static int cmp(Number a, Number b) {
  ret a == null ? b == null ? 0 : -1 : cmp(a.doubleValue(), b.doubleValue());
}

static int cmp(double a, double b) {
  ret a < b ? -1 : a == b ? 0 : 1;
}

static int cmp(int a, int b) {
  ret a < b ? -1 : a == b ? 0 : 1;
}

static int cmp(long a, long b) {
  ret a < b ? -1 : a == b ? 0 : 1;
}

static int cmp(O a, O b) {
  if (a == null) ret b == null ? 0 : -1;
  if (b == null) ret 1;
  ret ((Comparable) a).compareTo(b);
}

Began life as a copy of #1001540