docs: static Matcher combineAdjacentStart(Matcher matcher) {
      if (matcher instanceof SeqMatcher) {
        List<Matcher> matchers = matcher.<SeqMatcher>as().matchers();
        if (!matchers.isEmpty() && matchers.get(0) instanceof StartMatcher) {
          List<Matcher> ms = new ArrayList<>();
          ms.add(StartMatcher.INSTANCE);
          int pos = 0;
          for (Matcher m : matchers) {
            if (m instanceof StartMatcher) {
              ++pos;
            } else {
              break;
            }
          }
          ms.addAll(matchers.subList(pos, matchers.size()));
          return SeqMatcher.create(ms);
        }
      }
      return matcher;
    }