X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FhsSyn%2FConvert.lhs;h=fc5f897afb3e3a3719d965f9812f0255e8f84317;hp=71cfaaf495d364a7d42a0ffc5e34b36eb1c02e75;hb=83d563cb9ede0ba792836e529b1e2929db926355;hpb=ab22f4e6456820c1b5169d75f5975a94e61f54ce diff --git a/compiler/hsSyn/Convert.lhs b/compiler/hsSyn/Convert.lhs index 71cfaaf..fc5f897 100644 --- a/compiler/hsSyn/Convert.lhs +++ b/compiler/hsSyn/Convert.lhs @@ -6,10 +6,9 @@ This module converts Template Haskell syntax into HsSyn \begin{code} -module Convert( convertToHsExpr, convertToHsDecls, - convertToHsType, thRdrName ) where - -#include "HsVersions.h" +module Convert( convertToHsExpr, convertToPat, convertToHsDecls, + convertToHsType, convertToHsPred, + thRdrNameGuesses ) where import HsSyn as Hs import qualified Class @@ -18,21 +17,23 @@ import qualified Name import Module import RdrHsSyn import qualified OccName -import PackageConfig 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 @@ -42,18 +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 $$ (ptext SLIT("When converting TH expression") - <+> text (show e))) - Right res -> Right res + = initCvt loc $ wrapMsg "expression" e $ cvtl e + +convertToPat :: SrcSpan -> TH.Pat -> Either Message (LPat RdrName) +convertToPat loc p + = initCvt loc $ wrapMsg "pattern" p $ cvtPat p convertToHsType :: SrcSpan -> TH.Type -> Either Message (LHsType RdrName) -convertToHsType loc t = initCvt loc (cvtType t) +convertToHsType loc t + = initCvt loc $ wrapMsg "type" t $ cvtType t +convertToHsPred :: SrcSpan -> TH.Pred -> Either Message (LHsPred RdrName) +convertToHsPred loc t + = initCvt loc $ wrapMsg "type" t $ cvtPred t ------------------------------------------------------------------- newtype CvtM a = CvtM { unCvtM :: SrcSpan -> Either Message a } @@ -70,7 +78,7 @@ newtype CvtM a = CvtM { unCvtM :: SrcSpan -> Either Message a } -- the spliced-in declarations get a location that at least relates to the splice point instance Monad CvtM where - return x = CvtM $ \loc -> Right x + return x = CvtM $ \_ -> Right x (CvtM m) >>= k = CvtM $ \loc -> case m loc of Left err -> Left err Right v -> unCvtM (k v) loc @@ -78,117 +86,263 @@ instance Monad CvtM where initCvt :: SrcSpan -> CvtM a -> Either Message a initCvt loc (CvtM m) = m loc -force :: a -> CvtM a -force a = a `seq` return a +force :: a -> CvtM () +force a = a `seq` return () failWith :: Message -> CvtM a -failWith m = CvtM (\loc -> Left full_msg) - where - full_msg = m $$ 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') } -cvtTop d@(TH.FunD _ _) = do { L loc d' <- cvtBind d; return (L loc $ Hs.ValD d') } -cvtTop (TH.SigD nm typ) = do { nm' <- vNameL nm - ; ty' <- cvtType typ - ; returnL $ Hs.SigD (TypeSig nm' ty') } - -cvtTop (TySynD tc tvs rhs) - = do { tc' <- tconNameL tc - ; tvs' <- cvtTvs tvs +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'] } + + | 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' } + +cvtDec (TH.SigD nm typ) + = do { nm' <- vNameL nm + ; ty' <- cvtType typ + ; returnL $ Hs.SigD (TypeSig nm' ty') } + +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 - ; (binds', sigs') <- cvtBindsAndSigs decs - ; returnL $ TyClD $ mkClassDecl (cxt', tc', tvs') fds' sigs' binds' [] [] - -- no ATs or docs in TH ^^ ^^ + ; (binds', sigs', ats') <- cvt_ci_decs (ptext (sLit "a class declaration")) decs + ; returnL $ + TyClD $ ClassDecl { tcdCtxt = cxt', tcdLName = tc', tcdTyVars = tvs' + , tcdFDs = fds', tcdSigs = sigs', tcdMeths = binds' + , tcdATs = ats', tcdDocs = [] } + -- no docs in TH ^^ } + +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 + +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 (TyData { tcdND = DataType, tcdLName = tc', tcdCtxt = ctxt' + , tcdTyVars = tvs', tcdTyPats = typats', tcdKindSig = Nothing + , tcdCons = cons', tcdDerivs = derivs' }) } + +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 (TyData { tcdND = NewType, tcdLName = tc', tcdCtxt = ctxt' + , tcdTyVars = tvs', tcdTyPats = typats', tcdKindSig = Nothing + , tcdCons = [con'], tcdDerivs = derivs' }) + } + +cvtDec (TySynInstD tc tys rhs) + = do { (_, tc', tvs', tys') <- cvt_tyinst_hdr [] tc tys + ; rhs' <- cvtType rhs + ; returnL $ TyClD (TySynonym tc' tvs' tys' rhs') } + +---------------- +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]) +cvt_tycl_hdr cxt tc tvs + = do { cxt' <- cvtContext cxt + ; tc' <- tconNameL tc + ; tvs' <- cvtTvs tvs + ; return (cxt', tc', tvs') + } + +cvt_tyinst_hdr :: TH.Cxt -> TH.Name -> [TH.Type] + -> CvtM ( LHsContext RdrName + , Located RdrName + , [LHsTyVarBndr RdrName] + , Maybe [LHsType RdrName]) +cvt_tyinst_hdr cxt tc tys + = do { cxt' <- cvtContext cxt + ; tc' <- tconNameL tc + ; tvs <- concatMapM collect tys + ; tvs' <- cvtTvs tvs + ; tys' <- mapM cvtType tys + ; return (cxt', tc', tvs', Just tys') + } + where + collect (ForallT _ _ _) + = failWith $ text "Forall type not allowed as type parameter" + collect (VarT tv) = return [PlainTV tv] + collect (ConT _) = return [] + collect (TupleT _) = return [] + collect ArrowT = return [] + collect ListT = return [] + collect (AppT t1 t2) + = do { tvs1 <- collect t1 + ; tvs2 <- collect t2 + ; return $ tvs1 ++ tvs2 + } + collect (SigT (VarT tv) ki) = return [KindedTV tv ki] + collect (SigT ty _) = collect ty -cvtTop (InstanceD tys ty decs) - = do { (binds', sigs') <- cvtBindsAndSigs decs - ; ctxt' <- cvtContext tys - ; L loc pred' <- cvtPred ty - ; inst_ty' <- returnL $ mkImplicitHsForAllTy ctxt' (L loc (HsPredTy pred')) - ; returnL $ InstD (InstDecl inst_ty' binds' sigs' []) - -- ^^no ATs in TH - } +------------------------------------------------------------------- +-- Partitioning declarations +------------------------------------------------------------------- -cvtTop (ForeignD ford) = do { ford' <- cvtForD ford; returnL $ ForD ford' } +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 -cvt_tycl_hdr cxt tc tvs - = do { cxt' <- cvtContext cxt - ; tc' <- tconNameL tc - ; tvs' <- cvtTvs tvs - ; return (cxt', tc', tvs', Nothing) } +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 -- Can't handle GADTs yet --------------------------------------------------- +cvtConstr :: TH.Con -> CvtM (LConDecl RdrName) + 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 - c -> 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' } cvt_arg (NotStrict, ty) = cvtType ty -cvt_id_arg (i, str, ty) = do { i' <- vNameL i - ; ty' <- cvt_arg (str,ty) - ; return (mkRecField i' ty') } +cvt_id_arg :: (TH.Name, TH.Strict, TH.Type) -> CvtM (ConDeclField RdrName) +cvt_id_arg (i, str, ty) + = do { i' <- vNameL i + ; ty' <- cvt_arg (str,ty) + ; return (ConDeclField { cd_fld_name = i', cd_fld_type = ty', cd_fld_doc = Nothing}) } +cvtDerivs :: [TH.Name] -> CvtM (Maybe [LHsType RdrName]) cvtDerivs [] = return Nothing cvtDerivs cs = do { cs' <- mapM cvt_one cs ; return (Just cs') } @@ -199,6 +353,7 @@ cvtDerivs cs = do { cs' <- mapM cvt_one cs cvt_fundep :: FunDep -> CvtM (Located (Class.FunDep RdrName)) cvt_fundep (FunDep xs ys) = do { xs' <- mapM tName xs; ys' <- mapM tName ys; returnL (xs', ys') } +noExistentials :: [LHsTyVarBndr RdrName] noExistentials = [] ------------------------------------------ @@ -207,19 +362,20 @@ 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 @@ -227,100 +383,66 @@ cvtForD (ExportF callconv as nm ty) ; let e = CExport (CExportStatic (mkFastString as) (cvt_conv callconv)) ; return $ ForeignExport nm' ty' e } +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` "._") - - ---------------------------------------------------- --- Declarations ---------------------------------------------------- - -cvtDecs :: [TH.Dec] -> CvtM (HsLocalBinds RdrName) -cvtDecs [] = return EmptyLocalBinds -cvtDecs ds = do { (binds,sigs) <- cvtBindsAndSigs ds - ; return (HsValBinds (ValBindsIn binds sigs)) } - -cvtBindsAndSigs ds - = do { binds' <- mapM cvtBind binds; sigs' <- mapM cvtSig sigs - ; return (listToBag binds', sigs') } - where - (sigs, binds) = partition is_sig ds +------------------------------------------ +-- Pragmas +------------------------------------------ - is_sig (TH.SigD _ _) = True - is_sig other = False +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 -cvtSig (TH.SigD nm ty) - = do { nm' <- vNameL nm; ty' <- cvtType ty; returnL (Hs.TypeSig nm' ty') } + cvtRuleMatchInfo False = FunLike + cvtRuleMatchInfo True = ConLike -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'] } + inl_spec | inline = Inline + | otherwise = NoInline + -- Currently we have no way to say Inlinable -cvtBind (TH.FunD nm cls) - = do { nm' <- vNameL nm - ; cls' <- mapM cvtClause cls - ; returnL $ mkFunBind nm' cls' } + cvtActivation Nothing | inline = AlwaysActive + | otherwise = NeverActive + cvtActivation (Just (False, phase)) = ActiveBefore phase + cvtActivation (Just (True , phase)) = ActiveAfter phase -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 } } +--------------------------------------------------- +-- Declarations +--------------------------------------------------- -cvtBind d - = failWith (sep [ptext SLIT("Illegal kind of declaration in where clause"), - nest 2 (text (TH.pprint d))]) +cvtLocalDecs :: Message -> [TH.Dec] -> CvtM (HsLocalBinds RdrName) +cvtLocalDecs doc ds + | null ds + = return EmptyLocalBinds + | otherwise + = 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') } @@ -340,36 +462,47 @@ cvtl e = wrapL (cvt e) cvt (AppE x y) = do { x' <- cvtl x; y' <- cvtl y; return $ HsApp x' y' } cvt (LamE ps e) = do { ps' <- cvtPats ps; e' <- cvtl e ; return $ HsLam (mkMatchGroup [mkSimpleMatch ps' e']) } - cvt (TupE [e]) = cvt e - cvt (TupE es) = do { es' <- mapM cvtl es; return $ ExplicitTuple es' Boxed } + cvt (TupE [e]) = cvt e -- Singleton tuples treated like nothing (just parens) + cvt (TupE es) = do { es' <- mapM cvtl es; return $ ExplicitTuple (map Present 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 (CaseE e ms) = do { e' <- cvtl e; ms' <- mapM cvtMatch ms + 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 ; return $ HsCase e' (mkMatchGroup ms') } 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' } cvt (InfixE Nothing s (Just y)) = do { s' <- cvtl s; y' <- cvtl y - ; return $ SectionR s' y' } + ; sec <- returnL $ SectionR s' y' + ; return $ HsPar sec } cvt (InfixE (Just x) s Nothing ) = do { x' <- cvtl x; s' <- cvtl s - ; return $ SectionL x' s' } + ; sec <- returnL $ SectionL x' s' + ; return $ HsPar sec } cvt (InfixE Nothing s Nothing ) = cvt s -- Can I indicate this is an infix thing? cvt (SigE e t) = do { e' <- cvtl e; t' <- cvtType t ; return $ ExprWithTySig e' t' } cvt (RecConE c flds) = do { c' <- cNameL c ; flds' <- mapM cvtFld flds - ; return $ RecordCon c' noPostTcExpr flds' } + ; return $ RecordCon c' noPostTcExpr (HsRecFields flds' Nothing)} cvt (RecUpdE e flds) = do { e' <- cvtl e ; flds' <- mapM cvtFld flds - ; return $ RecordUpd e' flds' placeHolderType placeHolderType } + ; return $ RecordUpd e' (HsRecFields flds' Nothing) [] [] [] } -cvtFld (v,e) = do { v' <- vNameL v; e' <- cvtl e; return (v',e') } +cvtFld :: (TH.Name, TH.Exp) -> CvtM (HsRecField RdrName (LHsExpr RdrName)) +cvtFld (v,e) + = do { v' <- vNameL v; e' <- cvtl e + ; return (HsRecField { hsRecFieldId = v', hsRecFieldArg = e', hsRecPun = False}) } cvtDD :: Range -> CvtM (ArithSeqInfo RdrName) cvtDD (FromR x) = do { x' <- cvtl x; return $ From x' } @@ -381,18 +514,28 @@ cvtDD (FromThenToR x y z) = do { x' <- cvtl x; y' <- cvtl y; z' <- cvtl z; retur -- Do notation and statements ------------------------------------- +cvtHsDo :: HsStmtContext Name.Name -> [TH.Stmt] -> CvtM (HsExpr RdrName) 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 + ; body <- case last stmts' of + L _ (ExprStmt body _ _) -> return body + stmt' -> failWith (bad_last stmt') ; return $ HsDo do_or_lc (init stmts') body void } - + where + bad_last stmt = vcat [ ptext (sLit "Illegal last statement of") <+> pprStmtContext 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.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' } where cvt_one ds = do { ds' <- cvtStmts ds; return (ds', undefined) } @@ -401,7 +544,7 @@ 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] @@ -410,23 +553,62 @@ cvtGuard (NormalB e) = do { e' <- cvtl e; g' <- returnL $ GRHS [] e'; retur cvtpair :: (TH.Guard, TH.Exp) -> CvtM (LGRHS RdrName) cvtpair (NormalG ge,rhs) = do { ge' <- cvtl ge; rhs' <- cvtl rhs - ; g' <- returnL $ mkBindStmt truePat ge' + ; g' <- returnL $ mkExprStmt ge' ; returnL $ GRHS [g'] rhs' } cvtpair (PatG gs,rhs) = do { gs' <- cvtStmts gs; rhs' <- cvtl rhs ; returnL $ GRHS gs' rhs' } cvtOverLit :: Lit -> CvtM (HsOverLit RdrName) -cvtOverLit (IntegerL i) = do { force i; return $ mkHsIntegral i } -cvtOverLit (RationalL r) = do { force r; return $ mkHsFractional r } --- An Integer is like an an (overloaded) '3' in a Haskell source program +cvtOverLit (IntegerL i) + = do { force i; return $ mkHsIntegral i placeHolderType} +cvtOverLit (RationalL r) + = do { force r; return $ mkHsFractional r placeHolderType} +cvtOverLit (StringL s) + = do { let { s' = mkFastString s } + ; force s' + ; return $ mkHsIsString s' placeHolderType + } +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 (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 @@ -448,54 +630,100 @@ cvtp (ConP s ps) = do { s' <- cNameL s; ps' <- cvtPats ps; return $ ConPatI 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 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' } -cvtPatFld (s,p) = do { s' <- vNameL s; p' <- cvtPat p; return (mkRecField s' p') } +cvtPatFld :: (TH.Name, TH.Pat) -> CvtM (HsRecField RdrName (LPat RdrName)) +cvtPatFld (s,p) + = do { s' <- vNameL s; p' <- cvtPat p + ; return (HsRecField { hsRecFieldId = s', hsRecFieldArg = p', hsRecPun = False}) } ----------------------------------------------------------- -- Types and type variables -cvtTvs :: [TH.Name] -> CvtM [LHsTyVarBndr RdrName] +cvtTvs :: [TH.TyVarBndr] -> CvtM [LHsTyVarBndr RdrName] cvtTvs tvs = mapM cvt_tv tvs -cvt_tv tv = do { tv' <- tName tv; returnL $ UserTyVar tv' } - -cvtContext :: Cxt -> CvtM (LHsContext RdrName) +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 :: 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' } - other -> 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, tys') <- split_ty_app ty - ; case head of - TupleT n | length tys' == n -> returnL (HsTupleTy Boxed tys') - | n == 0 -> mk_apps (HsTyVar (getRdrName unitTyCon)) tys' - | otherwise -> mk_apps (HsTyVar (getRdrName (tupleTyCon Boxed n))) tys' - ArrowT | [x',y'] <- tys' -> returnL (HsFunTy x' y') - ListT | [x'] <- tys' -> returnL (HsListTy x') - 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' } - otherwise -> 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' + 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 [] = returnL head - mk_apps head (ty:tys) = do { head' <- returnL head; mk_apps (HsAppTy head' ty) tys } + mk_apps head_ty [] = returnL head_ty + mk_apps head_ty (ty:tys) = do { head_ty' <- returnL