- From: Graham Klyne <GK@NineByNine.org>
- Date: Wed, 30 Jan 2002 16:00:36 +0000
- To: www-archive@w3.org
[From a comment to Jeremy Carroll about a model theoretic formulation for the TDL proposal for datatyping in RDF.] For background, see also: http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Jan/0344.html http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Jan/0369.html http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Jan/0384.html http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Jan/0353.html http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Jan/0349.html (and other messages in that thread.) Also, a thread starting with: http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Jan/0224.html ----- I have an inkling that a model theory that treated all literals existentially, without introducing extra nodes, might just work for TDL. Sketch: (a) Literals denote <value,string> pairs as previously noted. (b) Interpretation (of statements containing literals) is with respect to a defined set of data types DT, where each d in DT is a set of pairs of the form <value,string> -- i.e. a datatype map. (DT would be a subset of IC, mapped to a subset of IC, I think.) (c) a triple I(aaa bbb "foo") is true if there exists a value v such that <v,"foo"> is in the union of the members of DT, and <I(aaa),v> is in IEXT(I(bbb)). Roughly, the statement is true if there exists any datatype mapping that makes it true. If the set DT is required to contain the identity mapping of strings (dstring: (<x,x>:for all strings x that can be used as literal node labels>), then I think the self-entailment of documents containing literals follows. This is all intuitive; I'm not sure I could prove it. -------------------------- __ /\ \ Graham Klyne / \ \ (GK@ACM.ORG) / /\ \ \ / / /\ \ \ / / /__\_\ \ / / /________\ \/___________/
Received on Wednesday, 30 January 2002 11:00:51 UTC