anchor.diff:                           yield div [ClassName "input-group"][
                                yield span [ClassName "input-group-addon"] [span [ClassName "glyphicon glyphicon-user"] [] ]
                                yield input [ 
  +                                     Key ("Author_" + model.NewBookId.ToString())
                                        HTMLAttr.Type "text"
                                        Name "Author"
                                        DefaultValue (U2.Case1 model.NewBook.Authors)
  
positive.code:                          yield div [ClassName "input-group"] [
                               yield span [ClassName "input-group-addon"] [span [ClassName "glyphicon glyphicon glyphicon-pencil"] [] ]
                               yield input [ 
                                      HTMLAttr.Type "text"
                                      Name "Link"
                                      DefaultValue (U2.Case1 model.NewBook.Link)
  
negative.code:                         yield div [ClassName "input-group"] [
                               yield span [ClassName "input-group-addon"] [span [ClassName "glyphicon glyphicon-pencil"] [] ]
                               yield input [
                                       Key ("Title_" + model.NewBookId.ToString())
                                       HTMLAttr.Type "text"
                                       Name "Title"
                                       DefaultValue (U2.Case1 model.NewBook.Title)
  