anchor.diff:              r <- rn
               i <- i + 1
           else
  -            failwith ("Invalid server reply. Failed to find type: " + n)
  +            // The class is not present on the client,
  +            // it could have been pruned by the bundling.
  +            r <- JS.Undefined
  +            i <- k
       r
   
   /// Does a shallow generic mapping over an object.
  
positive.code: [<JavaScript>]
  [<Require(typeof<Resource>)>]
  let Activate<'T> (json: obj) : 'T =
      let types = As<obj[]> ((?) json "$TYPES")
      for i = 0 to types.Length - 1 do
          types.[i] <- lookup (As types.[i])
      let rec decode (x: obj) : obj =
  
negative.code:                 if JS.InstanceOf x JS.Global?Array then
                      shallowMap decode x
                  else
                      let o = shallowMap decode (x?("$V"))
                      let ti = x?("$T")
                      if ti ===. JS.Undefined
                          || (As<Array<obj>> types).[ti] ===. JS.Undefined
                      then o
                      else
                          let r = JS.New (As<Array<obj>> types).[ti]
                          JS.ForEach o (fun k -> r?(k) <- o?(k); false)
                          r
              | _ ->
                  x
      As (decode (json?("$DATA")))
  
  