generic
   type Value_Type is private;
package Predicate5 is
   type MT (Has : Boolean := False) is record
      case Has is
         when False =>
            null;
         when True =>
            MX : Value_Type;
      end case;
   end record;
   function Foo (M : MT) return Boolean is (not M.Has);
   subtype LT is MT with Dynamic_Predicate => not LT.Has;
   function Bar (M : MT) return Boolean is (Foo (M));

   procedure Foo;
end;