+
+ public static interface TreeFunctor<T,R> extends Functor<Iterable<Tree<T>>, R> {
+ }
+
+ public static class ArrayBuildingTreeFunctor<T> implements TreeFunctor<T,T[]>, ToJava {
+
+ public void toJava(StringBuffer sb) { sb.append("new Tree.ArrayBuildingTreeFunctor()"); }
+ public String toString() { return ""; }
+
+ public T[] invoke(Iterable<Tree<T>> t) {
+ ArrayList ret = new ArrayList();
+ for(Tree tc : t) {
+ if (tc.head() != null && tc.head() instanceof Functor)
+ ret.add(((Functor<Iterable<Tree>,Object>)tc.head()).invoke(tc.children()));
+ else if (tc.numChildren() == 0)
+ ret.add(tc.head());
+ else {
+ System.err.println("FIXME: don't know what to do about " + tc);
+ ret.add(null);
+ }
+ }
+ return (T[])ret.toArray(new Object[0]);
+ }
+ }