- From: <noah_mendelsohn@us.ibm.com>
- Date: Tue, 5 Aug 2008 22:49:20 -0400
- To: John Bradley <john.bradley@wingaa.com>
- Cc: "Booth, David (HP Software - Boston)" <dbooth@hp.com>, "Henry S. Thompson" <ht@inf.ed.ac.uk>, www-tag@w3.org
John Bradely writes: > A IRI is NOT a URI, it would be WRONG to use a IRI in an XML > document for name-spacing. > > The XML specs are clear and unambiguous use a URI. Well, they do seem to me to be clear, but I read them differently than you do I'm afraid ;-). From the XML Namespaces 1.1 Recommendation [1]: "Abstract: XML namespaces provide a simple method for qualifying element and attribute names used in Extensible Markup Language documents by associating them with namespaces identified by IRI references." and indeed the formal definition [2] says: "[Definition: An XML namespace is identified by an IRI reference [RFC3987]; element and attribute names may be placed in an XML namespace using the mechanisms described in this specification. ]" Regarding schemas to validate such namespace names, note that XML Schema 1.0 Datatypes anticipated IRIs by defining the xsd:anyURI type [3] in a manner that effectively allows for IRIs (that's why there's the somewhat confusing reference to XLink mapping rules in the 2nd paragraph); XML Schema 1.1 formalizes the connection [4] now that IRIs are "official", stating: "[Definition:] anyURI represents an Internationalized Resource Identifier Reference (IRI). An anyURI value can be absolute or relative, and may have an optional fragment identifier (i.e., it may be an IRI Reference). This type should be used when the value fulfills the role of an IRI, as defined in [RFC 3987] or its successor(s) in the IETF Standards Track." When writing a schema to validate namespace-qualified content, so-called "targetNamespace" attributes of type xsd:anyURI are used to specify the namespaces to be matched. So, both the specifications for namespaces in XML content, and the specifications for the schemas to validate that content quite explicitly allow for IRIs. Noah [1] http://www.w3.org/TR/xml-names11/ [2] http://www.w3.org/TR/xml-names11/#dt-namespace [3] http://www.w3.org/TR/2004/PER-xmlschema-2-20040318/#anyURI [4] http://www.w3.org/TR/xmlschema11-2/#anyURI -------------------------------------- Noah Mendelsohn IBM Corporation One Rogers Street Cambridge, MA 02142 1-617-693-4036 --------------------------------------
Received on Wednesday, 6 August 2008 02:48:39 UTC