X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FForest.java;h=34759e366148392ceb9fa07e9e5ed322c1a107a9;hb=4cc825538bcfaacea47ba7c89a1e47321a95baab;hp=ef420a8379e4991bd0b488278d8e67748a54732c;hpb=dac355890ce94f5ec7204142aec9a33ad8f81214;p=sbp.git

diff --git a/src/edu/berkeley/sbp/Forest.java b/src/edu/berkeley/sbp/Forest.java
index ef420a8..34759e3 100644
--- a/src/edu/berkeley/sbp/Forest.java
+++ b/src/edu/berkeley/sbp/Forest.java
@@ -7,241 +7,130 @@ 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> {
+public abstract class Forest<T> /*extends PrintableTree<Forest.Body<T>>*/ implements Iterable<Forest.Body<T>> {
 
     /** assume that this forest contains exactly one tree and return it; otherwise throw an exception */
-    public final Tree<T> expand1() throws Parser.Ambiguous, Parser.Failed {
+    public final Tree<T> expand1() throws Ambiguous, ParseFailed {
         Iterator<Tree<T>> it = expand(true).iterator();
-        if (!it.hasNext()) throw new Parser.Failed();
+        if (!it.hasNext()) throw new ParseFailed();
         return it.next();
     }
 
     /** expand this forest into a set of trees */
-    public abstract HashSet<Tree<T>>  expand(boolean toss);
-
-    abstract boolean valid();
+    public HashSet<Tree<T>> expand(boolean toss) {
+        HashSet<Tree<T>> ret = new HashSet<Tree<T>>();
+        for(Body<T> b : this)
+            ret.addAll(b.expand(toss, new ArrayList<Tree<T>>(), 0, new HashSet<Tree<T>>()));
+        if (toss && ret.size() > 1) throw new Ambiguous(this);
+        return ret;
+    }
 
-    static <T> Forest<T>   singleton(Token.Location loc, Sequence creator)                       { return create(loc, null, new Forest[] { }, creator, false, true); }
-    static <T> Forest<T>   singleton(Token.Location loc, Forest<T> body, Sequence creator)       { return create(loc, null, new Forest[] { body }, creator, false, true); }
-    static <T> Forest<T>   leaf(Token.Location loc, T tag,                     Sequence creator) { return create(loc, tag, null, creator, false, false); }
-    public static <T> Forest<T>   create(Token.Location loc, T tag, Forest<T>[] tokens, Sequence creator, boolean unwrap, boolean singleton) {
-        return new MultiForest<T>(loc, tag, tokens, creator, unwrap, singleton);
+    static        <T> Forest<T> singleton(Input.Location loc)                       { return create(loc, null, new Forest[] { }, false, true); }
+    static        <T> Forest<T> singleton(Input.Location loc, Forest<T> body)       { return create(loc, null, new Forest[] { body },  false, true); }
+    static        <T> Forest<T> leaf(Input.Location loc, T tag) { return create(loc, tag, null, false, false); }
+    public static <T> Forest<T> create(Input.Location loc, T tag, Forest<T>[] tokens, boolean unwrap, boolean singleton) {
+        return new MyBody<T>(loc, tag, tokens, unwrap, singleton);
     }
 
     // Body //////////////////////////////////////////////////////////////////////////////
 
-    protected static class Body<T> {
+    protected static interface Body<T> {
+         HashSet<Tree<T>> expand(boolean toss, ArrayList<Tree<T>> toks, int i, HashSet<Tree<T>> h);
+    }
+
+    protected static class MyBody<T> extends Forest<T> implements Body<T> /* extends PrintableTree<Forest<T>> implements Iterable<Forest.Body<T>>*/ {
+        public Iterator<Body<T>> iterator() { return new SingletonIterator<Body<T>>(this); }
 
-        private final Token.Location    location;
+        private final Input.Location    location;
         private final T                 tag;
         private final Forest<T>[]       tokens;
-        private final Sequence          creator;
         private final boolean           unwrap;
         private final boolean           singleton;
 
-        private Body(Token.Location loc, T tag, Forest<T>[] tokens, Sequence creator, boolean unwrap, boolean singleton) {
+        private MyBody(Input.Location loc, T tag, Forest<T>[] tokens, boolean unwrap, boolean singleton) {
             this.location = loc;
             this.tag = tag;
             this.tokens = tokens==null ? emptyForestArray : new Forest[tokens.length];
             if (tokens != null) System.arraycopy(tokens, 0, this.tokens, 0, tokens.length);
             if (tokens != null) for(int i=0; i<tokens.length; i++) if (tokens[i]==null) throw new Error(i+"");
-            this.creator = creator;
             this.unwrap = unwrap;
             this.singleton = singleton;
         }
 
