make sure we track Input.Region for epsilon reductions (important for ambiguity-hunting)

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

diff --git a/src/edu/berkeley/sbp/Element.java b/src/edu/berkeley/sbp/Element.java
index 7eb6a59..f7a8978 100644 (file)
--- a/src/edu/berkeley/sbp/Element.java
+++ b/src/edu/berkeley/sbp/Element.java
@@ -16,6 +16,6 @@ public abstract class Element implements SequenceOrElement {
     abstract StringBuffer toString(StringBuffer sb);
 
     /** returns the Forest resulting from matching this element against the empty string */
-    Forest<?> epsilonForm() { throw new Error("element " + this + " has no epsilon form"); }
+    Forest<?> epsilonForm(Input.Region loc) { throw new Error("element " + this + " has no epsilon form"); }
 
 }