anchor.diff:                      if pi <> null then
                           let obj =
                               match t.Name with
  -                            | "String" -> s :> System.Object
  -                            | "Int32" -> s |> int :> System.Object
  -                            | "Double" -> s |> double :> System.Object
  -                            | "DateTime" -> Convert.ToDateTime(s) :> System.Object
  -                            | "TimeSpan" -> TimeSpan.Parse(s) :> System.Object
  -                            | "Boolean" -> Convert.ToBoolean(s) :> System.Object
  +                            | "String" -> s :> obj
  +                            | "Int32" -> s |> int :> obj
  +                            | "Double" -> s |> double :> obj
  +                            | "DateTime" -> Convert.ToDateTime(s) :> obj
  +                            | "TimeSpan" -> TimeSpan.Parse(s) :> obj
  +                            | "Boolean" -> Convert.ToBoolean(s) :> obj
                               | "Color"  -> ColorTypeConverter().ConvertFrom(s)
                               | "Font"   -> FontTypeConverter().ConvertFrom(s)
                               | "Thickness" -> ThicknessTypeConverter().ConvertFrom(s)
  
positive.code:                 | _ -> null
  
  
          member this.LoadView(el:XElement) =
              match el.Name.LocalName with
              // layout 
              | "AbsoluteLayout" -> this.CreateAbsoluteLayout(el)
              | "ContentView" -> this.CreateContentView( el )
              | "Frame" -> this.CreateFrame( el )
              | "ScrollView" -> this.CreateScrollView( el )
              | "StackLayout" -> this.CreateLayout( el, new StackLayout())
              | "RelativeLayout" -> this.CreateLayout( el, new RelativeLayout())
              | "Grid" -> this.CreateGrid(el)
              // view 
              | "ActivityIndicator" -> this.CreateWidget( el, new ActivityIndicator())
              | "BoxView" -> this.CreateWidget( el, new BoxView())
              | "Button" -> this.CreateWidget( el, new Button())
              | "DatePicker" -> this.CreateWidget( el, new Xamarin.Forms.DatePicker())
              | "Image" -> this.CreateWidget( el, new Xamarin.Forms.Image())
              | "Editor" -> this.CreateWidget( el, new Xamarin.Forms.Editor())
              | "Entry" -> this.CreateWidget( el, new Xamarin.Forms.Entry())
              | "Label" -> this.CreateWidget( el, new Xamarin.Forms.Label())
              | "ListView" -> this.CreateWidget( el, new Xamarin.Forms.ListView())
              | "OpenGLView" -> this.CreateWidget( el, new Xamarin.Forms.OpenGLView())
              | "Picker" -> this.CreateWidget( el, new Xamarin.Forms.Picker())
              | "ProgressBar" -> this.CreateWidget( el, new Xamarin.Forms.ProgressBar())
              | "SearchBar" -> this.CreateWidget( el, new Xamarin.Forms.SearchBar())
              | "Slider" -> this.CreateWidget(el, new Slider())
              | "Stepper" -> this.CreateWidget( el, new Xamarin.Forms.Stepper())
              | "Switch" -> this.CreateWidget( el, new Xamarin.Forms.Switch())
              | "TableView" -> this.CreateWidget( el, new Xamarin.Forms.TableView())
              | "WebView" -> this.CreateWidget( el, new Xamarin.Forms.WebView())
              | _ -> null
          
          static member LoadXaml(xaml:string) = 
              let doc = XDocument.Load( new StringReader(xaml))
  
negative.code: open Moonmile.XFormsTypeConv
  
  module XForms =
      
      /// XElement の拡張メソッド
      type XElement with
          member this.Children 
  