Re: Error in RDF/XML Syntax Specification?

On Tue, 5 Apr 2005 13:46:18 -0400, Dan Brickley <danbri@w3.org> wrote:

> New version: http://www.w3.org/2001/sw/RDFCore/errata#rdf-syntax-grammar
> 
> Incorporating Graham's qualifier, a typo fix from Pat Hayes, and a
> closing observation I could do with someone reviewing (tried to 
> interpret Dave's IRC comment that this was really 2 issues...):
> [[
> Serialization of datatyped empty literals is not anticipated by the
> RDF/XML grammar.
> 
> This is believed by several developers and former WG-members to be an
> omission in the grammar defined by the RDF/XML Syntax Specification: a
> bug was reported (and acknowledged by the editor), relating to the use
> of an rdf:datatype attribute on empty RDF properties. See the archived
> mailing list thread for technical details. In addition to the question
> of the RDF/XML grammar's syntactic completeness, note that this issue
> identifies a construct that occurs within RDF graphs that cannot be
> serialized in the RDF/XML syntax. 
> ]]
> 
> Is that last claim right? Is there a difference btw between
> 
> <foo:prop rdf:datatype="http://www.w3.org/2001/XMLSchema#string"
> 	></foo:prop>
> 
> ...versus:
> 
> 	<foo:prop rdf:datatype="http://www.w3.org/2001/XMLSchema#string"/>
> 
> ...in terms of this issue and the grammar productions?

That's too many questions.

Yes, in XML terms (XML infoset) they are the same XML.

In RDF/XML as presently defined they are both illegal.

They are both fragments of examples of RDF/XML covered by this issue.

It was my intention as editor of the RDF/XML spec that both of these
forms would be in the RDF/XML grammar and generate an RDF triple; as
they are (the same) legal RDF triple.

Dave