sclass SimpleFactStore implements IFactStore {
  L<Fact> facts = synchroList();
  
  sclass Fact extends HasGlobalID {
    long created = now();
    S text;
    
    *() {}
    *(S *text) {}
    
    toString { ret text; }
  }
  
  public void store(S fact) {
    if (!hasWhereIC(facts, fact))
      facts.add(new Fact(fact));
  }
  
  public void deleteAll(IPred<S> filter) {
    for (Fact f : cloneList(facts))
      if (filter.get(f.text))
        facts.remove(f);
  }
  
  LS facts() { ret map(facts, f -> f.text); }
}