Merge pull request #978 from ronnieholm/master

Remove warnings and make code more idiomatic F#

FSharpExample/Program.fs

@@ -1,506 +1,448 @@
-// Learn more about F# at http://fsharp.org
-
-open Terminal.Gui
-open System
-open System.Collections.Generic
+open System
 open System.Diagnostics
 open System.Globalization
-open System.Reflection
+open System.IO
 open NStack
+open Terminal.Gui
+
+let ustr (x: string) = ustring.Make(x)
+let mutable ml2 = Unchecked.defaultof<Label>
+let mutable ml = Unchecked.defaultof<Label>
+let mutable menu = Unchecked.defaultof<MenuBar>
+let mutable menuKeysStyle = Unchecked.defaultof<CheckBox>
+let mutable menuAutoMouseNav = Unchecked.defaultof<CheckBox>
+
+type Box10x (x: int, y: int) =
+    inherit View (Rect(x, y, 20, 10))
+    let w = 40
+    let h = 50
+
+    new () =
+        new Box10x ()
+
+    member _.GetContentSize () =
+        Size (w, h)
+
+    member _.SetCursorPosition (_ : Point) =
+        raise (NotImplementedException())
 
-type Demo() = class end
-    let ustr (x:string) = ustring.Make(x)
-    let mutable ml2 = Unchecked.defaultof<Label>
-    let mutable ml = Unchecked.defaultof<Label>
-    let mutable menu = Unchecked.defaultof<MenuBar>
-    let mutable menuKeysStyle = Unchecked.defaultof<CheckBox>
-    let mutable menuAutoMouseNav = Unchecked.defaultof<CheckBox>
-
-    type Box10x(x : int, y : int) =
-        inherit View(new Rect(x, y, 20, 10))
-        let w = 40
-        let h = 50
-        member val WantCursorPosition = Unchecked.defaultof<System.Boolean> with get, set
-        new() as _this =
-            (Box10x())
-            then
-            ()
-        member this.GetContentSize() =
-            new Size(w, h)
-        member this.SetCursorPosition(pos : Point) =
-            raise (new NotImplementedException())
-        override this.Redraw(region : Rect) =
-            Application.Driver.SetAttribute (Application.Current.ColorScheme.Focus)
-            do
-            let mutable (y : int) = 0
-            while (y < h) do
-            this.Move (0, y)
-            Application.Driver.AddStr (ustr (y.ToString()))
-            do
-            let mutable (x : int) = 0
-            while (x < w - (y.ToString ()).Length) do
-                if (y.ToString ()).Length < w
-                then Application.Driver.AddStr (ustr " ")
-                x <- x + 1
-            x
-            y <- y + 1
-            y
-            ()
-
-    type Filler(rect : Rect) =
-        inherit View(rect)
-        new() as _this =
-            (Filler ())
-            then
-            ()
-        override this.Redraw(region : Rect) =
-            Application.Driver.SetAttribute (Application.Current.ColorScheme.Focus)
-            let mutable f = this.Frame
-            do
-            let mutable (y : int) = 0
-            while (y < f.Width) do
-            this.Move (0, y)
-            do
-            let mutable (x : int) = 0
-            while (x < f.Height) do
-                let mutable (r : Rune) = Unchecked.defaultof<Rune>
-                match (x % 3) with
+    override this.Redraw (_: Rect) =
+        Application.Driver.SetAttribute Application.Current.ColorScheme.Focus
+        do
+        let mutable y = 0
+        while y < h do
+        this.Move (0, y)
+        Application.Driver.AddStr (ustr (string y))
+        do
+        let mutable x = 0
+        while x < w - (y.ToString ()).Length do
+            if (string y).Length < w
+            then Application.Driver.AddStr (ustr " ")
+            x <- x + 1
+        y <- y + 1
+
+type Filler (rect: Rect) =
+    inherit View(rect)
+    new () =
+        new Filler ()
+
+    override this.Redraw (_: Rect) =
+        Application.Driver.SetAttribute Application.Current.ColorScheme.Focus
+        let mutable f = this.Frame
+        do
+        let mutable y = 0
+        while y < f.Width do
+        this.Move (0, y)
+        do
+        let mutable x = 0
+        while x < f.Height do
+            let r =
+                match x % 3 with
                 | 0 ->
-                    Application.Driver.AddRune ((Rune ((y.ToString ()).ToCharArray (0, 1)).[0]))
-                    if y > 9
-                    then Application.Driver.AddRune ((Rune ((y.ToString ()).ToCharArray (1, 1)).[0]))
-                    r <- (Rune '.')
-                | 1 ->
-                    r <- (Rune 'o')
-                | _ ->
-                    r <- (Rune 'O')
-                Application.Driver.AddRune (r)
-                x <- x + 1
-            x
-            y <- y + 1
-            y
-            ()
-
-    let ShowTextAlignments() =
-        let okButton = new Button(ustr "Ok", true)
-        okButton.add_Clicked(Action(Application.RequestStop))
-        let cancelButton = new Button(ustr "Cancel", true)
-        cancelButton.add_Clicked(Action(Application.RequestStop))
-
-        let mutable container = new Dialog(ustr "Text Alignments", 50, 20, okButton, cancelButton)
-        let mutable (i : int) = 0
-        let mutable (txt : string) = "Hello world, how are you doing today"
-        container.Add (
-            new Label (new Rect (0, 1, 40, 3), ustr ((sprintf "%O-%O" (i + 1)) txt), TextAlignment = TextAlignment.Left),
-            new Label (new Rect (0, 3, 40, 3), ustr ((sprintf "%O-%O" (i + 2)) txt), TextAlignment = TextAlignment.Right),
-            new Label (new Rect (0, 5, 40, 3), ustr ((sprintf "%O-%O" (i + 3)) txt), TextAlignment = TextAlignment.Centered),
-            new Label (new Rect (0, 7, 40, 3), ustr ((sprintf "%O-%O" (i + 4)) txt), TextAlignment = TextAlignment.Justified)
-            )
-        Application.Run (container)
-
-    let ShowEntries(container : View) =
-        let mutable scrollView = new ScrollView (new Rect (50, 10, 20, 8),
-            ContentSize = new Size (20, 50),
+                    Application.Driver.AddRune ((Rune ((string y).ToCharArray (0, 1)).[0]))
+                    if y > 9 then
+                        Application.Driver.AddRune ((Rune ((string y).ToCharArray (1, 1)).[0]))
+                    Rune '.'
