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.