sclass ConceptL extends Concept implements Iterable<Concept> {
  new RefL<Concept> l;
  
  *() {}
  *(L l) { main addAll(this.l, l); }
  
  void addAll(L l) {
    this.l.addAll(l);
  }
  
  public Iterator<Concept> iterator() {
    ret l.iterator();
  }
  
  public L<Concept> getList() {
    ret l;
  }
}