anchor.diff:  
       let CurrentLevel () = stack.[0]
   
  -    let popDownTo (targetLevel : int) (expressions : IList<IokeObject>) =
  +    let popDownTo targetLevel (expressions : IList<IokeObject>) =
           let rec helper () =
               match stack with
                   | []  -> ()
  
positive.code: 
      let isInverted (ms:IokeObject) = invertedOperatorTable.Contains(ms)
  
      let (|Operator|InvertedOperator|OtherOp|) (sym:IokeObject) =
          if operatorTable.Contains(sym) then
              Operator(Number.GetValue(operatorTable.[sym]).intValue())
          else
  
negative.code:             else
                  OtherOp
  
      let levelForOp (messageName : string) messageSymbol msg =
          match messageSymbol with
              | Operator(prec) -> prec
              | InvertedOperator(prec) -> prec
  