- From: Patrick Stickler <patrick.stickler@nokia.com>
- Date: Mon, 08 Apr 2002 12:38:43 +0300
- To: RDF Core <w3c-rdfcore-wg@w3.org>
Jeremy's recent posts regarding entailments between the idioms suggests that there is an important question that seems to need answering, namely, do we wish/expect/need that a given datatype value (member of a datatype value space) always and only be denoted by a single node in the graph? (as opposed to it being denoted by a combination of nodes or statements such as the inline idiom with an rdfd:range assertion). If the answer to that question is no, then I don't see any problem with the present proposal. The lexical form and datatype property idioms provide single node denotation. The inline idiom does not. But that is just the way things are. (see below) It seems that Jeremy's answer would be yes, which is why the present proposal (which does not provide a single node denotation for the inline idiom) is unnacceptable. If the answer to the question actually is yes, then I see two reasonable options: 1. Exclude the inline idiom from the datatyping solution. If folks use it, fine, but it will have no official interpretation and its use will be application-specific. The bnode of the lexical form or datatype property idioms denotes the value and if you don't use one of those idioms, you don't have any explicit denotation of the value in the graph and you're not doing "standard" RDF Datatyping. 2. Make literals untidy and have the literal node denote the value in the case of the inline idiom. Though, this introduces an oddness to the bnode idioms if the bnode then denotes the value and the literal node object of rdfd:lex or datatype property does not (i.e. is just the literal) unless we say that for the bnode idioms both the bnode and the literal node denote the value (which is still odd). -- My personal feeling is that the answer need not be yes, in that it need not be an absolute requirement that the value always and only have a single node denotation. We may simply accept that the inline idiom does not provide an explicit, single node denotation of the value and if you need/want such an explicit, single node denotation, don't use the inline idiom -- or transform all occurrences of the inline idiom to the lexical form idiom (or some other idiom) for your specific application. But this is a question for the WG to decide, and that decision should be made as soon as possible. It may very well be that OWL, DAML, etc. require only single node denotation and allowing even the possibility of the inline idiom is problemmatic, in which case, we should give such needs serious consideration in deciding an answer to this question. I expect that this decsision can be made via email discussion, but we could also include it in this Friday's aggenda (Brian?). Patrick -- Patrick Stickler Phone: +358 50 483 9453 Senior Research Scientist Fax: +358 7180 35409 Nokia Research Center Email: patrick.stickler@nokia.com
Received on Monday, 8 April 2002 05:36:12 UTC