result.append(super.toString());
  public String toString()  {    StringBuffer result = new StringBuffer();    if (this == PureFactory.empty) {      return "[]";    }    result.append("[");    ATermList list = this;    while (!list.isEmpty()) {      result.append(list.getFirst().toString());      list = list.getNext();      if (!list.isEmpty()) {	result.append(",");      }    }        result.append("]");    return result.toString();  }