RE: multiple inheritance
Dear Colleagues,
Maybe I am more used to living in an imperfect world.
I would have two responses:
1. Is there another standard I could use instead of XML Schema to meet my
needs? (the nice thing about standards is that there are so many to choose
from) ;-( But seriously standards are a market place and you should vote
with your feet on standards that are not fit for purpose.
2. If there isn't something better (or XML-Schema is otherwise compelling -
e.g. someone is paying you to do it) then I would work at a meta-model
level, so instead of defining an ontology in an XML-Schema, I would create
an XML-Schema for ontologies that supported multiple inheritance. At that
level I could bear the single inheritance model, since I have a simple
purpose.
I quite accept that a single inheritance model for an ontology of any
complexity is asking for trouble.
Regards
Matthew
============================================
Matthew West
Operations & Asset Management
Shell Services International
H3229, Shell Centre, London, SE1 7NA, UK.
Tel: +44 207 934 4490 Fax: 7929
Exchange e-mail: Matthew.R.West@is.shell.com
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http://www.shellservices.com/
============================================
> -----Original Message-----
> From: Christopher Spottiswoode [mailto:cms@metaset.com]
> Sent: 16 June 2000 15:32
> To: standard-upper-ontology@ieee.org
> Subject: RE: multiple inheritance
>
>
>
> Members of this list who are not on the XML.com list may
> appreciate being
> pointed to this paragraph from an article pointed to by the
> latest number from
> XML.com. (The article is at
> http://xml.com/pub/2000/06/xmleurope/schemas.html )
>
> The article reports on Henry Thompson, introduced as "an
> editor of the W3C
> XML Schemas specification", and is re his address, entitled
> "Reconstructing
> DTD Best Practice", at this week's XML Europe 2000 conference
> in Paris.
>
> "Thompson also explained that XML Schemas 1.0 would not
> include multiple
> inheritance, as the Working Group is keen to produce a strong
> design for a
> single inheritance model first. However, Thompson did not
> rule out that
> multiple inheritance could feature in a later version, and
> that a model similar
> to Java (single inheritance supplemented by interfaces) could
> still be
> considered at that time. The emphasis is clearly on getting
> the first version of
> XML Schemas complete."
>
> While I myself find it difficult to imagine a congenial
> conceptual world without
> multiple inheritance, I do find it interesting to ponder the W3C WG's
> strategies, where they come from, and what implications such
> work from
> such a massively influential stable will have on the
> practical future of
> ontologies.
>
> A next question might be what features a first-pass
> single-inheritance
> ontology should have if it is to grow, in due course, into
> multiple inheritance,
> and without enormous inconvenience. (It is reportedly aiming to be
> "complete", and presumably it aims to be open too.)
>
> Christopher.
>