[Bug 1766] New: [FS] technical: 7.2.13 The fn:subsequence function: tighter typing

http://www.w3.org/Bugs/Public/show_bug.cgi?id=1766

           Summary: [FS] technical: 7.2.13 The fn:subsequence function:
                    tighter typing
           Product: XPath / XQuery / XSLT
           Version: Last Call drafts
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: normal
          Priority: P2
         Component: Formal Semantics
        AssignedTo: simeon@us.ibm.com
        ReportedBy: jmdyck@ibiblio.org
         QAContact: public-qt-comments@w3.org


7.2.13 The fn:subsequence function

"If the type of the input expression has zero or more items, then
fn:subsequence, when selecting the first item, has zero-or-one of the
prime type of the input type."
    It seems to me you could conclude the same thing regardless of which
    item was being selected. That is, replace rules 3 and 4 with

        statEnv |- Expr1 : Type1         quantifier(Type1) in { * }
        statEnv |- Expr2 : xs:double
        -----------------------------------------------------------
        statEnv |- fn:subsequence(Expr1, Expr2, 1) : prime(Type1) ?

    Also, how about:

        statEnv |- Expr1 : Type1         quantifier(Type1) in { 1, + }
        statEnv |- Expr2 : xs:double     not(Expr2 = 1)
        -----------------------------------------------------------
        statEnv |- fn:subsequence(Expr1, Expr2, 1) : prime(Type1) ?

Received on Tuesday, 19 July 2005 23:56:11 UTC