static Map<S, Int> ai_indexToNr_map = litcimap(
  "first", 1,
  "second", 2,
  "third", 3,
  "fourth", 4,
  "fifth", 5,
  "sixth", 6,
  "seventh", 7,
  "eighth", 8,
  "ninth", 9,
  "tenth", 10);
  
static Int ai_indexToNr(S s) {
  ret mapGet(ai_indexToNr_map, s);
}