X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Ftypecheck%2FTcSplice.lhs;h=e03993aab32ae5b16594b3ad3cce9b26e37930c8;hp=f65dc29ad73fabf15d7f59613ce19cb6ead5fb6a;hb=1e50fd4185479a62e02d987bdfcb1c62712859ca;hpb=aa9a4f1053d3c554629a2ec25955e7530c95b892 diff --git a/compiler/typecheck/TcSplice.lhs b/compiler/typecheck/TcSplice.lhs index f65dc29..e03993a 100644 --- a/compiler/typecheck/TcSplice.lhs +++ b/compiler/typecheck/TcSplice.lhs @@ -13,8 +13,9 @@ TcSplice: Template Haskell splices -- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings -- for details -module TcSplice( tcSpliceExpr, tcSpliceDecls, tcBracket, - runQuasiQuoteExpr, runQuasiQuotePat ) where +module TcSplice( kcSpliceType, tcSpliceExpr, tcSpliceDecls, tcBracket, + lookupThName_maybe, + runQuasiQuoteExpr, runQuasiQuotePat, runAnnotation ) where #include "HsVersions.h" @@ -41,12 +42,15 @@ import TcIface import TypeRep import Name import NameEnv +import PrelNames import HscTypes import OccName import Var import Module +import Annotations import TcRnMonad import Class +import Inst import TyCon import DataCon import Id @@ -55,21 +59,28 @@ import TysWiredIn import DsMeta import DsExpr import DsMonad hiding (Splice) +import Serialized import ErrUtils import SrcLoc import Outputable import Unique -import Maybe +import Data.Maybe import BasicTypes import Panic import FastString +import Exception import qualified Language.Haskell.TH as TH -- THSyntax gives access to internal functions and data types import qualified Language.Haskell.TH.Syntax as TH +#ifdef GHCI +-- Because GHC.Desugar might not be in the base library of the bootstrapping compiler +import GHC.Desugar ( AnnotationWrapper(..) ) +#endif + import GHC.Exts ( unsafeCoerce#, Int#, Int(..) ) -import qualified Exception ( userErrors ) +import System.IO.Error \end{code} Note [Template Haskell levels] @@ -163,8 +174,11 @@ tcSpliceExpr :: HsSplice Name -> BoxyRhoType -> TcM (HsExpr TcId) kcSpliceType :: HsSplice Name -> TcM (HsType Name, TcKind) -- None of these functions add constraints to the LIE +lookupThName_maybe :: TH.Name -> TcM (Maybe Name) + runQuasiQuoteExpr :: HsQuasiQuote Name -> TcM (LHsExpr RdrName) runQuasiQuotePat :: HsQuasiQuote Name -> TcM (LPat RdrName) +runAnnotation :: CoreAnnTarget -> LHsExpr Name -> TcM Annotation #ifndef GHCI tcBracket x _ = pprPanic "Cant do tcBracket without GHCi" (ppr x) @@ -172,8 +186,11 @@ tcSpliceExpr e = pprPanic "Cant do tcSpliceExpr without GHCi" (ppr e) tcSpliceDecls x = pprPanic "Cant do tcSpliceDecls without GHCi" (ppr x) kcSpliceType x = pprPanic "Cant do kcSpliceType without GHCi" (ppr x) +lookupThName_maybe n = pprPanic "Cant do lookupThName_maybe without GHCi" (ppr n) + runQuasiQuoteExpr q = pprPanic "Cant do runQuasiQuoteExpr without GHCi" (ppr q) runQuasiQuotePat q = pprPanic "Cant do runQuasiQuotePat without GHCi" (ppr q) +runAnnotation _ q = pprPanic "Cant do runAnnotation without GHCi" (ppr q) #else \end{code} @@ -196,30 +213,31 @@ Desugared: f = do { s7 <- g Int 3 ; return (ConE "Data.Maybe.Just" s7) } \begin{code} -tcBracket brack res_ty = do - level <- getStage - case bracketOK level of { - Nothing -> failWithTc (illegalBracket level) ; - Just next_level -> do +tcBracket brack res_ty + = addErrCtxt (hang (ptext (sLit "In the Template Haskell quotation")) + 2 (ppr brack)) $ + do { level <- getStage + ; case bracketOK level of { + Nothing -> failWithTc (illegalBracket level) ; + Just next_level -> do { -- Typecheck expr to make sure it is valid, -- but throw away the results. We'll type check -- it again when we actually use it. - recordThUse - pending_splices <- newMutVar [] - lie_var <- getLIEVar + recordThUse + ; pending_splices <- newMutVar [] + ; lie_var <- getLIEVar - (meta_ty, lie) <- setStage (Brack next_level pending_splices lie_var) - (getLIE (tc_bracket next_level brack)) - tcSimplifyBracket lie + ; (meta_ty, lie) <- setStage (Brack next_level pending_splices lie_var) + (getLIE (tc_bracket next_level brack)) + ; tcSimplifyBracket lie -- Make the expected type have the right shape - boxyUnify meta_ty res_ty + ; _ <- boxyUnify meta_ty res_ty -- Return the original expression, not the type-decorated one - pendings <- readMutVar pending_splices - return (noLoc (HsBracketOut brack pendings)) - } + ; pendings <- readMutVar pending_splices + ; return (noLoc (HsBracketOut brack pendings)) }}} tc_bracket :: ThLevel -> HsBracket Name -> TcM TcType tc_bracket use_lvl (VarBr name) -- Note [Quoting names] @@ -239,17 +257,17 @@ tc_bracket use_lvl (VarBr name) -- Note [Quoting names] tc_bracket _ (ExpBr expr) = do { any_ty <- newFlexiTyVarTy liftedTypeKind - ; tcMonoExpr expr any_ty + ; _ <- tcMonoExprNC expr any_ty -- NC for no context; tcBracket does that ; tcMetaTy expQTyConName } -- Result type is Expr (= Q Exp) tc_bracket _ (TypBr typ) - = do { tcHsSigType ExprSigCtxt typ + = do { _ <- tcHsSigTypeNC ThBrackCtxt typ ; tcMetaTy typeQTyConName } -- Result type is Type (= Q Typ) tc_bracket _ (DecBr decls) - = do { tcTopSrcDecls emptyModDetails decls + = do { _ <- tcTopSrcDecls emptyModDetails decls -- Typecheck the declarations, dicarding the result -- We'll get all that stuff later, when we splice it in @@ -284,7 +302,7 @@ tcSpliceExpr (HsSplice name expr) res_ty Just next_level -> case level of { - Comp -> do { e <- tcTopSplice expr res_ty + Comp _ -> do { e <- tcTopSplice expr res_ty ; return (unLoc e) } ; Brack _ ps_var lie_var -> do @@ -294,7 +312,7 @@ tcSpliceExpr (HsSplice name expr) res_ty -- Here (h 4) :: Q Exp -- but $(h 4) :: forall a.a i.e. anything! - unBox res_ty + _ <- unBox res_ty meta_exp_ty <- tcMetaTy expQTyConName expr' <- setStage (Splice next_level) ( setLIEVar lie_var $ @@ -330,8 +348,7 @@ tcTopSplice expr res_ty = do traceTc (text "Got result" <+> ppr expr2) - showSplice "expression" - zonked_q_expr (ppr expr2) + showSplice "expression" expr (ppr expr2) -- Rename it, but bale out if there are errors -- otherwise the type checker just gives more spurious errors @@ -343,23 +360,73 @@ tcTopSplice expr res_ty = do tcTopSpliceExpr :: LHsExpr Name -> TcType -> TcM (LHsExpr Id) -- Type check an expression that is the body of a top-level splice -- (the caller will compile and run it) -tcTopSpliceExpr expr meta_ty - = checkNoErrs $ -- checkNoErrs: must not try to run the thing - -- if the type checker fails! +tcTopSpliceExpr expr meta_ty + = checkNoErrs $ -- checkNoErrs: must not try to run the thing + -- if the type checker fails! + do { (expr', const_binds) <- tcSimplifyStagedExpr topSpliceStage $ + (recordThUse >> tcMonoExpr expr meta_ty) + -- Zonk it and tie the knot of dictionary bindings + ; zonkTopLExpr (mkHsDictLet const_binds expr') } +\end{code} - setStage topSpliceStage $ do - - do { recordThUse -- Record that TH is used (for pkg depdendency) +%************************************************************************ +%* * + Annotations +%* * +%************************************************************************ - -- Typecheck the expression - ; (expr', lie) <- getLIE (tcMonoExpr expr meta_ty) - - -- Solve the constraints - ; const_binds <- tcSimplifyTop lie - - -- And zonk it - ; zonkTopLExpr (mkHsDictLet const_binds expr') } +\begin{code} +runAnnotation target expr = do + expr_ty <- newFlexiTyVarTy liftedTypeKind + + -- Find the classes we want instances for in order to call