X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FhsSyn%2FConvert.lhs;h=492f2552cdb5a9074430ec235e2ffaf10b3df7ba;hp=b48d361ad603aefa344235f765e16cb1947bb3d7;hb=6ddfe9b18d4d280676aab2fa797ddbe6f8a09d6b;hpb=5e5a08eb37f5513cecb47101a97fdaf09c4be040 diff --git a/compiler/hsSyn/Convert.lhs b/compiler/hsSyn/Convert.lhs index b48d361..492f255 100644 --- a/compiler/hsSyn/Convert.lhs +++ b/compiler/hsSyn/Convert.lhs @@ -7,7 +7,8 @@ This module converts Template Haskell syntax into HsSyn \begin{code} module Convert( convertToHsExpr, convertToPat, convertToHsDecls, - convertToHsType, thRdrNameGuesses ) where + convertToHsType, convertToHsPred, + thRdrNameGuesses ) where import HsSyn as Hs import qualified Class @@ -19,18 +20,20 @@ import qualified OccName import OccName import SrcLoc import Type +import Coercion import TysWiredIn -import BasicTypes +import BasicTypes as Hs import ForeignCall -import Char -import List import Unique import MonadUtils import ErrUtils import Bag +import Util import FastString import Outputable +import Control.Monad( unless ) + import Language.Haskell.TH as TH hiding (sigP) import Language.Haskell.TH.Syntax as TH @@ -40,25 +43,25 @@ import GHC.Exts -- The external interface convertToHsDecls :: SrcSpan -> [TH.Dec] -> Either Message [LHsDecl RdrName] -convertToHsDecls loc ds = initCvt loc (mapM cvtTop ds) +convertToHsDecls loc ds = initCvt loc (mapM cvt_dec ds) + where + cvt_dec d = wrapMsg "declaration" d (cvtDec d) convertToHsExpr :: SrcSpan -> TH.Exp -> Either Message (LHsExpr RdrName) convertToHsExpr loc e - = case initCvt loc (cvtl e) of - Left msg -> Left (msg $$ (ptext (sLit "When splicing TH expression:") - <+> text (show e))) - Right res -> Right res + = initCvt loc $ wrapMsg "expression" e $ cvtl e convertToPat :: SrcSpan -> TH.Pat -> Either Message (LPat RdrName) -convertToPat loc e - = case initCvt loc (cvtPat e) of - Left msg -> Left (msg $$ (ptext (sLit "When splicing TH pattern:") - <+> text (show e))) - Right res -> Right res +convertToPat loc p + = initCvt loc $ wrapMsg "pattern" p $ cvtPat p convertToHsType :: SrcSpan -> TH.Type -> Either Message (LHsType RdrName) -convertToHsType loc t = initCvt loc (cvtType t) +convertToHsType loc t + = initCvt loc $ wrapMsg "type" t $ cvtType t +convertToHsPred :: SrcSpan -> TH.Pred -> Either Message (LHsPred RdrName) +convertToHsPred loc t + = initCvt loc $ wrapMsg "type" t $ cvtPred t ------------------------------------------------------------------- newtype CvtM a = CvtM { unCvtM :: SrcSpan -> Either Message a } @@ -83,132 +86,167 @@ instance Monad CvtM where initCvt :: SrcSpan -> CvtM a -> Either Message a initCvt loc (CvtM m) = m loc -force :: a -> CvtM a -force a = a `seq` return a +force :: a -> CvtM () +force a = a `seq` return () failWith :: Message -> CvtM a -failWith m = CvtM (\_ -> Left full_msg) - where - full_msg = m $$ ptext (sLit "When splicing generated code into the program") +failWith m = CvtM (\_ -> Left m) returnL :: a -> CvtM (Located a) returnL x = CvtM (\loc -> Right (L loc x)) +wrapMsg :: (Show a, TH.Ppr a) => String -> a -> CvtM b -> CvtM b +-- E.g wrapMsg "declaration" dec thing +wrapMsg what item (CvtM m) + = CvtM (\loc -> case m loc of + Left err -> Left (err $$ getPprStyle msg) + Right v -> Right v) + where + -- Show the item in pretty syntax normally, + -- but with all its constructors if you say -dppr-debug + msg sty = hang (ptext (sLit "When splicing a TH") <+> text what <> colon) + 2 (if debugStyle sty + then text (show item) + else text (pprint item)) + wrapL :: CvtM a -> CvtM (Located a) wrapL (CvtM m) = CvtM (\loc -> case m loc of Left err -> Left err Right v -> Right (L loc v)) ------------------------------------------------------------------- -cvtTop :: TH.Dec -> CvtM (LHsDecl RdrName) -cvtTop d@(TH.ValD _ _ _) - = do { L loc d' <- cvtBind d - ; return (L loc $ Hs.ValD d') } +cvtDec :: TH.Dec -> CvtM (LHsDecl RdrName) +cvtDec (TH.ValD pat body ds) + | TH.VarP s <- pat + = do { s' <- vNameL s + ; cl' <- cvtClause (Clause [] body ds) + ; returnL $ Hs.ValD $ mkFunBind s' [cl'] } -cvtTop d@(TH.FunD _ _) - = do { L loc d' <- cvtBind d - ; return (L loc $ Hs.ValD d') } + | otherwise + = do { pat' <- cvtPat pat + ; body' <- cvtGuard body + ; ds' <- cvtLocalDecs (ptext (sLit "a where clause")) ds + ; returnL $ Hs.ValD $ + PatBind { pat_lhs = pat', pat_rhs = GRHSs body' ds' + , pat_rhs_ty = void, bind_fvs = placeHolderNames } } + +cvtDec (TH.FunD nm cls) + | null cls + = failWith (ptext (sLit "Function binding for") + <+> quotes (text (TH.pprint nm)) + <+> ptext (sLit "has no equations")) + | otherwise + = do { nm' <- vNameL nm + ; cls' <- mapM cvtClause cls + ; returnL $ Hs.ValD $ mkFunBind nm' cls' } -cvtTop (TH.SigD nm typ) +cvtDec (TH.SigD nm typ) = do { nm' <- vNameL nm ; ty' <- cvtType typ ; returnL $ Hs.SigD (TypeSig nm' ty') } -cvtTop (TySynD tc tvs rhs) - = do { (_, tc', tvs', _) <- cvt_tycl_hdr [] tc tvs +cvtDec (PragmaD prag) + = do { prag' <- cvtPragmaD prag + ; returnL $ Hs.SigD prag' } + +cvtDec (TySynD tc tvs rhs) + = do { (_, tc', tvs') <- cvt_tycl_hdr [] tc tvs ; rhs' <- cvtType rhs ; returnL $ TyClD (TySynonym tc' tvs' Nothing rhs') } -cvtTop (DataD ctxt tc tvs constrs derivs) - = do { stuff <- cvt_tycl_hdr ctxt tc tvs +cvtDec (DataD ctxt tc tvs constrs derivs) + = do { (ctxt', tc', tvs') <- cvt_tycl_hdr ctxt tc tvs ; cons' <- mapM cvtConstr constrs ; derivs' <- cvtDerivs derivs - ; returnL $ TyClD (mkTyData DataType stuff Nothing cons' derivs') } + ; returnL $ TyClD (TyData { tcdND = DataType, tcdLName = tc', tcdCtxt = ctxt' + , tcdTyVars = tvs', tcdTyPats = Nothing, tcdKindSig = Nothing + , tcdCons = cons', tcdDerivs = derivs' }) } -cvtTop (NewtypeD ctxt tc tvs constr derivs) - = do { stuff <- cvt_tycl_hdr ctxt tc tvs +cvtDec (NewtypeD ctxt tc tvs constr derivs) + = do { (ctxt', tc', tvs') <- cvt_tycl_hdr ctxt tc tvs ; con' <- cvtConstr constr ; derivs' <- cvtDerivs derivs - ; returnL $ TyClD (mkTyData NewType stuff Nothing [con'] derivs') } + ; returnL $ TyClD (TyData { tcdND = NewType, tcdLName = tc', tcdCtxt = ctxt' + , tcdTyVars = tvs', tcdTyPats = Nothing, tcdKindSig = Nothing + , tcdCons = [con'], tcdDerivs = derivs'}) } -cvtTop (ClassD ctxt cl tvs fds decs) - = do { (cxt', tc', tvs', _) <- cvt_tycl_hdr ctxt cl tvs +cvtDec (ClassD ctxt cl tvs fds decs) + = do { (cxt', tc', tvs') <- cvt_tycl_hdr ctxt cl tvs ; fds' <- mapM cvt_fundep fds - ; let (ats, bind_sig_decs) = partition isFamilyD decs - ; (binds', sigs') <- cvtBindsAndSigs bind_sig_decs - ; ats' <- mapM cvtTop ats - ; let ats'' = map unTyClD ats' + ; (binds', sigs', ats') <- cvt_ci_decs (ptext (sLit "a class declaration")) decs ; returnL $ - TyClD $ mkClassDecl (cxt', tc', tvs') fds' sigs' binds' ats'' [] - -- no docs in TH ^^ - } - where - isFamilyD (FamilyD _ _ _) = True - isFamilyD _ = False - -cvtTop (InstanceD tys ty decs) - = do { let (ats, bind_sig_decs) = partition isFamInstD decs - ; (binds', sigs') <- cvtBindsAndSigs bind_sig_decs - ; ats' <- mapM cvtTop ats - ; let ats'' = map unTyClD ats' - ; ctxt' <- cvtContext tys - ; L loc pred' <- cvtPred ty - ; inst_ty' <- returnL $ - mkImplicitHsForAllTy ctxt' (L loc (HsPredTy pred')) - ; returnL $ InstD (InstDecl inst_ty' binds' sigs' ats'') + TyClD $ ClassDecl { tcdCtxt = cxt', tcdLName = tc', tcdTyVars = tvs' + , tcdFDs = fds', tcdSigs = sigs', tcdMeths = binds' + , tcdATs = ats', tcdDocs = [] } + -- no docs in TH ^^ } - where - isFamInstD (DataInstD _ _ _ _ _) = True - isFamInstD (NewtypeInstD _ _ _ _ _) = True - isFamInstD (TySynInstD _ _ _) = True - isFamInstD _ = False - -cvtTop (ForeignD ford) = do { ford' <- cvtForD ford; returnL $ ForD ford' } - -cvtTop (FamilyD flav tc tvs) - = do { (_, tc', tvs', _) <- cvt_tycl_hdr [] tc tvs - ; returnL $ TyClD (TyFamily (cvtFamFlavour flav) tc' tvs' Nothing) - -- FIXME: kinds - } + +cvtDec (InstanceD ctxt ty decs) + = do { (binds', sigs', ats') <- cvt_ci_decs (ptext (sLit "an instance declaration")) decs + ; ctxt' <- cvtContext ctxt + ; L loc pred' <- cvtPredTy ty + ; let inst_ty' = L loc $ mkImplicitHsForAllTy ctxt' $ L loc $ HsPredTy pred' + ; returnL $ InstD (InstDecl inst_ty' binds' sigs' ats') } + +cvtDec (ForeignD ford) + = do { ford' <- cvtForD ford + ; returnL $ ForD ford' } + +cvtDec (FamilyD flav tc tvs kind) + = do { (_, tc', tvs') <- cvt_tycl_hdr [] tc tvs + ; let kind' = fmap cvtKind kind + ; returnL $ TyClD (TyFamily (cvtFamFlavour flav) tc' tvs' kind') } where cvtFamFlavour TypeFam = TypeFamily cvtFamFlavour DataFam = DataFamily -cvtTop (DataInstD ctxt tc tys constrs derivs) - = do { stuff <- cvt_tyinst_hdr ctxt tc tys +cvtDec (DataInstD ctxt tc tys constrs derivs) + = do { (ctxt', tc', tvs', typats') <- cvt_tyinst_hdr ctxt tc tys ; cons' <- mapM cvtConstr constrs ; derivs' <- cvtDerivs