diff -r 21b52310bd8b -r 7ea440e1ffbb testing4/re_test.sh
--- a/testing4/re_test.sh	Wed Nov 06 00:36:45 2019 +0000
+++ b/testing4/re_test.sh	Sat Nov 09 22:04:53 2019 +0000
@@ -113,6 +113,10 @@
   echo -e " simp(ONE | CHAR('a')) == (ONE | CHAR('a'))" >> $out
   echo -e " simp(ALT((CHAR('a') | ZERO) ~ ONE," >> $out
   echo -e "          ((ONE | CHAR('b')) | CHAR('c')) ~ (CHAR('d') ~ ZERO))) == CHAR('a')" >> $out
+  echo -e " simp((ZERO | ((ZERO | ZERO) | (ZERO | ZERO))) ~ ((ONE | ZERO) | ONE ) ~ (CHAR('a'))) == ZERO" >> $out
+  echo -e " simp(ALT(ONE | ONE, ONE | ONE)) == ONE" >> $out
+  echo -e " simp(ALT(ZERO | CHAR('a'), CHAR('a') | ZERO)) == CHAR('a')" >> $out
+  echo -e " simp(ALT(ONE | CHAR('a'), CHAR('a') | ONE)) == ALT(ONE | CHAR('a'), CHAR('a') | ONE)" >> $out
   if (scala_assert "re.scala" "re_test3.scala")
   then
     echo -e "  --> success" >> $out