- From: Pat Hayes <phayes@ihmc.us>
- Date: Sat, 18 Dec 2004 22:28:38 -0800
- To: Simon Raboczi <raboczi@tucanatech.com>
- Cc: public-rdf-dawg@w3.org
- Message-Id: <p06001f17bdeacd717038@[192.168.1.7]>
A quick response. Like Kendall http://lists.w3.org/Archives/Public/public-rdf-dawg/2004OctDec/0474.html I am very sympathetic to the idea of using triple syntax for constraints, and less worried than Kendall is about the awfulness of the collection/container syntax (It is indeed awful, but the collections at least are a familiar awfulness that we know how to code around.) However, there is another issue. Part of the very point of constraints is that they are not treated as patterns to match against, whereas triples in patterns are exactly intended for that. So making the constraints into patterns seems like it creates confusion. Your proposal to use the namespace to distinguish them is pragmatic, but seems to set a potentially dangerous precedent. What happens if someone wants to use this namespace in an ordinary RDF graph? Does a query which finds these triples in the target graph find itself obliged to match them and evaluate them? What if the graph asserts something that evaluates to false? You argue that RDF is supposed to be universal, and yes indeed; but remember its a universal notation for propositional assertions, not expressions intended for evaluation. So I can see a good positive case for having distinct syntax for patterns to be matched against, and for expressions to be evaluated. Anyway, its a good issue to have raised, thanks. Pat Hayes -- --------------------------------------------------------------------- IHMC (850)434 8903 or (650)494 3973 home 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32502 (850)291 0667 cell phayes@ihmc.us http://www.ihmc.us/users/phayes
Received on Sunday, 19 December 2004 06:29:33 UTC