anchor.diff:              "clearRedo" => T<unit> ^-> T<unit> 
           ]
   
  -    let WindowProxyType = Class "Window"
  -    let MessagePortType = Class "MessagePort"
  +    let Window = Class "Window"
  +    let MessagePort = Class "MessagePort"
   
       let ErrorEvent =
           Class "ErrorEvent"
  
positive.code:             "data" =? T<obj>
              "origin" =? T<string>
              "lastEventId" =? T<string>
              "source" =? WindowProxyType
              "ports" =? Type.ArrayOf(MessagePortType)
              "initMessageEvent" => T<string> * T<bool> * T<bool> * T<obj> * T<string> * T<string> * WindowProxyType * Type.ArrayOf(MessagePortType) ^-> T<unit>
                  |> Obsolete
          ]
  
      let MessagePort =
          MessagePortType
          |+> Instance [
              "postMessage" => T<obj> * Type.ArrayOf(MessagePortType) ^-> T<unit>
              "start" => T<unit> ^-> T<unit>
              "close" => T<unit> ^-> T<unit>
              "onmessage" =@ MessageEvent ^-> T<unit>
          ]
  
      let Navigator =
          Class "Navigator" 
  
negative.code:             "NaN" =? T<double> |> WithGetterInline "NaN"
              "Infinity" =? T<double> |> WithGetterInline "Infinity"
              "undefined" =? T<obj> |> WithGetterInline "undefined"
              "eval" => T<string>?expr ^-> T<obj> |> WithInline "eval($expr)"
              "parseInt" => T<string>?str * !?T<int>?radix ^-> T<int> |> WithInline "parseInt($str, $radix)"
              "parseFloat" => T<string>?str ^-> T<double> |> WithInline "parseFloat($str)"
              "isNaN" => T<obj>?number ^-> T<bool> |> WithInline "isNaN($number)"
              "isFinite" => (T<int> + T<float>)?number ^-> T<bool> |> WithInline "isFinite($number)"
              "decodeURI" => T<string>?str ^-> T<string> |> WithInline "decodeURI($str)"
              "decodeURIComponent" => T<string>?str ^-> T<string> |> WithInline "decodeURIComponent($str)"
              "encodeURI" => T<string>?str ^-> T<string> |> WithInline "encodeURI($str)"
              "encodeURIComponent" => T<string>?str ^-> T<string> |> WithInline "encodeURIComponent($str)"
          ]
          |> ignore
  
  module WebWorkers =
  
  