libghc-fail-doc 4.9.0.0-1 (amd64 binary) in ubuntu yakkety

 This package contains the "Control.Monad.Fail" module providing the MonadFail
 class that became available in base-4.9 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.
 .
 This package provides the documentation for a library for the Haskell
 programming language.
 See http://www.haskell.org/ for more information on Haskell.