fail

This package contains the "Control.Monad.Fail" module providing the <https://prime.haskell.org/wiki/Libraries/Proposals/MonadFail MonadFail> class that became available in <https://hackage.haskell.org/package/base-4.9.0.0 base-4.9.0.0> for older @base@ package versions. This package turns into an empty package when used with GHC versions which already provide the "Control.Monad.Fail" module to make way for GHC's own "Control.Monad.Fail" module.

cabal install fail

• base >=4.3 && <4.9

• 4.9.0.0