- From: Jeni Tennison <jeni@jenitennison.com>
- Date: Fri, 29 Jul 2011 19:47:52 +0100
- To: Tim Berners-Lee <timbl@w3.org>
- Cc: Michael Hausenblas <michael.hausenblas@deri.org>, Richard Cyganiak <richard.cyganiak@deri.org>, "www-tag@w3.org List" <www-tag@w3.org>
Tim, On 28 Jul 2011, at 18:19, Tim Berners-Lee wrote: > On 2011-07 -27, at 17:25, Jeni Tennison wrote: >> IIRC, one reason that Hixie gives for the complexity of the generated property URIs in the current microdata/RDF mapping is to ensure that properties with potentially different semantics (that appear on items of different types) have distinct URIs. But of course when you have inheritance in a vocabulary like schema.org, you don't want distinct URIs by type. >> >> Makes me think you can't have a generic mapping that gives a good output in RDF terms. > > Yes. It is important that the semantics of the property is the same, as this gives much greater power of data re-use. > > I think the spec can't just specify the syntax, it has to specify the RDF > mapping. It is only well-defined when it has defined the > mapping from the HTML DOM into abstract RDF triples. > People don't have to use the DOM or the RDF model in their code > but as those are the abstractions which we have written a lot of > code in terms of, that is the reference point for the spec to > produce interoperability. I agree that it's important to have a mapping. I don't see that it needs to be done within the microdata spec to be useful. I think it's something that can be layered on top of microdata in the same way that GRDDL was layered on top of XHTML. > It can't be a mapping which maps to a notional URI which is hopeless > in practice. It has to map to a URI which looks just like the normal sort of URIs > which RDF systems use, supported on the web as linked data, like FOAF, etc. I agree. The current microdata/RDF mapping penalises people who want to reuse vocabularies that have been developed for RDF because they can't use simple short-name properties but have to use URIs for properties. Jeni -- Jeni Tennison http://www.jenitennison.com
Received on Friday, 29 July 2011 18:48:30 UTC