checkpoint

darcs-hash:20060115214901-5007d-2571b08f63af38515704f3af46c16d86999e2863.gz

diff --git a/src/edu/berkeley/sbp/Parser.java b/src/edu/berkeley/sbp/Parser.java
index 632729e..4c01e33 100644 (file)
--- a/src/edu/berkeley/sbp/Parser.java
+++ b/src/edu/berkeley/sbp/Parser.java
@@ -66,7 +66,7 @@ public abstract class Parser<Tok, Result> {
         public Table(String startSymbol, Topology top) { this(new Union(startSymbol), top); }
         public Table(Union ux, Topology top) {
             Union start0 = new Union("0");
-            start0.add(new Sequence.Singleton(ux, null, null));
+            start0.add(new Sequence.Singleton(ux));
 
             for(Sequence s : start0) cache.eof.put(s, true);
             cache.eof.put(start0, true);

diff --git a/src/edu/berkeley/sbp/Repeat.java b/src/edu/berkeley/sbp/Repeat.java
index aa91a64..bd0dbe0 100644 (file)
--- a/src/edu/berkeley/sbp/Repeat.java
+++ b/src/edu/berkeley/sbp/Repeat.java
@@ -36,10 +36,10 @@ public class Repeat extends Union {
             throw new RuntimeException("cannot create a maximal repetition of zero or more items with a separator (yet): " + this);
         if (zeroOkay) {
             add(new Sequence.Constant.Empty());
-            if (manyOkay) add(new Sequence.Singleton(many1(e, separator), null, null));
-            else          add(new Sequence.Singleton(e, null, null));
+            if (manyOkay) add(new Sequence.Singleton(many1(e, separator)));
+            else          add(new Sequence.Singleton(e));
         } else {
-            add(new Sequence.RewritingSequence(null, new Element[] { e }, null, null));
+            add(new Sequence.RewritingSequence(null, new Element[] { e }));
             if (separator==null)
                 add(new Sequence.Unwrap(new Element[] { e,                 Repeat.this }));
             else

diff --git a/src/edu/berkeley/sbp/Sequence.java b/src/edu/berkeley/sbp/Sequence.java
index 4caf800..32b8ba9 100644 (file)
--- a/src/edu/berkeley/sbp/Sequence.java
+++ b/src/edu/berkeley/sbp/Sequence.java
@@ -18,17 +18,23 @@ public abstract class Sequence extends Element implements Iterable<Element> {
     private void needs(Sequence s) { s.needed.add(this); needs.add(s); }
     private void hates(Sequence s) { s.hated.add(this); hates.add(s); }
 
+    void clone(Sequence seq) {
+        for(Sequence s : seq.hates) hates(s);
+        for(Sequence s : seq.needs) needs(s);
+        noFollow = seq.noFollow;
+    }
+
     /** the empty sequence (matches the empty string) */
     public static final Sequence empty = new Sequence.Constant.Empty();
 
     /** after matching the sequence, do not add anything to the output tree */
-    public static Sequence drop(Element[] e, boolean lame) { return new Constant.Drop(e, null, null, lame); }
+    public static Sequence drop(Element[] e, boolean lame) { return new Constant.Drop(e, lame); }
 
     /** after matching the sequence, insert a constant into the output tree */
-    public static Sequence constant(Element[] e, Object o) { return new Constant(e, o, null, null); }
+    public static Sequence constant(Element[] e, Object o) { return new Constant(e, o); }
 
     /** after matching the sequence, place the result of the <tt>idx</tt>th match in the output tree */
-    public static Sequence singleton(Element[] e, int idx) { return new Singleton(e, idx, null, null); }
+    public static Sequence singleton(Element[] e, int idx) { return new Singleton(e, idx); }
 
     /**
      *  after matching the sequence, create the specified output tree
@@ -36,7 +42,7 @@ public abstract class Sequence extends Element implements Iterable<Element> {
      *  @param e     the elements to match
      *  @param drops only elements of <tt>e</tt> whose corresponding <tt>boolean</tt> in <tt>drops</tt> is <i>false</i> will be included in the output tree
      **/
-    public static Sequence rewritingSequence(Object tag, Element[] e, boolean[] drops) { return new RewritingSequence(tag, e, drops, null, null); }
+    public static Sequence rewritingSequence(Object tag, Element[] e, boolean[] drops) { return new RewritingSequence(tag, e, drops); }
 
     ////////////////////////////////////////////////////////////////////////////////
 
@@ -62,10 +68,7 @@ public abstract class Sequence extends Element implements Iterable<Element> {
     Position firstp() { return firstp; }
 
     public Iterator<Element> iterator()    { return new ArrayIterator<Element>(elements); }
-    protected Sequence(Element[] elements) { this(elements, null, null); }
-    private Sequence(Element[] elements, HashSet<Sequence> and, HashSet<Sequence> not) {
-        if (and!=null) for(Sequence s : and) { needs.add(s); s.needed.add(this); }
-        if (not!=null) for(Sequence s : not) { hates.add(s); s.hated.add(this); }
+    protected Sequence(Element[] elements) {
         this.elements = elements;
         this.firstp = new Position(0);
     }
@@ -173,36 +176,38 @@ public abstract class Sequence extends Element implements Iterable<Element> {
 
