classy prelude fail

gistfile1.txt

ClassyPrelude.hs:234:9:
    Could not deduce (a ~ ())
    from the context (Monad m, MonoFoldable c)
      bound by the type signature for
                 mapM_ :: (Monad m, MonoFoldable c) =>
                          (Element c -> m a) -> c -> m ()
      at ClassyPrelude.hs:233:10-69
      `a' is a rigid type variable bound by
          the type signature for
            mapM_ :: (Monad m, MonoFoldable c) =>
                     (Element c -> m a) -> c -> m ()
          at ClassyPrelude.hs:233:10
    Expected type: (Element c -> m a) -> c -> m ()
      Actual type: (Element c -> m ()) -> c -> m ()
    In the expression: omapM_
    In an equation for `mapM_': mapM_ = omapM_

ClassyPrelude.hs:237:9:
    Could not deduce (a ~ ())
    from the context (Monad m, MonoFoldable c)
      bound by the type signature for
                 forM_ :: (Monad m, MonoFoldable c) =>
                          c -> (Element c -> m a) -> m ()
      at ClassyPrelude.hs:236:10-69
      `a' is a rigid type variable bound by
          the type signature for
            forM_ :: (Monad m, MonoFoldable c) =>
                     c -> (Element c -> m a) -> m ()
          at ClassyPrelude.hs:236:10
    Expected type: c -> (Element c -> m a) -> m ()
      Actual type: c -> (Element c -> m ()) -> m ()
    In the expression: oforM_
    In an equation for `forM_': forM_ = oforM_