derivs - ; returnL $ TyClD (mkTyData DataType stuff Nothing cons' derivs') - } + ; returnL $ TyClD (TyData { tcdND = DataType, tcdLName = tc', tcdCtxt = ctxt' + , tcdTyVars = tvs', tcdTyPats = typats', tcdKindSig = Nothing + , tcdCons = cons', tcdDerivs = derivs' }) } -cvtTop (NewtypeInstD ctxt tc tys constr derivs) - = do { stuff <- cvt_tyinst_hdr ctxt tc tys +cvtDec (NewtypeInstD ctxt tc tys constr derivs) + = do { (ctxt', tc', tvs', typats') <- cvt_tyinst_hdr ctxt tc tys ; con' <- cvtConstr constr ; derivs' <- cvtDerivs derivs - ; returnL $ TyClD (mkTyData NewType stuff Nothing [con'] derivs') + ; returnL $ TyClD (TyData { tcdND = NewType, tcdLName = tc', tcdCtxt = ctxt' + , tcdTyVars = tvs', tcdTyPats = typats', tcdKindSig = Nothing + , tcdCons = [con'], tcdDerivs = derivs' }) } -cvtTop (TySynInstD tc tys rhs) +cvtDec (TySynInstD tc tys rhs) = do { (_, tc', tvs', tys') <- cvt_tyinst_hdr [] tc tys ; rhs' <- cvtType rhs ; returnL $ TyClD (TySynonym tc' tvs' tys' rhs') } --- FIXME: This projection is not nice, but to remove it, cvtTop should be --- refactored. -unTyClD :: LHsDecl a -> LTyClDecl a -unTyClD (L l (TyClD d)) = L l d -unTyClD _ = panic "Convert.unTyClD: internal error" - -cvt_tycl_hdr :: TH.Cxt -> TH.Name -> [TH.Name] +---------------- +cvt_ci_decs :: Message -> [TH.Dec] + -> CvtM (LHsBinds RdrName, + [LSig RdrName], + [LTyClDecl RdrName]) +-- Convert the declarations inside a class or instance decl +-- ie signatures, bindings, and associated types +cvt_ci_decs doc decs + = do { decs' <- mapM cvtDec decs + ; let (ats', bind_sig_decs') = partitionWith is_tycl decs' + ; let (sigs', prob_binds') = partitionWith is_sig bind_sig_decs' + ; let (binds', bads) = partitionWith is_bind prob_binds' + ; unless (null bads) (failWith (mkBadDecMsg doc bads)) + ; return (listToBag binds', sigs', ats') } + +---------------- +cvt_tycl_hdr :: TH.Cxt -> TH.Name -> [TH.TyVarBndr] -> CvtM ( LHsContext RdrName , Located RdrName - , [LHsTyVarBndr RdrName] - , Maybe [LHsType RdrName]) + , [LHsTyVarBndr RdrName]) cvt_tycl_hdr cxt tc tvs = do { cxt' <- cvtContext cxt ; tc' <- tconNameL tc ; tvs' <- cvtTvs tvs - ; return (cxt', tc', tvs', Nothing) + ; return (cxt', tc', tvs') } cvt_tyinst_hdr :: TH.Cxt -> TH.Name -> [TH.Type] @@ -227,9 +265,10 @@ cvt_tyinst_hdr cxt tc tys where collect (ForallT _ _ _) = failWith $ text "Forall type not allowed as type parameter" - collect (VarT tv) = return [tv] + collect (VarT tv) = return [PlainTV tv] collect (ConT _) = return [] collect (TupleT _) = return [] + collect (UnboxedTupleT _) = return [] collect ArrowT = return [] collect ListT = return [] collect (AppT t1 t2) @@ -237,6 +276,29 @@ cvt_tyinst_hdr cxt tc tys ; tvs2 <- collect t2 ; return $ tvs1 ++ tvs2 } + collect (SigT (VarT tv) ki) = return [KindedTV tv ki] + collect (SigT ty _) = collect ty + +------------------------------------------------------------------- +-- Partitioning declarations +------------------------------------------------------------------- + +is_tycl :: LHsDecl RdrName -> Either (LTyClDecl RdrName) (LHsDecl RdrName) +is_tycl (L loc (Hs.TyClD tcd)) = Left (L loc tcd) +is_tycl decl = Right decl + +is_sig :: LHsDecl RdrName -> Either (LSig RdrName) (LHsDecl RdrName) +is_sig (L loc (Hs.SigD sig)) = Left (L loc sig) +is_sig decl = Right decl + +is_bind :: LHsDecl RdrName -> Either (LHsBind RdrName) (LHsDecl RdrName) +is_bind (L loc (Hs.ValD bind)) = Left (L loc bind) +is_bind decl = Right decl + +mkBadDecMsg :: Message -> [LHsDecl RdrName] -> Message +mkBadDecMsg doc bads + = sep [ ptext (sLit "Illegal declaration(s) in") <+> doc <> colon + , nest 2 (vcat (map Outputable.ppr bads)) ] --------------------------------------------------- -- Data types @@ -249,32 +311,27 @@ cvtConstr (NormalC c strtys) = do { c' <- cNameL c ; cxt' <- returnL [] ; tys' <- mapM cvt_arg strtys - ; returnL $ ConDecl c' Explicit noExistentials cxt' (PrefixCon tys') ResTyH98 Nothing } + ; returnL $ mkSimpleConDecl c' noExistentials cxt' (PrefixCon tys') } cvtConstr (RecC c varstrtys) = do { c' <- cNameL c ; cxt' <- returnL [] ; args' <- mapM cvt_id_arg varstrtys - ; returnL $ ConDecl c' Explicit noExistentials cxt' (RecCon args') ResTyH98 Nothing } + ; returnL $ mkSimpleConDecl c' noExistentials cxt' (RecCon args') } cvtConstr (InfixC st1 c st2) = do { c' <- cNameL c ; cxt' <- returnL [] ; st1' <- cvt_arg st1 ; st2' <- cvt_arg st2 - ; returnL $ ConDecl c' Explicit noExistentials cxt' (InfixCon st1' st2') ResTyH98 Nothing } - -cvtConstr (ForallC tvs ctxt (ForallC tvs' ctxt' con')) - = cvtConstr (ForallC (tvs ++ tvs') (ctxt ++ ctxt') con') + ; returnL $ mkSimpleConDecl c' noExistentials cxt' (InfixCon st1' st2') } cvtConstr (ForallC tvs ctxt con) - = do { L _ con' <- cvtConstr con - ; tvs' <- cvtTvs tvs - ; ctxt' <- cvtContext ctxt - ; case con' of - ConDecl l _ [] (L _ []) x ResTyH98 _ - -> returnL $ ConDecl l Explicit tvs' ctxt' x ResTyH98 Nothing - _ -> panic "ForallC: Can't happen" } + = do { tvs' <- cvtTvs tvs + ; L loc ctxt' <- cvtContext ctxt + ; L _ con' <- cvtConstr con + ; returnL $ con' { con_qvars = tvs' ++ con_qvars con' + , con_cxt = L loc (ctxt' ++ (unLoc $ con_cxt con')) } } cvt_arg :: (TH.Strict, TH.Type) -> CvtM (LHsType RdrName) cvt_arg (IsStrict, ty) = do { ty' <- cvtType ty; returnL $ HsBangTy HsStrict ty' } @@ -306,19 +363,20 @@ noExistentials = [] cvtForD :: Foreign -> CvtM (ForeignDecl RdrName) cvtForD (ImportF callconv safety from nm ty) - | Just (c_header, cis) <- parse_ccall_impent (TH.nameBase nm) from - = do { nm' <- vNameL nm - ; ty' <- cvtType ty - ; let i = CImport (cvt_conv callconv) safety' c_header nilFS cis - ; return $ ForeignImport nm' ty' i } - + | Just impspec <- parseCImport (cvt_conv callconv) safety' + (mkFastString (TH.nameBase nm)) from + = do { nm' <- vNameL nm + ; ty' <- cvtType ty + ; return (ForeignImport nm' ty' impspec) + } | otherwise - = failWith $ text (show from)<+> ptext (sLit "is not a valid ccall impent") - where + = failWith $ text (show from) <+> ptext (sLit "is not a valid ccall impent") + where safety' = case safety of Unsafe -> PlayRisky Safe -> PlaySafe False Threadsafe -> PlaySafe True + Interruptible -> PlayInterruptible cvtForD (ExportF callconv as nm ty) = do { nm' <- vNameL nm @@ -330,105 +388,62 @@ cvt_conv :: TH.Callconv -> CCallConv cvt_conv TH.CCall = CCallConv cvt_conv TH.StdCall = StdCallConv -parse_ccall_impent :: String -> String -> Maybe (FastString, CImportSpec) -parse_ccall_impent nm s - = case lex_ccall_impent s of - Just ["dynamic"] -> Just (nilFS, CFunction DynamicTarget) - Just ["wrapper"] -> Just (nilFS, CWrapper) - Just ("static":ts) -> parse_ccall_impent_static nm ts - Just ts -> parse_ccall_impent_static nm ts - Nothing -> Nothing - -parse_ccall_impent_static :: String - -> [String] - -> Maybe (FastString, CImportSpec) -parse_ccall_impent_static nm ts - = let ts' = case ts of - [ "&", cid] -> [ cid] - [fname, "&" ] -> [fname ] - [fname, "&", cid] -> [fname, cid] - _ -> ts - in case ts' of - [ cid] | is_cid cid -> Just (nilFS, mk_cid cid) - [fname, cid] | is_cid cid -> Just (mkFastString fname, mk_cid cid) - [ ] -> Just (nilFS, mk_cid nm) - [fname ] -> Just (mkFastString fname, mk_cid nm) - _ -> Nothing - where is_cid :: String -> Bool - is_cid x = all (/= '.') x && (isAlpha (head x) || head x == '_') - mk_cid :: String -> CImportSpec - mk_cid = CFunction . StaticTarget . mkFastString - -lex_ccall_impent :: String -> Maybe [String] -lex_ccall_impent "" = Just [] -lex_ccall_impent ('&':xs) = fmap ("&":) $ lex_ccall_impent xs -lex_ccall_impent (' ':xs) = lex_ccall_impent xs -lex_ccall_impent ('\t':xs) = lex_ccall_impent xs -lex_ccall_impent xs = case span is_valid xs of - ("", _) -> Nothing - (t, xs') -> fmap (t:) $ lex_ccall_impent xs' - where is_valid :: Char -> Bool - is_valid c = isAscii c && (isAlphaNum c || c `elem` "._") +------------------------------------------ +-- Pragmas +------------------------------------------ +cvtPragmaD :: Pragma -> CvtM (Sig RdrName) +cvtPragmaD (InlineP nm ispec) + = do { nm' <- vNameL nm + ; return $ InlineSig nm' (cvtInlineSpec (Just ispec)) } + +cvtPragmaD (SpecialiseP nm ty opt_ispec) + = do { nm' <- vNameL nm + ; ty' <- cvtType ty + ; return $ SpecSig nm' ty' (cvtInlineSpec opt_ispec) } + +cvtInlineSpec :: Maybe TH.InlineSpec -> Hs.InlinePragma +cvtInlineSpec Nothing + = defaultInlinePragma +cvtInlineSpec (Just (TH.InlineSpec inline conlike opt_activation)) + = InlinePragma { inl_act = opt_activation', inl_rule = matchinfo + , inl_inline = inl_spec, inl_sat = Nothing } + where + matchinfo = cvtRuleMatchInfo conlike + opt_activation' = cvtActivation opt_activation + + cvtRuleMatchInfo False = FunLike + cvtRuleMatchInfo True = ConLike + + inl_spec | inline = Inline + | otherwise = NoInline + -- Currently we have no way to say Inlinable + + cvtActivation Nothing | inline = AlwaysActive + | otherwise = NeverActive + cvtActivation (Just (False, phase)) = ActiveBefore phase + cvtActivation (Just (True , phase)) = ActiveAfter phase --------------------------------------------------- -- Declarations --------------------------------------------------- -cvtDecs :: [TH.Dec] -> CvtM (HsLocalBinds RdrName) -cvtDecs [] = return EmptyLocalBinds -cvtDecs ds = do { (binds,sigs) <- cvtBindsAndSigs ds - ; return (HsValBinds (ValBindsIn binds sigs)) } - -cvtBindsAndSigs :: [TH.Dec] -> CvtM (Bag (LHsBind RdrName), [LSig RdrName]) -cvtBindsAndSigs ds - = do { binds' <- mapM cvtBind binds; sigs' <- mapM cvtSig sigs - ; return (listToBag binds', sigs') } - where - (sigs, binds) = partition is_sig ds - - is_sig (TH.SigD _ _) = True - is_sig _ = False - -cvtSig :: TH.Dec -> CvtM (LSig RdrName) -cvtSig (TH.SigD nm ty) - = do { nm' <- vNameL nm; ty' <- cvtType ty; returnL (Hs.TypeSig nm' ty') } -cvtSig _ = panic "Convert.cvtSig: Signature expected" - -cvtBind :: TH.Dec -> CvtM (LHsBind RdrName) --- Used only for declarations in a 'let/where' clause, --- not for top level decls -cvtBind (TH.ValD (TH.VarP s) body ds) - = do { s' <- vNameL s - ; cl' <- cvtClause (Clause [] body ds) - ; returnL $ mkFunBind s' [cl'] } - -cvtBind (TH.FunD nm cls) - | null cls - = failWith (ptext (sLit "Function binding for") - <+> quotes (text (TH.pprint nm)) - <+> ptext (sLit "has no equations")) +cvtLocalDecs :: Message -> [TH.Dec] -> CvtM (HsLocalBinds RdrName) +cvtLocalDecs doc ds + | null ds + = return EmptyLocalBinds | otherwise - = do { nm' <- vNameL nm - ; cls' <- mapM cvtClause cls - ; returnL $ mkFunBind nm' cls' } - -cvtBind (TH.ValD p body ds) - = do { p' <- cvtPat p - ; g' <- cvtGuard body - ; ds' <- cvtDecs ds - ; returnL $ PatBind { pat_lhs = p', pat_rhs = GRHSs g' ds', - pat_rhs_ty = void, bind_fvs = placeHolderNames } } - -cvtBind d - = failWith (sep [ptext (sLit "Illegal kind of declaration in where clause"), - nest 2 (text (TH.pprint d))]) + = do { ds' <- mapM cvtDec ds + ; let (binds, prob_sigs) = partitionWith is_bind ds' + ; let (sigs, bads) = partitionWith is_sig prob_sigs + ; unless (null bads) (failWith (mkBadDecMsg doc bads)) + ; return (HsValBinds (ValBindsIn (listToBag binds) sigs)) } cvtClause :: TH.Clause -> CvtM (Hs.LMatch RdrName) cvtClause (Clause ps body wheres) = do { ps' <- cvtPats ps ; g' <- cvtGuard body - ; ds' <- cvtDecs wheres + ; ds' <- cvtLocalDecs (ptext (sLit "a where clause")) wheres ; returnL $ Hs.Match ps' Nothing (GRHSs g' ds') } @@ -449,10 +464,13 @@ cvtl e = wrapL (cvt e) cvt (LamE ps e) = do { ps' <- cvtPats ps; e' <- cvtl e ; return $ HsLam (mkMatchGroup [mkSimpleMatch ps' e']) } cvt (TupE [e]) = cvt e -- Singleton tuples treated like nothing (just parens) - cvt (TupE es) = do { es' <- mapM cvtl es; return $ ExplicitTuple es' Boxed } - cvt (CondE x y z) = do { x' <- cvtl x; y' <- cvtl y; z' <- cvtl z - ; return $ HsIf x' y' z' } - cvt (LetE ds e) = do { ds' <- cvtDecs ds; e' <- cvtl e; return $ HsLet ds' e' } + cvt (TupE es) = do { es' <- mapM cvtl es; return $ ExplicitTuple (map Present es') Boxed } + cvt (UnboxedTupE [e]) = cvt e -- Singleton tuples treated like nothing (just parens) + cvt (UnboxedTupE es) = do { es' <- mapM cvtl es; return $ ExplicitTuple (map Present es') Unboxed } + cvt (CondE x y z) = do { x' <- cvtl x; y' <- cvtl y; z' <- cvtl z; + ; return $ HsIf (Just noSyntaxExpr) x' y' z' } + cvt (LetE ds e) = do { ds' <- cvtLocalDecs (ptext (sLit "a let expression")) ds + ; e' <- cvtl e; return $ HsLet ds' e' } cvt (CaseE e ms) | null ms = failWith (ptext (sLit "Case expression with no alternatives")) | otherwise = do { e' <- cvtl e; ms' <- mapM cvtMatch ms @@ -460,7 +478,10 @@ cvtl e = wrapL (cvt e) cvt (DoE ss) = cvtHsDo DoExpr ss cvt (CompE ss) = cvtHsDo ListComp ss cvt (ArithSeqE dd) = do { dd' <- cvtDD dd; return $ ArithSeq noPostTcExpr dd' } - cvt (ListE xs) = do { xs' <- mapM cvtl xs; return $ ExplicitList void xs' } + cvt (ListE xs) + | Just s <- allCharLs xs = do { l' <- cvtLit (StringL s); return (HsLit l') } + -- Note [Converting strings] + | otherwise = do { xs' <- mapM cvtl xs; return $ ExplicitList void xs' } cvt (InfixE (Just x) s (Just y)) = do { x' <- cvtl x; s' <- cvtl s; y' <- cvtl y ; e' <- returnL $ OpApp x' s' undefined