-        private HashSet<Tree<T>> expand(boolean toss, ArrayList<Tree<T>> toks, int i, HashSet<Tree<T>> h) {
+        public HashSet<Tree<T>> expand(boolean toss, ArrayList<Tree<T>> toks, int i, HashSet<Tree<T>> h) {
             if (singleton) {
-                for(Body<T> b : (IterableForest<T>)tokens[0]) b.expand(toss, toks, i, h);
+                for(Body<T> b : tokens[0]) b.expand(toss, toks, i, h);
 
             } else if (i==tokens.length) {
                 h.add(new Tree<T>(null, tag, toks.toArray(tree_hint)));
 
             } else if (unwrap && i==tokens.length-1) {
                 if (tokens[i] != null)
-                    for(Body b : (IterableForest<T>)tokens[i])
+                    for(Body b : tokens[i])
                         b.expand(toss, toks, 0, h);
 
             } else {
-                if (tokens[i]!=null) {
-                    HashSet<Tree<T>> exp = tokens[i].expand(toss);
-                    if (exp != null)
-                        for(Tree<T> r : exp) {
-                            int old = toks.size();
-                            toks.add(r);
-                            expand(toss, toks, i+1, h);
-                            while(toks.size() > old) toks.remove(toks.size()-1);
-                        }
+                boolean hit = false;
+                for(Tree<T> r : tokens[i].expand(toss)) {
+                    hit = true;
+                    int old = toks.size();
+                    toks.add(r);
+                    expand(toss, toks, i+1, h);
+                    while(toks.size() > old) toks.remove(toks.size()-1);
                 }
+                //if (!hit) throw new Error();
             }
             return h;
         }
-        void addTo(HashSet<Body> h) {
-            if (!singleton) h.add(this);
-            else for(Body b : (IterableForest<T>)tokens[0]) b.addTo(h);
-        }
-        void addTo(FastSet<Body> h) {
-            if (!singleton) h.add(this, true);
-            else for(Body b : (IterableForest<T>)tokens[0]) b.addTo(h);
-        }
 
-        private boolean kcache = false;
-        private boolean keep = false;
-        public boolean keep() {
-            return true;
-            /*
-            if (kcache) return keep;
-            kcache = true;
-            for(Forest<T> token : tokens) if (!token.valid()) return keep = false;
-            return keep = creator==null || (creator.needs.size()==0 && creator.hates.size()==0);
-            */
-        }
-        public boolean keep(Iterable<Body<T>> h) {
-            if (keep()) return true;
-            for(Forest<T> token : tokens) if (!token.valid()) return false;
-            int needs = 0;
-            for(Body<T> b : h) {
-                if (creator.hates.contains(b.creator) && b.keep(h)) return false;
-                if (creator.needs.contains(b.creator) && b.keep(h)) needs--;
-            }
-            return needs <= -1 * creator.needs.size();
-        }
-
-        private boolean rep = false;
-        public String toString() {
-            if (rep) return "***";
-            try {
-                rep = true;
-                StringBuffer ret = new StringBuffer();
-                for(int i=0; i<tokens.length; i++) {
-                    String q = tokens[i]==null ? "null" : tokens[i].toString();
-                    if (q.length() > 0) {
-                        ret.append(q);
-                        ret.append(" ");
-                    }
-                }
-                String tail = ret.toString().trim();
-                String head = (tag!=null && !tag.toString().equals("")) ? (tail.length() > 0 ? tag+":" : tag+"") : "";
-                if (tail.length() > 0) tail = "{" + tail + "}";
-                return head + tail;
-            } finally {
-                rep = false;
-            }
-        }
+        protected String  headToString()         { return null; }
+        protected String  headToJava()           { return null; }
+        protected String  left()                 { return "{"; }
+        protected String  right()                { return "}"; }
+        protected boolean ignoreSingleton()      { return false; }
     }
 
 
     // Ref //////////////////////////////////////////////////////////////////////////////
 
