static int intMax(Collection c, S field) {
  int max = Int.MIN_VALUE;
  for (O o : c)
    max = Math.max(max, toInt(getOpt(o, field)));
  ret max;
}

static int intMax(Iterable<Int> l) {
  int max = Int.MIN_VALUE;
  fOr (int i : l)
    max = Math.max(max, i);
  ret max;
}

static int intMax(int... l) {
  int max = Int.MIN_VALUE;
  if (l != null) for (int i : l)
    max = Math.max(max, i);
  ret max;
}

Began life as a copy of #1006064