[Haskell-beginners] combining two monads

[Ozgur Akgun]

Hi.

Daniel already answered the question; here is an alternative definition for
the loadConfig function he gave. Uses type-classes and liftIO. I find it
easier to use type-classes when dealing with monad transformers, especially
if you have more than a couple of them. You get automatic lifting for every
monad transformer in the stack except IO, for which you need to use liftIO.

Please ask if you have any questions.

loadConfig :: (MonadError MyError m, MonadIO m) => String -> m Config
loadConfig _ = do
  liftIO $ putStrLn "foo"
  throwError ConfigError

HTH,
Ozgur
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