+                | 1 -> Rune 'o'
+                | _ -> Rune 'O'
+            Application.Driver.AddRune r
+            x <- x + 1
+        y <- y + 1
+
+let ShowTextAlignments () =
+    let okButton = new Button (ustr "Ok", true)
+    okButton.add_Clicked (Action (Application.RequestStop))
+    let cancelButton = new Button (ustr "Cancel", true)
+    cancelButton.add_Clicked (Action (Application.RequestStop))
+
+    let container = new Dialog (ustr "Text Alignments", 50, 20, okButton, cancelButton)
+    let txt = "Hello world, how are you doing today"
+    container.Add (
+        new Label (Rect(0, 1, 40, 3), ustr ((sprintf "%O-%O" 1) txt), TextAlignment = TextAlignment.Left),
+        new Label (Rect(0, 3, 40, 3), ustr ((sprintf "%O-%O" 2) txt), TextAlignment = TextAlignment.Right),
+        new Label (Rect(0, 5, 40, 3), ustr ((sprintf "%O-%O" 3) txt), TextAlignment = TextAlignment.Centered),
+        new Label (Rect(0, 7, 40, 3), ustr ((sprintf "%O-%O" 4) txt), TextAlignment = TextAlignment.Justified))
+    Application.Run container
+
+let ShowEntries (container: View) =
+    let scrollView = 
+        new ScrollView (Rect (50, 10, 20, 8),
+            ContentSize = Size (20, 50),
             ShowVerticalScrollIndicator = true,
-            ShowHorizontalScrollIndicator = true
-            )
-        scrollView.Add (new Filler(new Rect(0, 0, 40, 40)))
-        let mutable scrollView2 = new ScrollView (new Rect (72, 10, 3, 3),
-            ContentSize = new Size (100, 100),
+            ShowHorizontalScrollIndicator = true)
+    scrollView.Add (new Filler (Rect (0, 0, 40, 40)))
+    let scrollView2 = 
+        new ScrollView (Rect (72, 10, 3, 3),
+            ContentSize = Size (100, 100),
             ShowVerticalScrollIndicator = true,
-            ShowHorizontalScrollIndicator = true
-            )
-        scrollView2.Add (new Box10x(0, 0))
-        let mutable progress = new ProgressBar(new Rect(68, 1, 10, 1))
-        let timer = Func<MainLoop, bool> (fun (caller) ->
-            progress.Pulse ();
-            true)
-
-        Application.MainLoop.AddTimeout (TimeSpan.FromMilliseconds (300.0), timer) |> ignore
-
-        let mutable login = Label (ustr "Login: ",
-            X = Pos.At(3),
-            Y = Pos.At(6)
-            )
-        let mutable password = new Label (ustr "Password: ",
-            X = Pos.Left (login),
-            Y = Pos.Bottom (login) + Pos.At(1)
-            )
-        let mutable loginText = new TextField (ustr "",
-            X = Pos.Right (password),
-            Y = Pos.Top (login),
-            Width = Dim.op_Implicit(40)
-            )
-        let mutable passText = new TextField (ustr "",
+            ShowHorizontalScrollIndicator = true)
+    scrollView2.Add (new Box10x (0, 0))
+    let progress = new ProgressBar (Rect(68, 1, 10, 1))
+    let timer = Func<MainLoop, bool> (fun _ ->
+        progress.Pulse ()
+        true)
+
+    Application.MainLoop.AddTimeout (TimeSpan.FromMilliseconds (300.), timer) |> ignore
+
+    let login =
+        new Label (ustr "Login: ",
+            X = Pos.At 3,
+            Y = Pos.At 6)
+    let password =
+        new Label (ustr "Password: ",
+            X = Pos.Left login,
+            Y = Pos.Bottom login + Pos.At 1)
+    let loginText =
+        new TextField (ustr "",
+            X = Pos.Right password,
+            Y = Pos.Top login,
+            Width = Dim.op_Implicit 40)
+    let passText =
+        new TextField (ustr "",
             Secret = true,
-            X = Pos.Left (loginText),
-            Y = Pos.Top (password),
-            Width = Dim.Width (loginText)
-            )
-        let mutable tf = new Button(3, 19, ustr "Ok")
-        container.Add (login, loginText, password, passText,
-            new FrameView (new Rect (3, 10, 25, 6), ustr "Options",
-                [|new CheckBox (1, 0, ustr "Remember me");
-                new RadioGroup (1, 2, [|ustr "_Personal"; ustr "_Company"|])|]
-                ),
-            new ListView (new Rect(59, 6, 16, 4),
-                    [|"First row";
-                    "<>";
-                    "This is a very long row that should overflow what is shown";
-                    "4th";
-                    "There is an empty slot on the second row";
-                    "Whoa";
-                    "This is so cool"|]
-                ),
-            scrollView, scrollView2, tf,
-            new Button(10, 19, ustr "Cancel"),
-            new TimeField(3, 20, DateTime.Now.TimeOfDay),
-            new TimeField(23, 20, DateTime.Now.TimeOfDay, true),
-            new DateField(3, 22, DateTime.Now),
-            new DateField(23, 22, DateTime.Now, true),
-            progress,
-            new Label(3, 24, ustr "Press F9 (on Unix, ESC+9 is an alias) to activate the menubar"),
-            menuKeysStyle,
-            menuAutoMouseNav
-        )
-        container.SendSubviewToBack (tf)
-        ()
-
-    let NewFile() =
