{-# LANGUAGE DataKinds #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE MonoLocalBinds #-}
module ContDo where

import GHC.TypeLits

(>>=) :: (a -> b) -> a -> b
(>>=) = ($)

class AlwaysFail a
instance TypeError (Text "fail") => AlwaysFail a

fail :: AlwaysFail a => String -> a
fail = error