scope ai_mechListNamesForAngleBracketCategory.

// TODO: clean on language change
static TimedCache<Map<S, Set<S>>> #cache = TimedCache(5.0);

static Set<S> ai_mechListNamesForAngleBracketCategory(S s) {
  if (!isAngleBracketed(s)) null;
  Map<S, Set<S>> map = cache.get(f newHashMap);
  s = dropTrailingNumberFromAngleBracketCategory(s);
  if (map.containsKey(s)) ret map.get(s);
  // Derive from the category name - use LinkedHashSet to keep first
  Set<S> set = litorderedset(mechLanguagePrefix() + firstToUpper(plural_mech(replace(deAngleBracket(s), "_", " "))));
  set.addAll(mechMultiMapCI(mechLanguagePrefix() + "Word category => List").get(s));
  map.put(s, set);
  ret set;
}

end scope