static L<S> splitAtEmptyLines(S text) {
  L<S> lines = toLines(text);
  int n = l(lines), i = 0;
  new L<S> parts;
  while true {
    while (i < n && emptyAfterTrim(lines.get(i))) ++i;
    if (i >= n) break;
    int j = i;
    while (j < n && !emptyAfterTrim(lines.get(j))) ++j;
    parts.add(fromLines(subList(lines, i, j)));
    i = j;
  }
  ret parts;
}