toAnnotationWrapper + data_class <- tcLookupClass dataClassName + + -- Check the instances we require live in another module (we want to execute it..) + -- and check identifiers live in other modules using TH stage checks. tcSimplifyStagedExpr + -- also resolves the LIE constraints to detect e.g. instance ambiguity + ((wrapper, expr'), const_binds) <- tcSimplifyStagedExpr topAnnStage $ do + expr' <- tcPolyExprNC expr expr_ty + -- By instantiating the call >here< it gets registered in the + -- LIE consulted by tcSimplifyStagedExpr + -- and hence ensures the appropriate dictionary is bound by const_binds + wrapper <- instCall AnnOrigin [expr_ty] [mkClassPred data_class [expr_ty]] + return (wrapper, expr') + + -- We manually wrap the typechecked expression in a call to toAnnotationWrapper + loc <- getSrcSpanM + to_annotation_wrapper_id <- tcLookupId toAnnotationWrapperName + let specialised_to_annotation_wrapper_expr = L loc (HsWrap wrapper (HsVar to_annotation_wrapper_id)) + wrapped_expr' = mkHsDictLet const_binds $ + L loc (HsApp specialised_to_annotation_wrapper_expr expr') + + -- If we have type checking problems then potentially zonking + -- (and certainly compilation) may fail. Give up NOW! + failIfErrsM + + -- Zonk the type variables out of that raw expression. Note that + -- in particular we don't call recordThUse, since we don't + -- necessarily use any code or definitions from that package. + zonked_wrapped_expr' <- zonkTopLExpr wrapped_expr' + + -- Run the appropriately wrapped expression to get the value of + -- the annotation and its dictionaries. The return value is of + -- type AnnotationWrapper by construction, so this conversion is + -- safe + flip runMetaAW zonked_wrapped_expr' $ \annotation_wrapper -> + case annotation_wrapper of + AnnotationWrapper value | let serialized = toSerialized serializeWithData value -> + -- Got the value and dictionaries: build the serialized value and + -- call it a day. We ensure that we seq the entire serialized value + -- in order that any errors in the user-written code for the + -- annotation are exposed at this point. This is also why we are + -- doing all this stuff inside the context of runMeta: it has the + -- facilities to deal with user error in a meta-level expression + seqSerialized serialized `seq` Annotation { + ann_target = target, + ann_value = serialized + } \end{code} @@ -419,9 +486,9 @@ runQuasiQuote (HsQuasiQuote _name quoter q_span quote) quote_selector desc meta_ -- Run the expression ; traceTc (text "About to run" <+> ppr zonked_q_expr) - ; result <- runMeta convert zonked_q_expr + ; result <- runMetaQ convert zonked_q_expr ; traceTc (text "Got result" <+> ppr result) - ; showSplice desc zonked_q_expr (ppr result) + ; showSplice desc quoteExpr (ppr result) ; return result } @@ -455,7 +522,7 @@ kcSpliceType (HsSplice name hs_expr) Just next_level -> do { case level of { - Comp -> do { (t,k) <- kcTopSpliceType hs_expr + Comp _ -> do { (t,k) <- kcTopSpliceType hs_expr ; return (unLoc t, k) } ; Brack _ ps_var lie_var -> do @@ -491,14 +558,14 @@ kcTopSpliceType expr ; traceTc (text "Got result" <+> ppr hs_ty2) - ; showSplice "type" zonked_q_expr (ppr hs_ty2) + ; showSplice "type" expr (ppr hs_ty2) -- Rename it, but bale out if there are errors -- otherwise the type checker just gives more spurious errors ; let doc = ptext (sLit "In the spliced type") <+> ppr hs_ty2 ; hs_ty3 <- checkNoErrs (rnLHsType doc hs_ty2) - ; kcHsType hs_ty3 } + ; kcLHsType hs_ty3 } \end{code} %************************************************************************ @@ -523,7 +590,7 @@ tcSpliceDecls expr ; traceTc (text "Got result" <+> vcat (map ppr