-        let okButton = new Button(ustr "Ok", true)
-        okButton.add_Clicked(Action(Application.RequestStop))
-        let cancelButton = new Button(ustr "Cancel", true)
-        cancelButton.add_Clicked(Action(Application.RequestStop))
-
-        let mutable d = new Dialog (ustr "New File", 50, 20, okButton, cancelButton)
-        ml2 <- new Label(1, 1, ustr "Mouse Debug Line")
-        d.Add (ml2)
-        Application.Run (d)
-
-    let GetFileName()=
-        let mutable (fname : string) = Unchecked.defaultof<_>
-        for s in [|"/etc/passwd"; "c:\\windows\\win.ini"|] do
-            if System.IO.File.Exists (s)
-            then
-                fname <- s
-        fname
-
-    let Editor(top : Toplevel) =
-        let mutable tframe = top.Frame
-        let mutable ntop = new Toplevel(tframe)
-        let mutable menu = new MenuBar([|new MenuBarItem(ustr "_File",
-            [|new MenuItem(ustr "_Close", ustring.Empty, (fun () -> Application.RequestStop ()))|]);
-            new MenuBarItem(ustr "_Edit", [|new MenuItem(ustr "_Copy", ustring.Empty, Unchecked.defaultof<_>);
-            new MenuItem(ustr "C_ut", ustring.Empty, Unchecked.defaultof<_>);
-            new MenuItem(ustr "_Paste", ustring.Empty, Unchecked.defaultof<_>)|])|]
-            )
-        ntop.Add (menu)
-        let mutable (fname : string) = GetFileName()
-        let mutable win = new Window (ustr(if fname <> null then fname else "Untitled"),
-            X = Pos.At(0),
-            Y = Pos.At(1),
+            X = Pos.Left loginText,
+            Y = Pos.Top password,
+            Width = Dim.Width loginText)
+    let tf = new Button (3, 19, ustr "Ok")
+    container.Add (login, loginText, password, passText,
+        new FrameView (Rect (3, 10, 25, 6), ustr "Options",
+            [| new CheckBox (1, 0, ustr "Remember me")
+               new RadioGroup (1, 2, 
+                [| ustr "_Personal"; ustr "_Company"|])|]),
+        new ListView (Rect (59, 6, 16, 4),
+                [| "First row"
+                   "<>"
+                   "This is a very long row that should overflow what is shown"
+                   "4th"
+                   "There is an empty slot on the second row"
+                   "Whoa"
+                   "This is so cool" |]),
+        scrollView, scrollView2, tf,
+        new Button (10, 19, ustr "Cancel"),
+        new TimeField (3, 20, DateTime.Now.TimeOfDay),
+        new TimeField (23, 20, DateTime.Now.TimeOfDay, true),
+        new DateField (3, 22, DateTime.Now),
+        new DateField (23, 22, DateTime.Now, true),
+        progress,
+        new Label (3, 24, ustr "Press F9 (on Unix, ESC+9 is an alias) to activate the menubar"),
+        menuKeysStyle,
+        menuAutoMouseNav)
+    container.SendSubviewToBack tf
+
+let NewFile () =
+    let okButton = new Button (ustr "Ok", true)
+    okButton.add_Clicked (Action (Application.RequestStop))
+    let cancelButton = new Button (ustr "Cancel", true)
+    cancelButton.add_Clicked (Action (Application.RequestStop))
+
+    let d = new Dialog (ustr "New File", 50, 20, okButton, cancelButton)
+    ml2 <- new Label (1, 1, ustr "Mouse Debug Line")
+    d.Add ml2
+    Application.Run d
+
+let GetFileName () =
+    let mutable fname = Unchecked.defaultof<_>
+    for s in [| "/etc/passwd"; "c:\\windows\\win.ini" |] do
+        if File.Exists s
+        then fname <- s
+    fname
+
+let Editor (top: Toplevel) =
+    let tframe = top.Frame
+    let ntop = new Toplevel(tframe)
+    let menu = 
+        new MenuBar(
+            [| MenuBarItem (ustr "_File",
+                 [| MenuItem (ustr "_Close", ustring.Empty, (fun () -> Application.RequestStop ())) |]);
+                    MenuBarItem (ustr "_Edit",
+                        [| MenuItem (ustr "_Copy", ustring.Empty, Unchecked.defaultof<_>)
+                           MenuItem (ustr "C_ut", ustring.Empty, Unchecked.defaultof<_>)
+                           MenuItem (ustr "_Paste", ustring.Empty, Unchecked.defaultof<_>) |]) |])
+    ntop.Add menu
+    let fname = GetFileName ()
+    let win = 
+        new Window (
+            ustr (if not (isNull fname) then fname else "Untitled"),
+            X = Pos.At 0,
+            Y = Pos.At 1,
             Width = Dim.Fill (),
-            Height = Dim.Fill ()
-        )
-        ntop.Add (win)
-        let mutable text = new TextView(new Rect(0, 0, (tframe.Width - 2), (tframe.Height - 3)))
-        if fname <> Unchecked.defaultof<_>
-        then text.Text <- ustr (System.IO.File.ReadAllText (fname))
-        win.Add (text)
-        Application.Run (ntop)
-
-    let Quit() =
-        let mutable n = MessageBox.Query (50, 7, ustr "Quit Demo", ustr "Are you sure you want to quit this demo?", ustr "Yes", ustr "No")
-        n = 0
-
-    let Close() =
-        MessageBox.ErrorQuery (50, 7, ustr "Error", ustr "There is nothing to close", ustr "Ok")
-        |> ignore
-
-    let Open() =
-        let mutable d = new OpenDialog (ustr "Open", ustr "Open a file", AllowsMultipleSelection = true)
