[Bug 4912] Allow empty unions

http://www.w3.org/Bugs/Public/show_bug.cgi?id=4912

           Summary: Allow empty unions
           Product: XML Schema
           Version: 1.1 only
          Platform: Macintosh
        OS/Version: All
            Status: NEW
          Keywords: needsDrafting
          Severity: normal
          Priority: P2
         Component: Datatypes: XSD Part 2
        AssignedTo: cmsmcq@w3.org
        ReportedBy: cmsmcq@w3.org
         QAContact: www-xml-schema-comments@w3.org


XSDL 1.0 required unions to have at least two member types.

Revisions for XSDL 1.0 changed that to require only one; it
won't be a common idiom, but there might be reasons to need
to do it.

In connection with the definition of the xsd:error type, which
is defined as an empty group (so that it has no valid instances),
the Working Group decided on 27 July 2007 to remove the requirement
that groups have at least one member type.  That change has been
made in Structures, and a corresponding change must be made in
Datatypes.

Since the WG has already decided essentially what to do, I'm setting
the keyword of this issue to 'needsDrafting'.

Received on Friday, 3 August 2007 18:56:56 UTC