checkpoint

darcs-hash:20060122103030-5007d-0eb08ef6167373dad28a87a904c3af79c212b681.gz

diff --git a/src/edu/berkeley/sbp/Forest.java b/src/edu/berkeley/sbp/Forest.java
index 420d655..475b300 100644 (file)
--- a/src/edu/berkeley/sbp/Forest.java
+++ b/src/edu/berkeley/sbp/Forest.java
@@ -18,15 +18,17 @@ public abstract class Forest<T> /*extends PrintableTree<Forest.MyBody<T>>*/ impl
 
     /** expand this forest into a set of trees */
     public HashSet<Tree<T>> expand(boolean toss) {
-        final HashSet<Tree<T>> hs = new HashSet<Tree<T>>();
-        TreeMaker<T> ret = new TreeMaker<T>(toss) {
-            public void start(T head, Input.Location loc) { }
-            public void finish(T head, Input.Location loc) { hs.add(new Tree<T>(loc, head, toks.toArray(tree_hint))); }
-            public void child(Tree<T> t) { toks.add(t); }
-        };
-        visit(ret, null, null);
-        if (toss && hs.size() > 1) throw new Ambiguous(this);
-        return hs;
+        final HashSetTreeConsumer<T> ret = new HashSetTreeConsumer<T>();
+        visit(new TreeMaker2<T>(toss, ret), null, null);
+        if (toss && ret.size() > 1) throw new Ambiguous(this);
+        return ret;
+    }
+
+    public static interface TreeConsumer<T> {
+        public void addTree(Tree<T> t);
+    }
+    public static class HashSetTreeConsumer<T> extends HashSet<Tree<T>> implements TreeConsumer<T> {
+        public void addTree(Tree<T> t) { super.add(t); }
     }
 
     static        <T> Forest<T> singleton(Input.Location loc)                       { return create(loc, null, new Forest[] { }, false, true); }
@@ -120,6 +122,13 @@ public abstract class Forest<T> /*extends PrintableTree<Forest.MyBody<T>>*/ impl
     }
 
     public abstract <B,C> void visit(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c);
+    private static class TreeMaker2<T> extends TreeMaker<T> {
+        private TreeConsumer<T> tc;
+        public TreeMaker2(boolean toss, TreeConsumer<T> tc) { super(toss); this.tc = tc; }
+        public void finish(T head, Input.Location loc) { tc.addTree(new Tree<T>(loc, head, toks.toArray(tree_hint)));; }
+        public void start(T head, Input.Location loc) { }
+        public void child(Tree<T> t) { toks.add(t); }
+    }
     private static abstract class TreeMaker<T> implements Invokable<Forest.Body<T>,Boolean,Integer> {
         public ArrayList<Tree<T>> toks = new ArrayList<Tree<T>>();
         private boolean toss;