-        Application.Run (d)
-        if not d.Canceled
-            then MessageBox.Query (50, 7, ustr "Selected File", ustr (String.Join (", ", d.FilePaths)), ustr "Ok") |> ignore
-
-    let ShowHex(top : Toplevel) =
-        let mutable tframe = top.Frame
-        let mutable ntop = new Toplevel(tframe)
-        let mutable menu = new MenuBar([|new MenuBarItem(ustr "_File",
-            [|new MenuItem(ustr "_Close", ustring.Empty, (fun () -> Application.RequestStop ()))|])|])
-        ntop.Add (menu)
-        let mutable win = new Window (ustr "/etc/passwd",
-            X = Pos.At(0),
-            Y = Pos.At(1),
+            Height = Dim.Fill ())
+    ntop.Add win
+    let text = new TextView (Rect(0, 0, (tframe.Width - 2), (tframe.Height - 3)))
+    if fname <> Unchecked.defaultof<_>
+    then text.Text <- ustr (File.ReadAllText fname)
+    win.Add text
+    Application.Run ntop
+
+let Quit () =
+    MessageBox.Query (50, 7, ustr "Quit Demo", ustr "Are you sure you want to quit this demo?", ustr "Yes", ustr "No") = 0
+
+let Close () =
+    MessageBox.ErrorQuery (50, 7, ustr "Error", ustr "There is nothing to close", ustr "Ok")
+    |> ignore
+
+let Open () =
+    let d = new OpenDialog (ustr "Open", ustr "Open a file", AllowsMultipleSelection = true)
+    Application.Run d
+    if not d.Canceled
+        then MessageBox.Query (50, 7, ustr "Selected File", ustr (String.Join (", ", d.FilePaths)), ustr "Ok") |> ignore
+
+let ShowHex (top: Toplevel) =
+    let tframe = top.Frame
+    let ntop = new Toplevel (tframe)
+    let menu = 
+        new MenuBar (
+            [| MenuBarItem (ustr "_File",
+                 [| MenuItem (ustr "_Close", ustring.Empty, (fun () -> Application.RequestStop ())) |]) |])
+    ntop.Add menu
+    let win =
+        new Window (ustr "/etc/passwd",
+            X = Pos.At 0,
+            Y = Pos.At 1,
             Width = Dim.Fill (),
-            Height = Dim.Fill ()
-            )
-        ntop.Add (win)
-        let mutable (fname : string) = GetFileName()
-        let mutable source = System.IO.File.OpenRead (fname)
-        let mutable hex = new HexView (source,
-            X = Pos.At(0),
-            Y = Pos.At(0),
+            Height = Dim.Fill ())
+    ntop.Add win
+    let fname = GetFileName ()
+    let source = File.OpenRead fname
+    let hex = 
+        new HexView (source,
+            X = Pos.At 0,
+            Y = Pos.At 0,
             Width = Dim.Fill (),
-            Height = Dim.Fill ()
-            )
-        win.Add (hex)
-        Application.Run (ntop)
-    
-    type MenuItemDetails() =
-        inherit MenuItem()
-        new(title : ustring, help : string, action : Action) as this =
-            (MenuItemDetails ())
-            then
-                this.Title <- title
-                this.Help <- ustr help
-                this.Action <- action
-        static member Instance(mi : MenuItem) =
-            (mi.GetMenuItem ()) :?> MenuItemDetails
-
-    type MenuItemDelegate = delegate of MenuItemDetails -> MenuItem
-
-    let ShowMenuItem(mi : MenuItemDetails) =
-        let mutable (flags : BindingFlags) = BindingFlags.Public ||| BindingFlags.Static
-        let mutable (minfo : MethodInfo) = typeof<MenuItemDetails>.GetMethod ("Instance", flags)
-        let mutable (mid : Delegate) = Delegate.CreateDelegate (typeof<MenuItemDelegate>, minfo)
-        MessageBox.Query (70, 7, ustr (mi.Title.ToString ()),
-            ustr ((sprintf "%O selected. Is from submenu: %O" (mi.Title.ToString ())) (mi.GetMenuBarItem ())), ustr "Ok")
-        |> ignore
-
-    let MenuKeysStyle_Toggled(e : bool) =
-        menu.UseKeysUpDownAsKeysLeftRight <- menuKeysStyle.Checked
-
-    let MenuAutoMouseNav_Toggled(e : bool) =
-        menu.WantMousePositionReports <- menuAutoMouseNav.Checked
-
-    let Copy() =
-        let mutable (textField : TextField) = menu.LastFocused :?> TextField
-        if textField <> Unchecked.defaultof<_> && textField.SelectedLength <> 0
-        then textField.Copy ()
-        ()
-
-    let Cut() =
-        let mutable (textField : TextField) = menu.LastFocused :?> TextField
-        if textField <> Unchecked.defaultof<_> && textField.SelectedLength <> 0
-        then textField.Cut ()
-        ()
-
-    let Paste() =
-        let mutable (textField : TextField) = menu.LastFocused :?> TextField
-        if textField <> Unchecked.defaultof<_>
-        then textField.Paste ()
-        ()
-
-    let Help() =
-        MessageBox.Query (50, 7, ustr "Help", ustr "This is a small help\nBe kind.", ustr "Ok")
-        |> ignore
-
-    let Load () =
-        MessageBox.Query (50, 7, ustr "Load", ustr "This is a small load\nBe kind.", ustr "Ok")
-        |> ignore
-
-    let Save () =
-        MessageBox.Query (50, 7, ustr "Save ", ustr "This is a small save\nBe kind.", ustr "Ok")
-        |> ignore
-
-    let ListSelectionDemo(multiple : System.Boolean) =
