code: public static CharSequence join(CharSequence delimiter, Iterable<? extends CharSequence> list) {
      Iterator<? extends CharSequence> it = list.iterator();
      if (it.hasNext()) {
        StringBuilder sb = new StringBuilder(it.next());
        while (it.hasNext()) {
          sb.append(delimiter);
          sb.append(it.next());
        }
        return sb.toString();
      }
      return "";
    }
docs: TODO(schmitt): Move to a better location.