[project @ 2005-07-19 16:44:50 by simonpj]

[ghc-hetmet.git] / ghc / compiler / typecheck / TcHsType.lhs

diff --git a/ghc/compiler/typecheck/TcHsType.lhs b/ghc/compiler/typecheck/TcHsType.lhs
index 54a909e..800fc8d 100644 (file)
--- a/ghc/compiler/typecheck/TcHsType.lhs
+++ b/ghc/compiler/typecheck/TcHsType.lhs
@@ -51,6 +51,7 @@ import Class          ( Class, classTyCon )
 import Name            ( Name, mkInternalName )
 import OccName         ( mkOccName, tvName )
 import NameSet
+import NameEnv
 import PrelNames       ( genUnitTyConName )
 import TysWiredIn      ( mkListTy, listTyCon, mkPArrTy, parrTyCon, tupleTyCon )
 import Bag             ( bagToList )
@@ -835,9 +836,8 @@ instance Outputable TcSigInfo where
        = ppr id <+> ptext SLIT("::") <+> ppr tyvars <+> ppr theta <+> ptext SLIT("=>") <+> ppr tau
 
 lookupSig :: [TcSigInfo] -> TcSigFun   -- Search for a particular signature
-lookupSig [] name = Nothing
-lookupSig (sig : sigs) name
-  | name == idName (sig_id sig) = Just sig
-  | otherwise                  = lookupSig sigs name
+lookupSig sigs = lookupNameEnv env
+  where
+    env = mkNameEnv [(idName (sig_id sig), sig) | sig <- sigs]
 \end{code}