- From: pat hayes <phayes@ihmc.us>
- Date: Wed, 12 Nov 2003 17:36:14 -0600
- To: Dan Connolly <connolly@w3.org>
- Cc: w3c-rdfcore-wg@w3.org
>On Fri, 2003-11-07 at 16:11, Jan Grant wrote: >> One final option has occurred to me, which may have merit. > >Seems like a good balance between quick-and-dirty and squeaky-clean. > >> Currently the reason that there may be multiple entailmentRules >> specified for an entailment test case is to allude (strongly) to the >> idea that support for different styles of reasoner as one "moves up the >> stack" can be built by adding additional sets of axioms on top of >> previous layers. >> >> That may or may not actually be the case; however, for the purposes of a >> test case manifest, we need only a single "constant" value to indicate >> (via indirection) _all_ the entailment rules that should be held to be >> in force. > >yup. > >> That is, currently an RDFS-entailment test is expressed by saying >> (effectively) that both the rdf- and rdfs-entailment axioms are >> in effect. >> >> This idea is perhaps past its prime; thus, for the purposes of >> selecting entailment rules, the cardinality of test:entailmentRules >> should be exactly one, to choose between entailment tests that are: >> simple, rdf, rdfs, or datatype-aware (which implies rdfs entailment). > >er... really? datatype-awareness implies rdfs? I wasn't >aware of that. I'm not at all sure I believe it. For anything other than rdf:XMLLiteral, yes, because rdfs:Datatype isn't in the RDF vocabulary. Its true you hardly need any RDFS machinery in order to do datatyping, though. Pat > >> The point about datatype selection in the last case being closed-world >> is still true. To really deal with that, the expression of >> "supported datatypes" should be done using a parseType=collection-style >> rdf:List. > >that appeals to my intuition, though we haven't finished our >cwm-based harness work, so I can't say with much confidence >whether I need it. > >> >> >> Again, this involves some changes to the test case document, together >> with changes to manifest files. The largest changes are to the >> descriptions of datatype-aware test cases. It is "correct" in that it >> still does away with the closed-world clunkiness of the previous format; >> for the purposes of selection of test cases of a particular type, a test >> case harness that's built around an rdf graph will require fewer >> changes. >> >> Looking at the WebOnt test cases for impact: >> >> - WebOnt don't use test:entailmentRules, they utilise their own "level" >> property (with values "Lite", "DL", "Full"); therefore a change to this >> property will have no effect. (This applies to all options). >> >> - WebOnt use a simple (non-List) format for datatype suport >> declarations. This property is defined by WebOnt's test case format >> without reference to the RDF Test case schema, so would also be >> unaffected. (This applies to all options). >> >> >> In summary, there are a number of options to attempt to fix the >> "closed-worldness" of the test case manifest format. Alternatively, the >> "minimal" change would be to disregard DanC/Sandro's closed-world >> issue. (It perhaps behooves the WG to not put its name to a document >> which adopts a worldview antithetical to RDF.) >> >> The test cases themselves would remain essentially unchanged. The >> description of those test cases is moved towards being a more "correct" >> application of RDF. >> >> In any case, I can only apologise to the WG that this has arisen as an >> issue so late in the day; > >On the contrary! Your attention to detail >throughout the lifetime of this WG is exemplary. > >The WG made the "we're ready for PR" decision together. >We could have given you more time for this sort of thing, >but we didn't. We could have decided to do a Call For >Implementations and have a nice liesurely CR period in >which to work out these details, but we didn't. > >We accept that we could make this stuff better forever, >but eventually, you gotta shoot the engineers and ship it! > >I'll take your apology as evidence that you're taking >seriously the decisions delegated to you by the WG, >but I really don't see anything to apologize for. > >> I resisted my urge to put such a change on the >> agenda for a long time because the authors of test case harnesses >> appeared happy with the status quo, and I didn't want to spring extra >> effort on them while they were doing such an ace job of running our >> tests :-( >> >> jan >-- >Dan Connolly, W3C http://www.w3.org/People/Connolly/ -- --------------------------------------------------------------------- IHMC (850)434 8903 or (650)494 3973 home 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32501 (850)291 0667 cell phayes@ihmc.us http://www.ihmc.us/users/phayes
Received on Wednesday, 12 November 2003 18:36:16 UTC