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From: hirchert@uxe.cso.uiuc.edu
Newsgroups: comp.lang.misc
Subject: Re: History of := (was: == vs =)
Message-ID: <51300003@uxe.cso.uiuc.edu>
Date: 21 Jan 88 16:48:00 GMT
References: <2337@haddock.ISC.COM>
Lines: 23
Nf-ID: #R:haddock.ISC.COM:2337:uxe.cso.uiuc.edu:51300003:000:1169
Nf-From: uxe.cso.uiuc.edu!hirchert    Jan 21 10:48:00 1988


>>I find := for assignment to be quite obnoxious.  ... misleading ...
>>In math : is often used for comparison, as in ratios.
>>
>>Cyber folklore around the office has it that := originated in Europe
>>as something that looked similar to [left arrow].
>If they wanted to preserve the appearance, I would expect that "<-" or "<="
>would have been a better choice.  I've always believed that the ":=" (in ALGOL
>and its successors) was taken directly from the identical mathematical symbol.
>Since you find it "misleading", I presume you've never seen the mathematical
>usage of ":="?

I was a math major in college and I can't ever remember seeing := used in a
mathematical rather than computer science context.  In what branch of math
is it used and what does it mean?  If there is a current mathematical usage
of this symbol, are you sure that it didn't derive from the computer usage?
(After all, Algol and its descendants have been around for a long time.)

>Karl W. Z. Heuer (ima!haddock!karl or karl@haddock.isc.com), The Walking Lint
>(Followups to comp.lang.misc; this is not C-related anymore.)

Kurt W. Hirchert
National Center for Supercomputing Applications