X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2FUnion.java;h=334874285e7f83896b9db2c4338d32f399676e89;hp=99ef42b9aeadf14864c8e0563a76d8399596f909;hb=0e17670bcfa7b0fe8eb3a2cac81f4b080a09fc98;hpb=280e93a7eec101178dc81f8009eedb2916271f09

diff --git a/src/edu/berkeley/sbp/Union.java b/src/edu/berkeley/sbp/Union.java
index 99ef42b..3348742 100644
--- a/src/edu/berkeley/sbp/Union.java
+++ b/src/edu/berkeley/sbp/Union.java
@@ -7,46 +7,41 @@ import java.util.*;
 import java.lang.reflect.*;
 import java.lang.ref.*;
 
-/** an element which can produce one of several alternatives */
+/** <font color=green>an element which can produce one of several alternatives</font> */
 public class Union extends Element implements Iterable<Sequence> {
 
     private final String name;
     private final boolean synthetic;
+
     private final List<Sequence> alternatives = new ArrayList<Sequence>();
 
+    public Union(String name) { this(name, false); }
+
     /**
      *  Since every cycle in a non-degenerate grammar contains at
      *  least one Union, every instance of this class must be able to
      *  display itself in both "long form" (list of the long forms of
-     *  its alternatives) and "short form" (some abbreviation).
+     *  its alternatives) and "short form" (some name).
      *
-     *  @param shortForm the "short form" display; usually 
+     *  @param shortForm the "short form" display; for display purposes only
      *  @param synthetic if true, this Union's "long form" is "obvious" and should not be displayed when printing the grammar
      */
-    public Union() { this(null, false); }
-    public Union(String name) { this(name, false); }
     public Union(String name, boolean synthetic) {
         this.name = name;
         this.synthetic = synthetic;
     }
 
-    public Iterator<Sequence> iterator() { return alternatives.iterator(); }
     public boolean contains(Sequence s) { return alternatives.contains(s); }
+    public Iterator<Sequence> iterator() { return alternatives.iterator(); }
 
     /** adds an alternative */
     public void add(Sequence s) {
+        if (alternatives.contains(s)) return;
         alternatives.add(s);
-
-        // FIXME: does this make sense?
-        for(Sequence n : s.needs) add(n);
-        for(Sequence n : s.hates) add(n);
     }
 
-    // Epsilon Form //////////////////////////////////////////////////////////////////////////////
 
-    // FIXME
-    public static Union epsilon = new Union("()");
-    static { epsilon.add(Sequence.empty); }
+    // Epsilon Form //////////////////////////////////////////////////////////////////////////////
 
     // FIXME
     private Forest.Many epsilonForm = null;
@@ -61,6 +56,7 @@ public class Union extends Element implements Iterable<Sequence> {
         return epsilonForm;
     }
 
+
     // Display //////////////////////////////////////////////////////////////////////////////
 
     public String getName() {
@@ -93,7 +89,6 @@ public class Union extends Element implements Iterable<Sequence> {
     private void bodyToString(StringBuffer sb, String before, String between) {
         boolean first = true;
         for(Sequence s : this) {
-            if (s.lame) continue;
             // FIXME: what to do here about printing out negated sequences?
             sb.append(first ? before : between);
             first = false;