X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FTree.java;h=d2bfc4bbc46a6bf379bd79633fff7746bb1bc834;hp=e9c9a45080bd2c8bacb13db05f160f53c91136bd;hb=d86c2344f6f5b958d56e2aa55e84af2dc76ab487;hpb=5ae7d4fd7c53dab6df9aae2e42579efabf66f49e

diff --git a/src/edu/berkeley/sbp/Tree.java b/src/edu/berkeley/sbp/Tree.java
index e9c9a45..d2bfc4b 100644
--- a/src/edu/berkeley/sbp/Tree.java
+++ b/src/edu/berkeley/sbp/Tree.java
@@ -12,47 +12,56 @@ public class Tree<T>
     implements Iterable<Tree<T>>,
                GraphViz.ToGraphViz {
 
+    private final Input.Region location;
     private final T            head;
     private final Tree<T>[]    children;
-    private final Input.Region location;
     private final boolean      lift;
 
+    /** the element at the head of the tree */
     public T                 head()        { return head; }
 
     private Tree<T> lifted() { return children[children.length-1]; }
 
+    /** the number of children the tree has */
     public int               numChildren() {
-        if (lift && children.length > 0)
-            return (children.length-1)+lifted().numChildren();
-        return children.length;
+        return lift
+            ? (children.length-1)+lifted().numChildren()
+            : children.length;
     }
+
+    /** the tree's children */
     public Iterable<Tree<T>> children()    { return this; }
+
+    /** the tree's children */
     public Iterator<Tree<T>> iterator()    {
-        if (lift)
-            return new ConcatenateIterator(new ArrayIterator(children, 0, children.length-1),
-                                           children[children.length-1].iterator());
-        return new ArrayIterator(children);
+        return lift
+            ? new ConcatenateIterator(new ArrayIterator(children, 0, children.length-1),
+                                      children[children.length-1].iterator())
+            : new ArrayIterator(children);
     }
-    public Tree<T>           child(int i)  {
-        if (lift && i >= children.length-1)
-            return children[children.length-1].child(i-(children.length-1));
-        return children[i];
+
+    /** get the <tt>i</t>th child */
+    public Tree<T> 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, T head)                   { this(loc, head, null); }
+    public Tree(Input.Region loc, T head)                     { this(loc, head, null); }
     public Tree(Input.Region loc, T head, Tree<T>[] children) { this(loc, head, children, false); }
-    public Tree(Input.Region loc, T head, Tree<T>[] children, boolean lift) {
+    Tree(Input.Region loc, T head, Tree<T>[] children, boolean lift) {
         this.location = loc;
         this.head = head;
-        this.lift = lift;
-
-        Tree<T>[] children2 = children==null ? new Tree[0] : new Tree[children.length];
-        if (children != null) System.arraycopy(children, 0, children2, 0, children.length);
-        this.children = children2;
+        this.lift = lift && children != null && children.length > 0;
+        this.children = ArrayUtil.clone(children, Tree.class);
     }
 
+
+    // PrintableTree /////////////////////////////////////////////////////////////////////////////
+
     protected String headToString() { return head()==null?null:head().toString(); }
     protected String headToJava()   {
       // FIXME
@@ -68,6 +77,9 @@ public class Tree<T>
     protected String right()  { return "}"; }
     protected boolean ignoreSingleton() { return false; }
 
+
+    // ToGraphViz /////////////////////////////////////////////////////////////////////////////
+
     public GraphViz.Node toGraphViz(GraphViz gv) {
         if (gv.hasNode(this)) return gv.createNode(this);
         GraphViz.Node n = gv.createNode(this);
@@ -79,86 +91,9 @@ public class Tree<T>
     public boolean isTransparent() { return false; }
     public boolean isHidden() { return false; }
 
-    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]);
-        }
-    }
-
-    public static class RawBindingFunctor<T> implements TreeFunctor<T,Object>, ToJava {
-        private Binding _binding;
-        private String _toString;
-        public RawBindingFunctor(String toString, Binding binding) {
-            this._binding = binding;
-            this._toString = toString;
-        }
-        public String toString() {
-            return _toString;
-        }
-        public void toJava(StringBuffer sb) {
-            sb.append("new Tree.RawBindingFunctor(");
-            sb.append("\"");
-            sb.append(StringUtil.toJavaString(_toString));
-            sb.append("\", ");
-            _binding.toJava(sb);
-            sb.append(")");
-        }
-        public Object invoke(Iterable<Tree<T>> t) {
-            return _binding.invoke(new Object[] { t });           
-        }
-    }
-
-    public static class BindingFunctor<T> implements TreeFunctor<T,Object>, ToJava {
-        private Binding _binding;
-        private String _toString;
-        public String toString() {
-            return _toString;
-        }
-        public BindingFunctor(String toString, Binding binding) {
-            this._binding = binding;
-            this._toString = toString;
-        }
-        public void toJava(StringBuffer sb) {
-            sb.append("new Tree.BindingFunctor(");
-            sb.append("\"");
-            sb.append(StringUtil.toJavaString(_toString));
-            sb.append("\", ");
-            _binding.toJava(sb);
-            sb.append(")");
-        }
-        public Object invoke(Iterable<Tree<T>> t) {
-            ArrayList ret = new ArrayList();
-            for(Tree tc : t) {
-                if (tc.head() != null && tc.head() instanceof Functor)
-                    ret.add(((Tree.TreeFunctor<Object,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);
-                }
-            }
-            Object[] o = (Object[])ret.toArray(new Object[0]);
-            return _binding.invoke(o);
-        }
-    }
+    // TreeFunctor /////////////////////////////////////////////////////////////////////////////
 
+    public static interface TreeFunctor<T,R> extends Functor<Iterable<Tree<T>>, R> { }
+    
 }