public Parser identifier_format1() {
        if (identifier_format1Parser == null) {
           FutureParser future = scoped("identifier_format1");
           identifier_format1Parser = future;
           future.setParser(
               sequence(
                   function(),
                   optional(
                       referenceModifier()
                   )
               )
           );
        }

        return identifier_format1Parser;
    }