-        let okButton = new Button(ustr "Ok", true)
-        okButton.add_Clicked(Action(Application.RequestStop))
-        let cancelButton = new Button(ustr "Cancel")
-        cancelButton.add_Clicked(Action(Application.RequestStop))
-
-        let mutable d = new Dialog (ustr "Selection Demo", 60, 20, okButton, cancelButton)
-        let mutable animals = new List<string> ()
-        animals.AddRange([|"Alpaca"; "Llama"; "Lion"; "Shark"; "Goat"|])
-        let mutable msg = new Label (ustr "Use space bar or control-t to toggle selection",
-            X = Pos.At(1),
-            Y = Pos.At(1),
-            Width = Dim.Fill () - Dim.op_Implicit(1),
-            Height = Dim.op_Implicit(1)
-            )
-        let mutable list = new ListView (animals,
-            X = Pos.At(1),
-            Y = Pos.At(3),
-            Width = Dim.Fill () - Dim.op_Implicit(4),
-            Height = Dim.Fill () - Dim.op_Implicit(4),
+            Height = Dim.Fill ())
+    win.Add hex
+    Application.Run ntop
+
+type MenuItemDetails () =
+    inherit MenuItem ()
+    new (title: ustring, help: string, action: Action) as this =
+        MenuItemDetails ()
+        then
+            this.Title <- title
+            this.Help <- ustr help
+            this.Action <- action
+
+    static member Instance (mi: MenuItem) =
+        (mi.GetMenuItem ()) :?> MenuItemDetails
+
+type MenuItemDelegate = delegate of MenuItemDetails -> MenuItem
+
+let ShowMenuItem (mi: MenuItemDetails) =
+    MessageBox.Query (70, 7, ustr (mi.Title.ToString ()),
+        ustr ((sprintf "%O selected. Is from submenu: %O" (mi.Title.ToString ())) (mi.GetMenuBarItem ())), ustr "Ok")
+    |> ignore
+
+let MenuKeysStyleToggled (_: bool) =
+    menu.UseKeysUpDownAsKeysLeftRight <- menuKeysStyle.Checked
+
+let MenuAutoMouseNavToggled (_: bool) =
+    menu.WantMousePositionReports <- menuAutoMouseNav.Checked
+
+let Copy () =
+    let textField = menu.LastFocused :?> TextField
+    if textField <> Unchecked.defaultof<_> && textField.SelectedLength <> 0
+    then textField.Copy ()
+
+let Cut () =
+    let textField = menu.LastFocused :?> TextField
+    if textField <> Unchecked.defaultof<_> && textField.SelectedLength <> 0
+    then textField.Cut ()
+
+let Paste () =
+    let textField = menu.LastFocused :?> TextField
+    if textField <> Unchecked.defaultof<_>
+    then textField.Paste ()
+
+let Help () =
+    MessageBox.Query (50, 7, ustr "Help", ustr "This is a small help\nBe kind.", ustr "Ok")
+    |> ignore
+
+let Load () =
+    MessageBox.Query (50, 7, ustr "Load", ustr "This is a small load\nBe kind.", ustr "Ok")
+    |> ignore
+
+let Save () =
+    MessageBox.Query (50, 7, ustr "Save ", ustr "This is a small save\nBe kind.", ustr "Ok")
+    |> ignore
+
+let ListSelectionDemo (multiple: bool) =
+    let okButton = new Button (ustr "Ok", true)
+    okButton.add_Clicked (Action (Application.RequestStop))
+    let cancelButton = new Button (ustr "Cancel")
+    cancelButton.add_Clicked (Action (Application.RequestStop))
+
+    let d = new Dialog (ustr "Selection Demo", 60, 20, okButton, cancelButton)
+    let animals = ResizeArray<_> ()
+    animals.AddRange([| "Alpaca"; "Llama"; "Lion"; "Shark"; "Goat" |])
+    let msg =
+        new Label (ustr "Use space bar or control-t to toggle selection",
+            X = Pos.At 1,
+            Y = Pos.At 1,
+            Width = Dim.Fill () - Dim.op_Implicit 1,
+            Height = Dim.op_Implicit 1)
+    let list =
+        new ListView (animals,
+            X = Pos.At 1,
+            Y = Pos.At 3,
+            Width = Dim.Fill () - Dim.op_Implicit 4,
+            Height = Dim.Fill () - Dim.op_Implicit 4,
             AllowsMarking = true,
-            AllowsMultipleSelection = multiple
-            )
-        d.Add (msg, list)
-        Application.Run (d)
-        let mutable result = ""
-        do
-            let mutable (i : int) = 0
-            while (i < animals.Count) do
-            if list.Source.IsMarked (i)
-            then result <- result + animals.[i] + " "
-            i <- i + 1
-            i
-            ()
-        MessageBox.Query (60, 10, ustr "Selected Animals", ustr (if result = "" then "No animals selected" else result), ustr "Ok") |> ignore
-
-    let OnKeyDownPressUpDemo() =
-        let closeButton = new Button(ustr "Close")
-        closeButton.add_Clicked(Action(Application.RequestStop))
-
-        let mutable container = new Dialog (ustr "KeyDown & KeyPress & KeyUp demo", 80, 20, closeButton, Width = Dim.Fill (), Height = Dim.Fill ())
-        
-        let mutable list = new List<string> ()
-        let mutable listView = new ListView (list,
-            X = Pos.At(0),
-            Y = Pos.At(0),
-            Width = Dim.Fill () - Dim.op_Implicit(1),
-            Height = Dim.Fill () - Dim.op_Implicit(2),
-            ColorScheme = Colors.TopLevel
-            )
-        container.Add (listView)
-        
-        let KeyDownPressUp(keyEvent : KeyEvent, updown : string) =
