import Maybes ( catMaybes )
import Name ( getSrcLoc )
import ErrUtils ( ErrMsg, Message, addErrLocHdrLine, pprBagOfErrors, dontAddErrLoc )
-import Type ( mkFunTys, splitFunTys, splitAlgTyConApp_maybe,
+import Type ( mkFunTys, splitFunTys, splitAlgTyConApp_maybe, splitTyConApp_maybe,
isUnLiftedType, isTyVarTy, splitForAllTys, Type
)
import TyCon ( TyCon )
lintStgExpr e@(StgCase scrut _ _ bndr _ alts)
= lintStgExpr scrut `thenMaybeL` \ _ ->
- checkTys (idType bndr) scrut_ty (mkDefltMsg bndr) `thenL_`
+ (case alts of
+ StgPrimAlts tc _ _ -> check_bndr tc
+ StgAlgAlts (Just tc) _ _ -> check_bndr tc
+ StgAlgAlts Nothing _ _ -> returnL ()
+ ) `thenL_`
+
(trace (showSDoc (ppr e)) $
-- we only allow case of tail-call or primop.
(case scrut of
other -> addErrL (mkCaseOfCaseMsg e)) `thenL_`
addInScopeVars [bndr] (lintStgAlts alts scrut_ty)
- )
+ )
where
- scrut_ty = get_ty alts
-
- get_ty (StgAlgAlts ty _ _) = ty
- get_ty (StgPrimAlts ty _ _) = ty
+ scrut_ty = idType bndr
+ bad_bndr = mkDefltMsg bndr
+ check_bndr tc = case splitTyConApp_maybe scrut_ty of
+ Just (bndr_tc, _) -> checkL (tc == bndr_tc) bad_bndr
+ Nothing -> addErrL bad_bndr
\end{code}
\begin{code}