X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2Fmeta%2FMetaGrammarBindings.java;h=0d9052c7efadaed93fb6a0368808727c3aafa098;hp=8f322a545937a665a127245da76b3b6f9de171f7;hb=38eb7943a4be918d46cb6517004e57ca91410ce0;hpb=280e93a7eec101178dc81f8009eedb2916271f09

diff --git a/src/edu/berkeley/sbp/meta/MetaGrammarBindings.java b/src/edu/berkeley/sbp/meta/MetaGrammarBindings.java
index 8f322a5..0d9052c 100644
--- a/src/edu/berkeley/sbp/meta/MetaGrammarBindings.java
+++ b/src/edu/berkeley/sbp/meta/MetaGrammarBindings.java
@@ -265,7 +265,10 @@ public class MetaGrammarBindings extends AnnotationGrammarBindings {
     public static @bind.as        Seq  psx(Seq s)                        { return s; }
     public static @bind.as(":")   ElementNode   colon(String s, ElementNode e)             { return new Label(s, e); }
     public static @bind.as(")")   void close(String foo)                 { throw new Error("not supported"); }
-    public static @bind.as("()")  ElementNode   epsilon()                         { return new Constant(Union.epsilon); }
+    public static @bind.as("()")  ElementNode   epsilon()                         { return new Constant(epsilon); }
+
+    private static Union epsilon = new Union("()");
+    static { epsilon.add(Sequence.empty); }
 
     public static class NonTerminalReferenceNode extends ElementNode {
         public String nonTerminal;