X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcIfaceSig.lhs;h=b922e6285250de99ac039ab467feac9ed890bd96;hb=d68887047bcfb9021151f768fe1a22df2d3fbe1e;hp=1218e41350bc7f5da38e05cb70a693922fcf5593;hpb=996573cd62a9dab5b3a7f7ab85567507422601bb;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcIfaceSig.lhs b/ghc/compiler/typecheck/TcIfaceSig.lhs index 1218e41..b922e62 100644 --- a/ghc/compiler/typecheck/TcIfaceSig.lhs +++ b/ghc/compiler/typecheck/TcIfaceSig.lhs @@ -1,47 +1,44 @@ % -% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996 +% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % \section[TcIfaceSig]{Type checking of type signatures in interface files} \begin{code} -module TcIfaceSig ( tcInterfaceSigs ) where +module TcIfaceSig ( tcInterfaceSigs, tcVar, tcCoreExpr, tcCoreLamBndrs ) where #include "HsVersions.h" -import HsSyn ( HsDecl(..), IfaceSig(..) ) +import HsSyn ( TyClDecl(..), HsTupCon(..) ) import TcMonad -import TcMonoType ( tcHsType, tcHsTypeKind ) -import TcEnv ( tcExtendTyVarEnv, tcExtendGlobalValEnv, - tcLookupTyConByKey, tcLookupGlobalValueMaybe, - tcExplicitLookupGlobal +import TcMonoType ( tcIfaceType ) +import TcEnv ( RecTcEnv, tcExtendTyVarEnv, + tcExtendGlobalValEnv, tcSetEnv, tcEnvIds, + tcLookupGlobal_maybe, tcLookupRecId_maybe ) -import TcKind ( TcKind, kindToTcKind ) -import RnHsSyn ( RenamedHsDecl(..) ) +import RnHsSyn ( RenamedTyClDecl ) import HsCore -import HsDecls ( HsIdInfo(..), HsStrictnessInfo(..) ) import Literal ( Literal(..) ) import CoreSyn -import CoreUtils ( coreExprType ) +import CoreUtils ( exprType ) import CoreUnfold -import MagicUFs ( MagicUnfoldingFun ) -import WwLib ( mkWrapper ) -import PrimOp ( PrimOp(..) ) - -import Id ( GenId, mkImported, mkUserId, addInlinePragma, - isPrimitiveId_maybe, dataConArgTys, Id ) -import Type ( mkSynTy, splitAlgTyConApp ) -import TyVar ( mkSysTyVar ) -import Name ( Name ) -import Unique ( rationalTyConKey, uniqueOf ) -import TysWiredIn ( integerTy ) -import PragmaInfo ( PragmaInfo(..) ) +import CoreLint ( lintUnfolding ) +import WorkWrap ( mkWrapper ) + +import Id ( Id, mkVanillaGlobal, mkLocalId, idName, isDataConWrapId_maybe ) +import Module ( Module ) +import MkId ( mkCCallOpId ) +import IdInfo +import DataCon ( DataCon, dataConId, dataConSig, dataConArgTys ) +import Type ( mkTyVarTys, splitAlgTyConApp_maybe ) +import TysWiredIn ( tupleCon ) +import Var ( mkTyVar, tyVarKind ) +import Name ( Name, nameIsLocalOrFrom ) +import Demand ( wwLazy ) import ErrUtils ( pprBagOfErrors ) -import Maybes ( maybeToBool ) import Outputable import Util ( zipWithEqual ) - -import IdInfo +import HscTypes ( TyThing(..) ) \end{code} Ultimately, type signatures in interfaces will have pragmatic @@ -52,101 +49,126 @@ As always, we do not have to worry about user-pragmas in interface signatures. \begin{code} -tcInterfaceSigs :: TcEnv s -- Envt to use when checking unfoldings - -> [RenamedHsDecl] -- Ignore non-sig-decls in these decls - -> TcM s [Id] +tcInterfaceSigs :: RecTcEnv -- Envt to use when checking unfoldings + -> Module -- This module + -> [RenamedTyClDecl] -- Ignore non-sig-decls in these decls + -> TcM [Id] -tcInterfaceSigs unf_env (SigD (IfaceSig name ty id_infos src_loc) : rest) - = tcAddSrcLoc