s = format (s, "Used slots: %wu\n", used);
s = format (s, "Use count total: %wu\n", use_count_total);
s = format (s, "Free slots: %wu\n", free);
s = format (s, "Used slots: %wu\n", used);
s = format (s, "Use count total: %wu\n", use_count_total);
s = format (s, "Free slots: %wu\n", free);