Natools

   type Interpreter is new Command with private;

   procedure Add_Command
     (Self : in out Interpreter;
      Name : in Atom;
      Cmd : in Command'Class);

   function Has_Command (Self : Interpreter; Name : Atom) return Boolean;

   function Is_Empty (Self : Interpreter) return Boolean;

   procedure Set_Fallback
     (Self : in out Interpreter;
      Name : in Atom);

   procedure Reset_Fallback (Self : in out Interpreter);