[commit: ghc] master: Revert "Eta-expand argument to foldr in mapM_ for []" (91d9530)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/91d9530525803403c3c012901115d54ff4fc3b5e/ghc

>---------------------------------------------------------------

commit 91d9530525803403c3c012901115d54ff4fc3b5e
Author: Austin Seipp <austin at well-typed.com>
Date:   Tue Feb 17 09:08:12 2015 -0600

    Revert "Eta-expand argument to foldr in mapM_ for []"
    
    This change lacked justification (or a test!) for its improvements, and
    I merged it on a sweep of Phabricator without fixing this. Trac #10034.
    
    This reverts commit 7cf87fc6928f0252d9f61719e2344e6c69237079.


>---------------------------------------------------------------

91d9530525803403c3c012901115d54ff4fc3b5e
 libraries/base/Data/Foldable.hs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/libraries/base/Data/Foldable.hs b/libraries/base/Data/Foldable.hs
index b8b0973..a745f66 100644
--- a/libraries/base/Data/Foldable.hs
+++ b/libraries/base/Data/Foldable.hs
@@ -349,8 +349,7 @@ for_ = flip traverse_
 -- As of base 4.8.0.0, 'mapM_' is just 'traverse_', specialized to
 -- 'Monad'.
 mapM_ :: (Foldable t, Monad m) => (a -> m b) -> t a -> m ()
-{-# INLINE mapM_ #-}
-mapM_ f = foldr (\m n -> f m >> n) (return ())
+mapM_ f= foldr ((>>) . f) (return ())
 
 -- | 'forM_' is 'mapM_' with its arguments flipped. For a version that
 -- doesn't ignore the results see 'Data.Traversable.forM'.