2 % (c) The University of Glasgow 2006
3 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
6 This module converts Template Haskell syntax into HsSyn
10 -- The above warning supression flag is a temporary kludge.
11 -- While working on this module you are encouraged to remove it and fix
12 -- any warnings in the module. See
13 -- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
16 module Convert( convertToHsExpr, convertToHsDecls,
17 convertToHsType, thRdrName ) where
19 #include "HsVersions.h"
22 import qualified Class
27 import qualified OccName
43 import Language.Haskell.TH as TH hiding (sigP)
44 import Language.Haskell.TH.Syntax as TH
48 -------------------------------------------------------------------
49 -- The external interface
51 convertToHsDecls :: SrcSpan -> [TH.Dec] -> Either Message [LHsDecl RdrName]
52 convertToHsDecls loc ds = initCvt loc (mapM cvtTop ds)
54 convertToHsExpr :: SrcSpan -> TH.Exp -> Either Message (LHsExpr RdrName)
56 = case initCvt loc (cvtl e) of
57 Left msg -> Left (msg $$ (ptext SLIT("When converting TH expression")
59 Right res -> Right res
61 convertToHsType :: SrcSpan -> TH.Type -> Either Message (LHsType RdrName)
62 convertToHsType loc t = initCvt loc (cvtType t)
65 -------------------------------------------------------------------
66 newtype CvtM a = CvtM { unCvtM :: SrcSpan -> Either Message a }
67 -- Push down the source location;
68 -- Can fail, with a single error message
70 -- NB: If the conversion succeeds with (Right x), there should
71 -- be no exception values hiding in x
72 -- Reason: so a (head []) in TH code doesn't subsequently
73 -- make GHC crash when it tries to walk the generated tree
75 -- Use the loc everywhere, for lack of anything better
76 -- In particular, we want it on binding locations, so that variables bound in
77 -- the spliced-in declarations get a location that at least relates to the splice point
79 instance Monad CvtM where
80 return x = CvtM $ \loc -> Right x
81 (CvtM m) >>= k = CvtM $ \loc -> case m loc of
83 Right v -> unCvtM (k v) loc
85 initCvt :: SrcSpan -> CvtM a -> Either Message a
86 initCvt loc (CvtM m) = m loc
89 force a = a `seq` return a
91 failWith :: Message -> CvtM a
92 failWith m = CvtM (\loc -> Left full_msg)
94 full_msg = m $$ ptext SLIT("When splicing generated code into the program")
96 returnL :: a -> CvtM (Located a)
97 returnL x = CvtM (\loc -> Right (L loc x))
99 wrapL :: CvtM a -> CvtM (Located a)
100 wrapL (CvtM m) = CvtM (\loc -> case m loc of
102 Right v -> Right (L loc v))
104 -------------------------------------------------------------------
105 cvtTop :: TH.Dec -> CvtM (LHsDecl RdrName)
106 cvtTop d@(TH.ValD _ _ _) = do { L loc d' <- cvtBind d; return (L loc $ Hs.ValD d') }
107 cvtTop d@(TH.FunD _ _) = do { L loc d' <- cvtBind d; return (L loc $ Hs.ValD d') }
108 cvtTop (TH.SigD nm typ) = do { nm' <- vNameL nm
110 ; returnL $ Hs.SigD (TypeSig nm' ty') }
