static L mapAndRecordToMap(Map recordMap, Iterable l, O f) {
  ret mapAndRecordToMap(recordMap, f, l);
}

static L mapAndRecordToMap(Map recordMap, O f, Iterable l) {
  L x = emptyList(l);
  if (l != null) for (O o : l) {
    O b = callF(f, o);
    if (recordMap != null) recordMap.put(o, b);
    x.add(b);
  }
  ret x;
}