static L<S> splitAt_withEmptyLast(S s, S splitter) {
  new L<S> parts;
  if (nempty(s)) {
    int i = 0;
    while (i < l(s)) {
      int j = indexOf(s, splitter, i);
      if (j < 0) break;
      parts.add(substring(s, i, j));
      i = j+l(splitter);
    }
    parts.add(substring(s, i));
  }
  ret parts;
}