Generalise Data.List/Control.Monad to Foldable/Traversable

This flips the switch and replaces the entities in
`Data.List`/`Control.Monad` conflicting with
`Data.{Foldable,Traversable}` with re-exports of the more general
versions.

As of this commit, the code below (which is also added as a test-case)
compiles w/o error.

    module XPrelude (module X) where

    import Control.Monad     as X
    import Data.Foldable     as X
    import Data.List         as X
    import Data.Monoid       as X
    import Data.Traversable  as X
    import Prelude           as X

This addresses #9568

Reviewed By: ekmett, austin

Differential Revision: https://phabricator.haskell.org/D235

1 files changed, 2 insertions, 7 deletions

diff --git a/libraries/base/Control/Monad.hs b/libraries/base/Control/Monad.hs
index c04c4a8f4d..561d40d135 100644
--- a/libraries/base/Control/Monad.hs
+++ b/libraries/base/Control/Monad.hs
@@ -78,9 +78,9 @@ module Control.Monad
 
 import Data.Foldable ( sequence_, msum, mapM_, forM_ )
 import Data.Functor ( void )
-import Data.Traversable ()
+import Data.Traversable ( forM, mapM, sequence )
 
-import GHC.Base
+import GHC.Base hiding ( mapM, sequence )
 import GHC.List ( zipWith, unzip, replicate )
 
 -- -----------------------------------------------------------------------------
@@ -101,11 +101,6 @@ filterM p (x:xs) =  do
    ys  <- filterM p xs
    return (if flg then x:ys else ys)
 
--- | 'forM' is 'mapM' with its arguments flipped
-forM            :: Monad m => [a] -> (a -> m b) -> m [b]
-{-# INLINE forM #-}
-forM            = flip mapM
-
 infixr 1 <=<, >=>
 
 -- | Left-to-right Kleisli composition of monads.