Hugs: use custom versioon of unsafeInterleaveIO
#endif
#ifdef __HUGS__
-import Hugs.IOExts (unsafePerformIO)
+import Hugs.IOExts (unsafePerformIO, unsafeInterleaveIO)
#endif
#ifdef __NHC__
import NHC.Internal (unsafePerformIO)
#endif
-#ifndef __GLASGOW_HASKELL__
+#if !__GLASGOW_HASKELL__ && !__HUGS__
unsafeInterleaveIO :: IO a -> IO a
unsafeInterleaveIO f = return (unsafePerformIO f)
#endif