Re: New RDDL draft

I didn't grok this when I initiall scanned it.
Tonight I read it slowly and I still don't grok;
hence some clarifying questions...

On Wed, 2003-09-17 at 12:29, Jonathan Borden wrote:
> Tim Bray wrote:
> 
> > My action item is half-done, I need to do the following:
> >
> > - add a "hello world" example near the top of the doc
> > - produce a normative transformation into RDF, probably XSLT
> 
> There are a few nitty gritty issues which raise their heads when 
> considering the RDF transformation.
> 
> First I will outline what should be a straightforward protocol for the 
> transformation, then I will point out where these issues fail to get 
> properly addressed:
> 
> Assume a RDDL fragment (from Tim's most recent draft):
> 
> <a rddl:nature="http://www.rddl.org/"
>    rddl:purpose="http://www.rddl.org/purposes#directory"
>    href="http://www.rddl.org/natures">http://www.rddl.org/natures</a>
> 
> 1. The subject of an RDF statement is derived in the following fashion:
> 
> 2. If the there is an _id_ attribute e.g. <a id="foo" ...> this should 
> be the fragment identifier of the RDF subject URI.
> 3. The URI part of the RDF subject URI should be the current base URI 
> (absolute).

current... you're starting to lose me there.

> 
> 4. The predicate is the value of the _rddl:purpose_ attribute.
> 5. The object is the value of the _href_ attribute.
> 6. If a rddl:nature attribute is present, this generates a second triple 
> of the form:
> [value of href] rdf:type [value of rddl:nature]
> 
> This generally works but stumbles when a namespace name is not simply an 
> absolute URI, rather contains a '#' either an ending '#' or a fragment 
> identifier part.

Which of the things above corresponds to the namespace name here?


> That is to say, suppose a namespace name of the typical RDF type e.g. 
> <http://example.com/rdf#>.

OK, now I'm totally lost. Where do I plug that namespace
name into the example framework above?


> The problem is that a user agent will strip off the ending '#' when 
> dereferencing the URIref and the base URI will simply be 
> <http://example.com/rdf>. How do we tell the software performing the 
> RDDL -> RDF transformation that the intended namespace is actually 
> <http://example.org/rdf#> as opposed to <http://example.org/rdf> when 
> the RDDL document itself does not contain this information?

Sorry, I need more clues.

Could you flesh out more of the details and use a more
concrete example please?

>  Do we need a 
> specific attribute e.g. rddl:namespace="http://example.com/rdf#" which 
> states the one and only namespace described by the specific RDDL 
> document (you see the problem that each RDDL document would only be able 
> to describe a single namespace in this case).
> 
> Am I missing a straightforward way to tell the software what the correct 
> intended subject of the RDF statement is without embedding this in the 
> document itself?
> 
> Jonathan
-- 
Dan Connolly, W3C http://www.w3.org/People/Connolly/

Received on Wednesday, 1 October 2003 01:02:47 UTC