Missing MonadFail (Kleisli m a)
instance MonadFail m => MonadFail (Kleisli m a) where
fail :: String -> Kleisli m a b
fail message = Kleisli \_ -> fail message
this would allow
-
data GHCi.UI.Monad.GHCi
to deriveMonadFail
viaKleisli Ghc (IORef GHCiSTate)
-
newtype Text.ParserCombinators.ReadPrec.ReadPrec
to deriveMonadFail
viaKleisli ReadP Prec
See #17993.