anchor.diff:              "onloadeddata" =@ f
               "onloadedmetadata" =@ f
               "onloadstart" =@ f
  +            "onloadend" =@ f
               "onmessage" =@ f
               "onmousedown" =@ f
               "onmousemove" =@ f
               "onmouseout" =@ f
               "onmouseover" =@ f
               "onmouseup" =@ f
  +            "onmouseenter" =@ f
  +            "onmouseleave" =@ f
               "onmousewheel" =@ f
               "onoffline" =@ f
               "ononline" =@ f
  
positive.code:                 General.MessageEvent
                  General.MessagePort
                  General.Navigator
                  General.UndoManager
                  General.Window
                  TypedArrays.DataView.Class
  
negative.code:             "pathname" =@ T<string>
              "search" =@ T<string>
              "hash" =@ T<string>
              "origin" =? T<string>
              "username" =@ T<string>
              "password" =@ T<string>
  
          ]
  
      let UndoManager =
          Class "UndoManager"
          |+> Instance [
              "length" =? T<int>
              "position" =? T<int>
              "undo" => T<unit> ^-> T<unit>
              "redo" => T<unit> ^-> T<unit>
              "remove" => T<int> ^-> T<unit>
              "clearUndo" => T<unit> ^-> T<unit> 
              "clearRedo" => T<unit> ^-> T<unit> 
  