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From: blickstein@speedy.DEC (Dave Blickstein)
Newsgroups: net.lang.apl
Subject: Programming idiom
Message-ID: <607@decwrl.UUCP>
Date: Sun, 17-Feb-85 14:10:00 EST
Article-I.D.: decwrl.607
Posted: Sun Feb 17 14:10:00 1985
Date-Received: Tue, 19-Feb-85 06:53:47 EST
Sender: daemon@decwrl.UUCP
Organization: DEC Engineering Network
Lines: 16

Gee, I think any dedicated idiom freak would never use the example you gave to
exchange two values.   A much more "idiomatic" idiom for exchanging two
values A and B is

	A = A XOR B;
	B = B XOR A;		/* If you don't think this works
	A = A XOR B;		   write out a truth table        */

Note that this version has the additional advantage of not requiring
a temporary.

    Dave Blickstein

    (UUCP)  {allegra|decvax|ihnp4|ucbvax}!decwrl!dec-rhea!dec-orphan!blickstein

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