- From: Graham Klyne <Graham.Klyne@Baltimore.com>
- Date: Sat, 16 Jun 2001 20:41:56 +0100
- To: Sergey Melnik <melnik@db.stanford.edu>
- Cc: rdf core <w3c-rdfcore-wg@w3.org>
Sergey, I think you're suggesting that relative URIs be regarded as syntactic sugar in a surface syntax. If so, I agree. #g -- At 03:58 PM 6/15/01 -0700, Sergey Melnik wrote: >Currently, the concept of relative URIs is present in the M&S 1.0 >serialization syntax only, and is not reflected in the model in any way. >That is, relative URIs is a just another "abbreviation feature" of the >M&S syntax, and I'd like to emphasize that in the revised spec to avoid >misconceptions. As abbreviation features, relative URIs have nothing to >do with the fragment IDs described in >http://www.w3.org/DesignIssues/Model.html#Fragement (for example, a >fragment ID in an RDF document does *not* refer to a portion of this >document). Therefore, IMO the axioms and benefits summarized by TimBL >for HTML at above link do not seem to hold in the RDF world. > >I feel strongly about not using relative URIs, especially given the >parsing/editing complication (see prev. postings in this thread), and >the problems associated with moving RDF documents from one location to >another. However, I think keeping cleaned-up rdf:ID, rdf:about and >relative URIs in the revised M&S syntax is essential for backward >compatibility and is the least bloody compromise (sigh...) I'd just >suggest to word it so the developers understand the pros and cons. > >Sergey > >Dan Connolly wrote: > > > > "R.V.Guha" wrote: > > > > > > Ok, Aaron, you hit the nail on the head. > > > > > > RDF absolutely has to make sense even outside the context of > > > an enclosing document which can be given a uri. so ... > > > > So... what? That doesn't make any sense to me. > > > > An RDF document is an XML document. Each XML document > > has a base URI (cf the infoset spec). > > If you copy the contents from one > > place in the web to another, you get a different XML > > document, and hence a difference RDF document; if > > it uses relative URI references, the resulting triples > > may be different. > > > > This is by design. > > > > This design does allow users to goof, > > but it also allows folks to manage collections of > > documents and by and large, it has succeeded over the course > > of the last 10 years. > > > > Noone is forced to use relative URI references; anyone > > who uses them does so by choice. Surely the consequences > > of that choice for RDF documents should be the same > > as the consequences for HTML, XML, PDF, > > and other document formats in the Web, no? > > > > Or rather: surely the the consequences *are* the same for > > RDF as for XML in general; we're not designing RDF 1.0 today; > > we're just clarifying the spec; and the spec is already > > pretty clear on this: > > > > [[[ The value of the about attribute is interpreted as > > a URI-reference per Section 4 of [URI]. The corresponding > > resource identifier is obtained by resolving the > > URI-reference to absolute form as specified by [URI]. > > ]]] > > > > -- Resource Description Framework (RDF) Model and Syntax > > Specification > > http://www.w3.org/TR/REC-rdf-syntax/ > > Wed, 24 Feb 1999 14:45:07 GMT > > > > The only question is about this sort of fuzzy text: > > > > [[[ The ID attribute signals the creation of a new resource ... ]]] > > > > But this text in particular suggests pretty strongly > > that rdf:ID="foo" means the same thing as rdf:about="#foo" : > > > > [[[ The ID attribute, if specified, provides the URI > > fragment identifier for c. > > ]]] > > > > -- section 6. Formal Grammar for RDF > > > > -- > > Dan Connolly, W3C http://www.w3.org/People/Connolly/ ------------------------------------------------------------ Graham Klyne Baltimore Technologies Strategic Research Content Security Group <Graham.Klyne@Baltimore.com> <http://www.mimesweeper.com> <http://www.baltimore.com> ------------------------------------------------------------
Received on Saturday, 16 June 2001 16:20:10 UTC