static Map mapToValues_treeMap(Iterable l, O f) {
  ret mapToValues_treeMap(f, l);
}

static Map mapLike mapToValues_treeMap(O f, Iterable l) {
  new TreeMap map;
  if (l != null) for (O o : l)
    map.put(o, callF(f, o));
  ret map;
}

static <A, B> Map<A, B> mapToValues_treeMap(Iterable<A> l, IF1<A, B> f) {
  ret mapToValues_treeMap(f, l);
}

Began life as a copy of #1024406