--- a/progs/re1.scala	Tue Sep 25 21:57:14 2018 +0100
+++ b/progs/re1.scala	Fri Sep 28 13:54:18 2018 +0100
@@ -131,6 +131,7 @@
 // derivatives might result into bigger and bigger
 // regular expressions...here is an example for this:
 
+// (a+b)* o a o b o (a+b)*
 val BIG_aux = STAR(ALT(CHAR('a'), CHAR('b')))
 val BIG = SEQ(BIG_aux, SEQ(CHAR('a'),SEQ(CHAR('b'), BIG_aux)))