isImmutableTyVar, isSkolemTyVar, isMetaTyVar, isMetaTyVarTy,
isSigTyVar, isExistentialTyVar, isTyConableTyVar,
metaTvRef,
- isFlexi, isIndirect, isRuntimeUnk, isUnk,
+ isFlexi, isIndirect, isUnkSkol, isRuntimeUnkSkol,
--------------------------------
-- Builders
| RuleSkol RuleName -- The LHS of a RULE
| GenSkol TcType -- Bound when doing a subsumption check for ty
+
| RuntimeUnkSkol -- a type variable used to represent an unknown
-- runtime type (used in the GHCi debugger)
isIndirect (Indirect _) = True
isIndirect _ = False
-isRuntimeUnk :: TyVar -> Bool
-isRuntimeUnk x | isTcTyVar x
- , SkolemTv RuntimeUnkSkol <- tcTyVarDetails x = True
- | otherwise = False
-
-isUnk :: TyVar -> Bool
-isUnk x | isTcTyVar x
- , SkolemTv UnkSkol <- tcTyVarDetails x = True
- | otherwise = 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
+
+isUnkSkol :: TyVar -> Bool
+isUnkSkol x | isTcTyVar x
+ , SkolemTv UnkSkol <- tcTyVarDetails x = True
+ | otherwise = False
\end{code}