[Bug 2735] Need for exact semantics in casting string to decimal

http://www.w3.org/Bugs/Public/show_bug.cgi?id=2735

           Summary: Need for exact semantics in casting string to decimal
           Product: XPath / XQuery / XSLT
           Version: Candidate Recommendation
          Platform: PC
        OS/Version: Windows XP
            Status: NEW
          Severity: normal
          Priority: P2
         Component: Functions and Operators
        AssignedTo: ashok.malhotra@oracle.com
        ReportedBy: chamberl@almaden.ibm.com
         QAContact: public-qt-comments@w3.org


The following change is requested in F&O Section 17.1.1, "Casting from 
xs:string and xdt:untypedAtomic", Paragraph 6:

Old text: "In casting to numerics, if the value is too large or too small to be 
accurately represented by the implementation, it is handled as an overflow or 
underflow as defined in Section 6.2, Operators on Numeric Values.

Proposed new text: "In casting to xs:decimal, if the value cannot be accurately 
represented by the implementation, an error is raised [err:FOAR0002], In 
casting to numeric types other than xs:decimal, if the value is too large or 
too small to be accurately represented by the implementation, it is handled as 
an overflow or underflow as defined in Section 6.2, Operators on Numeric Values.

Reason for change: These rules govern the interpretation of literals in 
queries. We believe that users have an expectation that decimal literals will 
be interpreted exactly and not rounded off. For example, if a user writes the 
decimal literal 1.00000...00001 which cannot be accurately represented by the 
implementation due to lack of precision, the implementation should alert the 
user by an error code rather than simply rounding the literal to 1.

Received on Friday, 20 January 2006 20:00:23 UTC