[Bug 3250] definition of precisionDecimal

http://www.w3.org/Bugs/Public/show_bug.cgi?id=3250

           Summary: definition of precisionDecimal
           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


QT approved comment

While 3.3.3.1 goes to some lengths to give a respectably formal definition of
the value space of xs:decimal, 3.3.4.1 makes no serious attempt to do so for
xs:precisionDecimal. Part of the problem, I think, is that there is a hint that
the data type has "floating point" characteristics, which isn't actually
carried through in the definition. If the value space contains all decimal
numbers with trailing zeros considered significant, a "floating-point"
implementation is likely to restrict this infinite space to a subset containing
say N consecutive non-zero digits anywhere, while a "fixed-point"
implementation is likely to restrict it to a subset containing N digits before
and F digits after the decimal point. These two implementations have very
different characteristics, but the spec doesn't appear to prescribe one or the
other. The only real clue that the former is expected comes from the definition
of the totalDigits facet.

Received on Tuesday, 9 May 2006 10:58:38 UTC