checkpoint

[sbp.git] / src / edu / berkeley / sbp / Repeat.java

diff --git a/src/edu/berkeley/sbp/Repeat.java b/src/edu/berkeley/sbp/Repeat.java
index b7e7e39..037e67d 100644 (file)
--- a/src/edu/berkeley/sbp/Repeat.java
+++ b/src/edu/berkeley/sbp/Repeat.java
@@ -16,10 +16,16 @@ class Repeat extends Union {
         this(e, zeroOkay, manyOkay, separator, false, tag); }
     protected Repeat(final Element e, boolean zeroOkay, boolean manyOkay, final Element separator, boolean maximal, Object tag) {
         super(e+(!manyOkay ? "?" : (zeroOkay ? (maximal ? "**" : "*") : (maximal ? "++" : "+")))+(separator==null?"":("/"+separator)), true);
-        if (zeroOkay) {
+        if (zeroOkay && !manyOkay) {
             add(new Sequence.Constant.Empty());
-            if (manyOkay) add(new Sequence.Singleton(Sequence.many1(e, separator)));
-            else          add(new Sequence.Singleton(e));
+            add(new Sequence.Singleton(e));
+            return;
+        }
+        if (zeroOkay) {
+            add(new Sequence.RewritingSequence(tag, new Element[] { }, null));
+            //add(new Sequence.Constant.Empty());
+            // FUGLY
+            add(new Sequence.Singleton(Sequence.many1(e, separator, tag)));
         } else {
             add(new Sequence.RewritingSequence(tag, new Element[] { e }, null));
             if (separator==null)
@@ -35,21 +41,13 @@ class Repeat extends Union {
             if (zeroOkay && separator != null)
                 throw new RuntimeException("cannot create a maximal repetition of zero or more items with a separator (yet): " + this);
             for(Sequence s : this)
-                s.follow = new Invert(separator);
+                s.follow = (Atom)separator.complement();
         }
         public Maximal(final Atom e, boolean zeroOkay, boolean manyOkay, Object tag) {
             super(e, zeroOkay, manyOkay, null, true, tag);
             for(Sequence s : this)
-                s.follow = new Invert(e);
+                s.follow = (Atom)e.complement();
         }
     }
 
-
-    /** an atom which tracks the inverse of some other atom */
-    private static class Invert<T extends Input> extends Atom<T> {
-        private final Atom<T> a;
-        public Invert(Atom<T> a) { this.a = a; }
-        public Topology<T> top() { return a.complement(); }
-        public String toString() { return "~"+a; }
-    }
 }