decls)) ; showSplice "declarations" - zonked_q_expr + expr (ppr (getLoc expr) $$ (vcat (map ppr decls))) ; return decls } \end{code} @@ -536,30 +603,49 @@ tcSpliceDecls expr %************************************************************************ \begin{code} +runMetaAW :: (AnnotationWrapper -> output) + -> LHsExpr Id -- Of type AnnotationWrapper + -> TcM output +runMetaAW k = runMeta False (\_ -> return . Right . k) + -- We turn off showing the code in meta-level exceptions because doing so exposes + -- the toAnnotationWrapper function that we slap around the users code + +runQThen :: (SrcSpan -> input -> Either Message output) + -> SrcSpan + -> TH.Q input + -> TcM (Either Message output) +runQThen f expr_span what = TH.runQ what >>= (return . f expr_span) + +runMetaQ :: (SrcSpan -> input -> Either Message output) + -> LHsExpr Id + -> TcM output +runMetaQ = runMeta True . runQThen + runMetaE :: (SrcSpan -> TH.Exp -> Either Message (LHsExpr RdrName)) -> LHsExpr Id -- Of type (Q Exp) -> TcM (LHsExpr RdrName) -runMetaE = runMeta +runMetaE = runMetaQ runMetaP :: (SrcSpan -> TH.Pat -> Either Message (Pat RdrName)) -> LHsExpr Id -- Of type (Q Pat) -> TcM (Pat RdrName) -runMetaP = runMeta +runMetaP = runMetaQ runMetaT :: (SrcSpan -> TH.Type -> Either Message (LHsType RdrName)) -> LHsExpr Id -- Of type (Q Type) -> TcM (LHsType RdrName) -runMetaT = runMeta +runMetaT = runMetaQ runMetaD :: (SrcSpan -> [TH.Dec] -> Either Message [LHsDecl RdrName]) -> LHsExpr Id -- Of type Q [Dec] -> TcM [LHsDecl RdrName] -runMetaD = runMeta +runMetaD = runMetaQ -runMeta :: (SrcSpan -> th_syn -> Either Message hs_syn) +runMeta :: Bool -- Whether code should be printed in the exception message + -> (SrcSpan -> input -> TcM (Either Message output)) -> LHsExpr Id -- Of type X - -> TcM hs_syn -- Of type t -runMeta convert expr + -> TcM output -- Of type t +runMeta show_code run_and_convert expr = do { -- Desugar ds_expr <- initDsTc (dsLExpr expr) -- Compile and link it; might fail if linking fails @@ -586,22 +672,23 @@ runMeta convert expr ; either_tval <- tryAllM $ setSrcSpan expr_span $ -- Set the span so that qLocation can -- see where this splice is - do { th_syn <- TH.runQ (unsafeCoerce# hval) - ; case convert expr_span th_syn of + do { mb_result <- run_and_convert expr_span (unsafeCoerce# hval) + ; case mb_result of Left err -> failWithTc err - Right hs_syn -> return hs_syn } + Right result -> return $! result } ; case either_tval of Right v -> return v - Left exn | Just s <- Exception.userErrors exn - , s == "IOEnv failure" - -> failM -- Error already in Tc monad - | otherwise -> failWithTc (mk_msg "run" exn) -- Exception + Left se -> + case fromException se of + Just IOEnvFailure -> + failM -- Error already in Tc monad + _ -> failWithTc (mk_msg "run" se) -- Exception }}} where mk_msg s exn = vcat [text "Exception when trying to" <+> text s <+> text "compile-time code:", nest 2 (text (Panic.showException exn)), - nest 2 (text "Code:" <+> ppr expr)] + if show_code then nest 2 (text "Code:" <+> ppr expr) else empty] \end{code} Note [Exceptions in TH] @@ -625,11 +712,10 @@ like that. Here's how it's processed: * The TcM monad is an instance of Quasi (see TcSplice), and it implements (qReport True s) by using addErr to add an error message to the bag of errors. - The 'fail' in TcM raises a UserError, with the uninteresting string - "IOEnv failure" + The 'fail' in TcM raises an IOEnvFailure exception * So, when running a splice, we catch all exceptions; then for - - a UserError "IOEnv failure", we assume the error is already + - an IOEnvFailure exception, we assume the error is already in the error-bag (above) - other errors, we