> Would it be possible that Sequence<T> extends Iterable<T>? So that you can > use any Sequence instance in a for-each loop, not just some specialized > subclasses such as TablePane.ColumnSequence.
List<T> is meant to serve this purpose. List<T> extends Sequence<T> and Collection<T>, which extends Iterable<T>. Similarly, Map<K, V> extends Dictionary<K, V> and Collection<K>, and Set<E> extends Group<E> and Collection<E>. This approach allows us to combine collection behaviors without collisions on the Iterable type (for example, org.apache.pivot.xml.Element implements List<Node> and Dictionary<String, String>, which wouldn't compile if Dictionary also implemented Iterable). We use Sequence rather than List in our inner classes primarily because we want the associated mutator events to be fired from the outer class, rather than the sequence itself, as we would need to do if the sequences implemented List (they would need to fire ListListener events).
