anchor.diff:                              ch.Reply()
                               return ()                            
                           | Process (x,continuation) -> 
  -                            //printfn "PROCESS"
  +                            //printfn "PROCESS start"
                               let r = f x
                               continuation r
  +                            //printfn "Process End"
                               return! loopW n
                           | x -> 
                               printfn "unexpected message for Worker: %A" x
  
positive.code: let rows = 1100
  let columns = 1100
  
  type Master<'d,'r,'fr>((*config:MasterConfig,*) workers:array<Worker<'d,'r>>, fill: 'd -> Option<'d>, bufs:ResizeArray<'d>, postProcessF:Option<'r->'fr>) 
      as this =        
      
      let isDataEnd = ref false
      let reader = new Reader<_>(fill)
  
negative.code:                                             dataManager.Enq b.Value)
                                  else 
                                      isDataEnd := true
                          if inbox.CurrentQueueLength > 0
                          then
                              let! msg = inbox.Receive()
                              match msg with
                              | Die ch ->
                                  dataManager.Die()                                
                                  workers |> Array.iter (fun w -> w.Die())
                                  match postprocessor with Some p -> p.Die() | None -> ()
  