add an error to the bag and then fail @@ -677,13 +763,18 @@ instance TH.Quasi (IOEnv (Env TcGblEnv TcLclEnv)) where %************************************************************************ \begin{code} -showSplice :: String -> LHsExpr Id -> SDoc -> TcM () -showSplice what before after = do - loc <- getSrcSpanM - traceSplice (vcat [ppr loc <> colon <+> text "Splicing" <+> text what, - nest 2 (sep [nest 2 (ppr before), - text "======>", - nest 2 after])]) +showSplice :: String -> LHsExpr Name -> SDoc -> TcM () +-- Note that 'before' is *renamed* but not *typechecked* +-- Reason (a) less typechecking crap +-- (b) data constructors after type checking have been +-- changed to their *wrappers*, and that makes them +-- print always fully qualified +showSplice what before after + = do { loc <- getSrcSpanM + ; traceSplice (vcat [ppr loc <> colon <+> text "Splicing" <+> text what, + nest 2 (sep [nest 2 (ppr before), + text "======>", + nest 2 after])]) } illegalBracket :: ThStage -> SDoc illegalBracket level @@ -721,14 +812,17 @@ reify th_name ppr_ns _ = panic "reify/ppr_ns" lookupThName :: TH.Name -> TcM Name -lookupThName th_name@(TH.Name occ flavour) - = do { mb_ns <- mapM lookup [ thRdrName gns occ_str flavour - | gns <- guessed_nss] - ; case catMaybes mb_ns of - [] -> failWithTc (notInScope th_name) - (n:_) -> return n } -- Pick the first that works - -- E.g. reify (mkName "A") will pick the class A - -- in preference to the data constructor A +lookupThName th_name = do + mb_name <- lookupThName_maybe th_name + case mb_name of + Nothing -> failWithTc (notInScope th_name) + Just name -> return name + +lookupThName_maybe th_name + = do { names <- mapMaybeM lookup (thRdrNameGuesses th_name) + -- Pick the first that works + -- E.g. reify (mkName "A") will pick the class A in preference to the data constructor A + ; return (listToMaybe names) } where lookup rdr_name = do { -- Repeat much of lookupOccRn, becase we want @@ -736,16 +830,7 @@ lookupThName th_name@(TH.Name occ flavour) ; rdr_env <- getLocalRdrEnv ; case lookupLocalRdrEnv rdr_env rdr_name of Just name -> return (Just name) - Nothing | not (isSrcRdrName rdr_name) -- Exact, Orig - -> do { name <- lookupImportedName rdr_name - ; return (Just name) } - | otherwise -- Unqual, Qual - -> lookupSrcOcc_maybe rdr_name } - - -- guessed_ns are the name spaces guessed from looking at the TH name - guessed_nss | isLexCon (mkFastString occ_str) = [OccName.tcName, OccName.dataName] - | otherwise = [OccName.varName, OccName.tvName] - occ_str = TH.occString occ + Nothing -> lookupGlobalOccRn_maybe rdr_name } tcLookupTh :: Name -> TcM TcTyThing -- This is a specialised version of TcEnv.tcLookup; specialised mainly in that @@ -792,7 +877,7 @@ reifyThing (AGlobal (AnId id)) = do { ty <- reifyType (idType id) ; fix <- reifyFixity (idName id) ; let v = reifyName id - ; case globalIdDetails id of + ; case idDetails id of ClassOpId cls -> return (TH.ClassOpI v ty (reifyName cls) fix) _ -> return (TH.VarI v ty Nothing fix) } @@ -803,7 +888,9 @@ reifyThing (AGlobal (ADataCon dc)) = do { let name = dataConName dc ; ty <- reifyType (idType (dataConWrapId dc)) ; fix <- reifyFixity name - ; return (TH.DataConI (reifyName name) ty (reifyName (dataConTyCon dc)) fix) } + ; return (TH.DataConI (reifyName name) ty + (reifyName (dataConOrigTyCon dc)) fix) + } reifyThing (ATcId {tct_id = id, tct_type = ty}) = do { ty1 <- zonkTcType ty -- Make use of all the info we have, even @@ -822,13 +909,26 @@ reifyThing (AThing {}) = panic "reifyThing AThing" ------------------------------ reifyTyCon :: TyCon -> TcM TH.Info reifyTyCon tc - | isFunTyCon tc = return (TH.PrimTyConI (reifyName