diff -r fac25de665d2 -r d77af4aca939 marking/re1b_test.scala
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/marking/re1b_test.scala	Mon Dec 19 02:55:13 2016 +0000
@@ -0,0 +1,16 @@
+
+import scala.concurrent._
+import scala.concurrent.duration._
+import ExecutionContext.Implicits.global
+import scala.language.postfixOps 
+
+
+
+lazy val f = Future {
+  assert(der('a', ZERO | ONE) == (ZERO | ZERO))
+  assert(der('a', (CHAR('a') | ONE) ~ CHAR('a')) == ALT((ONE | ZERO) ~ CHAR('a'), ONE))
+  assert(der('a', STAR(CHAR('a'))) == (ONE ~ STAR(CHAR('a'))))
+  assert(der('b', STAR(CHAR('a'))) == (ZERO ~ STAR(CHAR('a'))))
+}
+
+Await.result(f, 120 second)