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Diffstat (limited to 'compiler/hsSyn/Convert.lhs')
| -rw-r--r-- | compiler/hsSyn/Convert.lhs | 622 |
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diff --git a/compiler/hsSyn/Convert.lhs b/compiler/hsSyn/Convert.lhs new file mode 100644 index 0000000000..6c14c11893 --- /dev/null +++ b/compiler/hsSyn/Convert.lhs @@ -0,0 +1,622 @@ +% +% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 +% + +This module converts Template Haskell syntax into HsSyn + + +\begin{code} +module Convert( convertToHsExpr, convertToHsDecls, convertToHsType, thRdrName ) where + +#include "HsVersions.h" + +import Language.Haskell.TH as TH hiding (sigP) +import Language.Haskell.TH.Syntax as TH + +import HsSyn as Hs +import qualified Class (FunDep) +import RdrName ( RdrName, mkRdrUnqual, mkRdrQual, mkOrig, getRdrName, nameRdrName ) +import qualified Name ( Name, mkInternalName, getName ) +import Module ( Module, mkModule ) +import RdrHsSyn ( mkClassDecl, mkTyData ) +import qualified OccName +import OccName ( startsVarId, startsVarSym, startsConId, startsConSym, + pprNameSpace ) +import SrcLoc ( Located(..), SrcSpan ) +import Type ( Type ) +import TysWiredIn ( unitTyCon, tupleTyCon, tupleCon, trueDataCon, nilDataCon, consDataCon ) +import BasicTypes( Boxity(..) ) +import ForeignCall ( Safety(..), CCallConv(..), CCallTarget(..), + CExportSpec(..)) +import Char ( isAscii, isAlphaNum, isAlpha ) +import List ( partition ) +import Unique ( Unique, mkUniqueGrimily ) +import ErrUtils ( Message ) +import GLAEXTS ( Int(..), Int# ) +import SrcLoc ( noSrcLoc ) +import Bag ( listToBag ) +import FastString +import Outputable + + + +------------------------------------------------------------------- +-- The external interface + +convertToHsDecls :: SrcSpan -> [TH.Dec] -> Either Message [LHsDecl RdrName] +convertToHsDecls loc ds = initCvt loc (mapM cvtTop ds) + +convertToHsExpr :: SrcSpan -> TH.Exp -> Either Message (LHsExpr RdrName) +convertToHsExpr loc e = initCvt loc (cvtl e) + +convertToHsType :: SrcSpan -> TH.Type -> Either Message (LHsType RdrName) +convertToHsType loc t = initCvt loc (cvtType t) + + +------------------------------------------------------------------- +newtype CvtM a = CvtM { unCvtM :: SrcSpan -> Either Message a } + -- Push down the source location; + -- Can fail, with a single error message + +-- NB: If the conversion succeeds with (Right x), there should +-- be no exception values hiding in x +-- Reason: so a (head []) in TH code doesn't subsequently +-- make GHC crash when it tries to walk the generated tree + +-- Use the loc everywhere, for lack of anything better +-- In particular, we want it on binding locations, so that variables bound in +-- 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 + (CvtM m) >>= k = CvtM $ \loc -> case m loc of + Left err -> Left err + Right v -> unCvtM (k v) loc + +initCvt :: SrcSpan -> CvtM a -> Either Message a +initCvt loc (CvtM m) = m loc + +force :: a -> CvtM a +force a = a `seq` return a + +failWith :: Message -> CvtM a +failWith m = CvtM (\loc -> Left full_msg) + where + full_msg = m $$ ptext SLIT("When splicing generated code into the program") + +returnL :: a -> CvtM (Located a) +returnL x = CvtM (\loc -> Right (L loc x)) + +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 + ; rhs' <- cvtType rhs + ; returnL $ TyClD (TySynonym tc' tvs' rhs') } + +cvtTop (DataD ctxt tc tvs constrs derivs) + = do { stuff <- cvt_tycl_hdr ctxt tc tvs + ; cons' <- mapM cvtConstr constrs + ; derivs' <- cvtDerivs derivs + ; returnL $ TyClD (mkTyData DataType stuff Nothing cons' derivs') } + + +cvtTop (NewtypeD ctxt tc tvs constr derivs) + = do { stuff <- cvt_tycl_hdr ctxt tc tvs + ; con' <- cvtConstr constr + ; derivs' <- cvtDerivs derivs + ; returnL $ TyClD (mkTyData NewType stuff Nothing [con'] derivs') } + +cvtTop (ClassD ctxt cl tvs fds decs) + = do { stuff <- cvt_tycl_hdr ctxt cl tvs + ; fds' <- mapM cvt_fundep fds + ; (binds', sigs') <- cvtBindsAndSigs decs + ; returnL $ TyClD $ mkClassDecl stuff fds' sigs' binds' } + +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') } + +cvtTop (ForeignD ford) = do { ford' <- cvtForD ford; returnL $ ForD ford' } + +cvt_tycl_hdr cxt tc tvs + = do { cxt' <- cvtContext cxt + ; tc' <- tconNameL tc + ; tvs' <- cvtTvs tvs + ; return (cxt', tc', tvs') } + +--------------------------------------------------- +-- Data types +-- Can't handle GADTs yet +--------------------------------------------------- + +cvtConstr (NormalC c strtys) + = do { c' <- cNameL c + ; cxt' <- returnL [] + ; tys' <- mapM cvt_arg strtys + ; returnL $ ConDecl c' Explicit noExistentials cxt' (PrefixCon tys') ResTyH98 } + +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 } + +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 } + +cvtConstr (ForallC tvs ctxt (ForallC tvs' ctxt' con')) + = cvtConstr (ForallC (tvs ++ tvs') (ctxt ++ ctxt') con') + +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 + c -> panic "ForallC: Can't happen" } + +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 (i', ty') } + +cvtDerivs [] = return Nothing +cvtDerivs cs = do { cs' <- mapM cvt_one cs + ; return (Just cs') } + where + cvt_one c = do { c' <- tconName c + ; returnL $ HsPredTy $ HsClassP c' [] } + +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 = [] + +------------------------------------------ +-- Foreign declarations +------------------------------------------ + +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 False } + + | otherwise + = 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 + +cvtForD (ExportF callconv as nm ty) + = do { nm' <- vNameL nm + ; ty' <- cvtType ty + ; let e = CExport (CExportStatic (mkFastString as) (cvt_conv callconv)) + ; return $ ForeignExport nm' ty' e False } + +cvt_conv CCall = CCallConv +cvt_conv 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 + + is_sig (TH.SigD _ _) = True + is_sig other = False + +cvtSig (TH.SigD nm ty) + = do { nm' <- vNameL nm; ty' <- cvtType ty; returnL (Hs.TypeSig nm' ty') } + +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) + = 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))]) + +cvtClause :: TH.Clause -> CvtM (Hs.LMatch RdrName) +cvtClause (Clause ps body wheres) + = do { ps' <- cvtPats ps + ; g' <- cvtGuard body + ; ds' <- cvtDecs wheres + ; returnL $ Hs.Match ps' Nothing (GRHSs g' ds') } + + +------------------------------------------------------------------- +-- Expressions +------------------------------------------------------------------- + +cvtl :: TH.Exp -> CvtM (LHsExpr RdrName) +cvtl e = wrapL (cvt e) + where + cvt (VarE s) = do { s' <- vName s; return $ HsVar s' } + cvt (ConE s) = do { s' <- cName s; return $ HsVar s' } + cvt (LitE l) + | overloadedLit l = do { l' <- cvtOverLit l; return $ HsOverLit l' } + | otherwise = do { l' <- cvtLit l; return $ HsLit l' } + + 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 (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 + ; 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 (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' } + cvt (InfixE (Just x) s Nothing ) = do { x' <- cvtl x; s' <- cvtl s + ; return $ SectionL x' s' } + 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' } + cvt (RecUpdE e flds) = do { e' <- cvtl e + ; flds' <- mapM cvtFld flds + ; return $ RecordUpd e' flds' placeHolderType placeHolderType } + +cvtFld (v,e) = do { v' <- vNameL v; e' <- cvtl e; return (v',e') } + +cvtDD :: Range -> CvtM (ArithSeqInfo RdrName) +cvtDD (FromR x) = do { x' <- cvtl x; return $ From x' } +cvtDD (FromThenR x y) = do { x' <- cvtl x; y' <- cvtl y; return $ FromThen x' y' } +cvtDD (FromToR x y) = do { x' <- cvtl x; y' <- cvtl y; return $ FromTo x' y' } +cvtDD (FromThenToR x y z) = do { x' <- cvtl x; y' <- cvtl y; z' <- cvtl z; return $ FromThenTo x' y' z' } + +------------------------------------- +-- Do notation and statements +------------------------------------- + +cvtHsDo do_or_lc stmts + = do { stmts' <- cvtStmts stmts + ; let body = case last stmts' of + L _ (ExprStmt body _ _) -> body + ; return $ HsDo do_or_lc (init stmts') body void } + +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' } + where + cvt_one ds = do { ds' <- cvtStmts ds; return (ds', undefined) } + +cvtMatch :: TH.Match -> CvtM (Hs.LMatch RdrName) +cvtMatch (TH.Match p body decs) + = do { p' <- cvtPat p + ; g' <- cvtGuard body + ; decs' <- cvtDecs decs + ; returnL $ Hs.Match [p'] Nothing (GRHSs g' decs') } + +cvtGuard :: TH.Body -> CvtM [LGRHS RdrName] +cvtGuard (GuardedB pairs) = mapM cvtpair pairs +cvtGuard (NormalB e) = do { e' <- cvtl e; g' <- returnL $ GRHS [] e'; return [g'] } + +cvtpair :: (TH.Guard, TH.Exp) -> CvtM (LGRHS RdrName) +cvtpair (NormalG ge,rhs) = do { ge' <- cvtl ge; rhs' <- cvtl rhs + ; g' <- returnL $ mkBindStmt truePat 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 +-- Similarly 