public class TreeSet<T> extends AbstractSet<T> implements Collection<T> {
private PersistentSet<Cell<T>> set;
public TreeSet(final Comparator<T> comparator) {
set = new PersistentSet(new Comparator<Cell<T>>() {
public int compare(Cell<T> a, Cell<T> b) {
return comparator.compare(a.value, b.value);
}
});
}