X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FSequence.java;h=8995b5c8576c96651d6d975037ec7822ebb3c28f;hb=72a191a1440fcdc484700238e8be1384ccc56e06;hp=328550dce3099319150949cbc2f83ea96c71bd1d;hpb=e214b29e31c1b1594695925eefc1fad411ce7081;p=sbp.git

diff --git a/src/edu/berkeley/sbp/Sequence.java b/src/edu/berkeley/sbp/Sequence.java
index 328550d..8995b5c 100644
--- a/src/edu/berkeley/sbp/Sequence.java
+++ b/src/edu/berkeley/sbp/Sequence.java
@@ -25,10 +25,10 @@ public abstract class Sequence extends Element implements Iterable<Element> {
     public static Sequence drop(Element[] e, boolean lame) { return new Constant.Drop(e, null, null, lame); }
 
     /** after matching the sequence, insert a constant into the output tree */
-    public static Sequence constant(Element[] e, Object o, HashSet<Sequence> and, HashSet<Sequence> not) { return new Constant(e, o, and, not); }
+    public static Sequence constant(Element[] e, Object o) { return new Constant(e, o, null, null); }
 
     /** 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, HashSet<Sequence> and, HashSet<Sequence> not) { return new Singleton(e, idx, and, not); }
+    public static Sequence singleton(Element[] e, int idx) { return new Singleton(e, idx, null, null); }
 
     /**
      *  after matching the sequence, create the specified output tree
@@ -36,8 +36,7 @@ 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, HashSet<Sequence> and, HashSet<Sequence> not) {
-        return new RewritingSequence(tag, e, drops, and, not); }
+    public static Sequence rewritingSequence(Object tag, Element[] e, boolean[] drops) { return new RewritingSequence(tag, e, drops, null, null); }
 
     ////////////////////////////////////////////////////////////////////////////////
 
@@ -53,10 +52,10 @@ public abstract class Sequence extends Element implements Iterable<Element> {
 
     protected final Element[] elements;
 
-          HashSet<Sequence> needed;
-          HashSet<Sequence> hated;
-    final HashSet<Sequence> needs;
-    final HashSet<Sequence> hates;
+    final HashSet<Sequence> needed = new HashSet<Sequence>();
+    final HashSet<Sequence> hated = new HashSet<Sequence>();
+    final HashSet<Sequence> needs = new HashSet<Sequence>();
+    final HashSet<Sequence> hates = new HashSet<Sequence>();
     public boolean           lame  = false;
 
     final Position          firstp;
@@ -64,14 +63,8 @@ public abstract class Sequence extends Element implements Iterable<Element> {
 
     public Iterator<Element> iterator()    { return new ArrayIterator<Element>(elements); }
     protected Sequence(Element[] elements, HashSet<Sequence> and, HashSet<Sequence> not) {
-        this.needs = and==null ? new HashSet<Sequence>() : and;
-        this.hates = not==null ? new HashSet<Sequence>() : not;
-        if (this.needs != null)
-            for(Sequence s : this.needs)
-                (s.needed==null?(s.needed=new HashSet<Sequence>()):s.needed).add(this);
-        if (this.hates != null)
-            for(Sequence s : this.hates)
-                (s.hated==null?(s.hated=new HashSet<Sequence>()):s.hated).add(this);
+        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); }
         this.elements = elements;
         this.firstp = new Position(0);
     }