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diff --git a/ghc/compiler/rename/RenameMonad12.lhs b/ghc/compiler/rename/RenameMonad12.lhs
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+%
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1995
+%
+\section[RenameMonad12]{The monad used by the renamer passes 1 and 2}
+
+\begin{code}
+#include "HsVersions.h"
+
+module RenameMonad12 (
+	Rn12M(..),
+	initRn12, thenRn12, returnRn12,
+	mapRn12, zipWithRn12, foldrRn12,
+	addErrRn12, getModuleNameRn12, recoverQuietlyRn12,
+
+	-- and to make the interface self-sufficient...
+	Bag, Pretty(..), PprStyle, PrettyRep
+    ) where
+
+import Bag
+import Errors
+import Outputable
+import Pretty		-- for type Pretty
+import Util		-- for pragmas only
+
+infixr 9 `thenRn12`
+\end{code}
+
+In this monad, we pass down the name of the module we are working on,
+and we thread the collected errors.
+
+\begin{code}
+type Rn12M result
+  =  FAST_STRING{-module name-}
+  -> Bag Error
+  -> (result, Bag Error)
+
+#ifdef __GLASGOW_HASKELL__
+{-# INLINE thenRn12 #-}
+{-# INLINE returnRn12 #-}
+#endif
+
+initRn12 :: FAST_STRING{-module name-} -> Rn12M a -> (a, Bag Error)
+initRn12 mod action = action mod emptyBag
+
+thenRn12 :: Rn12M a -> (a -> Rn12M b) -> Rn12M b
+thenRn12 expr continuation mod errs_so_far
+  = case (expr mod errs_so_far) of
+     (res1, errs1) -> continuation res1 mod errs1
+
+returnRn12 :: a -> Rn12M a
+returnRn12 x mod errs_so_far = (x, errs_so_far)
+
+mapRn12 :: (a -> Rn12M b) -> [a] -> Rn12M [b]
+
+mapRn12 f []     = returnRn12 []
+mapRn12 f (x:xs)
+  = f x		 `thenRn12` \ r ->
+    mapRn12 f xs `thenRn12` \ rs ->
+    returnRn12 (r:rs)
+
+zipWithRn12 :: (a -> b -> Rn12M c) -> [a] -> [b] -> Rn12M [c]
+
+zipWithRn12 f []     [] = returnRn12 []
+zipWithRn12 f (x:xs) (y:ys)
+  = f x y	     	`thenRn12` \ r ->
+    zipWithRn12 f xs ys `thenRn12` \ rs ->
+    returnRn12 (r:rs)
+
+foldrRn12 :: (a -> b -> Rn12M b) -> b -> [a] -> Rn12M b
+
+foldrRn12 f z []     = returnRn12 z
+foldrRn12 f z (x:xs)
+ = foldrRn12 f z xs  `thenRn12` \ rest ->
+   f x rest
+
+addErrRn12 :: Error -> Rn12M ()
+addErrRn12 err mod errs_so_far
+ = ( (), errs_so_far `snocBag` err )
+
+getModuleNameRn12 :: Rn12M FAST_STRING
+getModuleNameRn12 mod errs_so_far = (mod, errs_so_far)
+\end{code}
+
+\begin{code}
+recoverQuietlyRn12 :: a -> Rn12M a -> Rn12M a
+
+recoverQuietlyRn12 use_this_if_err action mod errs_so_far
+  = let
+	(result, errs_out)
+	  = case (action mod emptyBag{-no errors-}) of { (res, errs) ->
+	    if isEmptyBag errs then
+		(res, errs_so_far)  -- retain incoming errs
+	    else
+		(use_this_if_err, errs_so_far)
+	    }
+    in
+    (result, errs_out)
+\end{code}