--- a/progs/re1.scala	Fri Sep 27 15:43:25 2013 +0100
+++ b/progs/re1.scala	Mon Sep 30 13:18:16 2013 +0100
@@ -1,4 +1,5 @@
-    
+import scala.language.implicitConversions    
+
 abstract class Rexp
 
 case object NULL extends Rexp