112 cvtTop (TySynD tc tvs rhs)
113 = do { tc' <- tconNameL tc
115 ; rhs' <- cvtType rhs
116 ; returnL $ TyClD (TySynonym tc' tvs' Nothing rhs') }
118 cvtTop (DataD ctxt tc tvs constrs derivs)
119 = do { stuff <- cvt_tycl_hdr ctxt tc tvs
120 ; cons' <- mapM cvtConstr constrs
121 ; derivs' <- cvtDerivs derivs
122 ; returnL $ TyClD (mkTyData DataType stuff Nothing cons' derivs') }
125 cvtTop (NewtypeD ctxt tc tvs constr derivs)
126 = do { stuff <- cvt_tycl_hdr ctxt tc tvs
127 ; con' <- cvtConstr constr
128 ; derivs' <- cvtDerivs derivs
129 ; returnL $ TyClD (mkTyData NewType stuff Nothing [con'] derivs') }
131 cvtTop (ClassD ctxt cl tvs fds decs)
132 = do { (cxt', tc', tvs', _) <- cvt_tycl_hdr ctxt cl tvs
133 ; fds' <- mapM cvt_fundep fds
134 ; (binds', sigs') <- cvtBindsAndSigs decs
135 ; returnL $ TyClD $ mkClassDecl (cxt', tc', tvs') fds' sigs' binds' [] []
136 -- no ATs or docs in TH ^^ ^^
139 cvtTop (InstanceD tys ty decs)
140 = do { (binds', sigs') <- cvtBindsAndSigs decs
141 ; ctxt' <- cvtContext tys
142 ; L loc pred' <- cvtPred ty
143 ; inst_ty' <- returnL $ mkImplicitHsForAllTy ctxt' (L loc (HsPredTy pred'))
144 ; returnL $ InstD (InstDecl inst_ty' binds' sigs' [])
148 cvtTop (ForeignD ford) = do { ford' <- cvtForD ford; returnL $ ForD ford' }
150 cvt_tycl_hdr cxt tc tvs
151 = do { cxt' <- cvtContext cxt
152 ; tc' <- tconNameL tc
154 ; return (cxt', tc', tvs', Nothing) }
156 ---------------------------------------------------
158 -- Can't handle GADTs yet
159 ---------------------------------------------------
161 cvtConstr (NormalC c strtys)
162 = do { c' <- cNameL c
164 ; tys' <- mapM cvt_arg strtys
165 ; returnL $ ConDecl c' Explicit noExistentials cxt' (PrefixCon tys') ResTyH98 Nothing }
167 cvtConstr (RecC c varstrtys)
168 = do { c' <- cNameL c
170 ; args' <- mapM cvt_id_arg varstrtys
171 ; returnL $ ConDecl c' Explicit noExistentials cxt' (RecCon args') ResTyH98 Nothing }
173 cvtConstr (InfixC st1 c st2)
174 = do { c' <- cNameL c
176 ; st1' <- cvt_arg st1
177 ; st2' <- cvt_arg st2
178 ; returnL $ ConDecl c' Explicit noExistentials cxt' (InfixCon st1' st2') ResTyH98 Nothing }
180 cvtConstr (ForallC tvs ctxt (ForallC tvs' ctxt' con'))
181 = cvtConstr (ForallC (tvs ++ tvs') (ctxt ++ ctxt') con')
183 cvtConstr (ForallC tvs ctxt con)
184 = do { L _ con' <- cvtConstr con
186 ; ctxt' <- cvtContext ctxt
188 ConDecl l _ [] (L _ []) x ResTyH98 _
189 -> returnL $ ConDecl l Explicit tvs' ctxt' x ResTyH98 Nothing
190 c -> panic "ForallC: Can't happen" }
192 cvt_arg (IsStrict, ty) = do { ty' <- cvtType ty; returnL $ HsBangTy HsStrict ty' }
193 cvt_arg (NotStrict, ty) = cvtType ty
195 cvt_id_arg (i, str, ty)
196 = do { i' <- vNameL i
197 ; ty' <- cvt_arg (str,ty)
198 ; return (ConDeclField { cd_fld_name = i', cd_fld_type = ty', cd_fld_doc = Nothing}) }
200 cvtDerivs [] = return Nothing
201 cvtDerivs cs = do { cs' <- mapM cvt_one cs
202 ; return (Just cs') }
204 cvt_one c = do { c' <- tconName c
