Doing the smart canonicalization only if we are not simplifying a Rule LHS.

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

diff --git a/compiler/typecheck/TcType.lhs b/compiler/typecheck/TcType.lhs
index 7410092..b2da9f0 100644 (file)
--- a/compiler/typecheck/TcType.lhs
+++ b/compiler/typecheck/TcType.lhs
@@ -339,9 +339,6 @@ data SkolemInfo
   | RuntimeUnkSkol      -- a type variable used to represent an unknown
                         -- runtime type (used in the GHCi debugger)
 
-  | NoScSkol           -- Used for the "self" superclass when solving
-                       -- superclasses; don't generate superclasses of me
-
   | UnkSkol            -- Unhelpful info (until I improve it)
 
 -------------------------------------
@@ -451,6 +448,9 @@ pprSkolTvBinding tv
                                   sep [pprSkolInfo info, 
                                        nest 2 (ptext (sLit "at") <+> ppr (getSrcLoc tv))]]
  
+instance Outputable SkolemInfo where
+  ppr = pprSkolInfo
+
 pprSkolInfo :: SkolemInfo -> SDoc
 -- Complete the sentence "is a rigid type variable bound by..."
 pprSkolInfo (SigSkol ctxt)  = pprUserTypeCtxt ctxt
@@ -458,7 +458,6 @@ pprSkolInfo (IPSkol ips)    = ptext (sLit "the implicit-parameter bindings for")
                               <+> pprWithCommas ppr ips
 pprSkolInfo (ClsSkol cls)   = ptext (sLit "the class declaration for") <+> quotes (ppr cls)
 pprSkolInfo InstSkol        = ptext (sLit "the instance declaration")
-pprSkolInfo NoScSkol        = ptext (sLit "the instance declaration (self)")
 pprSkolInfo FamInstSkol     = ptext (sLit "the family instance declaration")
 pprSkolInfo (RuleSkol name) = ptext (sLit "the RULE") <+> doubleQuotes (ftext name)
 pprSkolInfo ArrowSkol       = ptext (sLit "the arrow form")
@@ -673,14 +672,10 @@ isIndirect _            = False
 
 isRuntimeUnkSkol :: TyVar -> Bool
 -- Called only in TcErrors; see Note [Runtime skolems] there
-isRuntimeUnkSkol x 
-  | isTcTyVar x
-  , SkolemTv info <- tcTyVarDetails x 
-  = case info of 
-       UnkSkol -> True
-       RuntimeUnkSkol -> True
-       _ -> False
-  | otherwise = False
+isRuntimeUnkSkol x | isTcTyVar x
+                  , SkolemTv RuntimeUnkSkol <- tcTyVarDetails x 
+                  = True
+                  | otherwise = False
 
 isUnkSkol :: TyVar -> Bool
 isUnkSkol x | isTcTyVar x
@@ -1026,8 +1021,6 @@ getClassPredTys _ = panic "getClassPredTys"
 mkDictTy :: Class -> [Type] -> Type
 mkDictTy clas tys = mkPredTy (ClassP clas tys)
 
-
-
 isDictLikeTy :: Type -> Bool
 -- Note [Dictionary-like types]
 isDictLikeTy ty | Just ty' <- tcView ty = isDictTy ty'