- From: Jim Hendler <hendler@cs.rpi.edu>
- Date: Thu, 10 Jan 2008 19:57:16 -0500
- To: Bijan Parsia <bparsia@cs.man.ac.uk>
- Cc: "Web Ontology Language ((OWL)) Working Group WG" <public-owl-wg@w3.org>
- Message-Id: <D66C8252-D93A-456F-A859-8C9697125490@cs.rpi.edu>
wait, wait - now I'm even more confused than I was -- are we, or are we not, talking about the EasyKeys proposal being part of OWL 1.1? If so, wouldn't the last property in a property chain be implemented exactly the same way? If so, then we aren't closing the issue with a Reject, if not, then what is the difference? So couldn't we have "easykeys" at the end of property chains? -JH p.s. btw, I did look at Uli's slides, but without the accompanying explanation for the non-theorist, and there was very little in the log, the details were not terribly clear - I was assuming at some point there'd be some description of the solution in one of our documents. I On Jan 10, 2008, at 6:33 PM, Bijan Parsia wrote: > > On Jan 10, 2008, at 10:57 PM, Jim Hendler wrote: > >> I must admit to being confused- I thought the issue of property >> chains ending in data properties has the same decidability as >> inversefunctional datatypes - that is, that Uli has a suggestion >> we might adopt that fixes things (Bijan - you wailed on me when >> you thought i was ignoring this!) -- is there a reason these are >> different? If not, shouldn't the solution work for Issue 8 as well? > > The problem is that although decidable (though you have to be > careful, so the exact details of the proposal matter) like > *general* inversefunctional data properties, the implementation is > seriously non-trivial and there has been no evidence that *any* > implementor will implement it, at least, in a complete way. (This > is why we have an "EasyKeys" proposal in the works.) So, we > shouldn't *require* it as things stand now. However, if some > implementor wants to implement it, or some user wants it and will > pay some implementor, then they have syntax "ready to hand" (i.e., > it doesn't require inventing new terms, just relaxing some > restrictions on existing syntax). > > Ah yes, you weren't at the F2F so you might not have the design > principle I'm applying fresh to mind. At the first OWLED, the > guiding principles for adding features were: > 1) There had to be strong, committed user demand. (i.e., it > shouldn't just be "Nice to have I guess" but "I will use this") > 2) We had to have a good understanding of the feature, how to > implement it, etc. > 3) We had to have commitment from the implementors to actually > implement it. > > At the moment there's not the slightest evidence that any > implementor will implement this (the general feature). > > What I believe some implementor *will* do is implement something > similar to the corresponding DL-safe rules...but that's why we have > a RIF task force. > > Hence we close it until we get some evidence that it will be > implemented. (The general feature, of course.) > >> -JH >> p.s. I was told this about issue 8, I cannot tell for sure if it >> also is the case for issue-83, > > Issue-83 proposes an undecidable feature. > > Cheers, > Bijan. > "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 Friday, 11 January 2008 00:57:42 UTC