[Bug 5250] Prefix as part of xs:QName value space

http://www.w3.org/Bugs/Public/show_bug.cgi?id=5250

           Summary: Prefix as part of xs:QName value space
           Product: XML Schema
           Version: 1.1 only
          Platform: PC
        OS/Version: Windows XP
            Status: NEW
          Severity: normal
          Priority: P2
         Component: Datatypes: XSD Part 2
        AssignedTo: cmsmcq@w3.org
        ReportedBy: mike@saxonica.com
         QAContact: www-xml-schema-comments@w3.org


XDM varies the mapping from lexical space defined in XML Schema 1.0 in two
ways: by retaining the timezone information from dates and times, and by
retaining the prefix from QNames and NOTATIONs.

XML Schema 1.1 fixes the first problem by keeping the timezone as part of the
value and then ignoring it when doing equality matching.

It would seem to be useful to adopt the same strategy to fix the second
problem: retain the prefix as part of the value space for xs:QName and
xs:NOTATION, but take no account of it in the equality relation.

I realize this is related to a number of other open issues concerning QNames
(search Bugzilla for QName in Schema Part 2). My general feeling from a quick
scan of these issues is that this change will not make any of those known
problems any harder to solve, and may make some of them easier.