205 ; returnL $ HsPredTy $ HsClassP c' [] }
207 cvt_fundep :: FunDep -> CvtM (Located (Class.FunDep RdrName))
208 cvt_fundep (FunDep xs ys) = do { xs' <- mapM tName xs; ys' <- mapM tName ys; returnL (xs', ys') }
212 ------------------------------------------
213 -- Foreign declarations
214 ------------------------------------------
216 cvtForD :: Foreign -> CvtM (ForeignDecl RdrName)
217 cvtForD (ImportF callconv safety from nm ty)
218 | Just (c_header, cis) <- parse_ccall_impent (TH.nameBase nm) from
219 = do { nm' <- vNameL nm
221 ; let i = CImport (cvt_conv callconv) safety' c_header nilFS cis
222 ; return $ ForeignImport nm' ty' i }
225 = failWith $ text (show from)<+> ptext SLIT("is not a valid ccall impent")
227 safety' = case safety of
229 Safe -> PlaySafe False
230 Threadsafe -> PlaySafe True
232 cvtForD (ExportF callconv as nm ty)
233 = do { nm' <- vNameL nm
235 ; let e = CExport (CExportStatic (mkFastString as) (cvt_conv callconv))
236 ; return $ ForeignExport nm' ty' e }
238 cvt_conv TH.CCall = CCallConv
239 cvt_conv TH.StdCall = StdCallConv
241 parse_ccall_impent :: String -> String -> Maybe (FastString, CImportSpec)
242 parse_ccall_impent nm s
243 = case lex_ccall_impent s of
244 Just ["dynamic"] -> Just (nilFS, CFunction DynamicTarget)
245 Just ["wrapper"] -> Just (nilFS, CWrapper)
246 Just ("static":ts) -> parse_ccall_impent_static nm ts
247 Just ts -> parse_ccall_impent_static nm ts
250 parse_ccall_impent_static :: String
252 -> Maybe (FastString, CImportSpec)
253 parse_ccall_impent_static nm ts
254 = let ts' = case ts of
255 [ "&", cid] -> [ cid]
256 [fname, "&" ] -> [fname ]
257 [fname, "&", cid] -> [fname, cid]
260 [ cid] | is_cid cid -> Just (nilFS, mk_cid cid)
261 [fname, cid] | is_cid cid -> Just (mkFastString fname, mk_cid cid)
262 [ ] -> Just (nilFS, mk_cid nm)
263 [fname ] -> Just (mkFastString fname, mk_cid nm)
265 where is_cid :: String -> Bool
266 is_cid x = all (/= '.') x && (isAlpha (head x) || head x == '_')
267 mk_cid :: String -> CImportSpec
268 mk_cid = CFunction . StaticTarget . mkFastString
270 lex_ccall_impent :: String -> Maybe [String]
271 lex_ccall_impent "" = Just []
272 lex_ccall_impent ('&':xs) = fmap ("&":) $ lex_ccall_impent xs
273 lex_ccall_impent (' ':xs) = lex_ccall_impent xs
274 lex_ccall_impent ('\t':xs) = lex_ccall_impent xs
275 lex_ccall_impent xs = case span is_valid xs of
277 (t, xs') -> fmap (t:) $ lex_ccall_impent xs'
278 where is_valid :: Char -> Bool
279 is_valid c = isAscii c && (isAlphaNum c || c `elem` "._")
282 ---------------------------------------------------
284 ---------------------------------------------------
286 cvtDecs :: [TH.Dec] -> CvtM (HsLocalBinds RdrName)
287 cvtDecs [] = return EmptyLocalBinds
288 cvtDecs ds = do { (binds,sigs) <- cvtBindsAndSigs ds
289 ; return (HsValBinds (ValBindsIn binds sigs)) }
292 = do { binds' <- mapM cvtBind binds; sigs' <- mapM cvtSig sigs
