2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
5 This module converts Template Haskell syntax into HsSyn
9 module Convert( convertToHsExpr, convertToHsDecls, convertToHsType, thRdrName ) where
11 #include "HsVersions.h"
13 import Language.Haskell.TH as TH hiding (sigP)
14 import Language.Haskell.TH.Syntax as TH
17 import qualified Class (FunDep)
18 import RdrName ( RdrName, mkRdrUnqual, mkRdrQual, mkOrig, getRdrName, nameRdrName )
19 import qualified Name ( Name, mkInternalName, getName )
20 import Module ( ModuleName, mkModuleName, mkModule )
21 import RdrHsSyn ( mkClassDecl, mkTyData )
22 import qualified OccName
23 import PackageConfig ( PackageId, stringToPackageId )
24 import OccName ( startsVarId, startsVarSym, startsConId, startsConSym,
26 import SrcLoc ( Located(..), SrcSpan )
28 import TysWiredIn ( unitTyCon, tupleTyCon, tupleCon, trueDataCon, nilDataCon, consDataCon )
29 import BasicTypes( Boxity(..) )
30 import ForeignCall ( Safety(..), CCallConv(..), CCallTarget(..),
32 import Char ( isAscii, isAlphaNum, isAlpha )
33 import List ( partition )
34 import Unique ( Unique, mkUniqueGrimily )
35 import ErrUtils ( Message )
36 import GLAEXTS ( Int(..), Int# )
37 import SrcLoc ( noSrcLoc )
38 import Bag ( listToBag )
44 -------------------------------------------------------------------
45 -- The external interface
47 convertToHsDecls :: SrcSpan -> [TH.Dec] -> Either Message [LHsDecl RdrName]
48 convertToHsDecls loc ds = initCvt loc (mapM cvtTop ds)
50 convertToHsExpr :: SrcSpan -> TH.Exp -> Either Message (LHsExpr RdrName)
52 = case initCvt loc (cvtl e) of
53 Left msg -> Left (msg $$ (ptext SLIT("When converting TH expression")
55 Right res -> Right res
57 convertToHsType :: SrcSpan -> TH.Type -> Either Message (LHsType RdrName)
58 convertToHsType loc t = initCvt loc (cvtType t)
61 -------------------------------------------------------------------
62 newtype CvtM a = CvtM { unCvtM :: SrcSpan -> Either Message a }
63 -- Push down the source location;
64 -- Can fail, with a single error message
66 -- NB: If the conversion succeeds with (Right x), there should
67 -- be no exception values hiding in x
68 -- Reason: so a (head []) in TH code doesn't subsequently
69 -- make GHC crash when it tries to walk the generated tree
71 -- Use the loc everywhere, for lack of anything better
72 -- In particular, we want it on binding locations, so that variables bound in
73 -- the spliced-in declarations get a location that at least relates to the splice point
75 instance Monad CvtM where
76 return x = CvtM $ \loc -> Right x
77 (CvtM m) >>= k = CvtM $ \loc -> case m loc of
79 Right v -> unCvtM (k v) loc
81 initCvt :: SrcSpan -> CvtM a -> Either Message a
82 initCvt loc (CvtM m) = m loc
85 force a = a `seq` return a
87 failWith :: Message -> CvtM a
88 failWith m = CvtM (\loc -> Left full_msg)
90 full_msg = m $$ ptext SLIT("When splicing generated code into the program")
92 returnL :: a -> CvtM (Located a)
93 returnL x = CvtM (\loc -> Right (L loc x))
95 wrapL :: CvtM a -> CvtM (Located a)
96 wrapL (CvtM m) = CvtM (\loc -> case m loc of
98 Right v -> Right (L loc v))
100 -------------------------------------------------------------------
101 cvtTop :: TH.Dec -> CvtM (LHsDecl RdrName)
102 cvtTop d@(TH.ValD _ _ _) = do { L loc d' <- cvtBind d; return (L loc $ Hs.ValD d') }
103 cvtTop d@(TH.FunD _ _) = do { L loc d' <- cvtBind d; return (L loc $ Hs.ValD d') }
104 cvtTop (TH.SigD nm typ) = do { nm' <- vNameL nm
106 ; returnL $ Hs.SigD (TypeSig nm' ty') }
108 cvtTop (TySynD tc tvs rhs)
109 = do { tc' <- tconNameL tc
111 ; rhs' <- cvtType rhs
112 ; returnL $ TyClD (TySynonym tc' tvs' rhs') }
114 cvtTop (DataD ctxt tc tvs constrs derivs)
115 = do { stuff <- cvt_tycl_hdr ctxt tc tvs
116 ; cons' <- mapM cvtConstr constrs
117 ; derivs' <- cvtDerivs derivs
118 ; returnL $ TyClD (mkTyData DataType stuff Nothing cons' derivs') }
121 cvtTop (NewtypeD ctxt tc tvs constr derivs)
122 = do { stuff <- cvt_tycl_hdr ctxt tc tvs
123 ; con' <- cvtConstr constr
124 ; derivs' <- cvtDerivs derivs
125 ; returnL $ TyClD (mkTyData NewType stuff Nothing [con'] derivs') }
127 cvtTop (ClassD ctxt cl tvs fds decs)
128 = do { stuff <- cvt_tycl_hdr ctxt cl tvs
129 ; fds' <- mapM cvt_fundep fds
