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diff --git a/testsuite/tests/typecheck/should_compile/FD2.hs b/testsuite/tests/typecheck/should_compile/FD2.hs
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+{-# LANGUAGE MultiParamTypeClasses, FunctionalDependencies #-}
+{-# LANGUAGE ScopedTypeVariables, FlexibleContexts #-}
+
+-- Trac #1783
+-- Like Trac #1781 you could argue that this one should succeed
+-- but we stick with the old behaviour for now.  When we do 
+-- fundeps properly it'll probably start to work
+
+module ShouldCompile where
+
+import Prelude hiding (foldr, foldr1)
+
+import Data.Maybe
+
+class Elem a e | a -> e
+
+class Foldable a where
+  foldr :: Elem a e => (e -> b -> b) -> b -> a -> b
+
+--  foldr1 :: forall e. Elem a e => (e -> e -> e) -> a -> e  -- WORKS!
+  foldr1 :: Elem a e => (e -> e -> e) -> a -> e
+  foldr1 f xs = fromMaybe (error "foldr1: empty structure")
+                  (foldr mf Nothing xs)
+     where mf :: Elem a e => (e -> Maybe e -> Maybe e)
+           mf x Nothing  = Just x
+           mf x (Just y) = Just (f x y)