293 ; return (listToBag binds', sigs') }
295 (sigs, binds) = partition is_sig ds
297 is_sig (TH.SigD _ _) = True
300 cvtSig (TH.SigD nm ty)
301 = do { nm' <- vNameL nm; ty' <- cvtType ty; returnL (Hs.TypeSig nm' ty') }
303 cvtBind :: TH.Dec -> CvtM (LHsBind RdrName)
304 -- Used only for declarations in a 'let/where' clause,
305 -- not for top level decls
306 cvtBind (TH.ValD (TH.VarP s) body ds)
307 = do { s' <- vNameL s
308 ; cl' <- cvtClause (Clause [] body ds)
309 ; returnL $ mkFunBind s' [cl'] }
311 cvtBind (TH.FunD nm cls)
312 = do { nm' <- vNameL nm
313 ; cls' <- mapM cvtClause cls
314 ; returnL $ mkFunBind nm' cls' }
316 cvtBind (TH.ValD p body ds)
317 = do { p' <- cvtPat p
318 ; g' <- cvtGuard body
320 ; returnL $ PatBind { pat_lhs = p', pat_rhs = GRHSs g' ds',
321 pat_rhs_ty = void, bind_fvs = placeHolderNames } }
324 = failWith (sep [ptext SLIT("Illegal kind of declaration in where clause"),
325 nest 2 (text (TH.pprint d))])
327 cvtClause :: TH.Clause -> CvtM (Hs.LMatch RdrName)
328 cvtClause (Clause ps body wheres)
329 = do { ps' <- cvtPats ps
330 ; g' <- cvtGuard body
331 ; ds' <- cvtDecs wheres
332 ; returnL $ Hs.Match ps' Nothing (GRHSs g' ds') }
335 -------------------------------------------------------------------
337 -------------------------------------------------------------------
339 cvtl :: TH.Exp -> CvtM (LHsExpr RdrName)
340 cvtl e = wrapL (cvt e)
342 cvt (VarE s) = do { s' <- vName s; return $ HsVar s' }
343 cvt (ConE s) = do { s' <- cName s; return $ HsVar s' }
345 | overloadedLit l = do { l' <- cvtOverLit l; return $ HsOverLit l' }
346 | otherwise = do { l' <- cvtLit l; return $ HsLit l' }
348 cvt (AppE x y) = do { x' <- cvtl x; y' <- cvtl y; return $ HsApp x' y' }
349 cvt (LamE ps e) = do { ps' <- cvtPats ps; e' <- cvtl e
350 ; return $ HsLam (mkMatchGroup [mkSimpleMatch ps' e']) }
351 cvt (TupE [e]) = cvt e
352 cvt (TupE es) = do { es' <- mapM cvtl es; return $ ExplicitTuple es' Boxed }
353 cvt (CondE x y z) = do { x' <- cvtl x; y' <- cvtl y; z' <- cvtl z
354 ; return $ HsIf x' y' z' }
355 cvt (LetE ds e) = do { ds' <- cvtDecs ds; e' <- cvtl e; return $ HsLet ds' e' }
356 cvt (CaseE e ms) = do { e' <- cvtl e; ms' <- mapM cvtMatch ms
357 ; return $ HsCase e' (mkMatchGroup ms') }
358 cvt (DoE ss) = cvtHsDo DoExpr ss
359 cvt (CompE ss) = cvtHsDo ListComp ss
360 cvt (ArithSeqE dd) = do { dd' <- cvtDD dd; return $ ArithSeq noPostTcExpr dd' }
361 cvt (ListE xs) = do { xs' <- mapM cvtl xs; return $ ExplicitList void xs' }
362 cvt (InfixE (Just x) s (Just y)) = do { x' <- cvtl x; s' <- cvtl s; y' <- cvtl y
363 ; e' <- returnL $ OpApp x' s' undefined y'
364 ; return $ HsPar e' }
365 cvt (InfixE Nothing s (Just y)) = do { s' <- cvtl s; y' <- cvtl y
366 ; return $ SectionR s' y' }
367 cvt (InfixE (Just x) s Nothing ) = do { x' <- cvtl x; s' <- cvtl s
368 ; return $ SectionL x' s' }
369 cvt (InfixE Nothing s Nothing ) = cvt s -- Can I indicate this is an infix thing?
