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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Subject: Re: status of Ada STL?
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Date: Tue, 18 Jun 2002 15:21:19 GMT
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18k11tm001@sneakemail.com (Russ) writes:

> I heard that ":=" was originally chosen by some early language
> designer (can't remember who) who actually wanted to use "<=", but his
> ancient ancient keyboard didn't have "<".

I believe the language you're thinking of was Algol-60, and I believe
they wanted to use a left-pointing arrow (a single character, not a "<"
followed by an "="), which character sets didn't support, so they
searched for some other notation that indicated the asymmetric nature of
assignment, and came up with ":=".

It's sad that ancient character sets didn't have the proper symbols for
"<=", ">=", and "/=".

>... You've fooled yourself into
> thinking it has some deep meaning.

It *does* have a deep meaning, or at least some meaning more substantial
than the stated rationale for C, which involves number of keystrokes:
assignment is asymmetric (the left-hand side is very different from the
right), and ":=" indicates that reasonably well.  Assignment does not
mean the same thing as equality.

>... Einstein said, "Everything should
> be made as simple as possible, but not simpler." So Einstein agrees
> with me.

Einstein was happy to obey hundreds of years of maths tradition as to
the meaning of "=".  ;-)

Anyway, saying that "=" is simpler than ":=" seems silly to me.
Do we measure simplicity by the length of the symbol?

- Bob