X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcEnv.lhs;h=63b73fcbf6e83fe8c002e67a6faaf3c0dcabde29;hb=f8c52d7fde2d7408b4f734251c373f8d3e2c558e;hp=dfdf58e04a16062b8665eb504114ff1c62cd3ba3;hpb=17b297d97d327620ed6bfab942f8992b2446f1bf;p=ghc-hetmet.git

diff --git a/compiler/typecheck/TcEnv.lhs b/compiler/typecheck/TcEnv.lhs
index dfdf58e..63b73fc 100644
--- a/compiler/typecheck/TcEnv.lhs
+++ b/compiler/typecheck/TcEnv.lhs
@@ -3,11 +3,11 @@
 %
 
 \begin{code}
-{-# OPTIONS_GHC -w #-}
+{-# OPTIONS -w #-}
 -- The above warning supression flag is a temporary kludge.
 -- While working on this module you are encouraged to remove it and fix
 -- any warnings in the module. See
---     http://hackage.haskell.org/trac/ghc/wiki/WorkingConventions#Warnings
+--     http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
 -- for details
 
 module TcEnv(
@@ -635,30 +635,20 @@ iDFunId info = instanceDFunId (iSpec info)
 
 data InstBindings
   = VanillaInst 		-- The normal case
-	(LHsBinds Name)		-- Bindings
+	(LHsBinds Name)		-- Bindings for the instance methods
 	[LSig Name]		-- User pragmas recorded for generating 
 				-- specialised instances
 
   | NewTypeDerived              -- Used for deriving instances of newtypes, where the
 				-- witness dictionary is identical to the argument 
 				-- dictionary.  Hence no bindings, no pragmas.
-	(Maybe [PredType])
-		-- Nothing      => The newtype-derived instance involves type variables,
-		--	           and the dfun has a type like df :: forall a. Eq a => Eq (T a)
-		-- Just (r:scs) => The newtype-defined instance has no type variables
-		--		   so the dfun is just a constant, df :: Eq T
-		-- 		   In this case we need to know waht the rep dict, r, and the 
-		--		   superclasses, scs, are.  (In the Nothing case these are in the
-		--		   dict fun's type.)
-		--		   Invariant: these PredTypes have no free variables
-		-- NB: In both cases, the representation dict is the *first* dict.
 
 pprInstInfo info = vcat [ptext SLIT("InstInfo:") <+> ppr (idType (iDFunId info))]
 
 pprInstInfoDetails info = pprInstInfo info $$ nest 2 (details (iBinds info))
   where
-    details (VanillaInst b _)  = pprLHsBinds b
-    details (NewTypeDerived _) = text "Derived from the representation type"
+    details (VanillaInst b _) = pprLHsBinds b
+    details NewTypeDerived    = text "Derived from the representation type"
 
 simpleInstInfoClsTy :: InstInfo -> (Class, Type)
 simpleInstInfoClsTy info = case instanceHead (iSpec info) of