i am having a problem with rodAssignHandleToParameter

this is my code

procedure(createALPHA(cv w l)
  let( (rectRodObj)
  ;; create a rectangle on metal1 with x & y dimensions set by w & l
  rectRodObj = rodCreateRect(
      ?name     "myRect"
      ?cvId     cv
      ?layer    list("ALPHA" "drawing")
      ?width    w
      ?length   l
      ?origin   list(0 0)
  )
  ;; create labels to show the w and l parameters
  ;; create a stretch handle for the width, in the X dimension, it
  ;; will display as "width = <value>" and change by 0.1 increments
  rodAssignHandleToParameter(
    ?parameter          "w"
    ?rodObj             rectRodObj
    ?handleName         "centerRight"
    ?stretchDir         "X"
    ?displayName        "width"
    ?displayExpression  "w"
    ?updateIncrement    0.2
  ); rodAssignHandleToParameter
  ); let
); procedure CCScreateBoxAndLabels
pcDefinePCell(
  list(ddGetObj("adhillib") "gp2_path1" "layout")
   (
    (rows 1)
    (cols 1)
    (finger_width 0.10)
   )
     
  let(((cv pcCellView) paramObj awidth alength bBox) 
  paramObj = dbCreateParamInstByMasterName(cv "adhillib" "gp2_path" "layout" "inst1"
   list(0 0)
   "R0"
   1
   list(
    list("rows" "float" rows)
    list("cols" "float" cols)
    list("finger_width" "float" finger_width))
   )
  bBox = paramObj~>bBox

awidth  = xCoord(upperRight(bBox)) - xCoord(lowerLeft(bBox))
alength = yCoord(upperRight(bBox)) - yCoord(lowerLeft(bBox))
println(awidth)
createALPHA(cv awidth alength)
cols = awidth/0.2
)
  )
 but i am getting the error

*WARNING* rodAssignHandleToParameter: w is an invalid parameter
*WARNING* rodAssignHandleToParameter: command failed

I am trying to use the handle on rodrectobj with an alpha layer to extend the pcell within

Adhil