- From: Patrick Stickler <patrick.stickler@nokia.com>
- Date: Fri, 15 Feb 2002 13:16:20 +0200
- To: ext Brian McBride <bwm@hplb.hpl.hp.com>, RDF Core <w3c-rdfcore-wg@w3.org>
On 2002-02-15 12:10, "ext Brian McBride" <bwm@hplb.hpl.hp.com> wrote: > At 11:04 15/02/2002 +0200, Patrick Stickler wrote: > [...] >> <dc:date rdf:value="2002-02-14" rdf:dtype="&xsd;date"/> > > Am I right that under the current proposal this can be more compactly written: > > <dc:date xsd:date="2002-02-14"/> Yes and no. It is more compact, but is less local (thus it is not exactly an equivalent variant of the doublet idiom). In this case, it is not clear from the RDF that xsd:date is a datatype. It could be any kind of property at all. It has no more datatyping clarity to the parser than <dc:date foo:bar="2002-02-14"/> And it is unclear, if e.g xml:lang is specified, whether the value of xsd:date or foo:bar is the actual literal value of the dc:date property or just some extra attribution of the bNode. Thus, schema knowledge would be required by the parser (not just pre-defined automatic statements in the spec) to know for sure that xsd:date or foo:bar should be treated as rdf:value. And one would not, I think, expect xml:lang to apply to all attributes of the element -- or really to any of the attributes, but rather only the content of the element, and it's just a trick of rdf:value that the content can be hidden (contracted) into an attribute. If I have <dc:title rdf:value="Foo" xml:lang="en" x:scope="237a87"/> we're saying that "Foo" is English, but not "237a87". Yet if I have <dc:title xsd:string="Foo" xml:lang="en" x:scope="237a87"/> how does the parser know which attribute, if any, denotes the actual content of the dc:title property element? Thus, with the datatype triple idiom, the parser cannot know what is or is not the content of the property element to which xml:lang is to be attached simply from the vocabulary used in the idiom itself. I admit that it's a handy form of expression, but these issues have to be resolved before we're completely done, I think. > which would require no change to the parsers? Correct, in that the required bNode is generated. Apologies for missing this in my earlier examples. Though, as pointed out above, proper attachment of xml:lang to the literal either requires schema knowledge or results in over-attachment to all attributes. 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 Friday, 15 February 2002 07:27:13 UTC