So you say you want a revolution

[Ed Barkmeyer]

David Price wrote:
> So, P21 could say to ignore any attribute that does not have a type 
> that is instantiable. Then these attributes, all with the same name, 
> would simply appear in the subtypes, not in the ABSTRACT ENTITY. 

The problem with this approach is that the attribute may be
redeclared 
in more than one subtype in a complex entity instance, and you
get n
copies of the attribute, hopefully all with the same value.

> I'm not necessarily suggesting that I think this is the best approach. 
> I'm just suggesting that there is more than one way to address this issue.

Agreed.  There certainly are multiple approaches to solving this
problem
technically.  

-Ed
 

-- 
Edward J. Barkmeyer                       Email: edbark at nist.gov
National Institute of Standards & Technology
Manufacturing Systems Integration Division
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