public Parser procedureName() {
        if (procedureNameParser == null) {
           FutureParser future = scoped("procedureName");
           procedureNameParser = future;
           future.setParser(
               sequence(
                   choice(
                       cobolWord(),
                       integer()
                   ),
                   optional(
                       sequence(
                           choice(
                               token("IN"),
                               token("OF")
                           ),
                           cobolWord()
                       )
                   )
               )
           );
        }

        return procedureNameParser;
    }