-- Checks that the type is valid for the given context
checkValidType ctxt ty
= traceTc (text "checkValidType" <+> ppr ty) `thenM_`
- doptM Opt_GlasgowExts `thenM` \ gla_exts ->
+ doptM Opt_UnboxedTuples `thenM` \ unboxed ->
doptM Opt_Rank2Types `thenM` \ rank2 ->
doptM Opt_RankNTypes `thenM` \ rankn ->
doptM Opt_PolymorphicComponents `thenM` \ polycomp ->
ForSigCtxt _ -> isLiftedTypeKind actual_kind
other -> isSubArgTypeKind actual_kind
- ubx_tup | not gla_exts = UT_NotOk
- | otherwise = case ctxt of
- TySynCtxt _ -> UT_Ok
- ExprSigCtxt -> UT_Ok
- other -> UT_NotOk
- -- Unboxed tuples ok in function results,
- -- but for type synonyms we allow them even at
- -- top level
+ ubx_tup = case ctxt of
+ TySynCtxt _ | unboxed -> UT_Ok
+ ExprSigCtxt | unboxed -> UT_Ok
+ _ -> UT_NotOk
in
-- Check that the thing has kind Type, and is lifted if necessary
checkTc kind_ok (kindErr actual_kind) `thenM_`
}
| isUnboxedTupleTyCon tc
- = doptM Opt_GlasgowExts `thenM` \ gla_exts ->
- checkTc (ubx_tup_ok gla_exts) ubx_tup_msg `thenM_`
+ = doptM Opt_UnboxedTuples `thenM` \ ub_tuples_allowed ->
+ checkTc (ubx_tup_ok ub_tuples_allowed) ubx_tup_msg `thenM_`
mappM_ (check_tau_type (Rank 0) UT_Ok) tys
-- Args are allowed to be unlifted, or
-- more unboxed tuples, so can't use check_arg_ty
= mappM_ check_arg_type tys
where
- ubx_tup_ok gla_exts = case ubx_tup of { UT_Ok -> gla_exts; other -> False }
+ ubx_tup_ok ub_tuples_allowed = case ubx_tup of { UT_Ok -> ub_tuples_allowed; other -> False }
n_args = length tys
tc_arity = tyConArity tc
other -> flexible_contexts || all tyvar_head tys
where
flexible_contexts = dopt Opt_FlexibleContexts dflags
- undecidable_ok = dopt Opt_AllowUndecidableInstances dflags
+ undecidable_ok = dopt Opt_UndecidableInstances dflags
-------------------------
tyvar_head ty -- Haskell 98 allows predicates of form
\begin{code}
checkValidInstance :: [TyVar] -> ThetaType -> Class -> [TcType] -> TcM ()
checkValidInstance tyvars theta clas inst_tys
- = do { gla_exts <- doptM Opt_GlasgowExts
- ; undecidable_ok <- doptM Opt_AllowUndecidableInstances
+ = do { undecidable_ok <- doptM Opt_UndecidableInstances
; checkValidTheta InstThetaCtxt theta
; checkAmbiguity tyvars theta (tyVarsOfTypes inst_tys)
-- Check that instance inference will terminate (if we care)
- -- For Haskell 98, checkValidTheta has already done that
- ; when (gla_exts && not undecidable_ok) $
+ -- For Haskell 98 this will already have been done by checkValidTheta,
+ -- but as we may be using other extensions we need to check.
+ ; unless undecidable_ok $
mapM_ addErrTc (checkInstTermination inst_tys theta)
-- The Coverage Condition