- From: Danny Ayers <danny666@virgilio.it>
- Date: Fri, 19 Dec 2003 13:05:45 +0100
- To: "Garret Wilson" <garret@globalmentor.com>, "Libby Miller" <Libby.Miller@bristol.ac.uk>
- Cc: <www-rdf-calendar@w3.org>
So DTD & XSD don't sound too promising..! I've seen this stuff talked about so many times, but I think this is the first time I've read what happens if you actually try it. Anyhow, I've no personal experience, but I believe RelaxNG allows a lot of flexibility not found in XSD - might that be an option? Cheers, Danny. > -----Original Message----- > From: www-rdf-calendar-request@w3.org > [mailto:www-rdf-calendar-request@w3.org]On Behalf Of Garret Wilson > Sent: 16 December 2003 18:03 > To: Libby Miller > Cc: www-rdf-calendar@w3.org > Subject: Re: Syntactic profile of RDFiCal? > > > > We explored this option for probably over a year with XPackage ( > http://www.xpackage.org/ ) in the Open eBook Forum (OEBF). We had really > strong pullback in the OEBF against the use of RDF, on the theory that > (1) we need to get book publishers to adopt OEB, (2) publishers can't > understand RDF, and therefore (3) we have to use plain XML. > > In the end, after the OEBF's plans for its next version stalled, I > decided to take out the normative XML Schema version of XPackage > altogether---it simply wasn't worth the effort. (The above logic forgot > to figure in that publishers don't understand XML, either.) I left in an > XML Schema version only for informative purposes. > > * Creating an XSD version of XPackage in many ways negated the benefits > of RDF. > > * As you mention, if we want collections we *must* require an "ugly" > rdf:parseType---it's not good enough to just make it a default attribute > in a DTD. > > * A pure XML version that is RDF-compatible still requires rules for > processing rdf:about/rdf:resource---unless you intend to make *every* > resource inline. > > * Extensibility is basically gone, unless you introduce rules about how > new XML elements can be added to the XML Schema, in ways that are RDF > compatible. At this point, you're almost creating a separate framework > that duplicates RDF. > > * With an XSD or DTD version, the pure RDF version would be useless, as > we would need to support the lowest common denominator. Otherwise, there > would be both a pure XML version and a pure RDF version, in which case > who cares if the XML version is RDF-compliant or not if there are two > versions anyway? > > I could go on and on. At first this sounds like a good idea, but the > more you try to *work* with it, you realize that it's just a feeble > attempt to placate those who claim they either (A) don't understand RDF, > or (B) don't see the need for it. Either of those is a dubious reason to > begin with, I've come to believe. > > (Is Patrick Stickler on the list? Maybe he can share some of his > opinions from helping me try to do this with XPackage.) > > Cheers, > > Garret Wilson > GlobalMentor, Inc. > > Libby Miller wrote: > > > > > hi, > > > > On the IETF calendar mailing list [1] they are currently talking about > > reviving Xcal, which was an XML DTD for iCalendar. I was wondering if > > we might want to think about a syntactic profile of RDFiCal, as the RSS > > 1.0 group did for RSS 1.0 with Leigh Dodd's Schematron schema [2], and > > as we have been doing in the foaf project, again with Leigh's help [3]. > > > > There are many disadvantages to doing this, the main one being that with > > all the RDF toolkits I have seen you can't control the output of the > > RDF, making a specific syntactic output difficult or awkward to create. > > > > Additionally, I think we might have to rethink some of the syntax that > > is currently outputted by the iCalendar to RDF tools, as it often uses > > parseType="resource", which can make it difficult to use other > > namespaces with it, e.g. > > > > http://swordfish.rdfweb.org/discovery/2003/09/foafcal/foaficaleg.rdf > > > > shows an example of using foaf:Person with attendee. regardless of > > whether this is the right way to do it, if we use > > > > <attendee rdf:parseType='Resource'> > > > > in a syntactic profile, then there's no way we can get the foaf:Person > > tag in there. And that may not be too important for some people who > > focus on properties, but our foaf experience suggests that many people > > focus on objects when manipulating foaf files for display (and don't do > > any inference from the schema). > > > > These caveats aside, I think an XML version of iCalendar that could be > > parsed and used by pure XML tools might be very well recieved, and > > we've done a lot of the hard work already. It'd be annoying to have > > another XML format in this space, although we could specify mappings to > > it if it was created. > > > > What do you think? > > > > Libby > > > > > > [1] http://www.imc.org/ietf-calendar/mail-archive/msg11885.html > > [2] http://www.ldodds.com/rss_validator/1.0/ > > [3] http://rdfweb.org/pipermail/rdfweb-dev/2003-August/011890.html (see > > thread for useful discussion of some of the potential issues) >
Received on Friday, 19 December 2003 07:14:09 UTC