src_loc ( - tcAddErrCtxt (ifaceSigCtxt name) ( - tcHsType ty `thenTc` \ sigma_ty -> - tcIdInfo unf_env name sigma_ty noIdInfo id_infos `thenTc` \ id_info' -> - let - imp_id = mkImported name sigma_ty id_info' - sig_id | any inline_please id_infos = addInlinePragma imp_id - | otherwise = imp_id - - inline_please (HsUnfold inline _) = inline - inline_please (HsStrictness (HsStrictnessInfo _ (Just _))) = True -- Inline wrappers - inline_please other = False - in - returnTc sig_id - )) `thenTc` \ sig_id -> - tcInterfaceSigs unf_env rest `thenTc` \ sig_ids -> - returnTc (sig_id : sig_ids) - -tcInterfaceSigs unf_env (other_decl : rest) = tcInterfaceSigs unf_env rest - -tcInterfaceSigs unf_env [] = returnTc [] +tcInterfaceSigs unf_env mod decls + = listTc [ do_one name ty id_infos src_loc + | IfaceSig {tcdName = name, tcdType = ty, tcdIdInfo = id_infos, tcdLoc =src_loc} <- decls] + where + in_scope_vars = filter (nameIsLocalOrFrom mod . idName) (tcEnvIds unf_env) + -- Oops: using isLocalId instead can give a black hole + -- because it looks at the idinfo + + -- When we have hi-boot files, an unfolding might refer to + -- something defined in this module, so we must build a + -- suitable in-scope set. This thunk will only be poked + -- if -dcore-lint is on. + + do_one name ty id_infos src_loc + = tcAddSrcLoc src_loc $ + tcAddErrCtxt (ifaceSigCtxt name) $ + tcIfaceType ty `thenTc` \ sigma_ty -> + tcIdInfo unf_env in_scope_vars name + sigma_ty id_infos `thenTc` \ id_info -> + returnTc (mkVanillaGlobal name sigma_ty id_info) \end{code} \begin{code} -tcIdInfo unf_env name ty info info_ins - = go noIdInfo info_ins +tcIdInfo unf_env in_scope_vars name ty info_ins + = foldlTc tcPrag init_info info_ins where - go info_so_far [] = returnTc info_so_far - go info (HsArity arity : rest) = go (info `addArityInfo` arity) rest - go info (HsUpdate upd : rest) = go (info `addUpdateInfo` upd) rest - go info (HsFBType fb : rest) = go (info `addFBTypeInfo` fb) rest - go info (HsArgUsage au : rest) = go (info `addArgUsageInfo` au) rest - - go info (HsUnfold inline expr : rest) = tcUnfolding unf_env name expr `thenNF_Tc` \ unfold_info -> - go (info `addUnfoldInfo` unfold_info) rest - - go info (HsStrictness strict : rest) = tcStrictness unf_env ty info strict `thenTc` \ info' -> - go info' rest + -- set the CgInfo to something sensible but uninformative before + -- we start, because the default CgInfo is a panic. + init_info = vanillaIdInfo `setCgInfo` vanillaCgInfo + + tcPrag info (HsNoCafRefs) = returnTc (info `setCafInfo` NoCafRefs) + tcPrag info HsCprInfo = returnTc (info `setCprInfo` ReturnsCPR) + + tcPrag info (HsArity arity) = + returnTc (info `setArityInfo` (ArityExactly arity) + `setCgArity` arity) + + tcPrag info (HsUnfold inline_prag expr) + = tcPragExpr unf_env name in_scope_vars expr `thenNF_Tc` \ maybe_expr' -> + let + -- maybe_expr doesn't get looked at if the unfolding + -- is never inspected; so the typecheck doesn't even happen + unfold_info = case maybe_expr' of + Nothing -> noUnfolding + Just expr' -> mkTopUnfolding expr' + info1 = info `setUnfoldingInfo` unfold_info + info2 = info1 `setInlinePragInfo` inline_prag + in + returnTc info2 + + tcPrag info (HsStrictness