371 cvt (SigE e t) = do { e' <- cvtl e; t' <- cvtType t
372 ; return $ ExprWithTySig e' t' }
373 cvt (RecConE c flds) = do { c' <- cNameL c
374 ; flds' <- mapM cvtFld flds
375 ; return $ RecordCon c' noPostTcExpr (HsRecFields flds' Nothing)}
376 cvt (RecUpdE e flds) = do { e' <- cvtl e
377 ; flds' <- mapM cvtFld flds
378 ; return $ RecordUpd e' (HsRecFields flds' Nothing) [] [] [] }
381 = do { v' <- vNameL v; e' <- cvtl e
382 ; return (HsRecField { hsRecFieldId = v', hsRecFieldArg = e', hsRecPun = False}) }
384 cvtDD :: Range -> CvtM (ArithSeqInfo RdrName)
385 cvtDD (FromR x) = do { x' <- cvtl x; return $ From x' }
386 cvtDD (FromThenR x y) = do { x' <- cvtl x; y' <- cvtl y; return $ FromThen x' y' }
387 cvtDD (FromToR x y) = do { x' <- cvtl x; y' <- cvtl y; return $ FromTo x' y' }
388 cvtDD (FromThenToR x y z) = do { x' <- cvtl x; y' <- cvtl y; z' <- cvtl z; return $ FromThenTo x' y' z' }
390 -------------------------------------
391 -- Do notation and statements
392 -------------------------------------
394 cvtHsDo do_or_lc stmts
395 = do { stmts' <- cvtStmts stmts
396 ; let body = case last stmts' of
397 L _ (ExprStmt body _ _) -> body
398 ; return $ HsDo do_or_lc (init stmts') body void }
400 cvtStmts = mapM cvtStmt
402 cvtStmt :: TH.Stmt -> CvtM (Hs.LStmt RdrName)
403 cvtStmt (NoBindS e) = do { e' <- cvtl e; returnL $ mkExprStmt e' }
404 cvtStmt (TH.BindS p e) = do { p' <- cvtPat p; e' <- cvtl e; returnL $ mkBindStmt p' e' }
405 cvtStmt (TH.LetS ds) = do { ds' <- cvtDecs ds; returnL $ LetStmt ds' }
406 cvtStmt (TH.ParS dss) = do { dss' <- mapM cvt_one dss; returnL $ ParStmt dss' }
408 cvt_one ds = do { ds' <- cvtStmts ds; return (ds', undefined) }
410 cvtMatch :: TH.Match -> CvtM (Hs.LMatch RdrName)
411 cvtMatch (TH.Match p body decs)
412 = do { p' <- cvtPat p
413 ; g' <- cvtGuard body
414 ; decs' <- cvtDecs decs
415 ; returnL $ Hs.Match [p'] Nothing (GRHSs g' decs') }
417 cvtGuard :: TH.Body -> CvtM [LGRHS RdrName]
418 cvtGuard (GuardedB pairs) = mapM cvtpair pairs
419 cvtGuard (NormalB e) = do { e' <- cvtl e; g' <- returnL $ GRHS [] e'; return [g'] }
421 cvtpair :: (TH.Guard, TH.Exp) -> CvtM (LGRHS RdrName)
422 cvtpair (NormalG ge,rhs) = do { ge' <- cvtl ge; rhs' <- cvtl rhs
423 ; g' <- returnL $ mkBindStmt truePat ge'
424 ; returnL $ GRHS [g'] rhs' }
425 cvtpair (PatG gs,rhs) = do { gs' <- cvtStmts gs; rhs' <- cvtl rhs
426 ; returnL $ GRHS gs' rhs' }
428 cvtOverLit :: Lit -> CvtM (HsOverLit RdrName)
429 cvtOverLit (IntegerL i) = do { force i; return $ mkHsIntegral i placeHolderType}
430 cvtOverLit (RationalL r) = do { force r; return $ mkHsFractional r placeHolderType}
431 cvtOverLit (StringL s) = do { let { s' = mkFastString s }; force s'; return $ mkHsIsString s' placeHolderType }
432 -- An Integer is like an an (overloaded) '3' in a Haskell source program
