swap() macro (LISP & Algol)

[Joseph S. D. Yao]

I'm surprised nobody seems to know this.

LISP 2.0 [1] is a child of mating LISP 1.5 with ALGOL 60.

I was sure there were some MIT/SDC folk reading this.	;-)

[1] Sammet, Jean, _Programming_Languages:_History_and_Fundamentals_.
    Prentice-Hall, Inc., New Jersey, 1969.
-- 

	Joe Yao		hadron!jsdy at seismo.{CSS.GOV,ARPA,UUCP}
			jsdy at hadron.COM (not yet domainised)