X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcDeriv.lhs;h=2edd8361058480088578edd57eba6f22d0a69acf;hb=4c6a3f787abcaed009a574196d82237d9ae64fc8;hp=e79318b587700a97e8f585a487785337f47cf0bc;hpb=162ae90572443ca726992ea54f4cbc75658453d3;p=ghc-hetmet.git

diff --git a/compiler/typecheck/TcDeriv.lhs b/compiler/typecheck/TcDeriv.lhs
index e79318b..2edd836 100644
--- a/compiler/typecheck/TcDeriv.lhs
+++ b/compiler/typecheck/TcDeriv.lhs
@@ -46,6 +46,7 @@ import SrcLoc
 import Util
 import ListSetOps
 import Outputable
+import FastString
 import Bag
 \end{code}
 
@@ -265,7 +266,7 @@ tcDeriving  :: [LTyClDecl Name]  -- All type constructors
 		    HsValBinds Name)	-- Extra generated top-level bindings
 
 tcDeriving tycl_decls inst_decls deriv_decls
-  = recoverM (returnM ([], emptyValBindsOut)) $
+  = recoverM (return ([], emptyValBindsOut)) $
     do	{   	-- Fish the "deriving"-related information out of the TcEnv
 		-- And make the necessary "equations".
 	; early_specs <- makeDerivSpecs tycl_decls inst_decls deriv_decls
@@ -286,8 +287,8 @@ tcDeriving tycl_decls inst_decls deriv_decls
 	; let inst_info = insts1 ++ insts2
 
 	; dflags <- getDOpts
-	; ioToTcRn (dumpIfSet_dyn dflags Opt_D_dump_deriv "Derived instances" 
-	  	   (ddump_deriving inst_info rn_binds))
+	; liftIO (dumpIfSet_dyn dflags Opt_D_dump_deriv "Derived instances"
+	         (ddump_deriving inst_info rn_binds))
 
 	; return (inst_info, rn_binds) }
   where
@@ -798,10 +799,10 @@ mkNewTypeEqn orig mayDeriveDataTypeable newtype_deriving tvs
 		-- Want to drop 1 arg from (T s a) and (ST s a)
 		-- to get 	instance Monad (ST s) => Monad (T s)
 
-	-- Note [newtype representation]
-	-- Need newTyConRhs *not* newTyConRep to get the representation 
-	-- type, because the latter looks through all intermediate newtypes
-	-- For example
+	-- Note [Newtype representation]
+	-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+	-- Need newTyConRhs (*not* a recursive representation finder) 
+	-- to get the representation type. For example
 	--	newtype B = MkB Int
 	--	newtype A = MkA B deriving( Num )
 	-- We want the Num instance of B, *not* the Num instance of Int,