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diff --git a/testsuite/tests/typecheck/should_run/T2722.hs b/testsuite/tests/typecheck/should_run/T2722.hs
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+++ b/testsuite/tests/typecheck/should_run/T2722.hs
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+module Main (main, arid1, arid2) where
+
+import Prelude hiding (id, (.))
+import qualified Prelude
+import Control.Category
+import Control.Arrow
+import System.IO
+import Debug.Trace
+
+
+main = do { xs <- runXIOState arid1        -- Works with arid2
+          ; print xs }
+
+runXIOState :: IOSLA () c -> IO [c]
+runXIOState f = runIOSLA f ()
+
+newtype IOSLA a b = IOSLA { runIOSLA :: a -> IO [b] }
+
+instance Arrow IOSLA where
+    arr f = IOSLA $ \ x -> return [f x]
+
+instance Category IOSLA where
+    id = arr id
+
+-- arr :: Arrow m => (b->c) -> m b c
+-- id  :: Category m => m b b
+-- (arr id) :: Arrow m => m a a
+
+arid1 :: Arrow m => m a a
+arid1 = arr id
+
+arid2 :: Arrow m => m a a
+arid2 = arr Prelude.id
+