433 -- Similarly 3.5 for fractionals
435 cvtLit :: Lit -> CvtM HsLit
436 cvtLit (IntPrimL i) = do { force i; return $ HsIntPrim i }
437 cvtLit (FloatPrimL f) = do { force f; return $ HsFloatPrim f }
438 cvtLit (DoublePrimL f) = do { force f; return $ HsDoublePrim f }
439 cvtLit (CharL c) = do { force c; return $ HsChar c }
440 cvtLit (StringL s) = do { let { s' = mkFastString s }; force s'; return $ HsString s' }
442 cvtPats :: [TH.Pat] -> CvtM [Hs.LPat RdrName]
443 cvtPats pats = mapM cvtPat pats
445 cvtPat :: TH.Pat -> CvtM (Hs.LPat RdrName)
446 cvtPat pat = wrapL (cvtp pat)
448 cvtp :: TH.Pat -> CvtM (Hs.Pat RdrName)
450 | overloadedLit l = do { l' <- cvtOverLit l
451 ; return (mkNPat l' Nothing) }
452 -- Not right for negative patterns;
453 -- need to think about that!
454 | otherwise = do { l' <- cvtLit l; return $ Hs.LitPat l' }
455 cvtp (TH.VarP s) = do { s' <- vName s; return $ Hs.VarPat s' }
456 cvtp (TupP [p]) = cvtp p
457 cvtp (TupP ps) = do { ps' <- cvtPats ps; return $ TuplePat ps' Boxed void }
458 cvtp (ConP s ps) = do { s' <- cNameL s; ps' <- cvtPats ps; return $ ConPatIn s' (PrefixCon ps') }
459 cvtp (InfixP p1 s p2) = do { s' <- cNameL s; p1' <- cvtPat p1; p2' <- cvtPat p2
460 ; return $ ConPatIn s' (InfixCon p1' p2') }
461 cvtp (TildeP p) = do { p' <- cvtPat p; return $ LazyPat p' }
462 cvtp (TH.AsP s p) = do { s' <- vNameL s; p' <- cvtPat p; return $ AsPat s' p' }
463 cvtp TH.WildP = return $ WildPat void
464 cvtp (RecP c fs) = do { c' <- cNameL c; fs' <- mapM cvtPatFld fs
465 ; return $ ConPatIn c' $ Hs.RecCon (HsRecFields fs' Nothing) }
466 cvtp (ListP ps) = do { ps' <- cvtPats ps; return $ ListPat ps' void }
467 cvtp (SigP p t) = do { p' <- cvtPat p; t' <- cvtType t; return $ SigPatIn p' t' }
470 = do { s' <- vNameL s; p' <- cvtPat p
471 ; return (HsRecField { hsRecFieldId = s', hsRecFieldArg = p', hsRecPun = False}) }
473 -----------------------------------------------------------
474 -- Types and type variables
476 cvtTvs :: [TH.Name] -> CvtM [LHsTyVarBndr RdrName]
477 cvtTvs tvs = mapM cvt_tv tvs
479 cvt_tv tv = do { tv' <- tName tv; returnL $ UserTyVar tv' }
481 cvtContext :: Cxt -> CvtM (LHsContext RdrName)
482 cvtContext tys = do { preds' <- mapM cvtPred tys; returnL preds' }
484 cvtPred :: TH.Type -> CvtM (LHsPred RdrName)
486 = do { (head, tys') <- split_ty_app ty
488 ConT tc -> do { tc' <- tconName tc; returnL $ HsClassP tc' tys' }
489 VarT tv -> do { tv' <- tName tv; returnL $ HsClassP tv' tys' }
490 other -> failWith (ptext SLIT("Malformed predicate") <+> text (TH.pprint ty)) }
492 cvtType :: TH.Type -> CvtM (LHsType RdrName)
493 cvtType ty = do { (head, tys') <- split_ty_app ty
495 TupleT n | length tys' == n -> returnL (HsTupleTy Boxed tys')
496 | n == 0 -> mk_apps (HsTyVar (getRdrName unitTyCon)) tys'
