1 files changed, 22 insertions, 0 deletions
diff --git a/testsuite/tests/indexed-types/should_compile/T3208b.hs b/testsuite/tests/indexed-types/should_compile/T3208b.hs
new file mode 100644
index 0000000000..012756abd1
--- /dev/null
+++ b/testsuite/tests/indexed-types/should_compile/T3208b.hs
@@ -0,0 +1,22 @@
+{-# LANGUAGE TypeFamilies #-}
+
+-- This should fail
+
+module T3208b where
+  
+class SUBST s where
+    type STerm s
+
+class OBJECT o where
+    type OTerm o
+    apply :: (SUBST s, OTerm o ~ STerm s) => s -> o
+
+fce' :: (OTerm a ~ STerm a, OBJECT a, SUBST a) => a -> c
+fce' f = fce (apply f)
+-- f :: a
+-- apply f :: (OBJECT a, SUBST a, OTerm o ~ STerm a) => o
+-- fce called with a=o, gives wanted (OTerm o ~ STerm o, OBJECT o, SUBST o)
+
+
+fce :: (OTerm a ~ STerm a, OBJECT a, SUBST a) => a -> c
+fce f = fce' f