X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FForest.java;h=d7716dd7594c7dda1c6df063c73c5931d9fb666a;hb=c7423816fa31bbf7177a84be372d153f8a3327b5;hp=df7a3ea2d0a9a2a1eed3c1de1cedef4d2996b25e;hpb=02d1ec40a590520818d5fd7c3c1f68c161ce5567;p=sbp.git

diff --git a/src/edu/berkeley/sbp/Forest.java b/src/edu/berkeley/sbp/Forest.java
index df7a3ea..d7716dd 100644
--- a/src/edu/berkeley/sbp/Forest.java
+++ b/src/edu/berkeley/sbp/Forest.java
@@ -7,19 +7,7 @@ import java.util.*;
 import java.lang.reflect.*;
 
 /** an efficient representation of a collection of trees (Tomita's shared packed parse forest) */
-public abstract class Forest<T> /*extends PrintableTree<Forest.Body<T>>*/ implements Visitable<Forest.Body<T>> {
-
-    public abstract <B,C> void invoke(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c);
-    private static class TreeMaker<T> extends HashSet<Tree<T>> implements Invokable<Forest.Body<T>,Boolean,Integer> {
-        public ArrayList<Tree<T>> toks = new ArrayList<Tree<T>>();
-        public void invoke(Forest.Body<T> bod, Boolean toss, Integer i) {
-            if (i==null) {
-                addAll(bod.expand(toss, 0, new TreeMaker<T>()));
-            } else {
-                bod.expand(toss, i, this);
-            }
-        }
-    }
+public abstract class Forest<T> /*extends PrintableTree<Forest.MyBody<T>>*/ implements Visitable<Forest.Body<T>> {
 
     /** assume that this forest contains exactly one tree and return it; otherwise throw an exception */
     public final Tree<T> expand1() throws Ambiguous, ParseFailed {
@@ -30,10 +18,15 @@ public abstract class Forest<T> /*extends PrintableTree<Forest.Body<T>>*/ implem
 
     /** expand this forest into a set of trees */
     public HashSet<Tree<T>> expand(boolean toss) {
-        TreeMaker<T> ret = new TreeMaker<T>();
-        invoke(ret, new Boolean(toss), null);
-        if (toss && ret.size() > 1) throw new Ambiguous(this);
-        return ret;
+        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;
     }
 
     static        <T> Forest<T> singleton(Input.Location loc)                       { return create(loc, null, new Forest[] { }, false, true); }
@@ -46,15 +39,14 @@ public abstract class Forest<T> /*extends PrintableTree<Forest.Body<T>>*/ implem
     // Body //////////////////////////////////////////////////////////////////////////////
 
     protected static interface Body<T> {
-        TreeMaker<T> expand(boolean toss, int i, TreeMaker<T> h);
+        TreeMaker<T> expand(int i, TreeMaker<T> h);
     }
 
     protected static class MyBody<T> extends Forest<T> implements Body<T> /* extends PrintableTree<Forest<T>> implements */ {
 
-        public <B,C> void invoke(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c) {
+        public <B,C> void visit(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c) {
             ivbc.invoke(this, b, c);
         }
-        public Iterator<Body<T>> iterator() { return new SingletonIterator<Body<T>>(this); }
 
         private final Input.Location    location;
         private final T                 tag;
@@ -72,27 +64,31 @@ public abstract class Forest<T> /*extends PrintableTree<Forest.Body<T>>*/ implem
             this.singleton = singleton;
         }
 
-        public TreeMaker<T> expand(boolean toss, int i, TreeMaker<T> h) {
+        public TreeMaker<T> expand(final int i, final TreeMaker<T> h) {
             if (singleton) {
-                tokens[0].invoke(h, toss, i);
+                tokens[0].visit(h, null, i);
+                return h;
+            }
+            if (i==0) h.start(tag, location);
 
-            } else if (i==tokens.length) {
-                h.add(new Tree<T>(null, tag, h.toks.toArray(tree_hint)));
+            if (i==tokens.length) {
+                h.finish(tag, location);
 
             } else if (unwrap && i==tokens.length-1) {
                 if (tokens[i] != null)
-                    tokens[i].invoke(h, toss, 0);
+                    tokens[i].visit(h, null, 0);
 
             } else {
-                boolean hit = false;
-                for(Tree<T> r : tokens[i].expand(toss)) {
-                    hit = true;
-                    int old = h.toks.size();
-                    h.toks.add(r);
-                    expand(toss, i+1, h);
-                    while(h.toks.size() > old) h.toks.remove(h.toks.size()-1);
-                }
-                //if (!hit) throw new Error();
+                tokens[i].visit(new TreeMaker<T>(h.toss) {
+                    public void start(T head, Input.Location loc) { }
+                    public void child(Tree<T> t) { toks.add(t); }
+                    public void finish(T head, Input.Location loc) {
+                        int old = h.toks.size();
+                        h.child(new Tree<T>(loc, head, toks.toArray(tree_hint)));
+                        expand(i+1, h);
+                        while(h.toks.size() > old) h.toks.remove(h.toks.size()-1);
+                    }
+                }, null, null);
             }
             return h;
         }
@@ -116,13 +112,34 @@ public abstract class Forest<T> /*extends PrintableTree<Forest.Body<T>>*/ implem
         private FastSet<Forest<T>> hp = new FastSet<Forest<T>>();
         public Ref() { }
         public void merge(Forest p) { if (p!=this) hp.add(p, true); }
-        public <B,C> void invoke(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c) {
+        public <B,C> void visit(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c) {
             if (hp==null) return;
-            for(Forest<T> f : hp) f.invoke(ivbc, b, c);
+            for(Forest<T> f : hp)
+                f.visit(ivbc, b, c);
         }
         public Forest resolve() { return this; }
     }
 
+    public abstract <B,C> void visit(Invokable<Forest.Body<T>,B,C> ivbc, B b, C c);
+    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;
+        protected T head;
+        public TreeMaker(boolean toss) { this.toss = toss; }
+        public abstract void start(T head, Input.Location loc);
+        public abstract void finish(T head, Input.Location loc);
+        public abstract void child(Tree<T> t);
+        public void invoke(Forest.Body<T> bod, Boolean o, Integer i) {
+            if (i==null) {
+                ArrayList<Tree<T>> toks = this.toks;
+                this.toks = new ArrayList<Tree<T>>();
+                bod.expand(0, this);
+                this.toks = toks;
+            } else {
+                bod.expand(i, this);
+            }
+        }
+    }
 
     // Statics //////////////////////////////////////////////////////////////////////////////