497 | otherwise -> mk_apps (HsTyVar (getRdrName (tupleTyCon Boxed n))) tys'
498 ArrowT | [x',y'] <- tys' -> returnL (HsFunTy x' y')
499 ListT | [x'] <- tys' -> returnL (HsListTy x')
500 VarT nm -> do { nm' <- tName nm; mk_apps (HsTyVar nm') tys' }
501 ConT nm -> do { nm' <- tconName nm; mk_apps (HsTyVar nm') tys' }
503 ForallT tvs cxt ty | null tys' -> do { tvs' <- cvtTvs tvs
504 ; cxt' <- cvtContext cxt
506 ; returnL $ mkExplicitHsForAllTy tvs' cxt' ty' }
507 otherwise -> failWith (ptext SLIT("Malformed type") <+> text (show ty))
510 mk_apps head [] = returnL head
511 mk_apps head (ty:tys) = do { head' <- returnL head; mk_apps (HsAppTy head' ty) tys }
513 split_ty_app :: TH.Type -> CvtM (TH.Type, [LHsType RdrName])
514 split_ty_app ty = go ty []
516 go (AppT f a) as' = do { a' <- cvtType a; go f (a':as') }
517 go f as = return (f,as)
519 -----------------------------------------------------------
522 -----------------------------------------------------------
523 -- some useful things
525 truePat = nlConPat (getRdrName trueDataCon) []
527 overloadedLit :: Lit -> Bool
528 -- True for literals that Haskell treats as overloaded
529 overloadedLit (IntegerL l) = True
530 overloadedLit (RationalL l) = True
531 overloadedLit l = False
534 void = placeHolderType
536 --------------------------------------------------------------------
537 -- Turning Name back into RdrName
538 --------------------------------------------------------------------
541 vNameL, cNameL, tconNameL :: TH.Name -> CvtM (Located RdrName)
542 vName, cName, tName, tconName :: TH.Name -> CvtM RdrName
544 vNameL n = wrapL (vName n)
545 vName n = cvtName OccName.varName n
547 -- Constructor function names; this is Haskell source, hence srcDataName
548 cNameL n = wrapL (cName n)
549 cName n = cvtName OccName.dataName n
551 -- Type variable names
552 tName n = cvtName OccName.tvName n
554 -- Type Constructor names
555 tconNameL n = wrapL (tconName n)
556 tconName n = cvtName OccName.tcClsName n
558 cvtName :: OccName.NameSpace -> TH.Name -> CvtM RdrName
559 cvtName ctxt_ns (TH.Name occ flavour)
560 | not (okOcc ctxt_ns occ_str) = failWith (badOcc ctxt_ns occ_str)
561 | otherwise = force (thRdrName ctxt_ns occ_str flavour)
563 occ_str = TH.occString occ
565 okOcc :: OccName.NameSpace -> String -> Bool
568 | OccName.isVarName ns = startsVarId c || startsVarSym c
569 | otherwise = startsConId c || startsConSym c || str == "[]"
571 badOcc :: OccName.NameSpace -> String -> SDoc
573 = ptext SLIT("Illegal") <+> pprNameSpace ctxt_ns
574 <+> ptext SLIT("name:") <+> quotes (text occ)
576 thRdrName :: OccName.NameSpace -> String -> TH.NameFlavour -> RdrName
577 -- This turns a Name into a RdrName
578 -- The passed-in name space tells what the context is expecting;
