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Problem with the "rdf" namespaces in RDF Model & Syntax

From: John Cowan <jcowan@reutershealth.com>
Date: Fri, 21 Jul 2000 12:47:03 -0400
Message-ID: <39787E87.546981C4@reutershealth.com>
To: www-rdf-comments@w3.org, xml-dev@xml.org
Jonathan Borden wrote (on xml-dev):

>     In fact, the RDF syntax spec makes (IHMO)  the erroneous assumption that
> attributes inherit the namespace of the enclosing element (witness the use
> of <rdf:y about="..."> rather than <rdf:y rdf:about="...">

So it does.  In particular, about and rdf:about, parseType and rdf:parseType,
resource and rdf:resource, etc. are both used throughout the examples in RDF Model
& Syntax.  The intent seems to have been to use the rdf: prefix on these
reserved attributes only where the (implicit or explicit) prefix of the
element was other than rdf:.

However, this is not what the Namespace Rec prescribes.  Unprefixed attributes
belong to the (sub)namespace defined by the single element type to which they
are attached, *not* to the namespace to which the element itself belongs.
Thus rdf:about and about are in principle different attributes.
Applications of the Namespace Rec may or may not distinguish between them.
RDF M&S is silent on this point.

The BNF syntax seems to allow only about, parseType, resource, ... as attribute
names, unless the statement in clause 2.2. that "[a]ll syntactic flexibilities
of XML are also implicitly included" is meant to silently cover the extension
to rdf:about etc.

If the extension to rdf:about, etc. is meant to be allowed, then an erratum
extending clause 6 to explicitly permit it should issue, either narrowly like
this:

	The reserved attributes about, aboutEach, aboutEachPrefix,
	bagID, ID, parseType, resource, and type may appear either
	without any prefix or with a prefix bound to the
	"http://www.w3.org/1999/02/22-rdf-syntax-ns#" namespace.

or more broadly (applying beyond the rdf: namespace itself) like this:

	Attributes without a prefix are treated by RDF as if they
	belonged to the same namespace as the element in which they
	appear.

If the extension is *not* meant to be allowed, then uses of rdf:(reserved-attribute)
in the various examples (including but not limited to those in clauses
2.2.2, 7.3, 7.5) are in error, and an erratum should issue that corrects them.
In addition, there may be further errata where an unprefixed attribute
name has been used in an element lacking an rdf: prefix.

-- 

Schlingt dreifach einen Kreis um dies! || John Cowan <jcowan@reutershealth.com>
Schliesst euer Aug vor heiliger Schau,  || http://www.reutershealth.com
Denn er genoss vom Honig-Tau,           || http://www.ccil.org/~cowan
Und trank die Milch vom Paradies.            -- Coleridge (tr. Politzer)
Received on Friday, 21 July 2000 12:48:27 GMT

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