concrete functor and monad transformers
#20Urgent: PolyKinds is broken on GHC 7.4 breaking Data.Functor.Compose
In Data.Functor.Compose we have the line:
#if __GLASGOW_HASKELL__ >= 704
{-# LANGUAGE PolyKinds #-}
#endif
That needs to become
#if __GLASGOW_HASKELL__ >= 706
{-# LANGUAGE PolyKinds #-}
#endif
GHC's support for PolyKinds in 7.4 was buggy and leads to interface files that can't be loaded rendering that module broken on GHC 7.4 at present.