579 -- use it unless the TH name knows what name-space it comes
580 -- from, in which case use the latter
582 -- ToDo: we may generate silly RdrNames, by passing a name space
583 -- that doesn't match the string, like VarName ":+",
584 -- which will give confusing error messages later
586 -- The strict applications ensure that any buried exceptions get forced
587 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)
588 thRdrName ctxt_ns occ (TH.NameL uniq) = nameRdrName $! (((Name.mkInternalName $! (mk_uniq uniq)) $! (mk_occ ctxt_ns occ)) noSrcSpan)
589 thRdrName ctxt_ns occ (TH.NameQ mod) = (mkRdrQual $! (mk_mod mod)) $! (mk_occ ctxt_ns occ)
590 thRdrName ctxt_ns occ (TH.NameU uniq) = mkRdrUnqual $! (mk_uniq_occ ctxt_ns occ uniq)
591 thRdrName ctxt_ns occ TH.NameS
592 | Just name <- isBuiltInOcc ctxt_ns occ = nameRdrName $! name
593 | otherwise = mkRdrUnqual $! (mk_occ ctxt_ns occ)
595 isBuiltInOcc :: OccName.NameSpace -> String -> Maybe Name.Name
596 -- Built in syntax isn't "in scope" so an Unqual RdrName won't do
597 -- We must generate an Exact name, just as the parser does
598 isBuiltInOcc ctxt_ns occ
600 ":" -> Just (Name.getName consDataCon)
601 "[]" -> Just (Name.getName nilDataCon)
602 "()" -> Just (tup_name 0)
603 '(' : ',' : rest -> go_tuple 2 rest
606 go_tuple n ")" = Just (tup_name n)
607 go_tuple n (',' : rest) = go_tuple (n+1) rest
608 go_tuple n other = Nothing
611 | OccName.isTcClsName ctxt_ns = Name.getName (tupleTyCon Boxed n)
612 | otherwise = Name.getName (tupleCon Boxed n)
614 mk_uniq_occ :: OccName.NameSpace -> String -> Int# -> OccName.OccName
615 mk_uniq_occ ns occ uniq
616 = OccName.mkOccName ns (occ ++ '[' : shows (mk_uniq uniq) "]")
617 -- The idea here is to make a name that
618 -- a) the user could not possibly write, and
619 -- b) cannot clash with another NameU
620 -- Previously I generated an Exact RdrName with mkInternalName.
621 -- This works fine for local binders, but does not work at all for
622 -- top-level binders, which must have External Names, since they are
623 -- rapidly baked into data constructors and the like. Baling out
624 -- and generating an unqualified RdrName here is the simple solution
626 -- The packing and unpacking is rather turgid :-(
627 mk_occ :: OccName.NameSpace -> String -> OccName.OccName
628 mk_occ ns occ = OccName.mkOccNameFS ns (mkFastString occ)
630 mk_ghc_ns :: TH.NameSpace -> OccName.NameSpace
631 mk_ghc_ns TH.DataName = OccName.dataName
632 mk_ghc_ns TH.TcClsName = OccName.tcClsName
633 mk_ghc_ns TH.VarName = OccName.varName
635 mk_mod :: TH.ModName -> ModuleName
636 mk_mod mod = mkModuleName (TH.modString mod)
638 mk_pkg :: TH.ModName -> PackageId
639 mk_pkg pkg = stringToPackageId (TH.pkgString pkg)
641 mk_uniq :: Int# -> Unique
642 mk_uniq u = mkUniqueGrimily (I# u)