checkpoint

[sbp.git] / src / edu / berkeley / sbp / meta / MetaGrammarBindings.java

diff --git a/src/edu/berkeley/sbp/meta/MetaGrammarBindings.java b/src/edu/berkeley/sbp/meta/MetaGrammarBindings.java
index e3299cb..0d9052c 100644 (file)
--- a/src/edu/berkeley/sbp/meta/MetaGrammarBindings.java
+++ b/src/edu/berkeley/sbp/meta/MetaGrammarBindings.java
@@ -92,7 +92,7 @@ public class MetaGrammarBindings extends AnnotationGrammarBindings {
 
         try {
             Tree t = new CharParser(MetaGrammar.newInstance()).parse(new FileInputStream("tests/"+fileName)).expand1();
-            Tree.TreeFunctor<Object,Object> red = (Tree.TreeFunctor<Object,Object>)t.head();
+            TreeFunctor<Object,Object> red = (TreeFunctor<Object,Object>)t.head();
             String oldprefix = prefix;
             prefix = as;
             GrammarNode gn = (GrammarNode)red.invoke(t);
@@ -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;
@@ -394,7 +397,7 @@ public class MetaGrammarBindings extends AnnotationGrammarBindings {
         }
         public Context(Tree t, Grammar.Bindings rm) {
             this.rm = rm;
-            Tree.TreeFunctor<Object,Object> red = (Tree.TreeFunctor<Object,Object>)t.head();
+            TreeFunctor<Object,Object> red = (TreeFunctor<Object,Object>)t.head();
             this.grammar = (GrammarNode)red.invoke(t);
         }
         public Union peek(String name) { return map.get(name); }