Re: On Formal IS-A definition

From: Erwin <>
Date: Thu, 6 May 2010 16:18:28 -0700 (PDT)
Message-ID: <>

On 7 mei, 01:13, David BL <> wrote:
> On May 6, 9:10 pm, Bob Badour <> wrote:
> There is no subtype relationship between ellipse variables and circle
> variables (in either direction).

Look for a (very old) post by Jan Hidders on this subject.

Strange as it may seem, it explains very well what is actually meant by this weard claim that a variable can be considered as being a subtype of another variable.

Even I understood it, at the time I was reading that particular post. Received on Thu May 06 2010 - 18:18:28 CDT

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