--- a/progs/display/enfa.scala	Fri Apr 28 11:01:25 2017 +0100
+++ b/progs/display/enfa.scala	Sun May 07 00:20:58 2017 +0100
@@ -19,7 +19,7 @@
     applyOrElse(delta, (q, None))
 
   def enexts(qs: Set[A]) : Set[A] = 
-    qs | qs.flatMap(enext(_))
+    qs | qs.flatMap(enext(_))     // | is the set-union in Scala
 
   // epsilon closure
   def ecl(qs: Set[A]) : Set[A] =