generic
      type User_Data_Type (<>) is private;
      with procedure Destroy (Data : in out User_Data_Type) is null;
   package Request_Rich_Text_User_Data is

type User_Data_Type (<>) is private;

type Gtk_Clipboard_Rich_Text_Received_Func is access procedure
        (Clipboard : not null access Gtk.Clipboard.Gtk_Clipboard_Record'Class;
         Format    : Gdk.Types.Gdk_Atom;
         Text      : in out Guint8;
         Length    : Gsize;
         Data      : User_Data_Type);

procedure Destroy 
(
Data
: in out User_Data_Type) is null;

procedure Request_Rich_Text 
(
Clipboard
: not null access Gtk.Clipboard.Gtk_Clipboard_Record'Class;
Buffer
: not null access Glib.Object.GObject_Record'Class;
Callback
: Gtk_Clipboard_Rich_Text_Received_Func;
User_Data
: User_Data_Type);