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diff --git a/third_party/bazel/rules_haskell/examples/transformers/legacy/pre711/Control/Monad/IO/Class.hs b/third_party/bazel/rules_haskell/examples/transformers/legacy/pre711/Control/Monad/IO/Class.hs
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+++ b/third_party/bazel/rules_haskell/examples/transformers/legacy/pre711/Control/Monad/IO/Class.hs
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+{-# LANGUAGE CPP #-}
+#if __GLASGOW_HASKELL__ >= 702
+{-# LANGUAGE Safe #-}
+#endif
+#if __GLASGOW_HASKELL__ >= 708
+{-# LANGUAGE DeriveDataTypeable #-}
+{-# LANGUAGE StandaloneDeriving #-}
+#endif
+-----------------------------------------------------------------------------
+-- |
+-- Module      :  Control.Monad.IO.Class
+-- Copyright   :  (c) Andy Gill 2001,
+--                (c) Oregon Graduate Institute of Science and Technology, 2001
+-- License     :  BSD-style (see the file LICENSE)
+--
+-- Maintainer  :  R.Paterson@city.ac.uk
+-- Stability   :  experimental
+-- Portability :  portable
+--
+-- Class of monads based on @IO@.
+-----------------------------------------------------------------------------
+
+module Control.Monad.IO.Class (
+    MonadIO(..)
+  ) where
+
+#if __GLASGOW_HASKELL__ >= 708
+import Data.Typeable
+#endif
+
+-- | Monads in which 'IO' computations may be embedded.
+-- Any monad built by applying a sequence of monad transformers to the
+-- 'IO' monad will be an instance of this class.
+--
+-- Instances should satisfy the following laws, which state that 'liftIO'
+-- is a transformer of monads:
+--
+-- * @'liftIO' . 'return' = 'return'@
+--
+-- * @'liftIO' (m >>= f) = 'liftIO' m >>= ('liftIO' . f)@
+
+class (Monad m) => MonadIO m where
+    -- | Lift a computation from the 'IO' monad.
+    liftIO :: IO a -> m a
+
+#if __GLASGOW_HASKELL__ >= 708
+deriving instance Typeable MonadIO
+#endif
+
+instance MonadIO IO where
+    liftIO = id