// for ai_language()
// Uses mech list "All $language word categories" and sublists
scope ai_wordToCategories.

static TimedCache<Map<S, Map<S, Set<S>>>> #cache = new TimedCache(f ciMap, 10.0); // language -> word -> categories

static Map<S, Set<S>> ai_wordToCategories() {
  Map<S, Map<S, Set<S>>> languages = cache!;
  Map<S, Set<S>> map = languages.get(ai_language());
  if (map == null)
    languages.put(ai_language(), map = make());
  ret map;
}

static Map<S, Set<S>> #make() {
  Map<S, Set<S>> catMap = ai_wordCategoriesWithElements();
  
  final Map<S, Set<S>> map = ciMap();
  for (S cat : keys(catMap))
    for (S word : catMap.get(cat)) {
      Set<S> set = map.get(word);
      if (set == null) map.put(word, set = new LinkedHashSet);
      set.add(cat);
    }
  ret map;
}

static Set<S> ai_wordToCategories(S word) {
  ret ai_wordToCategories().get(word);
}

end scope