y' ; return $ HsPar e' } @@ -501,19 +522,27 @@ cvtHsDo do_or_lc stmts | null stmts = failWith (ptext (sLit "Empty stmt list in do-block")) | otherwise = do { stmts' <- cvtStmts stmts - ; let body = case last stmts' of - L _ (ExprStmt body _ _) -> body - _ -> panic "Malformed body" - ; return $ HsDo do_or_lc (init stmts') body void } + ; let Just (stmts'', last') = snocView stmts' + + ; last'' <- case last' of + L loc (ExprStmt body _ _ _) -> return (L loc (mkLastStmt body)) + _ -> failWith (bad_last last') + ; return $ HsDo do_or_lc (stmts'' ++ [last'']) void } + where + bad_last stmt = vcat [ ptext (sLit "Illegal last statement of") <+> pprAStmtContext do_or_lc <> colon + , nest 2 $ Outputable.ppr stmt + , ptext (sLit "(It should be an expression.)") ] + cvtStmts :: [TH.Stmt] -> CvtM [Hs.LStmt RdrName] cvtStmts = mapM cvtStmt cvtStmt :: TH.Stmt -> CvtM (Hs.LStmt RdrName) cvtStmt (NoBindS e) = do { e' <- cvtl e; returnL $ mkExprStmt e' } cvtStmt (TH.BindS p e) = do { p' <- cvtPat p; e' <- cvtl e; returnL $ mkBindStmt p' e' } -cvtStmt (TH.LetS ds) = do { ds' <- cvtDecs ds; returnL $ LetStmt ds' } -cvtStmt (TH.ParS dss) = do { dss' <- mapM cvt_one dss; returnL $ ParStmt dss' } +cvtStmt (TH.LetS ds) = do { ds' <- cvtLocalDecs (ptext (sLit "a let binding")) ds + ; returnL $ LetStmt ds' } +cvtStmt (TH.ParS dss) = do { dss' <- mapM cvt_one dss; returnL $ ParStmt dss' noSyntaxExpr noSyntaxExpr noSyntaxExpr } where cvt_one ds = do { ds' <- cvtStmts ds; return (ds', undefined) } @@ -521,7 +550,7 @@ cvtMatch :: TH.Match -> CvtM (Hs.LMatch RdrName) cvtMatch (TH.Match p body decs) = do { p' <- cvtPat p ; g' <- cvtGuard body - ; decs' <- cvtDecs decs + ; decs' <- cvtLocalDecs (ptext (sLit "a where clause")) decs ; returnL $ Hs.Match [p'] Nothing (GRHSs g' decs') } cvtGuard :: TH.Body -> CvtM [LGRHS RdrName] @@ -539,7 +568,7 @@ cvtOverLit :: Lit -> CvtM (HsOverLit RdrName) cvtOverLit (IntegerL i) = do { force i; return $ mkHsIntegral i placeHolderType} cvtOverLit (RationalL r) - = do { force r; return $ mkHsFractional r placeHolderType} + = do { force r; return $ mkHsFractional (cvtFractionalLit r) placeHolderType} cvtOverLit (StringL s) = do { let { s' = mkFastString s } ; force s' @@ -549,18 +578,43 @@ cvtOverLit _ = panic "Convert.cvtOverLit: Unexpected overloaded literal" -- An Integer is like an (overloaded) '3' in a Haskell source program -- Similarly 3.5 for fractionals +{- Note [Converting strings] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +If we get (ListE [CharL 'x', CharL 'y']) we'd like to convert to +a string literal for "xy". Of course, we might hope to get +(LitE (StringL "xy")), but not always, and allCharLs fails quickly +if it isn't a literal string +-} + +allCharLs :: [TH.Exp] -> Maybe String +-- Note [Converting strings] +-- NB: only fire up this setup for a non-empty list, else +-- there's a danger of returning "" for [] :: [Int]! +allCharLs xs + = case xs of + LitE (CharL c) : ys -> go [c] ys + _ -> Nothing + where + go cs [] = Just (reverse cs) + go cs (LitE (CharL c) : ys) = go (c:cs) ys + go _ _ = Nothing + cvtLit :: Lit -> CvtM HsLit cvtLit (IntPrimL i) = do { force i; return $ HsIntPrim i } cvtLit (WordPrimL w) = do { force w; return $ HsWordPrim w } -cvtLit (FloatPrimL f) = do { force f; return $ HsFloatPrim f } -cvtLit (DoublePrimL f) = do { force f; return $ HsDoublePrim f } +cvtLit (FloatPrimL f) = do { force f; return $ HsFloatPrim (cvtFractionalLit f) } +cvtLit (DoublePrimL f) = do { force f; return $ HsDoublePrim (cvtFractionalLit f) } cvtLit (CharL c) = do { force c; return $ HsChar c } -cvtLit (StringL s) - = do { let { s' = mkFastString s } - ; force s' - ; return $ HsString s' - } +cvtLit (StringL s) = do { let { s' = mkFastString s } + ; force s' + ; return $ HsString s' } +cvtLit (StringPrimL s) = do { let { s' = mkFastString s } + ; force s' + ; return $ HsStringPrim s' } cvtLit _ = panic "Convert.cvtLit: Unexpected literal" + -- cvtLit should not be called on IntegerL, RationalL + -- That precondition is established right here in + -- Convert.lhs, hence panic cvtPats :: [TH.Pat] -> CvtM [Hs.LPat RdrName] cvtPats pats = mapM cvtPat pats @@ -578,16 +632,20 @@ cvtp (TH.LitP l) cvtp (TH.VarP s) = do { s' <- vName s; return $ Hs.VarPat s' } cvtp (TupP [p]) = cvtp p cvtp (TupP ps) = do { ps' <- cvtPats ps; return $ TuplePat ps' Boxed void } +cvtp (UnboxedTupP [p]) = cvtp p +cvtp (UnboxedTupP ps) = do { ps' <- cvtPats ps; return $ TuplePat ps' Unboxed void } cvtp (ConP s ps) = do { s' <- cNameL s; ps' <- cvtPats ps; return $ ConPatIn s' (PrefixCon ps') } cvtp (InfixP p1 s p2) = do { s' <- cNameL s; p1' <- cvtPat p1; p2' <- cvtPat p2 ; return $ ConPatIn s' (InfixCon p1' p2') } cvtp (TildeP p) = do { p' <- cvtPat p; return $ LazyPat p' } +cvtp (BangP p) = do { p' <- cvtPat p; return $ BangPat p' } cvtp (TH.AsP s p) = do { s' <- vNameL s; p' <- cvtPat p; return $ AsPat s' p' } cvtp TH.WildP = return $ WildPat void cvtp (RecP c fs) = do { c' <- cNameL c; fs' <- mapM cvtPatFld fs ; return $ ConPatIn c' $ Hs.RecCon (HsRecFields fs' Nothing) } cvtp (ListP ps) = do { ps' <- cvtPats ps; return $ ListPat ps' void } cvtp (SigP p t) = do { p' <- cvtPat p; t' <- cvtType t; return $ SigPatIn p' t' } +cvtp (ViewP e p) = do { e' <- cvtl e; p' <- cvtPat p; return $ ViewPat e' p' void } cvtPatFld :: (TH.Name, TH.Pat) -> CvtM (HsRecField RdrName (LPat RdrName)) cvtPatFld (s,p) @@ -597,45 +655,89 @@ cvtPatFld (s,p) ----------------------------------------------------------- -- Types and type variables -cvtTvs :: [TH.Name] -> CvtM [LHsTyVarBndr RdrName] +cvtTvs :: [TH.TyVarBndr] -> CvtM [LHsTyVarBndr RdrName] cvtTvs tvs = mapM cvt_tv tvs -cvt_tv :: TH.Name -> CvtM (LHsTyVarBndr RdrName) -cvt_tv tv = do { tv' <- tName tv; returnL $ UserTyVar tv' } +cvt_tv :: TH.TyVarBndr -> CvtM (LHsTyVarBndr RdrName) +cvt_tv (TH.PlainTV nm) + = do { nm' <- tName nm + ; returnL $ UserTyVar nm' placeHolderKind + } +cvt_tv (TH.KindedTV nm ki) + = do { nm' <- tName nm + ; returnL $ KindedTyVar nm' (cvtKind ki) + } -cvtContext :: Cxt -> CvtM (LHsContext RdrName) +cvtContext :: TH.Cxt -> CvtM (LHsContext RdrName) cvtContext tys = do { preds' <- mapM cvtPred tys; returnL preds' } -cvtPred :: TH.Type -> CvtM (LHsPred RdrName) -cvtPred ty +cvtPred :: TH.Pred -> CvtM (LHsPred RdrName) +cvtPred (TH.ClassP cla tys) + = do { cla' <- if isVarName cla then tName cla else tconName cla + ; tys' <- mapM cvtType tys + ; returnL $ HsClassP cla' tys' + } +cvtPred (TH.EqualP ty1 ty2) + = do { ty1' <- cvtType ty1 + ; ty2' <- cvtType ty2 + ; returnL $ HsEqualP ty1' ty2' + } + +cvtPredTy :: TH.Type -> CvtM (LHsPred RdrName) +cvtPredTy ty = do { (head, tys') <- split_ty_app ty ; case head of ConT tc -> do { tc' <- tconName tc; returnL $ HsClassP tc' tys' } VarT tv -> do { tv' <- tName tv; returnL $ HsClassP tv' tys' } - _ -> failWith (ptext (sLit "Malformed predicate") <+> text (TH.pprint ty)) } + _ -> failWith (ptext (sLit "Malformed predicate") <+> + text (TH.pprint ty)) } cvtType :: TH.Type -> CvtM (LHsType RdrName) -cvtType ty = do { (head_ty, tys') <- split_ty_app ty - ; case head_ty of - TupleT n | length tys' == n -- Saturated - -> if n==1 then return (head tys') -- Singleton tuples treated - -- like nothing (ie just parens) - else returnL (HsTupleTy Boxed tys') - | n == 1 -> failWith (ptext (sLit "Illegal 1-tuple type constructor")) - | otherwise -> mk_apps (HsTyVar (getRdrName (tupleTyCon Boxed n))) tys' - ArrowT | [x',y'] <- tys' -> returnL (HsFunTy x' y') - | otherwise -> mk_apps (HsTyVar (getRdrName funTyCon)) tys' - ListT | [x'] <- tys' -> returnL (HsListTy x') - | otherwise -> mk_apps (HsTyVar (getRdrName listTyCon)) tys' - VarT nm -> do { nm' <- tName nm; mk_apps (HsTyVar nm') tys' } - ConT nm -> do { nm' <- tconName nm; mk_apps (HsTyVar nm') tys' } - - ForallT tvs cxt ty | null tys' -> do { tvs' <- cvtTvs tvs - ; cxt' <- cvtContext cxt - ; ty' <- cvtType ty - ; returnL $ mkExplicitHsForAllTy tvs' cxt' ty' } - _ -> failWith (ptext (sLit "Malformed type") <+> text (show ty)) - } +cvtType ty + = do { (head_ty, tys') <- split_ty_app ty + ; case head_ty of + TupleT n + | length tys' == n -- Saturated + -> if n==1 then return (head tys') -- Singleton tuples treated + -- like nothing (ie just parens) + else returnL (HsTupleTy Boxed tys') + | n == 1 + -> failWith (ptext (sLit "Illegal 1-tuple type constructor")) + | otherwise + -> mk_apps (HsTyVar (getRdrName (tupleTyCon Boxed n))) tys' + UnboxedTupleT n + | length tys' == n -- Saturated + -> if n==1 then return (head tys') -- Singleton tuples treated + -- like nothing (ie just parens) + else returnL (HsTupleTy Unboxed tys') + | n == 1 + -> failWith (ptext (sLit "Illegal 1-unboxed-tuple type constructor")) + | otherwise + -> mk_apps (HsTyVar (getRdrName (tupleTyCon Unboxed n))) tys' + ArrowT + | [x',y'] <- tys' -> returnL (HsFunTy x' y') + | otherwise -> mk_apps (HsTyVar (getRdrName funTyCon)) tys' + ListT + | [x'] <- tys' -> returnL (HsListTy x') + | otherwise -> mk_apps (HsTyVar (getRdrName listTyCon)) tys' + VarT nm -> do { nm' <- tName nm; mk_apps (HsTyVar nm') tys' } + ConT nm -> do { nm' <- tconName nm; mk_apps (HsTyVar nm') tys' } + + ForallT tvs cxt ty + | null tys' + -> do { tvs' <- cvtTvs tvs + ; cxt' <- cvtContext cxt + ; ty' <- cvtType ty + ; returnL $ mkExplicitHsForAllTy tvs' cxt' ty' + } + + SigT ty ki + -> do { ty' <- cvtType ty + ; mk_apps (HsKindSig ty' (cvtKind ki)) tys' + } + + _ -> failWith (ptext (sLit "Malformed type") <+> text (show ty)) + } where mk_apps head_ty [] = returnL head_ty mk_apps head_ty (ty:tys) = do { head_ty' <- returnL head_ty @@ -647,6 +749,10 @@ split_ty_app ty = go ty [] go (AppT f a) as' = do { a' <- cvtType a; go f (a':as') } go f as = return (f,as) +cvtKind :: TH.Kind -> Type.Kind +cvtKind StarK = liftedTypeKind +cvtKind (ArrowK k1 k2) = mkArrowKind (cvtKind k1) (cvtKind k2) + ----------------------------------------------------------- @@ -662,6 +768,9 @@ overloadedLit _ = False void :: Type.Type void = placeHolderType +cvtFractionalLit :: Rational -> FractionalLit +cvtFractionalLit r = FL { fl_text = show (fromRational r :: Double), fl_value = r } + -------------------------------------------------------------------- -- Turning Name back into RdrName -------------------------------------------------------------------- @@ -687,9 +796,10 @@ tconName n = cvtName OccName.tcClsName n cvtName :: OccName.NameSpace -> TH.Name -> CvtM RdrName cvtName ctxt_ns (TH.Name occ flavour) | not (okOcc ctxt_ns occ_str) = failWith (badOcc ctxt_ns occ_str) - | otherwise = force (thRdrName ctxt_ns occ_str flavour) + | otherwise = force rdr_name >> return rdr_name where occ_str = TH.occString occ + rdr_name = thRdrName ctxt_ns occ_str flavour okOcc :: OccName.NameSpace -> String -> Bool okOcc _ [] = False @@ -697,6 +807,14 @@ okOcc ns str@(c:_) | OccName.isVarNameSpace ns = startsVarId c || startsVarSym c | otherwise = startsConId c || startsConSym c || str == "[]" +-- Determine the name space of a name in a type +-- +isVarName :: TH.Name -> Bool +isVarName (TH.Name occ _) + = case TH.occString occ of + "" -> False + (c:_) -> startsVarId c || startsVarSym c + badOcc :: OccName.NameSpace -> String -> SDoc badOcc ctxt_ns occ = ptext (sLit "Illegal") <+> pprNameSpace ctxt_ns @@ -758,14 +876,7 @@ isBuiltInOcc ctxt_ns occ mk_uniq_occ :: OccName.NameSpace -> String -> Int# -> OccName.OccName mk_uniq_occ ns occ uniq = OccName.mkOccName ns (occ ++ '[' : shows (mk_uniq uniq) "]") - -- The idea here is to make a name that - -- a) the user could not possibly write, and - -- b) cannot clash with another NameU - -- Previously I generated an Exact RdrName with mkInternalName. - -- This works fine for local binders, but does not work at all for - -- top-level binders, which must have External Names, since they are - -- rapidly baked into data constructors and the like. Baling out - -- and generating an unqualified RdrName here is the simple solution + -- See Note [Unique OccNames from Template Haskell] -- The packing and unpacking is rather turgid :-( mk_occ :: OccName.NameSpace -> String -> OccName.OccName @@ -779,10 +890,24 @@ mk_ghc_ns TH.VarName = OccName.varName mk_mod :: TH.ModName -> ModuleName mk_mod mod = mkModuleName (TH.modString mod) -mk_pkg :: TH.ModName -> PackageId +mk_pkg :: TH.PkgName -> PackageId mk_pkg pkg = stringToPackageId (TH.pkgString pkg) mk_uniq :: Int# -> Unique mk_uniq u = mkUniqueGrimily (I# u) \end{code} +Note [Unique OccNames from Template Haskell] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +The idea here is to make a name that + a) the user could not possibly write (it has a "[" + and letters or digits from the unique) + b) cannot clash with another NameU +Previously I generated an Exact RdrName with mkInternalName. This +works fine for local binders, but does not work at all for top-level +binders, which must have External Names, since they are rapidly baked +into data constructors and the like. Baling out and generating an +unqualified RdrName here is the simple solution + +See also Note [Suppressing uniques in OccNames] in OccName, which +suppresses the unique when opt_SuppressUniques is on.