code: public static Predicate<Tuple2<Context<?>, Boolean>> onlyRules(final Rule... rules) {
          return new Predicate<Tuple2<Context<?>, Boolean>>() {
              public boolean apply(Tuple2<Context<?>, Boolean> tuple) {
                  for (Rule rule : rules) if (tuple.a.getMatcher() == rule) return true;
                  return false;
              }
          };
      }
docs: A predicate usable as a filter (element) of a {@link org.parboiled.parserunners.TracingParseRunner}.
  Enables printing of rule tracing log messages for all given rules (without their sub rules).
  
  @param rules the rules to generate tracing message for
  @return a predicate