static LS tok_splitAtPlusAtBeginningOfLine(S s) {
  new L<Int> indices;
  LS tok = javaTokWithAllBrackets_cached(s);
  for (int i = 1; i < l(tok); i += 2)
    if (eqGet(tok, i, "+") && containsNewLine(get(tok, i-1)))
      indices.add(i);
  ret splitAtTokenIndices(tok, indices);
}