-            let ident : int = -5
-            match updown with
-            | "Down"
-            | "Up"
-            | "Press" -> 
-                list.Add (keyEvent.ToString ())    
-            listView.MoveDown ();
+            AllowsMultipleSelection = multiple)
+    d.Add (msg, list)
+    Application.Run d
+    let mutable result = ""
+    do
+        let mutable i = 0
+        while i < animals.Count do
+        if list.Source.IsMarked i
+        then result <- result + animals.[i] + " "
+        i <- i + 1
+    MessageBox.Query (60, 10, ustr "Selected Animals", ustr (if result = "" then "No animals selected" else result), ustr "Ok") |> ignore
+
+let OnKeyDownPressUpDemo () =
+    let closeButton = new Button (ustr "Close")
+    closeButton.add_Clicked (Action (Application.RequestStop))
+
+    let container = new Dialog (ustr "KeyDown & KeyPress & KeyUp demo", 80, 20, closeButton, Width = Dim.Fill (), Height = Dim.Fill ())
+    
+    let list = ResizeArray<_> ()
+    let listView = 
+        new ListView (list,
+            X = Pos.At 0,
+            Y = Pos.At 0,
+            Width = Dim.Fill () - Dim.op_Implicit 1,
+            Height = Dim.Fill () - Dim.op_Implicit 2,
+            ColorScheme = Colors.TopLevel)
+    container.Add (listView)
     
-        container.add_KeyDown(Action<View.KeyEventEventArgs> (fun (e : View.KeyEventEventArgs) -> KeyDownPressUp (e.KeyEvent, "Down") |> ignore))
-        container.add_KeyPress(Action<View.KeyEventEventArgs> (fun (e : View.KeyEventEventArgs) -> KeyDownPressUp (e.KeyEvent, "Press") |> ignore))
-        container.add_KeyUp(Action<View.KeyEventEventArgs> (fun (e : View.KeyEventEventArgs) -> KeyDownPressUp (e.KeyEvent, "Up") |> ignore))
-        Application.Run (container)
-
-    let Main() =
-        if Debugger.IsAttached
-        then CultureInfo.DefaultThreadCurrentUICulture <- CultureInfo.GetCultureInfo ("en-US")
-        Application.Init ()
-        let mutable top = Application.Top
-        let mutable (margin : int) = 3
-        let mutable win = new Window (ustr "Hello",
-            X = Pos.At(1),
-            Y = Pos.At(1),
-
-            Width = Dim.Fill () - Dim.op_Implicit(margin),
-            Height = Dim.Fill () - Dim.op_Implicit(margin)
-            )
-        let mutable (menuItems : MenuItemDetails[]) = [|new MenuItemDetails(ustr "F_ind", "", Unchecked.defaultof<_>);
-            new MenuItemDetails(ustr "_Replace", "", Unchecked.defaultof<_>);
-            new MenuItemDetails(ustr "_Item1", "", Unchecked.defaultof<_>);
-            new MenuItemDetails(ustr "_Also From Sub Menu", "", Unchecked.defaultof<_>)|]
-        menuItems.[0].Action <- fun () -> ShowMenuItem (menuItems.[0])
-        menuItems.[1].Action <- fun () -> ShowMenuItem (menuItems.[1])
-        menuItems.[2].Action <- fun () -> ShowMenuItem (menuItems.[2])
-        menuItems.[3].Action <- fun () -> ShowMenuItem (menuItems.[3])
-        menu <-
-            new MenuBar (
-                [|
-                    new MenuBarItem(ustr "_File",
-                        [|
-                            new MenuItem (ustr "Text _Editor Demo", ustring.Empty, (fun () -> Editor (top)))
-                            new MenuItem (ustr "_New", ustr "Creates new file", fun () -> NewFile())
-                            new MenuItem (ustr "_Open", ustring.Empty, fun () -> Open())
-                            new MenuItem (ustr "_Hex", ustring.Empty, (fun () -> ShowHex (top)))
-                            new MenuItem (ustr "_Close", ustring.Empty, (fun () -> Close()))
-                            new MenuItem (ustr "_Disabled", ustring.Empty, (fun () -> ()), (fun () -> false))
-                            Unchecked.defaultof<_>
-                            new MenuItem (ustr "_Quit", ustring.Empty, (fun () -> if Quit() then top.Running <- false))
-                        |]
-                    )
-                    new MenuBarItem (ustr "_Edit", 
-                        [|
-                            new MenuItem(ustr "_Copy", ustring.Empty, fun () -> Copy())
-                            new MenuItem(ustr "C_ut", ustring.Empty, fun () -> Cut())
-                            new MenuItem(ustr "_Paste", ustring.Empty, fun () -> Paste())
-                            new MenuBarItem(ustr "_Find and Replace",
-                                [|
-                                    menuItems.[0]
-                                    menuItems.[1]
-                                |]
-                            )
-                            menuItems.[3]
-                        |]
-                    )
-                    new MenuBarItem(ustr "_List Demos", 
-                        [|
-                            new MenuItem(ustr "Select _Multiple Items", ustring.Empty, (fun () -> ListSelectionDemo (true)))
-                            new MenuItem(ustr "Select _Single Item", ustring.Empty, (fun () -> ListSelectionDemo (false)))
-                        |]
