static O[] onlyNonNullParams(O... params) {
  new L out;
  for (int i = 0; i+1 < l(params); i += 2)
    if (params[i] != null && params[i+1] != null) {
      out.add(params[i]);
      out.add(params[i+1]);
    }
  ret toObjectArray(out);
}