Re: object algebra
From: Marshall Spight <mspight_at_dnai.com>
Date: Sat, 28 Feb 2004 23:48:10 GMT
Message-ID: <_M90c.144411$uV3.676780_at_attbi_s51>
> Since the type designer can implement the equality operation any way the
> designer wants, why are the colors necessarily equal?
Date: Sat, 28 Feb 2004 23:48:10 GMT
Message-ID: <_M90c.144411$uV3.676780_at_attbi_s51>
"Bob Badour" <bbadour_at_golden.net> wrote in message news:JMydnSr4AKban9zd4p2dnA_at_golden.net...
>
> Since the type designer can implement the equality operation any way the
> designer wants, why are the colors necessarily equal?
Hmmm. Can the type designer really make equality anything he wants? That seems dangerous to me. Java has this mechanism, and it's error prone.
In a value-oriented world, where variables can only be assigned values and not other variables, I don't see the need for user-defined equality. (I can imagine user-implemented equality for performance reasons, but I would expect such would have the same semantics as system defined equality.)
Marshall Received on Sun Feb 29 2004 - 00:48:10 CET