- From: Jim Hendler <hendler@cs.rpi.edu>
- Date: Wed, 6 Feb 2008 20:36:25 -0500
- To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>
- Cc: public-owl-wg@w3.org
you're right - I had forgotten it was a subclass of object property -- and interestingly, so did the people who built the demo we showed the DARPA Director to keep the project funded after I left, in fact, it made heavy use of "keys" implemented as datatypes (airport codes and some classfied things that were similar) - I guess whatever one puts in the formal specs, there's those who will do what they want... of course, by the time we got to the WOWG, data modeling had grown in importance in the Sem Web world (and even more now)... that said, a key difference between what we had in DAML+OIL and what came out of WOWG was the realization that some people had different needs than others and that working for consensus in an industrial Working Group was absolutely crucial. guess some stuff never changes -JH On Feb 6, 2008, at 8:25 PM, Peter F. Patel-Schneider wrote: > From: Jim Hendler <hendler@cs.rpi.edu> > Subject: Re: OWL Full proposal (sort of) - addressing my Action > Date: Wed, 6 Feb 2008 20:01:14 -0500 > >> As you'll recall. I was a big fan of the DAML+OIL situation, and feel >> that if we'd stayed closer to that model in OWL 1.0 we might have >> been >> better off. However, there was some functionality that was perimtted >> (or at least not forbidden) in DAML+OIL (cf. inverseFunctional >> Datatypes) that was not reflected in OWL DL. I am very happy to move >> forward to the past in this case :-) >> -JH >> p.s. One thing I didn't like in DAML+OIL was the QCR solution which >> required special syntax, so I guess we're back to the past in several >> ways :-) > > [...] > > Actually, in DAML+OIL UnambiguousProperty (read > InverseFunctionalProperty) was a subclass of ObjectProperty, so DAML > +OIL > did not allow inverse functional datatype properties at all. > > At http://www.daml.org/2001/03/reference#UnambigousProperty-def > > * an daml:UnambigousProperty element, which is a subclass of > ObjectProperty. > > This asserts that an instance y can only be the value of P for a > single instance x, i.e: there cannot be two distinct instances x1 and > x2 such that both (x1,y) and (x2,y) are both instances of P. Notice > that the inverse property of a UniqueProperty is always an > UnambigousProperty and vice versa. > > and in http://www.daml.org/2001/03/model-theoretic-semantics > > <rdf:type,?P,UnambiguousProperty> > for y in AD, if <x,y> in IR(?P) and <z,y> in IR(?P) then x=z > > > peter "If we knew what we were doing, it wouldn't be called research, would it?." - Albert Einstein Prof James Hendler http://www.cs.rpi.edu/~hendler Tetherless World Constellation Chair Computer Science Dept Rensselaer Polytechnic Institute, Troy NY 12180
Received on Thursday, 7 February 2008 01:36:36 UTC