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-rw-r--r--testsuite/tests/arrows/should_compile/T3964.hs10
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diff --git a/testsuite/tests/arrows/should_compile/T3964.hs b/testsuite/tests/arrows/should_compile/T3964.hs
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+++ b/testsuite/tests/arrows/should_compile/T3964.hs
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+{-# LANGUAGE Arrows, ViewPatterns #-}
+
+module T3964 where
+
+import Control.Arrow
+
+testF :: Eq a => a -> (Maybe (Maybe a)) -> Maybe a
+testF v = proc x -> case x of
+ Just (Just ((==v) -> True)) -> returnA -< Just v
+ _ -> returnA -< Nothing