head_ty + ; mk_apps (HsAppTy head_ty' ty) tys } split_ty_app :: TH.Type -> CvtM (TH.Type, [LHsType RdrName]) split_ty_app ty = go ty [] @@ -503,19 +731,21 @@ 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) + ----------------------------------------------------------- ----------------------------------------------------------- -- some useful things -truePat = nlConPat (getRdrName trueDataCon) [] - overloadedLit :: Lit -> Bool -- True for literals that Haskell treats as overloaded -overloadedLit (IntegerL l) = True -overloadedLit (RationalL l) = True -overloadedLit l = False +overloadedLit (IntegerL _) = True +overloadedLit (RationalL _) = True +overloadedLit _ = False void :: Type.Type void = placeHolderType @@ -545,20 +775,29 @@ 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 okOcc ns str@(c:_) - | OccName.isVarName ns = startsVarId c || startsVarSym c - | otherwise = startsConId c || startsConSym c || str == "[]" + | 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 - <+> ptext SLIT("name:") <+> quotes (text occ) + = ptext (sLit "Illegal") <+> pprNameSpace ctxt_ns + <+> ptext (sLit "name:") <+> quotes (text occ) thRdrName :: OccName.NameSpace -> String -> TH.NameFlavour -> RdrName -- This turns a Name into a RdrName @@ -571,14 +810,29 @@ thRdrName :: OccName.NameSpace -> String -> TH.NameFlavour -> RdrName -- which will give confusing error messages later -- -- The strict applications ensure that any buried exceptions get forced -thRdrName ctxt_ns occ (TH.NameG th_ns pkg mod) = (mkOrig $! (mkModule (mk_pkg pkg) (mk_mod mod))) $! (mk_occ (mk_ghc_ns th_ns) occ) -thRdrName ctxt_ns occ (TH.NameL uniq) = nameRdrName $! (((Name.mkInternalName $! (mk_uniq uniq)) $! (mk_occ ctxt_ns occ)) noSrcLoc) +thRdrName _ occ (TH.NameG th_ns pkg mod) = thOrigRdrName occ th_ns pkg mod +thRdrName ctxt_ns occ (TH.NameL uniq) = nameRdrName $! (((Name.mkInternalName $! (mk_uniq uniq)) $! (mk_occ ctxt_ns occ)) noSrcSpan) thRdrName ctxt_ns occ (TH.NameQ mod) = (mkRdrQual $! (mk_mod mod)) $! (mk_occ ctxt_ns occ) thRdrName ctxt_ns occ (TH.NameU uniq) = mkRdrUnqual $! (mk_uniq_occ ctxt_ns occ uniq) thRdrName ctxt_ns occ TH.NameS | Just name <- isBuiltInOcc ctxt_ns occ = nameRdrName $! name | otherwise = mkRdrUnqual $! (mk_occ ctxt_ns occ) +thOrigRdrName :: String -> TH.NameSpace -> PkgName -> ModName -> RdrName +thOrigRdrName occ th_ns pkg mod = (mkOrig $! (mkModule (mk_pkg pkg) (mk_mod mod))) $! (mk_occ (mk_ghc_ns th_ns) occ) + +thRdrNameGuesses :: TH.Name -> [RdrName] +thRdrNameGuesses (TH.Name occ flavour) + -- This special case for NameG ensures that we don't generate duplicates in the output list + | TH.NameG th_ns pkg mod <- flavour = [thOrigRdrName occ_str th_ns pkg mod] + | otherwise = [ thRdrName gns occ_str flavour + | gns <- guessed_nss] + where + -- 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 + isBuiltInOcc :: OccName.NameSpace -> String -> Maybe Name.Name -- Built in syntax isn't "in scope" so an Unqual RdrName won't do -- We must generate an Exact name, just as the parser does @@ -588,27 +842,20 @@ isBuiltInOcc ctxt_ns occ "[]" -> Just (Name.getName nilDataCon) "()" -> Just (tup_name 0) '(' : ',' : rest -> go_tuple 2 rest - other -> Nothing + _ -> Nothing where go_tuple n ")" = Just (tup_name n) go_tuple n (',' : rest) = go_tuple (n+1) rest - go_tuple n other = Nothing + go_tuple _ _ = Nothing tup_name n - | OccName.isTcClsName ctxt_ns = Name.getName (tupleTyCon Boxed n) - | otherwise = Name.getName (tupleCon Boxed n) + | OccName.isTcClsNameSpace ctxt_ns = Name.getName (tupleTyCon Boxed n) + | otherwise = Name.getName (tupleCon Boxed n) 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 @@ -622,10 +869,24 @@ 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.