- From: Eric Hellman <eric@openly.com>
- Date: Wed, 17 Nov 1999 15:50:55 -0500
- To: "Tim Berners-Lee" <timbl@w3.org>, <www-rdf-interest@w3.org>
I found this to be very interesting, and also the responses from Sergey, Stefan and others. I think that TimBL (and the Cambridge [communique]) is trying to address the fact that for those of us who are unschooled in metadata and knowledge representation, RDF is difficult to use. The different syntaxes make it very easy to make mistakes when composing it by hand, and I agree that it is the "striping" which makes it hard. Thus, while RDF is not hard to understand, it's hard to "speak". However, I don't find that TimBL's "simpler" syntax is a whole lot easier. I agree with Sergey Melnik's analysis of the problem. His atomic syntax IS very easy. Perhaps if the goal of "simple" XML were less ambitious than a complete expression of RDF, and scaled back to simple mark-up, then Sergey's syntax could be almost directly applied. I find that XML lends itself quite nicely to representing data structures. A goal of "RDF Markup" might be to avoid any alteration of the XML tree structure. It would then be easy to decouple the RDF from the XML. My guess is that in the majority of cases, rdf markup of xml is a matter of attaching simple self-referential statements to elements. The relevant statements to put on an "element" would be (subject = this ) <myTag rdfm:predicate="URI" rdfm:object="URI"/> <myTag rdfm:subject="URI" rdfm:predicate="URI">literal</myTag> (predicate = this ) <myTag rdfm:subject="URI" rdfm:object="URI"/> <myTag rdfm:subject="URI">literal</myTag> (object= this) <myTag rdfm:subject="URI" rdfm:predicate="URI">literal</myTag> URI could include "parent" and "child" (I'm assuming that there is an xpath or xpointer to make these into URI?) This should be trivial to parse, as each statement is strictly local to an element. At 6:12 PM -0500 11/16/99, Tim Berners-Lee wrote: >The Cambridge [communique] meeting had a consensus that a simpler syntax for >RDF. At the time I mentioned that I had done some thinking about it. The >results are at > >http://www.w3.org/DesignIssues/Syntax > >Comments welcome. > >The basic idea is that XML elements represent RDF properties: there is >no "striping" as in the standard RDF syntax, in which alternate layers in >the nesting >represent node types and arc types. In the "unstriped" syntax, >node types (if used) can be made explicit by an arc, or can be deduced from >the domain and range of properties. > >I have found that many applications seem to look (to me!!) much more >obvious in this syntax. > >The document is not totally baked (say where it doesn't make sense) >but I think the next step should be code. >I would love to be able to find time to do it myself, but help is of course >useful. > >Things which I was considering were > >- an XSLT transform from unstriped to striped syntax (and/or back). >- a modified RDF parser in your favorite language which accepts either >current or unstriped syntax. > >The page does not have examples - but the syntax is used in some >accompanying >pages such as http://www.w3.org/DesignIssues/Toolbox.html > >Tim Berners-Lee >no hat Eric Hellman Openly Informatics, Inc. http://www.openly.com/ 21st Century Information Infrastructure
Received on Wednesday, 17 November 1999 15:51:05 UTC