added arbitrary expression inversion, lookforward, and syntax for lookback

[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 bc6626a..3e9b2b6 100644 (file)
--- a/src/edu/berkeley/sbp/Repeat.java
+++ b/src/edu/berkeley/sbp/Repeat.java
@@ -20,6 +20,7 @@ public class Repeat extends Union {
     public  static Repeat many1(Element e)              { return new Repeat(e, false, true); }
     /** repeat one or more times, separated by <tt>sep</tt> */
     public  static Repeat many1(Element e, Element sep) { return new Repeat(e, false, true, sep); }
+
     /** repeat zero or more times, matching a maximal sequence of atoms */
     public  static Repeat maximal0(Element e)              { return new Repeat(e, true, true, null, true); }
     /** repeat one or more times, matching a maximal sequence of atoms */
@@ -43,24 +44,18 @@ public class Repeat extends Union {
         this.zeroOkay = zeroOkay;
         this.manyOkay = manyOkay;
         this.separator = separator;
-        Union who = this;
-        if (maximal) {
-            who = new Union(this+"++");
-            add(new Sequence.Singleton(who, null, null) {
-                    public Topology noFollow() { return separator==null ? e.toAtom() : separator.toAtom(); }
-                });
-        }
         if (zeroOkay) {
-            who.add(new Sequence.Constant.Empty());
-            if (manyOkay) who.add(new Sequence.Singleton(many1(e, separator), null, null));
-            else          who.add(new Sequence.Singleton(e, null, null));
+            add(new Sequence.Constant.Empty());
+            if (manyOkay) add(new Sequence.Singleton(many1(e, separator), null, null));
+            else          add(new Sequence.Singleton(e, null, null));
         } else {
-            who.add(new Sequence.RewritingSequence(null, new Element[] { e }, null, null));
+            add(new Sequence.RewritingSequence(null, new Element[] { e }, null, null));
             if (this.separator==null) {
-                who.add(new Sequence.Unwrap(new Element[] { e,                 Repeat.this }, null, null));
+                add(new Sequence.Unwrap(new Element[] { e,                 Repeat.this }, null, null));
             } else {
-                who.add(new Sequence.Unwrap(new Element[] { e, this.separator, Repeat.this }, new boolean[] { false, true, false }, null, null));
+                add(new Sequence.Unwrap(new Element[] { e, this.separator, Repeat.this }, new boolean[] { false, true, false }, null, null));
             }
         }
+        if (maximal) for(Sequence s : this) s.noFollow = separator==null ? e : separator;
     }
 }