, was released by [[Datasoft]] for the [[Atari 8-bit computers]]. In 1985 to 1987, a team from [[Fuji Xerox]] developed an implementation of the microcoded [[bytecode]] [[Interpreter (computing)|interpreter]] in the language [[C (programming language)|C]], and, together with Xerox AI Systems (XAIS) in [[Sunnyvale, California]], completed the port of the environment and emulator to the [[Sun Microsystems]] [[SPARC]] 4 architecture. In 1987, XAIS was [[Corporate spin-off|spun off]] into Envos Corporation, which failed almost immediately.

Interlisp-D release timeline:

* 1983 – Chorus
* 1983 – Fugue
* June 1984 – Carol
* January 1985 – Harmony
* 1985 – Intermezzo
* December 1985 – Koto, first release to support the Xerox 1185/1186 workstation, some support for Common Lisp
* June 1987 – Lyric, supports Xerox Common Lisp as part of the standard Lisp sysout
* September 1988 – Medley, for Xerox 1100 and Sun 3 machines
* February 1992 – Medley 2.0, includes CLOS with MOP, runs on various Unix machines, [[DOS]] 4.0, and the Xerox 1186<ref>{{cite web |url=https://www.cs.cmu.edu/Groups/AI/html/faqs/lang/lisp/part4/faq-doc-2.html |title=Lisp FAQ, Commercial Common Lisp Implementations }}</ref>

{{Lisp}}

In 1992, an [[Association for Computing Machinery]] (ACM) [[Software System Award]] recognized the team of [[Daniel G. Bobrow]], Richard R. Burton, [[L. Peter Deutsch]], [[Ronald Kaplan]], [[Larry Masinter]], [[Warren Teitelman]] for their pioneering work on Interlisp.

==Revitalization==
The Medley Interlisp source code and the source code for the virtual machine emulator have both been open-sourced by the [https://interlisp.org/ Medley Interlisp Project]. The system runs on modern hardware/operating systems.

==See also==
* [[Lisp machine]]

==References==
{{Reflist}}

==Publications==
*[[Warren Teitelman]] ''et al.'', ''Interlisp Reference Manual'' (Xerox tech report, 1974)
*[[J Strother Moore]], ''The Interlisp Virtual Machine Specification'' (Xerox tech report, 1976)
*[[L. Peter Deutsch|L Peter Deutsch]], ''A LISP Machine with Very Compact Programs'' (Third Joint Conference on Artificial Intelligence, 1973).
* Kaisler, S. H. 1986 Interlisp: the Language and its Usage. Wiley-Interscience.

== External links ==
* [http://bitsavers.org/pdf/xerox/interlisp/ Archived Interlisp documentation at bitsavers.org]
* [https://github.com/blakemcbride/LISPF4 LISPF4] an Interlisp interpreter written originally in [[Fortran]] by Mats Nordstrom and ported to [[C (programming language)|C]] ([[Microsoft Windows|Windows]], [[Macintosh operating systems|Mac OS]], and [[Linux]]) by Blake McBride.
* [http://www.softwarepreservation.org/projects/LISP/interlisp Interlisp documentation at Computer History Museum].
* [http://www.atariage.com/forums/topic/116093-datasoft-inter-lisp65/ AtariAge forum discussion on INTER-LISP/65]
* [http://wiki.strotmann.de/wiki/Wiki.jsp?page=Lisp AtariWiki entry for INTER-LISP/65] {{Webarchive|url=https://web.archive.org/web/20130502051337/http://wiki.strotmann.de/wiki/Wiki.jsp?page=Lisp |date=2013-05-02 }}
* [https://interlisp.org/ Medley Interlisp Project]
* [https://github.com/Interlisp Medley Interlisp source code repository]

{{Lisp programming language}}

[[Category:Lisp (programming language)]]
[[Category:Dynamic programming languages]]
[[Category:Functional languages]]
[[Category:Lisp programming language family]]
[[Category:Lisp (programming language)-based operating systems]]
[[Category:Programming languages created in 1968]]