scope ai_wordCategoriesWithElements.

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

static Map<S, Set<S>> ai_wordCategoriesWithElements() {
  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() {
  final Map<S, Set<S>> wordCategories = ciMap();
  for (S cat : mL("All " + ai_language() + " word categories"))
    putIfValueNempty(wordCategories, cat, combinedMechSetsCI(ai_mechListNamesForAngleBracketCategory(cat)));
  ret wordCategories;
}

end scope

Began life as a copy of #1017343