You can't do that; sorry. You can always turn a string into an IOException if you like. Or you could write a wrapper around IO. But MonadError has a functional dependency, so you can only have one error type per monad.
Is it possible?However I also need to make it an instance of MonadError String...Hello,IO is an instance of MonadError IOException...I'm trying to instanciate this class:
class (Typeable n, Monad n, Applicative n, MonadError String n) => EvMgt n where ...instance EvMgt IO where...Any idea?
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