[Bug 1401] New: Use substitution groups to improve usability

http://www.w3.org/Bugs/Public/show_bug.cgi?id=1401

           Summary: Use substitution groups to improve usability
           Product: XPath / XQuery / XSLT
           Version: Last Call drafts
          Platform: PC
        OS/Version: Windows 2000
            Status: NEW
          Severity: normal
          Priority: P2
         Component: XQueryX
        AssignedTo: jim.melton@acm.org
        ReportedBy: holstege@mathling.com
         QAContact: public-qt-comments@w3.org


Use substitutionGroups to make the syntax easier to work with
both with respect to selectors, by eliminating need for xsi:type,
nd for humans.

There are three places in the existing schema where this might apply:
(1) For expressions, to eliminate the need for xsi:type
    This is largely a matter of turning named complex types into 
    elements. See xqx.newschema1.xsd and xq.ex1.xml
(2) For steps in path expressions. This amounts to converting the simple
    type enumeration into a collection of elements.
    See xqx.newschema2.xsd and xq.ex2.xml
(3) For operators. This involves converting some types to elements and
    various enumerations to elements. Since some of the operator names
    are non valid as element names, names need to be created for these
    cases. See xqx.newschema3.xsd and xq.ex3.xml
        
(1) and (2) aren't necessary to get rid of xsi:type, but they do provide
for a more direct syntax. One could go even further on (c) and put the
operators into the "op:" namespace:, which might assist in automatic
mapping from XQuery grammar. 

See schemas and examples at http://lists.w3.org/Archives/Member/w3c-archive/
2005May/0068.html

Received on Friday, 13 May 2005 17:14:18 UTC