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From: zenith-steven@cs.yale.edu (Steven Ericsson Zenith)
Newsgroups: comp.lang.misc
Subject: Re: comparison: was He's not the only one at it again!
Message-ID: <25696@cs.yale.edu>
Date: 31 Jul 90 20:25:30 GMT
References: <25630@cs.yale.edu> <58091@lanl.gov> <3478@goanna.cs.rmit.oz.au> <25681@cs.yale.edu> <3261@stl.stc.co.uk>
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In article <3261@stl.stc.co.uk>, tom@nw.stl.stc.co.uk (Tom Thomson) writes:
|>In article <25681@cs.yale.edu> zenith-steven@cs.yale.edu (Steven
Ericsson Zenith) writes:
|>>
|>>a := b	means "assign the value of b to a".
|>>a = b	means "a is equal to b".
|>>
|>>The use of := distinguishes assignment from equality, thus prevents
|>>overloading a single operator and IMHO is a much nicer solution to the
|>>C hack == used to ovecome the same problem.
|>
|>I'm not sure what Steven is claiming here.
|> 
|>Is he claiming that ":=" vs "=" is a greater visual distinction than "=" vs
|>".EQ."?

You are right to observe that my claim is ambiguous. I'll repeat here
what I have been saying in email, and have posted here before.

My intent was to point out that the equality symbol is widely used
with a quite distinct meaning in general (outside of Computer
Science): a = b meaning "a is equal to b" as opposed to a := b which
is untainted by any other meaning that I know of. I would argue that use of the
former to express the meaning of the latter is counter intuitive -
given the broad use of = in common usage across the world. So to
define = as assignment is rather like defining a language with the
symbol GO to mean output - it's almost there but is misleading.

My posting was terse and it wasn't meant to imply ignorance on the
part of the original posters. My apologies to them.

--                        
Steven Ericsson Zenith              *            email: zenith@cs.yale.edu
Fax: (203) 466 2768                 |            voice: (203) 432 1278
"The tower should warn the people not to believe in it." - P.D.Ouspensky
Yale University Dept of Computer Science 51 Prospect St New Haven CT 06520 USA