-                    )   
-                    new MenuBarItem(ustr "A_ssorted",
-                        [|
-                            new MenuItem(ustr "_Show text alignments", ustring.Empty, (fun () -> ShowTextAlignments ())) 
-                            new MenuItem(ustr "_OnKeyDown/Press/Up", ustring.Empty, (fun () -> OnKeyDownPressUpDemo ()))
-                        |]
-                    )
-                    new MenuBarItem(ustr "_Test Menu and SubMenus",
-                        [|
-                            new MenuBarItem(ustr "SubMenu1Item_1",
-                                [|
-                                    new MenuBarItem(ustr "SubMenu2Item_1",
-                                        [|
-                                            new MenuBarItem(ustr "SubMenu3Item_1",
-                                                [|
-                                                    menuItems.[2]
-                                                |]
-                                            )
-                                        |]
-                                    )
-                                |]
-                            )
-                        |]
-                    )
-                    new MenuBarItem(ustr "_About...", ustr "Demonstrates top-level menu item", (fun() -> MessageBox.ErrorQuery (50, 7, ustr "Error", ustr "This is a demo app for gui.cs", ustr "Ok") |> ignore)
-                    )
-                |]
-            )
-        menuKeysStyle <- new CheckBox(3, 25, ustr "UseKeysUpDownAsKeysLeftRight", true)
-        menuKeysStyle.add_Toggled(Action<bool>(MenuKeysStyle_Toggled))
-        menuAutoMouseNav <- new CheckBox(40, 25, ustr "UseMenuAutoNavigation", true)
-        menuAutoMouseNav.add_Toggled(Action<bool>(MenuAutoMouseNav_Toggled))
-        ShowEntries (win)
-        let mutable (count : int) = 0
-        ml <- new Label(new Rect(3, 17, 47, 1), ustr "Mouse: ")
-        Application.RootMouseEvent <- Action<MouseEvent> (
-                fun (me : MouseEvent) ->
-                    ml.Text <- ustr (
-                         (((sprintf "Mouse: (%O,%O) - %O %O" me.X) me.Y) me.Flags) (
-                            count <- count + 1
-                            count))
-                            )
-        let mutable test = new Label(3, 18, ustr "Se iniciará el análisis")
-        win.Add (test)
-        win.Add (ml)
-        let mutable drag = new Label (ustr "Drag: ", X = Pos.At(70), Y = Pos.At(24))
-        let mutable dragText = new TextField (ustr "",
-            X = Pos.Right (drag),
-            Y = Pos.Top (drag),
-            Width = Dim.op_Implicit(40)
-            )
-        let mutable statusBar = new StatusBar ([|
-            new StatusItem(Key.F1, ustr "~F1~ Help", Action(Help));
-            new StatusItem(Key.F2, ustr "~F2~ Load", Action(Load));
-            new StatusItem(Key.F3, ustr "~F3~ Save", Action(Save));
-            new StatusItem(Key.ControlX, ustr "~^X~ Quit", fun () -> if (Quit ()) then top.Running <- false)
-            |]
-            )
-        win.Add (drag, dragText)
-        let mutable bottom = new Label(ustr "This should go on the bottom of the same top-level!")
-        win.Add (bottom)
-        let mutable bottom2 = new Label(ustr "This should go on the bottom of another top-level!")
-        top.Add (bottom2)
-        Application.Loaded <- Action<Application.ResizedEventArgs> (
-            fun (_) ->
-                bottom.X <- win.X
-                bottom.Y <- Pos.Bottom (win) - Pos.Top (win) - Pos.At(margin)
-                bottom2.X <- Pos.Left (win)
-                bottom2.Y <- Pos.Bottom (win)
-                )
-        top.Add (win)
-        top.Add (menu, statusBar)
-        Application.Run ()
-
-module Demo__run =
+    let keyDownPressUp (keyEvent: KeyEvent, updown: string) =
+        match updown with
+        | "Down"
+        | "Up"
+        | "Press" -> 
+            list.Add (keyEvent.ToString ())    
+        | _ -> failwithf "Unknown: %s" updown
+        listView.MoveDown ()
+
+    container.add_KeyDown(Action<View.KeyEventEventArgs> (fun (e: View.KeyEventEventArgs) -> keyDownPressUp (e.KeyEvent, "Down") |> ignore))
+    container.add_KeyPress(Action<View.KeyEventEventArgs> (fun (e: View.KeyEventEventArgs) -> keyDownPressUp (e.KeyEvent, "Press") |> ignore))
+    container.add_KeyUp(Action<View.KeyEventEventArgs> (fun (e: View.KeyEventEventArgs) -> keyDownPressUp (e.KeyEvent, "Up") |> ignore))
+    Application.Run (container)
+
+let Main () =
+    if Debugger.IsAttached then
+        CultureInfo.DefaultThreadCurrentUICulture <- CultureInfo.GetCultureInfo ("en-US")
+    Application.Init()
+    let top = Application.Top
+    let margin = 3
+    let win = 
+        new Window (ustr "Hello",
+            X = Pos.At 1,
+            Y = Pos.At 1,
+            Width = Dim.Fill () - Dim.op_Implicit margin,
+            Height = Dim.Fill () - Dim.op_Implicit margin)
+    let menuItems =
