- From: Dan Brickley <danbri@w3.org>
- Date: Thu, 7 Aug 2003 08:17:04 -0400
- To: Brian McBride <bwm@hplb.hpl.hp.com>
- Cc: rdf core <w3c-rdfcore-wg@w3.org>
* Brian McBride <bwm@hplb.hpl.hp.com> [2003-08-06 12:29+0100] > > It seems that there is some concern about XMLLiterals denoting octet > sequences. As I understand things, RDFCore doesn't feel strongly that > the denotation MUST be octet sequences. Pat has layed what we really > care about in: > > http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Jul/0452.html > > I suggest we accept Pat's suggestion and reconsider the denotation of > XMLLiterals. I have seen three suggestions, as I recall: > > A) be a bit vague about XMLLiterals really are - just define their > essential properties > > B) have them denote XPATH nodesets > > C) have them denote a pair (uri, lex form), where uri is the uri of > rdf:XMLLiteral. > > Concern has been expressed about A being to vague. Others have > responded saying thats normal - integers are defined in terms of their > properties. > > Concern has been expressed that XPATH nodesets are too vague, we don't > really know that they are and are thus no better than A, but are in some > way worse. Cannonicalization does define an equality relation on them > > I have heard a private concern expressed about C, that if we did that, > shouldn't we treat all datatypes that way. Further, that this does > guarantee that there are no other ways of denoting the same pair with > another, posibly user defined datatype. > > How do we choose? If you have a preference and rationale, it would be > good hear it. Thinking about this some more, I'm increasingly uncomfortable with the idea of picking one of these 3 somewhat different answers, and then storming on to REC without another cycle of external review. The relationship(s) between RDF and XML is _the_ big problem that's haunted the entire RDF project since 1997. To be having such a straw poll at this stage, without expectation of major review from the RDF and XML developer community, is a cause for concern. Nobody's fault but that's where we're at. If the choices A, B, C actually mean anything and matter, and have substantive differences amongst them, I suggest the answer to your question 'how do we choose' is 'with outside help from XML and RDF implementors'. If A, B and C don't really have any observable differences in the workings of an RDF implementation, maybe this wouldn't matter. But we seem to be discussing the choice as if it was a real one with consequences that matter in the world. Declaring a dependency on some version of XPath, for example, is a non-trivial thing to do. I'm coming round to the view that we need a CR[1]. In 1999, RDF M+S was promoted prematurely to REC with minimal implementation experience; we're still cleaning up the resulting mess. I fear we're about to do the same thing regarding RDF's relationship to XML. If A vs B vs C is non-trivial, a CR will help us evaluate our decision. If it is trivial and our decision doesn't matter at all, then let's just flip a 3-sided coin... Dan [1] http://www.w3.org/2003/06/Process-20030618/tr.html#q70
Received on Thursday, 7 August 2003 08:17:04 UTC