- From: Mike Taylor <mike@indexdata.com>
- Date: Thu, 27 Mar 2003 16:52:12 GMT
- To: a.powell@ukoln.ac.uk
- CC: matthew.dovey@las.ox.ac.uk, www-zig@w3.org
> Date: Thu, 27 Mar 2003 12:46:54 +0000 (GMT) > From: Andy Powell <a.powell@ukoln.ac.uk> > > [Matthew's suggested solution to Theo's problem] sounds reasonable > to me... but there is one thing that might be worth thinking > about... > > Is an application profile that uses 1 DC element and 50 IEEE LOM > elements a 'loose simple DC' application or a 'loose IEEE LOM' > application or both or either? ;-) The point being that the naming > above (and Theo's DCX name) takes a very DC-centric view of the > world. Does this matter? This is pretty much the point at which the discussion broke down when we tried to thrash this out on the ZNG list. Theo seems to have a "pornographic" definition of a DC record: "I can't define it, but I know it when I see it" :-) So my stab at the general solution that I think we need is as follows: we take a sort of OO approach to Schemas, declare that when a client as for schema B, the server can return D where D is a derived class of B. Confused? Don't be. Take a nice, rigorous DC-simple schema. My client asks for DC-simple and the server gives it to me. But if instead it has DC-qualified records, and if DC-qualified is known to be a subclass of DC-simple, then it's at liberty to give me those as well. Likewise, it could give me DC-plus-some-bits-from-IEEE-LOM records provided that schema is a subclass of DC-simple. (We'd also want to send a bit in the present request saying whether this sort of thing is acceptable, so that you can still ask for "DC-simple, dammit, and none of your qualified nonsense!") The issue here seems to be, what do we mean by one schema being "derived from" another? Is there a ready-made answer to this from the world of XML Schema? Or do we have to invent such a notion? _/|_ _______________________________________________________________ /o ) \/ Mike Taylor <mike@indexdata.com> http://www.miketaylor.org.uk )_v__/\ "That which gets lost in translation" -- Robert Frost's definition of poetry. -- Listen to my wife's new CD of kids' music, _Child's Play_, at http://www.pipedreaming.org.uk/childsplay/
Received on Thursday, 27 March 2003 11:53:45 UTC