-    static abstract class IterableForest<T> extends Forest<T> implements Iterable<Forest.Body<T>> {
-        public abstract Iterator<Forest.Body<T>> iterator();
-    }
-
     /**
      *  This class represents a partially complete collection of
      *  forests to be viewed as a forest at some later date; once
      *  viewed, it becomes immutable
      */
-    static class Ref<T> extends IterableForest<T> {
-        private FastSet<Forest> hp = new FastSet<Forest>();
-        private Forest res = null;
-        public boolean valid = false;
+    static class Ref<T> extends Forest<T> {
+        private FastSet<Forest<T>> hp = new FastSet<Forest<T>>();
         public Ref() { }
-        public void merge(Forest p) {
-            //if (p==null) throw new Error("bad evil bad!");
-            if (res != null) throw new Error("already resolved!");
-            if (p==null) throw new Error();
-            if (p!=this) hp.add(p, true);
-        }
-        public Iterator<Body<T>> iterator() { return ((IterableForest<T>)resolve()).iterator(); }
-        public HashSet<Tree<T>> expand(boolean toss) { return resolve().expand(toss); }
-        public boolean valid() { return true; /*if (valid) return true; resolve(); return valid;*/ }
-        public String toString() { return resolve().toString(); }
-        public Forest resolve() {
-            if (hp==null) return res;
-            FastSet<Body> nh      = new FastSet<Body>();
-            /*
-            HashSet<Body> results = null;
-            for(Forest<?> p : hp)
-                for(Body<?> b : (IterableForest<?>)p) {
-                    if (b.keep() && (b.creator==null || !b.creator.lame)) {
-                        valid = true;
-                        b.addTo(nh);
-                    } else {
-                        results = new HashSet<Body>();
-                    }
+        public void merge(Forest p) { if (p!=this) hp.add(p, true); }
+        public Iterator<Body<T>> iterator() {
+            final Iterator<Forest<T>> ift = hp==null ? null : hp.iterator();
+            return new Iterator<Body<T>>() {
+                Iterator<Body<T>> ibt = ift==null ? null : ift.hasNext() ? ift.next().iterator() : null;
+                public void remove() { throw new RuntimeException("not supported"); }
+                public boolean hasNext() {
+                    if (ibt==null) return false;
+                    if (ibt.hasNext()) return true;
+                    ibt = ift.hasNext() ? ift.next().iterator() : null;
+                    return hasNext();
                 }
-            if (results != null) {
-                for(Forest<?> p : hp)
-                    for(Body<?> b : (IterableForest<?>)p)
-                        results.add(b);
-                for(Body b : results) {
-                    if (b.keep() && (b.creator==null || !b.creator.lame)) continue;
-                    if (b.creator!=null && b.creator.lame) continue;
-                    if (!b.keep(results)) continue;
-                    valid = true;
-                    b.addTo(nh);
+                public Body<T> next() {
+                    return ibt.next();
                 }
-            }
-            hp = null;
-            */
-            for(Forest<?> p : hp)
-                for(Body<?> b : (IterableForest<?>)p)
-                    if (b.creator==null || !b.creator.lame)
-                        b.addTo(nh);
-            res = new MultiForest(nh, nh.size()>0);
-            hp = null;
-            return res;
-        }
-    }
-
-    // Implementations //////////////////////////////////////////////////////////////////////////////
+            };
 
-    private static class MultiForest<T> extends IterableForest<T> {
-        private final FastSet<Body<T>> results;
-        private boolean valid;
-        public boolean valid() { /*return valid;*/ return true; }
-        private MultiForest(FastSet<Body<T>> results, boolean valid) { this.results = results; this.valid = valid; }
-        public MultiForest(Token.Location loc, T tag, Forest<T>[] tokens, Sequence creator, boolean unwrap, boolean singleton) {
-            this.results = new FastSet<Body<T>>(new Body(loc, tag, tokens, creator, unwrap, singleton));
-            this.valid = true;
-        }
-        public Iterator<Body<T>> iterator() { return results.iterator(); }
-
-        public HashSet<Tree<T>> expand(boolean toss) {
-            HashSet<Tree<T>> ret = new HashSet<Tree<T>>();
-            for(Body<T> b : results)
-                ret.addAll(b.expand(toss, new ArrayList<Tree<T>>(), 0, new HashSet<Tree<T>>()));
-            if (toss && ret.size() > 1) throw new Parser.Ambiguous(this);
-            return ret;
-        }
-        
-        // Display //////////////////////////////////////////////////////////////////////////////
-        
-        private String toString = null;
-        public String toString() {
-            if (toString != null) return toString;
-            StringBuffer ret = new StringBuffer();
-            if (results.size()==1) {
-                for(Forest.Body<T> r : results)
-                    ret.append(r);
-                return toString = ret.toString();
-            }
-            ret.append("<?");
-            boolean first = true;
-            for(Forest.Body<T> r : results) {
-                if (!first) ret.append(' ');
-                first = false;
-                ret.append(r);
-            }
-            ret.append("?>");
-            return toString = ret.toString();
         }
+        public Forest resolve() { return this; }
     }
 
+
     // Statics //////////////////////////////////////////////////////////////////////////////
 
     private static Tree[] tree_hint = new Tree[0];
-    private static Body[] body_hint = new Body[0];
     private static final Forest[] emptyForestArray = new Forest[0];
+
+    protected String  headToString()    { return null; }
+    protected String  headToJava()      { return null; }
+    protected String  left()            { return "<?"; }
+    protected String  right()           { return "?>"; }
+    protected boolean ignoreSingleton() { return true; }
 }