Comment on POWDER WDR, 2008-06-30: should use rdf:ID

Comment on http://www.w3.org/TR/2008/WD-powder-dr-20080630/

This may be a bug in the GRDDL or simply in the document.

In example 2.11 powder2.rdf cannot refer to a blank node defined by 
powder1.rdf, which it currently does by

<rdfs:subClassOf rdf:resource="powder1.rdf#ks_1"

where ks_1 is an rdf:nodeID value in powser1.rdf.

I suspect the intention is that all xml:id values are translated into 
rdf:ID, which makes them referenceable. Ie, in the powder1.rdf file:


- rdf:nodeID="ks_1" should be rdf:ID="ks_1"
- rdf:nodeID="ks_2" should be rdf:ID="ks_2"

Note, however, that if a mechanical xml:id -> rdf:ID mechanism is used, 
that will affect example 2-14 (as well as the argument stated somewhere 
at the beginning that the usage of blank node means that nobody from the 
'outside' can massage with those). It is up to the WG to decide whether 
this is an issue or not. Maybe, for the purpose of 2-14, there should be 
two different identification mechanisms: xml:id for a universally 
visible ID and something like 'id' for internal purposes only (ie, 
introducing blank nodes without talking about them:-)

Ivan

P.S. Editorial comment: it is very handy that you had line numbers added 
to all previous examples. Why don't you do that for all?


-- 

Ivan Herman, W3C Semantic Web Activity Lead
Home: http://www.w3.org/People/Ivan/
PGP Key: http://www.ivan-herman.net/pgpkey.html
FOAF: http://www.ivan-herman.net/foaf.rdf