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From: scc@cl.cam.ac.uk (Stephen Crawley)
Newsgroups: comp.object
Subject: Re: object-oriented this, that, and the other thing
Message-ID: <1673@gannet.cl.cam.ac.uk>
Date: 27 Nov 89 00:16:17 GMT
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Organization: U of Cambridge Comp Lab, UK
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Dave Berry writes:
[... stuff deleted ...]

> My opinion is that the main feature of an OO language is that objects
> contain information about their class.  The effect of this is that we
> can build collections of objects of different classes, call a member
> function of an arbitrary object of that collection and get the correct
> function for that class.  In other words, dynamic binding of functions
> (as opposed to dynamic binding of variables, as in old lisps).

[...]

> So my definition of an OO language would be
> "classes + dynamic binding of functions".
> with the footnote that inheritance is required for this in statically 
> typed languages and damn useful anyway in dynamically typed ones.

GRRRR ...

I wish people would stick to the well established definitions of terms
like "object-oriented" and not go around inventing new & incompatible 
ones for no good reason!

.. GRRRR

Dave Berry is just plain wrong.  First, inheritence does not give
dynamic binding in a static language; inheritence + virtual operations
gives dynamic binding!  Second, Dave's new "definition" of OO excludes
languages that are currently recognised as OO according to the accepted
definitions.

> Of course, I'm probably wrong ...

You said it!!!

-- Steve