strict_info) + = returnTc (info `setStrictnessInfo` strict_info) + + tcPrag info (HsWorker nm arity) + = tcWorkerInfo unf_env ty info nm arity \end{code} \begin{code} -tcStrictness unf_env ty info (HsStrictnessInfo demands maybe_worker) - = tcWorker unf_env maybe_worker `thenNF_Tc` \ maybe_worker_id -> - uniqSMToTcM (mkWrapper ty demands) `thenNF_Tc` \ wrap_fn -> +tcWorkerInfo unf_env ty info worker_name arity + = uniqSMToTcM (mkWrapper ty arity demands res_bot cpr_info) `thenNF_Tc` \ wrap_fn -> let - -- Watch out! We can't pull on maybe_worker_id too eagerly! - info' = case maybe_worker_id of - Just worker_id -> info `addUnfoldInfo` mkUnfolding NoPragmaInfo (wrap_fn worker_id) - Nothing -> info - has_worker = maybeToBool maybe_worker_id + -- Watch out! We can't pull on unf_env too eagerly! + info' = case tcLookupRecId_maybe unf_env worker_name of + Just worker_id -> + info `setUnfoldingInfo` mkTopUnfolding (wrap_fn worker_id) + `setWorkerInfo` HasWorker worker_id arity + + Nothing -> pprTrace "tcWorkerInfo failed:" + (ppr worker_name) info in - returnTc (info' `addStrictnessInfo` StrictnessInfo demands has_worker) - --- Boring to write these out, but the result type differs from the arg type... -tcStrictness unf_env ty info HsBottom - = returnTc (info `addStrictnessInfo` BottomGuaranteed) -\end{code} - -\begin{code} -tcWorker unf_env Nothing = returnNF_Tc Nothing - -tcWorker unf_env (Just (worker_name,_)) - = returnNF_Tc (trace_maybe maybe_worker_id) + returnTc info' where - maybe_worker_id = tcExplicitLookupGlobal unf_env worker_name - - -- The trace is so we can see what's getting dropped - trace_maybe Nothing = pprTrace "tcWorker failed:" (ppr worker_name) Nothing - trace_maybe (Just x) = Just x + -- We are relying here on cpr and strictness info always appearing + -- before worker info, fingers crossed .... + cpr_info = cprInfo info + + (demands, res_bot) + = case strictnessInfo info of + StrictnessInfo d r -> (d,r) + _ -> (take arity (repeat wwLazy),False) + -- Noncommittal \end{code} For unfoldings we try to do the job lazily, so that we never type check an unfolding that isn't going to be looked at. \begin{code} -tcUnfolding unf_env name core_expr +tcPragExpr unf_env name in_scope_vars expr + = tcDelay unf_env doc $ + tcCoreExpr expr `thenTc` \ core_expr' -> + + -- Check for type consistency in the unfolding + tcGetSrcLoc `thenNF_Tc` \ src_loc -> + getDOptsTc `thenTc` \ dflags -> + case lintUnfolding dflags src_loc in_scope_vars core_expr' of + (Nothing,_) -> returnTc core_expr' -- ignore warnings + (Just fail_msg,_) -> failWithTc ((doc <+> text "failed Lint") $$ fail_msg) + where + doc = text "unfolding of" <+> ppr name + +tcDelay :: RecTcEnv -> SDoc -> TcM a -> NF_TcM (Maybe a) +tcDelay unf_env doc thing_inside = forkNF_Tc ( - recoverNF_Tc no_unfolding ( - tcSetEnv unf_env $ - tcCoreExpr core_expr `thenTc` \ core_expr' -> - returnTc (mkUnfolding NoPragmaInfo core_expr') + recoverNF_Tc bad_value ( + tcSetEnv unf_env thing_inside `thenTc` \ r -> + returnTc (Just r) )) where -- The trace tells what wasn't available, for the benefit of -- compiler hackers who want to improve it! - no_unfolding = getErrsTc `thenNF_Tc` \ (warns,errs) -> - returnNF_Tc (pprTrace "tcUnfolding failed with:" - (hang (ppr name) 4 (pprBagOfErrors errs)) - NoUnfolding) + bad_value = getErrsTc `thenNF_Tc` \ (warns,errs) -> + returnNF_Tc (pprTrace "Failed:" + (hang doc 4 (pprBagOfErrors errs)) + Nothing) \end{code} @@ -156,12 +178,12 @@ Variables in unfoldings ****** Why? Because we know all the types and want to bind them to real Ids. \begin{code} -tcVar :: Name -> TcM s Id +tcVar :: Name -> TcM Id tcVar name - = tcLookupGlobalValueMaybe name `thenNF_Tc` \ maybe_id -> + = tcLookupGlobal_maybe name `thenNF_Tc` \ maybe_id -> case maybe_id of { - Just id -> returnTc id; - Nothing -> failWithTc (noDecl name) + Just (AnId id) -> returnTc id ; + Nothing -> failWithTc (noDecl name) } noDecl name = hsep [ptext SLIT("Warning: no binding for"), ppr name] @@ -170,62 +192,61 @@ noDecl name = hsep [ptext SLIT("Warning: no binding for"), ppr name] UfCore expressions. \begin{code} -tcCoreExpr :: UfExpr Name -> TcM s CoreExpr +tcCoreExpr :: UfExpr Name -> TcM CoreExpr + +tcCoreExpr (UfType ty) + = tcIfaceType ty `thenTc` \ ty' -> + -- It might not be of kind type + returnTc (Type ty') tcCoreExpr (UfVar name) = tcVar name `thenTc` \ id -> returnTc (Var id) --- rationalTy isn't built in so we have to construct it --- (the "ty" part of the incoming literal is simply bottom) -tcCoreExpr (UfLit (NoRepRational lit _)) - = tcLookupTyConByKey rationalTyConKey `thenNF_Tc` \ rational_tycon -> - let - rational_ty = mkSynTy rational_tycon [] - in - returnTc (Lit (NoRepRational lit rational_ty)) +tcCoreExpr (UfLit lit) + = returnTc (Lit lit) --- Similarly for integers, except that it is wired in -tcCoreExpr (UfLit (NoRepInteger lit _)) - = returnTc (Lit (NoRepInteger lit integerTy)) +-- The dreaded lit-lits are also similar, except here the type +-- is read in explicitly rather than being implicit +tcCoreExpr (UfLitLit lit ty) + = tcIfaceType ty `thenTc` \ ty' -> + returnTc (Lit (MachLitLit lit ty')) -tcCoreExpr (UfLit other_lit) - = returnTc (Lit other_lit) +tcCoreExpr (UfCCall cc ty) + = tcIfaceType ty `thenTc` \ ty' -> + tcGetUnique `thenNF_Tc` \ u -> + returnTc (Var (mkCCallOpId u cc ty')) -tcCoreExpr (UfCon con args) - = tcVar con `thenTc` \ con_id -> - mapTc tcCoreArg args `thenTc` \ args' -> - returnTc (Con con_id args') +tcCoreExpr (UfTuple (HsTupCon _ boxity arity) args) + = mapTc tcCoreExpr args `thenTc` \ args' -> + let + -- Put the missing type arguments back in + con_args = map (Type . exprType) args' ++ args' + in + returnTc (mkApps (Var con_id) con_args) + where + con_id = dataConId (tupleCon boxity arity) + -tcCoreExpr (UfPrim prim args) - = tcCorePrim prim `thenTc` \ primop -> - mapTc tcCoreArg args `thenTc` \ args' -> - returnTc (Prim primop args') +tcCoreExpr (UfLam bndr body) + = tcCoreLamBndr bndr $ \ bndr' -> + tcCoreExpr body `thenTc` \ body' -> + returnTc (Lam bndr' body') tcCoreExpr (UfApp fun arg) = tcCoreExpr fun `thenTc` \ fun' -> - tcCoreArg arg `thenTc` \ arg' -> + tcCoreExpr arg `thenTc` \ arg' -> returnTc (App fun' arg') -tcCoreExpr (UfCase scrut alts) - = tcCoreExpr scrut `thenTc` \ scrut' -> - tcCoreAlts (coreExprType scrut') alts `thenTc` \ alts' -> - returnTc (Case scrut' alts') - -tcCoreExpr (UfSCC cc expr) - = tcCoreExpr expr `thenTc` \ expr' -> - returnTc (SCC cc expr') - -tcCoreExpr(UfCoerce coercion ty body) - = tcCoercion coercion `thenTc` \ coercion' -> - tcHsTypeKind ty `thenTc` \ (_,ty') -> - tcCoreExpr body `thenTc` \ body' -> - returnTc (Coerce coercion' ty' body') - -tcCoreExpr (UfLam bndr body) - = tcCoreLamBndr bndr $ \ bndr' -> - tcCoreExpr body `thenTc` \ body' -> - returnTc (Lam bndr' body') +tcCoreExpr (UfCase scrut case_bndr alts) + = tcCoreExpr scrut `thenTc` \ scrut' -> + let + scrut_ty = exprType scrut' + case_bndr' = mkLocalId case_bndr scrut_ty + in + tcExtendGlobalValEnv [case_bndr'] $ + mapTc (tcCoreAlt scrut_ty) alts `thenTc` \ alts' -> + returnTc (Case scrut' case_bndr' alts') tcCoreExpr (UfLet (UfNonRec bndr rhs) body) = tcCoreExpr rhs `thenTc` \ rhs' -> @@ -240,96 +261,117 @@ tcCoreExpr (UfLet (UfRec pairs) body) returnTc (Let (Rec (bndrs' `zip` rhss')) body') where (bndrs, rhss) = unzip pairs + +tcCoreExpr (UfNote note expr) + = tcCoreExpr expr `thenTc` \ expr' -> + case note of + UfCoerce to_ty -> tcIfaceType to_ty `thenTc` \ to_ty' -> + returnTc (Note (Coerce to_ty' + (exprType expr')) expr') + UfInlineCall -> returnTc (Note InlineCall expr') + UfInlineMe -> returnTc (Note InlineMe expr') + UfSCC cc -> returnTc (Note (SCC cc) expr') \end{code} \begin{code} tcCoreLamBndr (UfValBinder name ty) thing_inside - = tcHsType ty `thenTc` \ ty' -> + = tcIfaceType ty `thenTc` \ ty' -> let - id = mkUserId name ty' + id = mkLocalId name ty' in tcExtendGlobalValEnv [id] $ - thing_inside (ValBinder id) + thing_inside id tcCoreLamBndr (UfTyBinder name kind) thing_inside = let - tyvar = mkSysTyVar (uniqueOf name) kind + tyvar = mkTyVar name kind in - tcExtendTyVarEnv [name] [(kindToTcKind kind, tyvar)] $ - thing_inside (TyBinder tyvar) + tcExtendTyVarEnv [tyvar] (thing_inside tyvar) +tcCoreLamBndrs [] thing_inside = thing_inside [] +tcCoreLamBndrs (b:bs) thing_inside + = tcCoreLamBndr b $ \ b' -> + tcCoreLamBndrs bs $ \ bs' -> + thing_inside (b':bs') + tcCoreValBndr (UfValBinder name ty) thing_inside - = tcHsType ty `thenTc` \ ty' -> + = tcIfaceType ty `thenTc` \ ty' -> let - id = mkUserId name ty' + id = mkLocalId name ty' in tcExtendGlobalValEnv [id] $ thing_inside id tcCoreValBndrs bndrs thing_inside -- Expect them all to be ValBinders - = mapTc tcHsType tys `thenTc` \ tys' -> + = mapTc tcIfaceType tys `thenTc` \ tys' -> let - ids = zipWithEqual "tcCoreValBndr" mkUserId names tys' + ids = zipWithEqual "tcCoreValBndr" mkLocalId names tys' in tcExtendGlobalValEnv ids $ thing_inside ids where - names = map (\ (UfValBinder name _) -> name) bndrs - tys = map (\ (UfValBinder _ ty) -> ty) bndrs + names = [name | UfValBinder name _ <- bndrs] + tys = [ty | UfValBinder _ ty <- bndrs] \end{code} \begin{code} -tcCoreArg (UfVarArg v) = tcVar v `thenTc` \ v' -> returnTc (VarArg v') -tcCoreArg (UfTyArg ty) = tcHsTypeKind ty `thenTc` \ (_,ty') -> returnTc (TyArg ty') -tcCoreArg (UfLitArg lit) = returnTc (LitArg lit) - -tcCoreAlts scrut_ty (UfAlgAlts alts deflt) - = mapTc tc_alt alts `thenTc` \ alts' -> - tcCoreDefault scrut_ty deflt `thenTc` \ deflt' -> - returnTc (AlgAlts alts' deflt') - where - tc_alt (con, names, rhs) - = tcVar con `thenTc` \ con' -> - let - arg_tys = dataConArgTys con' inst_tys - (tycon, inst_tys, cons) = splitAlgTyConApp scrut_ty - arg_ids = zipWithEqual "tcCoreAlts" mkUserId names arg_tys - in - tcExtendGlobalValEnv arg_ids $ - tcCoreExpr rhs `thenTc` \ rhs' -> - returnTc (con', arg_ids, rhs') - -tcCoreAlts scrut_ty (UfPrimAlts alts deflt) - = mapTc tc_alt alts `thenTc` \ alts' -> - tcCoreDefault scrut_ty deflt `thenTc` \ deflt' -> - returnTc (PrimAlts alts' deflt') - where - tc_alt (lit, rhs) = tcCoreExpr rhs `thenTc` \ rhs' -> - returnTc (lit, rhs') - -tcCoreDefault scrut_ty UfNoDefault = returnTc NoDefault -tcCoreDefault scrut_ty (UfBindDefault name rhs) - = let - deflt_id = mkUserId name scrut_ty +tcCoreAlt scrut_ty (UfDefault, names, rhs) + = ASSERT( null names ) + tcCoreExpr rhs `thenTc` \ rhs' -> + returnTc (DEFAULT, [], rhs') + +tcCoreAlt scrut_ty (UfLitAlt lit, names, rhs) + = ASSERT( null names ) + tcCoreExpr rhs `thenTc` \ rhs' -> + returnTc (LitAlt lit, [], rhs') + +tcCoreAlt scrut_ty (UfLitLitAlt str ty, names, rhs) + = ASSERT( null names ) + tcCoreExpr rhs `thenTc` \ rhs' -> + tcIfaceType ty `thenTc` \ ty' -> + returnTc (LitAlt (MachLitLit str ty'), [], rhs') + +-- A case alternative is made quite a bit more complicated +-- by the fact that we omit type annotations because we can +-- work them out. True enough, but its not that easy! +tcCoreAlt scrut_ty alt@(con, names, rhs) + = tcConAlt con `thenTc` \ con -> + let + (main_tyvars, _, ex_tyvars, _, _, _) = dataConSig con + + (_, inst_tys, cons) = case splitAlgTyConApp_maybe scrut_ty of + Just stuff -> stuff + Nothing -> pprPanic "tcCoreAlt" (ppr alt) + ex_tyvars' = [mkTyVar name (tyVarKind tv) | (name,tv) <- names `zip` ex_tyvars] + ex_tys' = mkTyVarTys ex_tyvars' + arg_tys = dataConArgTys con (inst_tys ++ ex_tys') + id_names = drop (length ex_tyvars) names + arg_ids +#ifdef DEBUG + | length id_names /= length arg_tys + = pprPanic "tcCoreAlts" (ppr (con, names, rhs) $$ + (ppr main_tyvars <+> ppr ex_tyvars) $$ + ppr arg_tys) + | otherwise +#endif + = zipWithEqual "tcCoreAlts" mkLocalId id_names arg_tys in - tcExtendGlobalValEnv [deflt_id] $ - tcCoreExpr rhs `thenTc` \ rhs' -> - returnTc (BindDefault deflt_id rhs') - - -tcCoercion (UfIn n) = tcVar n `thenTc` \ n' -> returnTc (CoerceIn n') -tcCoercion (UfOut n) = tcVar n `thenTc` \ n' -> returnTc (CoerceOut n') - -tcCorePrim (UfOtherOp op) - = tcVar op `thenTc` \ op_id -> - case isPrimitiveId_maybe op_id of - Just prim_op -> returnTc prim_op - Nothing -> pprPanic "tcCorePrim" (ppr op_id) - -tcCorePrim (UfCCallOp str casm gc arg_tys res_ty) - = mapTc tcHsType arg_tys `thenTc` \ arg_tys' -> - tcHsType res_ty `thenTc` \ res_ty' -> - returnTc (CCallOp str casm gc arg_tys' res_ty') + ASSERT( con `elem` cons && length inst_tys == length main_tyvars ) + tcExtendTyVarEnv ex_tyvars' $ + tcExtendGlobalValEnv arg_ids $ + tcCoreExpr rhs `thenTc` \ rhs' -> + returnTc (DataAlt con, ex_tyvars' ++ arg_ids, rhs') + + +tcConAlt :: UfConAlt Name -> TcM DataCon +tcConAlt (UfTupleAlt (HsTupCon _ boxity arity)) + = returnTc (tupleCon boxity arity) + +tcConAlt (UfDataAlt con_name) + = tcVar con_name `thenTc` \ con_id -> + returnTc (case isDataConWrapId_maybe con_id of + Just con -> con + Nothing -> pprPanic "tcCoreAlt" (ppr con_id)) \end{code} \begin{code}