1 files changed, 20 insertions, 0 deletions
diff --git a/testsuite/tests/typecheck/should_compile/tc237.hs b/testsuite/tests/typecheck/should_compile/tc237.hs
new file mode 100644
index 0000000000..0eacf2e854
--- /dev/null
+++ b/testsuite/tests/typecheck/should_compile/tc237.hs
@@ -0,0 +1,20 @@
+{-# LANGUAGE RankNTypes, MultiParamTypeClasses, FunctionalDependencies #-}
+
+-- This one caught a bug in the implementation of functional
+-- dependencies, where improvement must happen when 
+-- checking the call in 'test4'
+
+module ShouldCompile where
+
+newtype M s a = M a       
+
+class Modular s a | s -> a
+
+wim ::  forall a w. Integral a 
+                      => a -> (forall s. Modular s a => M s w) -> w
+wim i k = error "urk"
+
+test4'  ::  (Modular s a, Integral a) => M s a
+test4'  =   error "urk"
+		       
+test4   =   wim 4 test4'