- From: Jonathan Borden <jborden@mediaone.net>
- Date: Mon, 21 Jan 2002 16:51:47 -0500
- To: "Brian McBride" <bwm@hplb.hpl.hp.com>
- Cc: "Tim Bray" <tbray@textuality.com>, "Henry S. Thompson" <ht@cogsci.ed.ac.uk>, <www-rdf-comments@w3.org>
Brian, > Jonathan, > > In > > http://lists.w3.org/Archives/Public/www-rdf-comments/2001JanMar/0082.html > > you raised an issue which was captured in: > > http://www.w3.org/2000/03/rdf-tracking/#rdfms-qname-uri-mapping > > as > > [[[ > The algorithm for mapping a QName in the RDF XML syntax to a URI is to > concatenate the URI of the namespace with the localname part of the QName. > In the case of namespaces, such as the XML Schema datatypes namespace, > which do not end in a "#" character, then the URI reference generated by > this algorithm is not the same as the conventional URI for the concept. > ]]] > > As recorded in > > http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Jan/0095.html > > the RDFCore WG resolved to not change the algorithm for mapping qnames to > uris and close this issue on the grounds: I find this unacceptable for the following reasons: 1) I have received nor have I found a proper analysis or explanation for the decision on any of the RDFCore WG archives. I will outline my objections to the three issues raised below. 2) The problem is that there is much talk in RDFCore and WebOnt WGs about leveraging XML Schema datatypes for both RDF and WOL. At the surface this seems an entirely reasonable and desirable thing to do. The problem is that XML Schema identifies types by QName, and unless there is a reasonable translation between QNames and URIs, RDF is likely to become more broken with time. Since my proposed solution, Henry Thompson has explained to me how the issues with QNames and URIs are even deeper than I first assumed, namely that one cannot generally derive a proper URI which corresponds to the QName that XML Schema uses to identify a particular type. It seems to me that the RDFCore and XMLSchema WGs (at the very least) ought to develop a common, reasonably acceptable convention as to the mapping between QNames and URIs. Perhaps this is an issue that the TAG ought to consider (because it is a really basic architectural issue). I have cc:'d both Henry Thompson and Tim Bray. If either of these individuals agree that this issue ought to be closed, then I will find that acceptable and will withdraw my current objection. > > 1. Such a change would be a major change to the > mapping of RDF/XML syntax to the model and > would be beyond our charter. The RDF 'model' itself has undergone major change indeed it has been completely rewritten. If it is not beyond the charter to completely rewrite the 'model' how could the model-syntax mapping possibly be beyond the charter? > > 2. It would cause the same RDF/XML to generate a > different graph from existing versus revised > implementations The same is true for many of the changes, even trivial changes which have already been decided upon. This is exemplified by the following trivial RDF 1 example: <rdf:Description about="http://example.com"> <rdf:type ID="baz" resource="http://example.org/bop"/> </rdf:Description> since the new syntax does not interpret the unqualified attribute "about" the same as "rdf:about", this example which was valid RDF 1 is not valid RDF 1.1 or whatever the current drafts are intended to be. > > 3. Existing code may generate wrong (illegal) > graphs for some RDF/XML. see above, same story. Jonathan
Received on Monday, 21 January 2002 16:21:39 UTC