import Control.Exception
import Control.Exception.Annotation
import System.IO.Error

data Ann = Ann
  deriving (Show)

instance ExceptionAnnotation Ann

main :: IO ()
main = do
  catch
    (annotateIO Ann $ do
      throwIO (userError "kaas"))
    (\(e :: SomeException) -> putStrLn ("<<" ++ displayException e ++ ">>"))