Revival de Medley/Interlisp: Arme élégante pour une ère plus civilisée aiguisée de nouveau

ANTIQUE CODE SHOW Xerox’s pioneering graphical Lisp workstation operating system is not only alive, well, and MIT-licensed, but running in the cloud as well as on modern OSes. Last week, the British Computer Society hosted a talk about the the Medley Interlisp Restoration Project by Steve Kaisler of George Washington University, who literally wrote the book on Interlisp. The Medley Interlisp project team is headed up by Larry M Masinter, Nick Briggs, and Ron Kaplan*. Medley is a bit more than just a programming language, or even a nonstandard dialect of Lisp, though, but to try to convey its significance, we need to delve into history a little. When a computer company goes out of business, or withdraws from a market and discontinues the software it built, it’s quite common to hear calls for that software to be open sourced and made available to the world. Very occasionally, it even happens. Unfortunately, when it does, the usual result is that everyone totally ignores it: learning to navigate a substantial codebase and then trying to modernize it so that it can be run on newer hardware, and maybe even be useful again, is a massive undertaking. So nobody does it, and it quietly mouds away, ignored and unloved, until it’s of no conceivable use to anyone. That’s pretty much what happened to Perihelion’s massively parallel cluster OS Helios, for instance. But not always.