+        [|MenuItemDetails (ustr "F_ind", "", Unchecked.defaultof<_>);
+            MenuItemDetails (ustr "_Replace", "", Unchecked.defaultof<_>);
+            MenuItemDetails (ustr "_Item1", "", Unchecked.defaultof<_>);
+            MenuItemDetails (ustr "_Also From Sub Menu", "", Unchecked.defaultof<_>)|]
+    menuItems.[0].Action <- fun _ -> ShowMenuItem (menuItems.[0])
+    menuItems.[1].Action <- fun _ -> ShowMenuItem (menuItems.[1])
+    menuItems.[2].Action <- fun _ -> ShowMenuItem (menuItems.[2])
+    menuItems.[3].Action <- fun _ -> ShowMenuItem (menuItems.[3])
+    menu <-
+        new MenuBar (
+            [| MenuBarItem(ustr "_File",
+                    [| MenuItem (ustr "Text _Editor Demo", ustring.Empty, (fun () -> Editor top))
+                       MenuItem (ustr "_New", ustr "Creates new file", fun () -> NewFile())
+                       MenuItem (ustr "_Open", ustring.Empty, fun () -> Open())
+                       MenuItem (ustr "_Hex", ustring.Empty, (fun () -> ShowHex top))
+                       MenuItem (ustr "_Close", ustring.Empty, (fun () -> Close()))
+                       MenuItem (ustr "_Disabled", ustring.Empty, (fun () -> ()), (fun () -> false))
+                       Unchecked.defaultof<_>
+                       MenuItem (ustr "_Quit", ustring.Empty, (fun () -> if Quit() then top.Running <- false)) |])
+               MenuBarItem (ustr "_Edit", 
+                    [| MenuItem (ustr "_Copy", ustring.Empty, fun () -> Copy())
+                       MenuItem (ustr "C_ut", ustring.Empty, fun () -> Cut())
+                       MenuItem (ustr "_Paste", ustring.Empty, fun () -> Paste())
+                       MenuBarItem (ustr "_Find and Replace",
+                           [| menuItems.[0]
+                              menuItems.[1] |])
+                       menuItems.[3] |])
+               MenuBarItem (ustr "_List Demos", 
+                    [| MenuItem (ustr "Select _Multiple Items", ustring.Empty, (fun () -> ListSelectionDemo true))
+                       MenuItem (ustr "Select _Single Item", ustring.Empty, (fun () -> ListSelectionDemo false)) |])   
+               MenuBarItem(ustr "A_ssorted",
+                    [| MenuItem (ustr "_Show text alignments", ustring.Empty, (fun () -> ShowTextAlignments())) 
+                       MenuItem (ustr "_OnKeyDown/Press/Up", ustring.Empty, (fun () -> OnKeyDownPressUpDemo())) |])
+               MenuBarItem(ustr "_Test Menu and SubMenus",
+                    [| MenuBarItem (ustr "SubMenu1Item_1",
+                            [| MenuBarItem (ustr "SubMenu2Item_1",
+                                    [| MenuBarItem (ustr "SubMenu3Item_1",
+                                            [| menuItems.[2] |]) |]) |]) |])
+               MenuBarItem (ustr "_About...", ustr "Demonstrates top-level menu item", (fun () -> MessageBox.ErrorQuery (50, 7, ustr "Error", ustr "This is a demo app for gui.cs", ustr "Ok") |> ignore)) |])
+    menuKeysStyle <- new CheckBox (3, 25, ustr "UseKeysUpDownAsKeysLeftRight", true)
+    menuKeysStyle.add_Toggled (Action<bool> (MenuKeysStyleToggled))
+    menuAutoMouseNav <- new CheckBox (40, 25, ustr "UseMenuAutoNavigation", true)
+    menuAutoMouseNav.add_Toggled (Action<bool> (MenuAutoMouseNavToggled))
+    ShowEntries win
+    let mutable count = 0
+    ml <- new Label (Rect (3, 17, 47, 1), ustr "Mouse: ")
+    Application.RootMouseEvent <- Action<MouseEvent> (
+            fun (me: MouseEvent) ->
+                ml.Text <- ustr (
+                     (((sprintf "Mouse: (%O,%O) - %O %O" me.X) me.Y) me.Flags) (count <- count + 1; count)))
+    let test = new Label (3, 18, ustr "Se iniciará el análisis")
+    win.Add test
+    win.Add ml
+    let drag = new Label (ustr "Drag: ", X = Pos.At 70, Y = Pos.At 24)
+    let dragText = 
+        new TextField (ustr "",
+            X = Pos.Right drag,
+            Y = Pos.Top drag,
+            Width = Dim.op_Implicit 40)
+    let statusBar = new StatusBar ([|
+        StatusItem(Key.F1, ustr "~F1~ Help", Action Help)
+        StatusItem(Key.F2, ustr "~F2~ Load", Action Load)
+        StatusItem(Key.F3, ustr "~F3~ Save", Action Save)
+        StatusItem(Key.ControlX, ustr "~^X~ Quit", fun () -> if (Quit()) then top.Running <- false) |])
+    win.Add (drag, dragText)
+    let bottom = new Label (ustr "This should go on the bottom of the same top-level!")
+    win.Add bottom
+    let bottom2 = new Label (ustr "This should go on the bottom of another top-level!")
+    top.Add bottom2
+    Application.Loaded <- Action<Application.ResizedEventArgs> (
+        fun _ ->
+            bottom.X <- win.X
+            bottom.Y <- Pos.Bottom win - Pos.Top win - Pos.At margin
+            bottom2.X <- Pos.Left win
+            bottom2.Y <- Pos.Bottom win)
+    top.Add win
+    top.Add (menu, statusBar)
+    Application.Run ()
+
+module Demo =
     [<EntryPoint>]
-    let main argv =
+    let main _ =
         Main ()
         0