[project @ 2003-10-21 12:48:57 by simonpj]

Wibble to reporting duplicate instance decls

diff --git a/ghc/compiler/typecheck/Inst.lhs b/ghc/compiler/typecheck/Inst.lhs
index b742a4c..c07f806 100644 (file)
--- a/ghc/compiler/typecheck/Inst.lhs
+++ b/ghc/compiler/typecheck/Inst.lhs
@@ -62,7 +62,7 @@ import TcType ( Type, TcType, TcThetaType, TcTyVarSet,
                  tyVarsOfType, tyVarsOfTypes, tyVarsOfPred, tidyPred,
                  isClassPred, isTyVarClassPred, isLinearPred, 
                  getClassPredTys, getClassPredTys_maybe, mkPredName,
-                 isInheritablePred, isIPPred, 
+                 isInheritablePred, isIPPred, matchTys,
                  tidyType, tidyTypes, tidyFreeTyVars, tcSplitSigmaTy
                )
 import HscTypes        ( ExternalPackageState(..) )
@@ -77,11 +77,13 @@ import Subst        ( substTy, substTyWith, substTheta, mkTyVarSubst )
 import Literal ( inIntRange )
 import Var     ( TyVar )
 import VarEnv  ( TidyEnv, emptyTidyEnv, lookupSubstEnv, SubstResult(..) )
-import VarSet  ( elemVarSet, emptyVarSet, unionVarSet )
+import VarSet  ( elemVarSet, emptyVarSet, unionVarSet, mkVarSet )
 import TysWiredIn ( floatDataCon, doubleDataCon )
 import PrelNames       ( integerTyConName, fromIntegerName, fromRationalName, rationalTyConName )
 import BasicTypes( IPName(..), mapIPName, ipNameName )
 import UniqSupply( uniqsFromSupply )
+import CmdLineOpts( DynFlags )
+import Maybes  ( isJust )
 import Outputable
 \end{code}
 
@@ -556,7 +558,7 @@ checkNewInst :: DynFlags -> (InstEnv, InstEnv) -> DFunId -> TcM ()
 -- Check that the proposed new instance is OK
 checkNewInst dflags ies dfun
   = do {       -- Check functional dependencies
-         case checkFunDeps (home_ie, pkg_ie) dfun of
+         case checkFunDeps ies dfun of
                Just dfuns -> funDepErr dfun dfuns
                Nothing    -> return ()
 
@@ -564,9 +566,9 @@ checkNewInst dflags ies dfun
        ; mappM_ (dupInstErr dfun) dup_dfuns }
   where
     (tvs, _, cls, tys) = tcSplitDFunTy (idType dfun)
-    (matches, _) = lookupInstEnv dflags ies clas tys
+    (matches, _) = lookupInstEnv dflags ies cls tys
     dup_dfuns = [dfun | (_, (_, dup_tys, dup_dfun)) <- matches,
-                       isJust (matchTys tvs tys dup_tys)]
+                       isJust (matchTys (mkVarSet tvs) tys dup_tys)]
        -- Find memebers of the match list which 
        -- dfun itself matches. If the match is 2-way, it's a duplicate