     static class Constant extends Sequence {
         private final Object result;
-        public Constant(Element[] e, Object result, HashSet<Sequence> and, HashSet<Sequence> not) { super(e, and, not); this.result = result; }
-        public Sequence and(Sequence s) { Sequence ret = new Constant(elements, result, needs, hates); ret.needs(s); return ret; }
-        public Sequence not(Sequence s) { Sequence ret = new Constant(elements, result, needs, hates); ret.hates(s); return ret; }
+        public Constant(Element[] e, Object result) { super(e); this.result = result; }
+        public Sequence and(Sequence s) { Sequence ret = new Constant(elements, result); ret.needs(s); ret.clone(this); return ret; }
+        public Sequence not(Sequence s) { Sequence ret = new Constant(elements, result); ret.hates(s); ret.clone(this); return ret; }
         public <T> Forest<T> postReduce(Input.Location loc, Forest<T>[] args) {
             return (Forest<T>)Forest.leaf(loc, result);
         }
         static class Drop extends Constant {
-            public Drop(Element[] e, HashSet<Sequence> and, HashSet<Sequence> not, boolean lame) {
-                super(e, null, and, not);
+            public Drop(Element[] e, boolean lame) {
+                super(e, null);
                 this.lame = lame;
             }
+            public Sequence and(Sequence s) { Sequence ret = new Drop(elements, lame); ret.needs(s); ret.clone(this); return ret; }
+            public Sequence not(Sequence s) { Sequence ret = new Drop(elements, lame); ret.hates(s); ret.clone(this); return ret; }
         }
-        static class Empty extends Sequence.Constant.Drop { public Empty() { super(new Element[] { }, null, null, false); } }
+        static class Empty extends Sequence.Constant.Drop { public Empty() { super(new Element[] { }, false); } }
     }
 
     static class Singleton extends Sequence {
         private final int idx;
-        public Singleton(Element e, HashSet<Sequence> and, HashSet<Sequence> not) { this(new Element[] { e }, 0, and, not); }
-        public Singleton(Element[] e, int idx, HashSet<Sequence> and, HashSet<Sequence> not) { super(e, and, not); this.idx = idx; }
+        public Singleton(Element e) { this(new Element[] { e }, 0); }
+        public Singleton(Element[] e, int idx) { super(e); this.idx = idx; }
         public <T> Forest<T> postReduce(Input.Location loc, Forest<T>[] args) { return (Forest<T>)Forest.singleton(loc, args[idx]); }
-        public Sequence and(Sequence s) { Sequence ret = new Singleton(elements, idx, needs, hates); ret.needs(s); return ret; }
-        public Sequence not(Sequence s) { Sequence ret = new Singleton(elements, idx, needs, hates); ret.hates(s); return ret; }
+        public Sequence and(Sequence s) { Sequence ret = new Singleton(elements, idx); ret.needs(s); ret.clone(this); return ret; }
+        public Sequence not(Sequence s) { Sequence ret = new Singleton(elements, idx); ret.hates(s); ret.clone(this); return ret; }
     }
 
     public static class Unwrap extends Sequence {
         private boolean[] drops;
         public Unwrap(Element[] e)                  { super(e); this.drops = null; }
         public Unwrap(Element[] e, boolean[] drops) { super(e); this.drops = drops; }
-        public Sequence and(Sequence s) { Sequence ret = new Unwrap(elements, drops); ret.needs(s); return ret; }
-        public Sequence not(Sequence s) { Sequence ret = new Unwrap(elements, drops); ret.hates(s); return ret; }
+        public Sequence and(Sequence s) { Sequence ret = new Unwrap(elements, drops); ret.needs(s); ret.clone(this); return ret; }
+        public Sequence not(Sequence s) { Sequence ret = new Unwrap(elements, drops); ret.hates(s); ret.clone(this); return ret; }
         public <T> Forest<T> postReduce(Input.Location loc, Forest<T>[] args) {
             for(int i=0; i<args.length; i++) if (args[i]==null) throw new Error();
             if (drops==null) return Forest.create(loc, null, args, true, false);
@@ -219,11 +224,11 @@ public abstract class Sequence extends Element implements Iterable<Element> {
         /*private*/public final Object tag;
         private final boolean[] drops;
         private int count = 0;
-        public Sequence and(Sequence s) { Sequence ret = new RewritingSequence(tag, elements, drops, needs, hates); ret.needs(s); return ret; }
-        public Sequence not(Sequence s) { Sequence ret = new RewritingSequence(tag, elements, drops, needs, hates); ret.hates(s); return ret; }
-        public RewritingSequence(Object tag, Element[] e, HashSet<Sequence> and, HashSet<Sequence> not) { this(tag, e, null, and, not); }
-        public RewritingSequence(Object tag, Element[] e, boolean[] drops, HashSet<Sequence> and, HashSet<Sequence> not) {
-            super(e, and, not);
+        public Sequence and(Sequence s) { Sequence ret = new RewritingSequence(tag, elements, drops); ret.needs(s); ret.clone(this); return ret; }
+        public Sequence not(Sequence s) { Sequence ret = new RewritingSequence(tag, elements, drops); ret.hates(s); ret.clone(this); return ret; }
+        public RewritingSequence(Object tag, Element[] e) { this(tag, e, null); }
+        public RewritingSequence(Object tag, Element[] e, boolean[] drops) {
+            super(e);
             this.tag = tag;
             this.drops = drops == null ? new boolean[e.length] : drops;
             for(int i=0; i<this.drops.length; i++) if (!this.drops[i]) count++;