static <A, B, C> LinkedHashMap<A, B> lambdaMapLike mapSortedByFunctionOnKey(IF1<A, C> f, Map<A, B> map) {
  L<A> l = new ArrayList(map.keySet());
  sortInPlaceByCalculatedField(l, f);
  new LinkedHashMap<A, B> map2;
  for (A a : l)
    map2.put(a, map.get(a));
  ret map2;
}