anchor.diff:      let rec messageLoop currentMessage = async {
           let! msg = inbox.Receive() // get the message
           
  -        let currentState = getState currentMessage // get the current state
  -        let newState = getState msg // get the state of the message
  +        let currentState = postMessage currentMessage // get the current state
  +        let newState = postMessage msg // get the state of the message
           
           match msg with
           | Reply (i, a) ->
  
positive.code: 
  // Async with continuations
  
  let fetchGitHubAsync url = async {
      try
          let uri = new System.Uri(url)
          let webClient = new WebClient()
  
negative.code: }
  
  Async.StartWithContinuations (
      fetchHtml "http://google.com",
      (fun _ -> printfn "success"),
      (fun _ -> printfn "not success"),
      (fun _ -> printfn "canceled"))
  
  [|"http://github.com"; "http://fsharp.org"; "http://stackoverflow.com"|]
  
  let v =
      [|"http://github.com"; "http://fsharp.org"; "http://stackoverflow.com"|]
      |> Array.map fetchHtml
      |> Async.Parallel
      |> Async.RunSynchronously
  
  // *********************************
  // Mailbox Processors/Agents
  