anchor.diff:          <*> Piglet.Yield init.gender
           <*> Piglet.Yield init.comments
           <*> Piglet.Yield init.participates
  -        <*> Piglet.ManyInit init.friends "" (fun f ->
  -            Piglet.Yield f
  -            |> V.Is V.NotEmpty "A friend with no name?"
  -            |> NotANumber)
  +        <*> Piglet.ManyInit init.friends { firstName = ""; lastName = "" } Name
           |> Piglet.TransmitReader
           |> Piglet.WithSubmit
           |> Piglet.Run (fun u ->
  
positive.code:     type Gender = Male | Female
  
      type User =
          { name: Name; age: int; gender: Gender; comments: string; participates: bool; friends: string[] }
  
          [<JavaScript>]
          static member Pretty u =
  
negative.code:             gender = Model.Male
              comments = "Blah blah blah"
              participates = true
              friends =
                  [|
                      { firstName = "Ernesto"; lastName = "Rodriguez" }
                      { firstName = "Loic"; lastName = "Denuziere" }
                  |]
          }
      ViewModel.User initUser
      |> Piglet.Render View.User