Re: Date's First Great Blunder

From: Alfredo Novoa <>
Date: 14 Apr 2004 06:27:41 -0700
Message-ID: <>

"Dawn M. Wolthuis" <> wrote in message news:<c5ia56$t04$>...

> He suggests that there are two answers given: domain = object class or
> relvar = object class. He then says that the first equation is obviously
> right and the second wrong. Classes are types and domains are types, but
> relvars are variables and, therefore, not types, so QED.

It's all very obvious.

> The idea, it seems, is to rid Java programmers of the notion of using
> classes to define "relations" or records.

The idea is to rid programmers of making great blunders.

> I'm guessing I'm not the only one
> who doesn't buy Mr. Date's argument.

The vast majority of the OO coders reject the evident when it is against the dogma.

> I'll toss out one of the way-too-many-thoughts buzzing in my head on this
> topic. How about this equation:
> Class = Metadata
> A class is a spec/template -- not a variable nor an object. There can be
> metadata for a type and metadata for a relation/record and classes
> corresponding to either.

A class is a type and "object" is the mix and confusion of the "variable" and "value" concepts.

Metadata is data like any other data, and it should be represented in the form of relations.

> Do many folks agree with Date on this point or is this one of his
> lone-ranger attempts to push against the OO folks?

This is an attempt to educate the misleaded and misinformed practicioners.

  Alfredo Received on Wed Apr 14 2004 - 15:27:41 CEST

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