X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcType.lhs;h=f266f4badbbfe80b529cd43dbb826bca1d1c949e;hb=8053aac536c96dabdc06e9f068852f5481474a29;hp=a3828082e387d9bbdb048c678dfd0d792101d37d;hpb=0b86bc9b022a5965d2b35f143ff4b919f784e676;p=ghc-hetmet.git

diff --git a/compiler/typecheck/TcType.lhs b/compiler/typecheck/TcType.lhs
index a382808..f266f4b 100644
--- a/compiler/typecheck/TcType.lhs
+++ b/compiler/typecheck/TcType.lhs
@@ -169,7 +169,8 @@ import Type		(	-- Re-exports
 			  pprType, pprParendType, pprTyThingCategory,
 			  pprPred, pprTheta, pprThetaArrow, pprClassPred
 			)
-import TyCon		( TyCon, isUnLiftedTyCon, isSynTyCon, synTyConDefn, tyConUnique )
+import TyCon		( TyCon, isUnLiftedTyCon, isSynTyCon, isOpenTyCon,
+			  synTyConDefn, tyConUnique )	 
 import DataCon		( DataCon, dataConStupidTheta, dataConResTys )
 import Class		( Class )
 import Var		( TyVar, Id, isCoVar, isTcTyVar, mkTcTyVar, tyVarName, tyVarKind, tcTyVarDetails )
@@ -343,6 +344,7 @@ data SkolemInfo
 	-- The rest are for non-scoped skolems
   | ClsSkol Class	-- Bound at a class decl
   | InstSkol Id		-- Bound at an instance decl
+  | FamInstSkol TyCon	-- Bound at a family instance decl
   | PatSkol DataCon	-- An existential type variable bound by a pattern for
 	    SrcSpan	-- a data constructor with an existential type. E.g.
 			--	data T = forall a. Eq a => MkT a
@@ -397,6 +399,7 @@ mkKindName unique = mkSystemName unique kind_var_occ
 
 kindVarRef :: KindVar -> IORef MetaDetails
 kindVarRef tc = 
+  ASSERT ( isTcTyVar tc )
   case tcTyVarDetails tc of
     MetaTv TauTv ref -> ref
     other            -> pprPanic "kindVarRef" (ppr tc)
@@ -470,7 +473,8 @@ pprSkolTvBinding :: TcTyVar -> SDoc
 -- Print info about the binding of a skolem tyvar, 
 -- or nothing if we don't have anything useful to say
 pprSkolTvBinding tv
-  = ppr_details (tcTyVarDetails tv)
+  = ASSERT ( isTcTyVar tv )
+    ppr_details (tcTyVarDetails tv)
   where
     ppr_details (MetaTv TauTv _)   = quotes (ppr tv) <+> ptext SLIT("is a meta type variable")
     ppr_details (MetaTv BoxTv _)   = quotes (ppr tv) <+> ptext SLIT("is a boxy type variable")
@@ -485,8 +489,13 @@ pprSkolTvBinding tv
 pprSkolInfo :: SkolemInfo -> SDoc
 pprSkolInfo (SigSkol ctxt)   = ptext SLIT("is bound by") <+> pprUserTypeCtxt ctxt
 pprSkolInfo (ClsSkol cls)    = ptext SLIT("is bound by the class declaration for") <+> quotes (ppr cls)
-pprSkolInfo (InstSkol df)    = ptext SLIT("is bound by the instance declaration at") <+> ppr (getSrcLoc df)
-pprSkolInfo (ArrowSkol loc)  = ptext SLIT("is bound by the arrow form at") <+> ppr loc
+pprSkolInfo (InstSkol df)    = 
+  ptext SLIT("is bound by the instance declaration at") <+> ppr (getSrcLoc df)
+pprSkolInfo (FamInstSkol tc) = 
+  ptext SLIT("is bound by the family instance declaration at") <+> 
+  ppr (getSrcLoc tc)
+pprSkolInfo (ArrowSkol loc)  = 
+  ptext SLIT("is bound by the arrow form at") <+> ppr loc
 pprSkolInfo (PatSkol dc loc) = sep [ptext SLIT("is bound by the pattern for") <+> quotes (ppr dc),
            		            nest 2 (ptext SLIT("at") <+> ppr loc)]
 pprSkolInfo (GenSkol tvs ty loc) = sep [sep [ptext SLIT("is bound by the polymorphic type"), 
@@ -591,8 +600,9 @@ isTauTy other		  = False
 
 isTauTyCon :: TyCon -> Bool
 -- Returns False for type synonyms whose expansion is a polytype
-isTauTyCon tc | isSynTyCon tc = isTauTy (snd (synTyConDefn tc))
-	      | otherwise     = True
+isTauTyCon tc 
+  | isSynTyCon tc && not (isOpenTyCon tc) = isTauTy (snd (synTyConDefn tc))
+  | otherwise                             = True
 
 ---------------
 isBoxyTy :: TcType -> Bool