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Jobs. Ritchie. McCarthy. What’s God up to? When do you think it will be out?

The 40th Anniversary of Lisp was 13 years ago. I remember being mostly relieved that the old man didn’t attend my presentation, as it wasn’t really very good. But I’ll remember McCarthy. I haven’t programmed Lisp on a computer in a decade, but I still think in it. About a week ago, I had a sudden urge to play with it again. Here’s the coolest thing I ever wrote in any language, with comments removed. It’s sort of a y-combinator for a fixed-point of three levels of eval/apply.

(defmacro eclipse::WITH-UNIQUE-NAMES (vars &body body)
  `(let ,(loop for var in vars
	       collect `(,var (make-symbol ,(symbol-name var))))
     ,@body))

(defmacro eclipse::REBINDING (vars &body body)
  (loop for var in vars
	for name = (make-symbol (symbol-name var))
	collect `(,name ,var) into renames
	collect ``(,,var ,,name) into temps
	finally (return `(let ,renames
			   (eclipse::with-unique-names ,vars
				`(let (,,@temps)
				   ,,@body))))))

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About Stearns

Howard Stearns works at High Fidelity, Inc., creating the metaverse. Mr. Stearns has a quarter century experience in systems engineering, applications consulting, and management of advanced software technologies. He was the technical lead of University of Wisconsin's Croquet project, an ambitious project convened by computing pioneer Alan Kay to transform collaboration through 3D graphics and real-time, persistent shared spaces. The CAD integration products Mr. Stearns created for expert system pioneer ICAD set the market standard through IPO and acquisition by Oracle. The embedded systems he wrote helped transform the industrial diamond market. In the early 2000s, Mr. Stearns was named Technology Strategist for Curl, the only startup founded by WWW pioneer Tim Berners-Lee. An expert on programming languages and operating systems, Mr. Stearns created the Eclipse commercial Common Lisp programming implementation. Mr. Stearns has two degrees from M.I.T., and has directed family businesses in early childhood education and publishing.

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