1 files changed, 16 insertions, 0 deletions
diff --git a/testsuite/tests/indexed-types/should_compile/Col.hs b/testsuite/tests/indexed-types/should_compile/Col.hs
new file mode 100644
index 0000000000..62c309bd91
--- /dev/null
+++ b/testsuite/tests/indexed-types/should_compile/Col.hs
@@ -0,0 +1,16 @@
+{-# LANGUAGE TypeFamilies #-}
+
+module Col  where 
+
+type family Elem c
+
+type instance Elem [e] = e
+
+class Col c where
+ singleton :: Elem c -> c
+ add :: c -> Elem c -> c
+
+instance Col [e] where
+ singleton = \x -> [x]
+ add = flip (:)
+