1 files changed, 20 insertions, 0 deletions
diff --git a/compiler/ilxGen/tests/test13.hs b/compiler/ilxGen/tests/test13.hs
new file mode 100644
index 0000000000..559c8674fa
--- /dev/null
+++ b/compiler/ilxGen/tests/test13.hs
@@ -0,0 +1,20 @@
+class  NewFunctor f  where
+    inj         :: a -> f a
+    surj         :: f a -> a
+
+data N a = Z a 
+
+ninj x = (Z x) 
+nsurj (Z x) = x
+
+instance NewFunctor N where
+    inj = ninj
+    surj = nsurj
+
+twice :: NewFunctor f => a -> f (f a)
+twice x = inj(inj x)
+
+undo :: NewFunctor f => f (f a) -> a
+undo x = surj(surj x)
+
+main = putStr (undo (Z (Z "hello world\n")))