Just b -> return (Left b)
-- | Like 'finally', but only performs the final action if there was an
-- exception raised by the computation.
onException :: IO a -> IO b -> IO a
onException io what = io `catch` \e -> do _ <- what
Just b -> return (Left b)
-- | Like 'finally', but only performs the final action if there was an
-- exception raised by the computation.
onException :: IO a -> IO b -> IO a
onException io what = io `catch` \e -> do _ <- what