Re: Clean Object Class Design -- Circle/Ellipse

From: S Perryman <q_at_deja.com>
Date: Mon, 1 Oct 2001 10:51:27 +0100
Message-ID: <9p9ddf$grq8o$1@ID-75294.news.dfncis.de>

"James A. Robertson" <jarober_at_mail.com> wrote in message news:3BB73A9B.6020306_at_mail.com...

> > I find it very telling that almost every OO pundit has found it
necessary to
> > write an apologia explaining why the very real and natural
subtype/supertype
> > relationship between circle and ellipse does not apply in OO.

> I find it telling that you worry about this at all. Go do some system
> development and see how often this problem actually arises.

The "problem" has arisen on virtually every system I've ever worked on using OO
techniques (10+ yrs) . Shame was it took me until last year to finally understand how to
identify/categorise/resolve the problem (ie by seeing the recurring pattern) without
even having to write a line of code.

Regards,
Steven Perryman Received on Mon Oct 01 2001 - 04:51:27 CDT