tc) 2 False) - | isPrimTyCon tc = return (TH.PrimTyConI (reifyName tc) (tyConArity tc) (isUnLiftedTyCon tc)) + | isFunTyCon tc + = return (TH.PrimTyConI (reifyName tc) 2 False) + | isPrimTyCon tc + = return (TH.PrimTyConI (reifyName tc) (tyConArity tc) (isUnLiftedTyCon tc)) + | isOpenTyCon tc + = let flavour = reifyFamFlavour tc + tvs = tyConTyVars tc + kind = tyConKind tc + kind' + | isLiftedTypeKind kind = Nothing + | otherwise = Just $ reifyKind kind + in + return (TH.TyConI $ + TH.FamilyD flavour (reifyName tc) (reifyTyVars tvs) kind') | isSynTyCon tc = do { let (tvs, rhs) = synTyConDefn tc ; rhs' <- reifyType rhs ; return (TH.TyConI $ - TH.TySynD (reifyName tc) (reifyTyVars tvs) rhs') } + TH.TySynD (reifyName tc) (reifyTyVars tvs) rhs') + } reifyTyCon tc = do { cxt <- reifyCxt (tyConStupidTheta tc) @@ -838,7 +938,7 @@ reifyTyCon tc r_tvs = reifyTyVars tvs deriv = [] -- Don't know about deriving decl | isNewTyCon tc = TH.NewtypeD cxt name r_tvs (head cons) deriv - | otherwise = TH.DataD cxt name r_tvs cons deriv + | otherwise = TH.DataD cxt name r_tvs cons deriv ; return (TH.TyConI decl) } reifyDataCon :: [Type] -> DataCon -> TcM TH.Con @@ -860,7 +960,7 @@ reifyDataCon tys dc else return (TH.NormalC name (stricts `zip` arg_tys)) } | otherwise - = failWithTc (ptext (sLit "Can't reify a non-Haskell-98 data constructor:") + = failWithTc (ptext (sLit "Can't reify a GADT data constructor:") <+> quotes (ppr dc)) ------------------------------ @@ -890,23 +990,55 @@ reifyType (PredTy {}) = panic "reifyType PredTy" reifyTypes :: [Type] -> TcM [TH.Type] reifyTypes = mapM reifyType -reifyCxt :: [PredType] -> TcM [TH.Type] + +reifyKind :: Kind -> TH.Kind +reifyKind ki + = let (kis, ki') = splitKindFunTys ki + kis_rep = map reifyKind kis + ki'_rep = reifyNonArrowKind ki' + in + foldl TH.ArrowK ki'_rep kis_rep + where + reifyNonArrowKind k | isLiftedTypeKind k = TH.StarK + | otherwise = pprPanic "Exotic form of kind" + (ppr k) + +reifyCxt :: [PredType] -> TcM [TH.Pred] reifyCxt = mapM reifyPred reifyFunDep :: ([TyVar], [TyVar]) -> TH.FunDep reifyFunDep (xs, ys) = TH.FunDep (map reifyName xs) (map reifyName ys) -reifyTyVars :: [TyVar] -> [TH.Name] -reifyTyVars = map reifyName +reifyFamFlavour :: TyCon -> TH.FamFlavour +reifyFamFlavour tc | isOpenSynTyCon tc = TH.TypeFam + | isOpenTyCon tc = TH.DataFam + | otherwise + = panic "TcSplice.reifyFamFlavour: not a type family" + +reifyTyVars :: [TyVar] -> [TH.TyVarBndr] +reifyTyVars = map reifyTyVar + where + reifyTyVar tv | isLiftedTypeKind kind = TH.PlainTV name + | otherwise = TH.KindedTV name (reifyKind kind) + where + kind = tyVarKind tv + name = reifyName tv reify_tc_app :: TH.Name -> [TypeRep.Type] -> TcM TH.Type reify_tc_app tc tys = do { tys' <- reifyTypes tys ; return (foldl TH.AppT (TH.ConT tc) tys') } -reifyPred :: TypeRep.PredType -> TcM TH.Type -reifyPred (ClassP cls tys) = reify_tc_app (reifyName cls) tys +reifyPred :: TypeRep.PredType -> TcM TH.Pred +reifyPred (ClassP cls tys) + = do { tys' <- reifyTypes tys + ; return $ TH.ClassP (reifyName cls) tys' + } reifyPred p@(IParam _ _) = noTH (sLit "implicit parameters") (ppr p) -reifyPred (EqPred {}) = panic "reifyPred EqPred" +reifyPred (EqPred ty1 ty2) + = do { ty1' <- reifyType ty1 + ; ty2' <- reifyType ty2 + ; return $ TH.EqualP ty1' ty2' + } ------------------------------ @@ -920,7 +1052,7 @@ reifyName thing -- have free variables, we may need to generate NameL's for them. where name = getName thing - mod = nameModule name + mod = ASSERT( isExternalName name ) nameModule name pkg_str = packageIdString (modulePackageId mod) mod_str = moduleNameString (moduleName mod) occ_str = occNameString occ