| Box.Object (_,obj)::tl -> aux_h (current_s ^ (object_to_string obj)) tl
| (Box.Action _)::tl -> assert false
| (Box.Ink _)::tl -> aux_h (current_s ^ "----------") tl
| Box.Object (_,obj)::tl -> aux_h (current_s ^ (object_to_string obj)) tl
| (Box.Action _)::tl -> assert false
| (Box.Ink _)::tl -> aux_h (current_s ^ "----------") tl