[Bug 2461] [XQuery] Data model conformance

http://www.w3.org/Bugs/Public/show_bug.cgi?id=2461

           Summary: [XQuery] Data model conformance
           Product: XPath / XQuery / XSLT
           Version: Candidate Recommendation
          Platform: PC
        OS/Version: Windows XP
            Status: NEW
          Severity: normal
          Priority: P2
         Component: XQuery
        AssignedTo: chamberl@almaden.ibm.com
        ReportedBy: mike@saxonica.com
         QAContact: public-qt-comments@w3.org


The XQuery spec (section 5.3) says "A conforming implementation may choose
to claim conformance to [Contruction from an Infoset|PSVI]".

It doesn't actually say what an implementation has to do in order for such a
claim to be valid.

The answer to the question isn't obvious, because PSVIs and Infosets don't
have any real existence: they are abstract models rather than concrete data
structures.

As an implementor I can attempt an argument along the following lines:

* I can take a JDOM as input
* there is a defined mapping from JDOM to the Infoset
* If I take a JDOM as input, then the Infoset that it represents has been
converted to XDM in a way that's consistent with the XDM specification

This works reasonably well for Infoset, because there's a number of
well-known XML document representations with a defined mapping to the
Infoset. Even here there's wriggle room however. If JDOM doesn't define a
mapping to the InfoSet, can I define the mapping myself, and thus claim
conformance?

WIth PSVI it's altogether more difficult. My product doesn't allow you to
supply a PSVI as input, other than a PSVI subset represented in a
proprietary format implemented only by my own product. It does allow you to
supply a source XML file and a schema as input, and produces results
consistent with validating that document against that schema and converting
the resulting PSVI to the XDM. Can I claim conformance with "Construction
from a PSVI" or not?

I don't know what the conformance section should say, but it's meaningless
if it says that it's entirely up to the implementor whether they choose to
claim conformance or not.

Michael Kay

previously raised at
http://lists.w3.org/Archives/Member/w3c-xml-query-wg/2005Oct/0036.html

Received on Friday, 4 November 2005 16:51:49 UTC