diff -r ed1b6b8c36e5 -r 0b727d1a8184 main_testing3/re_test4.scala
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main_testing3/re_test4.scala	Mon Nov 02 02:31:44 2020 +0000
@@ -0,0 +1,19 @@
+import CW8c._
+
+val EVIL_urban = SEQ(STAR(STAR(CHAR('a'))), CHAR('b'))
+
+assert(ders(("a" * 5).toList, EVIL_urban) == SEQ(SEQ(STAR(CHAR('a')),STAR(STAR(CHAR('a')))),CHAR('b')))
+assert(ders(List('b'), EVIL_urban) == ONE)
+assert(ders(List('b','b'), EVIL_urban) == ZERO)
+assert(matcher(EVIL_urban, "a" * 5 ++ "b") == true)
+assert(matcher(EVIL_urban, "a" * 50 ++ "b") == true)
+assert(matcher(EVIL_urban, "a" * 50) == false)
+assert(matcher(EVIL_urban, "b") == true)
+assert(matcher(EVIL_urban, "bb") == false)
+assert(matcher("abc", "abc") == true)
+assert(matcher("abc", "ab") == false)
+assert(matcher(("ab" | "a") ~ (ONE | "bc"), "abc") == true)
+assert(matcher(ONE, "") == true)
+assert(matcher(ZERO, "") == false)
+assert(matcher(ONE | CHAR('a'), "") == true)
+assert(matcher(ONE | CHAR('a'), "a") == true)