Re: Coments on first working draft of SPARQL

From: "Seaborne, Andy" <andy.seaborne@hp.com>
Subject: RE: Coments on first working draft of SPARQL
Date: Mon, 8 Nov 2004 09:21:53 -0000

> > On the contrary, the syntax of the language permits a URI to be a bNode
> > (or at least something of the form of a bnode) via
> > 
> > [43]	URI		 ::= 	QuotedURI | QName
> > [44]	QName		 ::=	<QName>
> > [48]	<QName>		 ::=	(<NCNAME>)? ":" <NCNAME>
> > [62]	<NCNAME>	 ::=	<NCCHAR1> (<NCCHAR1> | "." | "-" | ["0"-"9"] |
> > "\u00B7" )* [61]	<NCCHAR1>	 ::=	["A"-"Z"] | "_" | ...
> > 
> > So a URI can be, for example, _:A
> 
> Interesting - the syntax for qnames is taken from the recommendations
> for XML 1.1 and XML 1.1 namespaces.

[...]

> Qnames are not bNodes.  Given that some other syntaxes use _: for a
> bNodes it can create confusion - to be balanced against following the
> XML token definitions.
> 
> 	Andy

Yes, agreed, interesting.  The intent was probably not to allow bnodes via
this path, but the divergence between literal in the grammar and literals
in RDF serves to really muddy the waters - if a literal can be a URI
reference then why can't a QName be a bnode?

peter

Received on Monday, 8 November 2004 10:38:04 UTC