The XLISP family

XLISP is a family of multi-platform LISP implementations, they comprise of a Scheme compatible interpreter (bytecode compiler for versions 3 and higher) called XLISP originally written by David Betz and he added few object oriented features to the basic Scheme language. The core runtime is written in C while the rest is implemented in XLISP itself and the program was released in to the public domain up until about version 2.1 where the license was changed. XLISP 2.1 is also the last version of the original XLISP package to be available in an OS/2 port.

The program was first released in 1983 as eXperimental LISP and was at the time a generic small LISP subset that was not Scheme compatible. Various versions of the package are used in open source projects externally or internally as scripting engines, it is also the basis for the LISP that is used as an internat scripting engine by Autocad (AutoLISP).

XLISP-PLUS

Tom Almy had ported Xlisp to OS/2 and DOS and added a Microsoft Windows and Linux version, with Xlisp 2.1 he forked the program and introduced his own version called XLISP-PLUS. It is not known if the fork was due to the licence change introduced with version 2.1 or if it is due to Almy's interest in getting more Common Lisp features working on the Xlisp system, but the original author resisted adding anything but an object system to the base Scheme specification.

XLISP-PLUS adds a host of Common Lisp features to Xlisp but also adds a huge amount of bug fixes, however changes to the original Xlisp such as the bytecode compiler that was introduced with version 3 have not been integrated in this fork. The maintainer stopped updating XLISP-PLUS in 1999 when CLisp was taken over by the Free Software Foundation since the maintainer believed that with the frequent CLisp updates, Xlisp would become "unnecessary". However, after 16 years of inactivity, Mr Almy suddenly kicked into life in early 2016 and created a new 3.05 version of XLISP-PLUS for MS Windows, Linux and Mac OSX, while neither the DOS not the OS/2 version got an update the libraries will function with the 3.04 OS/2 version, and he has also created a new Windows 3.x 16 bit version that will work under OS/2.

XLISP-STAT

A fork of XLISP 2.1 with statistical additions, originally developed for the Apple Macintosh in the 1980's but later ported to MS Windows and most UNIX systems and a number of additional packages that add to the system are available although development of both the package and the add-ons has slowed down considerably in the last few years.

XLISP-STAT modifies some of the standard Lisp mathematical functions for to allow them to operate on lists and arrays of numbers and add some basic statistical and plot functions, including histograms, scatterplots, 3-dimensional rotatable plots and scatterplot matrices most of which are interactive to a degree.

WINTERP

WINTERP is a derivative of XLISP-PLUS 2.1 that adds widget support for UNIX like operating systems that have the Motif widget library installed.

Versions

XLISP-PLUS

• XLISP-PLUS v3.04 (1999-01-09)

Last known OS/2 version, note that the differences between 3.04 and 3.05 for other systems are primarily in the LISP portion of the code and if you download the xl305req.zip file from the XLISP-PLUS homepage you can run that version with the 3.04 version for OS/2.

• XLISP-PLUS v3.05 (2016-02-19)
• XLISP-PLUS v2.1gce (1998-05-28) - Last known Palm Pilot version.

XLISP

• XLISP v0.0 (1983)
• XLISP v1.0 (1983)
• XLISP v1.4 (1985)
• XLISP v2.0 (1989)
• XLISP v2.1 (1991)
• XLISP v3 (1997 - some trivial bug fixes in 1998 and 2002)

Only released in a version for Microsoft Windows

WINTERP

• WINTERP 2.10 (2008) - Last known version.

Note that WINTERP release numbers are not synchronised with XLISP-PLUS, the 2.1 release is similar to a XP version 3.04 rather than the classic XP 2.1.

XLISP-STAT

• XLISP-STAT v 3.52.23 (2013-03-20) - Last known version

Note that XLISP-STAT release numbers are not synchronised with XLISP

Links

• XLisp-Plus v2.1 (1995/12/27)
• XLISP-Plus Homepage
• XLISP Homepage
• Current XLISP-STAT file reprisotory
• Original XLISP-STAT file reprisotory
• Dr. Luca Scrucca's XLSIP-STAT page - Outdated but contains a number of small add on packages XS and ARC.
• ViSta - the Visual Statistics System - Add on for XLISP-STAT
• XLISP for Classic MAC OS/Finder
• XLISP Functions
• An archive of very early XLISP versions including 0.0 and 1.0

Publications

• Bonnie J. Fladung: The XLISP Primer - 1987 - Prentice Hall - ISBN 0139720847
• Ernst D. Schmitter: Praktische Einführung in LISP. - 1987 - Hofacker - ISBN 3-88963-229-7
• Tim I Mikkelsen: XLISP 2.0 LANGUAGE REFERENCE - 1989
• Tim I Mikkelsen: XLISP 2.0 OBJECTS PRIMER - 1990
• Jeff Prothero: xlisp 2.1 internals - 1991

XLISP-STAT

• Applied Regression Including Computing and Graphics 2nd - 1999 - John Wiley & Sons - ISBN 0-471-31711-X

Note that the homepage also contains a software package that runs on XLISP-STAT called ARC

• Luke Tierney: LISP-STAT: An Object-Oriented Environment for Statistical Computing and Dynamic Graphics - 1990 - Wiley - ISBN 978-0-471-50916-5
• Jan de Leeuw: On Abandoning XLISP-STAT - 2005 - In PDF format.

Licence and availability

• Open source software
• Xlisp version 2.1 and later are released under the Four Clause BSD Licence, versions prior to that are in the public domain.
• XLISP-PLUS in mainly in the public domain, however a few of the included LISP library files have a no commercial usage clause.
• XLISP-STAT is licensed under the One Clause BSD Licence

Author

• David Betz - Original Xlisp author
• Tom Almy Original porter of XLISP to OS/2, maintainer of XLISP-PLUS
• Luke Tierney - XLISP-STAT