- From: Richard H. McCullough <rhm@PioneerCA.com>
- Date: Sun, 6 Jul 2008 12:17:17 -0700
- To: "Michael Kay" <mike@saxonica.com>, "'Alan Ruttenberg'" <alanruttenberg@gmail.com>, "'Rob Shearer'" <rob.shearer@comlab.ox.ac.uk>, "Dave Peterson" <davep@iit.edu>
- Cc: <public-webont-comments@w3.org>, <public-owl-wg@w3.org>, <www-xml-schema-comments@w3.org>
FYI When I designed the mKR language, I purposely avoided placing any constraints on the space,time,view specification of context. This permits the user to choose whatever level of detail is appropriate in a given situation. The resulting descriptions are always useful, and sometimes just plain fun! Some of my specifications: space, time = here, now time = past, present, future time = yesterday, today space = my house, the store view = Aristotle, feminist view = RDF, OWL, mKR, CycL, Amazon, Google Dick ----- Original Message ----- From: "Dave Peterson" <davep@iit.edu> To: "Michael Kay" <mike@saxonica.com>; "'Alan Ruttenberg'" <alanruttenberg@gmail.com>; "'Rob Shearer'" <rob.shearer@comlab.ox.ac.uk> Cc: <public-webont-comments@w3.org>; <public-owl-wg@w3.org>; <www-xml-schema-comments@w3.org> Sent: Sunday, July 06, 2008 6:51 AM Subject: RE: ISSUE-126 (Revisit Datatypes): A new proposal for the real <-> float <-> double conundrum > > At 10:13 AM +0100 2008-07-06, Michael Kay wrote: >> > >>> I don't see that moments in time, segments of time, and >>> repeating intervals make up a sensible datatype. That's my >>> particular problem with the idea. >> >>Well, one can certainly conceive of a generalization of these types that >>is >>a three-dimensional space whose axes are the start instant (perhaps >>unknown), the duration (perhaps zero), and the interval between repeats >>(perhaps infinite). Alternatively, and perhaps more conveniently, you can >>think of it as a seven-dimensional space containing year, month, day, >>hour, >>minute, second, and timezone-offset, allowing components at either end to >>be >>omitted, where the absence of a high-order component indicates a repeating >>interval and the absence of a low-order component indicates a time span. >> >>E.g., how does one define order? Is 14:00:00 less than or equal to 1997? >> >>You could define an ordering (if you wanted to) by filling in the gaps, >>treating 14:00:00 as say 0000-01-01T14:00:00 and 1997 as >>1997-01-01T00:00:00. Or you could say that the new primitive type is >>unordered, only the subtypes are ordered, as we do with the two duration >>subtypes. >>> >>> I'm curious how the simplification would be effected for QT. >> >>Difficult to do retrospectively, but with such a type, instead of XSLT >>defining three functions format-date, format-time, and format-dateTime, it >>could have defined a single function which would work perfectly well on >>all >>eight types, as well as on other logically-consistent subtypes like >>gHourMinute. > > Good ideas all. Fodder for Schema 2.0, I'd say. It takes time to > think these things out; equality didn't diverge from identity in 1.0 > because we didn't have time to think out the ramifications. Sigh-- > even standards creation is a publish-or-perish world, and if a version > of the standard doesn't get out the door in a reasonable time, even > if the possible improvements haven't been thought out yet, the > creating standards group finds its resources gone and no standard > at all gets out. > > One does the best one can, and hopes one hasn't closed off too many > useful possibilities for the next round--or left things totally > screwed up by not closing up some loopholes that leave the standard > useless. A fine balancing act. > > (This, of course, is preaching to the choir WRT Mike Kay himself; > he's been involved in the production of at least several standards.) > -- > Dave Peterson > SGMLWorks! > > davep@iit.edu > > Dick McCullough http://mKRmKE.org/ Ayn Rand do speak od mKR done; knowledge := man do identify od existent done; knowledge haspart proposition list; mKE do enhance od "Real Intelligence" done;
Received on Sunday, 6 July 2008 19:37:35 UTC