-/** a tree (or node in a tree); see jargon.txt for details */
-public class Tree<T>
- extends PrintableTree<Tree<T>>
- implements Iterable<Tree<T>>,
- GraphViz.ToGraphViz {
-
- final T head;
- Tree<T>[] children;
- Object[] labels;
- final Input.Location location;
-
- public T head() { return head; }
- public int numChildren() { return children.length; }
- public Iterable<Tree<T>> children() { return new ArrayIterator(children); }
- public Iterator<Tree<T>> iterator() { return new ArrayIterator(children); }
- public Tree<T> child(int i) { return children[i]; }
- public Object label(int i) { return labels[i]; }
-
- public Input.Location getLocation() { return location; }
-
- public Tree(Input.Location loc, T head) { this(loc, head, null); }
- public Tree(Input.Location loc, T head, Tree<T>[] children) { this(loc, head, children, null); }
- public Tree(Input.Location loc, T head, Tree<T>[] children, Object[] labels) {
+/** <font color=blue>a tree (or node in a tree); see jargon.txt for details</font> */
+public class Tree<NodeType>
+ extends PrintableTree<Tree<NodeType>>
+ implements Iterable<Tree<NodeType>> {
+
+ private final Input.Region location;
+ private final NodeType head;
+ private final Tree<NodeType>[] children;
+ private final boolean lift;
+
+ /** the element at the head of the tree */
+ public NodeType head() { return head; }
+
+ private Tree<NodeType> lifted() { return children[children.length-1]; }
+
+ /** the number of children the tree has */
+ public int size() {
+ return lift
+ ? (children.length-1)+lifted().size()
+ : children.length;
+ }
+
+ /** the tree's children */
+ public Iterable<Tree<NodeType>> children() { return this; }
+
+ /** the tree's children */
+ public Iterator<Tree<NodeType>> iterator() {
+ return lift
+ ? new ConcatenateIterator(new ArrayIterator(children, 0, children.length-1),
+ children[children.length-1].iterator())
+ : new ArrayIterator(children);
+ }
+
+ /** get the <tt>i</t>th child */
+ public Tree<NodeType> child(int i) {
+ return lift && i >= children.length-1
+ ? children[children.length-1].child(i-(children.length-1))
+ : children[i];
+ }
+
+ /** get the input region that this tree was parsed from */
+ public Input.Region getRegion() { return location; }
+
+ public Tree(Input.Region loc, NodeType head) { this(loc, head, null); }
+ public Tree(Input.Region loc, NodeType head, Tree<NodeType>[] children) { this(loc, head, children, false); }
+
+ /** package-private constructor, allows setting the "lift" bit */
+ Tree(Input.Region loc, NodeType head, Tree<NodeType>[] children, boolean lift) {