3.5 for fractionals + +cvtLit :: Lit -> CvtM HsLit +cvtLit (IntPrimL i) = do { force i; return $ HsIntPrim i } +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' } + +cvtPats :: [TH.Pat] -> CvtM [Hs.LPat RdrName] +cvtPats pats = mapM cvtPat pats + +cvtPat :: TH.Pat -> CvtM (Hs.LPat RdrName) +cvtPat pat = wrapL (cvtp pat) + +cvtp :: TH.Pat -> CvtM (Hs.Pat RdrName) +cvtp (TH.LitP l) + | overloadedLit l = do { l' <- cvtOverLit l + ; return (mkNPat l' Nothing) } + -- Not right for negative patterns; + -- need to think about that! + | otherwise = do { l' <- cvtLit l; return $ Hs.LitPat 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 (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 (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' } +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 (s',p') } + +----------------------------------------------------------- +-- Types and type variables + +cvtTvs :: [TH.Name] -> CvtM [LHsTyVarBndr RdrName] +cvtTvs tvs = mapM cvt_tv tvs + +cvt_tv tv = do { tv' <- tName tv; returnL $ UserTyVar tv' } + +cvtContext :: Cxt -> CvtM (LHsContext RdrName) +cvtContext tys = do { preds' <- mapM cvtPred tys; returnL preds' } + +cvtPred :: TH.Type -> CvtM (LHsPred RdrName) +cvtPred 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)) } + +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)) + } + where + mk_apps head [] = returnL head + mk_apps head (ty:tys) = do { head' <- returnL head; mk_apps (HsAppTy head' ty) tys } + +split_ty_app :: TH.Type -> CvtM (TH.Type, [LHsType RdrName]) +split_ty_app ty = go ty [] + where + go (AppT f a) as' = do { a' <- cvtType a; go f (a':as') } + go f as = return (f,as) + +----------------------------------------------------------- + + +----------------------------------------------------------- +-- 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 + +void :: Type.Type +void = placeHolderType + +-------------------------------------------------------------------- +-- Turning Name back into RdrName +-------------------------------------------------------------------- + +-- variable names +vNameL, cNameL, tconNameL :: TH.Name -> CvtM (Located RdrName) +vName, cName, tName, tconName :: TH.Name -> CvtM RdrName + +vNameL n = wrapL (vName n) +vName n = cvtName OccName.varName n + +-- Constructor function names; this is Haskell source, hence srcDataName +cNameL n = wrapL (cName n) +cName n = cvtName OccName.dataName n + +-- Type variable names +tName n = cvtName OccName.tvName n + +-- Type Constructor names +tconNameL n = wrapL (tconName n) +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) + where + occ_str = TH.occString occ + +okOcc :: OccName.NameSpace -> String -> Bool +okOcc _ [] = False +okOcc ns str@(c:_) + | OccName.isVarName ns = startsVarId c || startsVarSym c + | otherwise = startsConId c || startsConSym c || str == "[]" + +badOcc :: OccName.NameSpace -> String -> SDoc +badOcc ctxt_ns 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 +-- The passed-in name space tells what the context is expecting; +-- use it unless the TH name knows what name-space it comes +-- from, in which case use the latter +-- +-- ToDo: we may generate silly RdrNames, by passing a name space +-- that doesn't match the string, like VarName ":+", +-- 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 mod) = (mkOrig $! (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 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) + +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 +isBuiltInOcc ctxt_ns occ + = case occ of + ":" -> Just (Name.getName consDataCon) + "[]" -> Just (Name.getName nilDataCon) + "()" -> Just (tup_name 0) + '(' : ',' : rest -> go_tuple 2 rest + other -> Nothing + where + go_tuple n ")" = Just (tup_name n) + go_tuple n (',' : rest) = go_tuple (n+1) rest + go_tuple n other = Nothing + + tup_name n + | OccName.isTcClsName 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 + +-- The packing and unpacking is rather turgid :-( +mk_occ :: OccName.NameSpace -> String -> OccName.OccName +mk_occ ns occ = OccName.mkOccNameFS ns (mkFastString occ) + +mk_ghc_ns :: TH.NameSpace -> OccName.NameSpace +mk_ghc_ns TH.DataName = OccName.dataName +mk_ghc_ns TH.TcClsName = OccName.tcClsName +mk_ghc_ns TH.VarName = OccName.varName + +mk_mod :: TH.ModName -> Module +mk_mod mod = mkModule (TH.modString mod) + +mk_uniq :: Int# -> Unique +mk_uniq u = mkUniqueGrimily (I# u) +\end{code} + |