130 ; (binds', sigs') <- cvtBindsAndSigs decs
131 ; returnL $ TyClD $ mkClassDecl stuff fds' sigs' binds' }
133 cvtTop (InstanceD tys ty decs)
134 = do { (binds', sigs') <- cvtBindsAndSigs decs
135 ; ctxt' <- cvtContext tys
136 ; L loc pred' <- cvtPred ty
137 ; inst_ty' <- returnL $ mkImplicitHsForAllTy ctxt' (L loc (HsPredTy pred'))
138 ; returnL $ InstD (InstDecl inst_ty' binds' sigs') }
140 cvtTop (ForeignD ford) = do { ford' <- cvtForD ford; returnL $ ForD ford' }
142 cvt_tycl_hdr cxt tc tvs
143 = do { cxt' <- cvtContext cxt
144 ; tc' <- tconNameL tc
146 ; return (cxt', tc', tvs') }
148 ---------------------------------------------------
150 -- Can't handle GADTs yet
151 ---------------------------------------------------
153 cvtConstr (NormalC c strtys)
154 = do { c' <- cNameL c
156 ; tys' <- mapM cvt_arg strtys
157 ; returnL $ ConDecl c' Explicit noExistentials cxt' (PrefixCon tys') ResTyH98 }
159 cvtConstr (RecC c varstrtys)
160 = do { c' <- cNameL c
162 ; args' <- mapM cvt_id_arg varstrtys
163 ; returnL $ ConDecl c' Explicit noExistentials cxt' (RecCon args') ResTyH98 }
165 cvtConstr (InfixC st1 c st2)
166 = do { c' <- cNameL c
168 ; st1' <- cvt_arg st1
169 ; st2' <- cvt_arg st2
170 ; returnL $ ConDecl c' Explicit noExistentials cxt' (InfixCon st1' st2') ResTyH98 }
172 cvtConstr (ForallC tvs ctxt (ForallC tvs' ctxt' con'))
173 = cvtConstr (ForallC (tvs ++ tvs') (ctxt ++ ctxt') con')
175 cvtConstr (ForallC tvs ctxt con)
176 = do { L _ con' <- cvtConstr con
178 ; ctxt' <- cvtContext ctxt
180 ConDecl l _ [] (L _ []) x ResTyH98
181 -> returnL $ ConDecl l Explicit tvs' ctxt' x ResTyH98
182 c -> panic "ForallC: Can't happen" }
184 cvt_arg (IsStrict, ty) = do { ty' <- cvtType ty; returnL $ HsBangTy HsStrict ty' }
185 cvt_arg (NotStrict, ty) = cvtType ty
187 cvt_id_arg (i, str, ty) = do { i' <- vNameL i
188 ; ty' <- cvt_arg (str,ty)
191 cvtDerivs [] = return Nothing
192 cvtDerivs cs = do { cs' <- mapM cvt_one cs
193 ; return (Just cs') }
195 cvt_one c = do { c' <- tconName c
196 ; returnL $ HsPredTy $ HsClassP c' [] }
198 cvt_fundep :: FunDep -> CvtM (Located (Class.FunDep RdrName))
199 cvt_fundep (FunDep xs ys) = do { xs' <- mapM tName xs; ys' <- mapM tName ys; returnL (xs', ys') }
203 ------------------------------------------
204 -- Foreign declarations
205 ------------------------------------------
207 cvtForD :: Foreign -> CvtM (ForeignDecl RdrName)
208 cvtForD (ImportF callconv safety from nm ty)
209 | Just (c_header, cis) <- parse_ccall_impent (TH.nameBase nm) from
210 = do { nm' <- vNameL nm
212 ; let i = CImport (cvt_conv callconv) safety' c_header nilFS cis
213 ; return $ ForeignImport nm' ty' i False }
216 = failWith $ text (show from)<+> ptext SLIT("is not a valid ccall impent")
218 safety' = case safety of
220 Safe -> PlaySafe False
221 Threadsafe -> PlaySafe True
223 cvtForD (ExportF callconv as nm ty)
224 = do { nm' <- vNameL nm
226 ; let e = CExport (CExportStatic (mkFastString as) (cvt_conv callconv))
227 ; return $ ForeignExport nm' ty' e False }
229 cvt_conv CCall = CCallConv
230 cvt_conv StdCall = StdCallConv
232 parse_ccall_impent :: String -> String -> Maybe (FastString, CImportSpec)
233 parse_ccall_impent nm s
234 = case lex_ccall_impent s of
235 Just ["dynamic"] -> Just (nilFS, CFunction DynamicTarget)
236 Just ["wrapper"] -> Just (nilFS, CWrapper)
237 Just ("static":ts) -> parse_ccall_impent_static nm ts
238 Just ts -> parse_ccall_impent_static nm ts
241 parse_ccall_impent_static :: String
243 -> Maybe (FastString, CImportSpec)
244 parse_ccall_impent_static nm ts
245 = let ts' = case ts of
246 [ "&", cid] -> [ cid]
247 [fname, "&" ] -> [fname ]
248 [fname, "&", cid] -> [fname, cid]
251 [ cid] | is_cid cid -> Just (nilFS, mk_cid cid)
252 [fname, cid] | is_cid cid -> Just (mkFastString fname, mk_cid cid)
253 [ ] -> Just (nilFS, mk_cid nm)
254 [fname ] -> Just (mkFastString fname, mk_cid nm)
256 where is_cid :: String -> Bool
257 is_cid x = all (/= '.') x && (isAlpha (head x) || head x == '_')
258 mk_cid :: String -> CImportSpec
259 mk_cid = CFunction . StaticTarget . mkFastString
261 lex_ccall_impent :: String -> Maybe [String]
262 lex_ccall_impent "" = Just []
263 lex_ccall_impent ('&':xs) = fmap ("&":) $ lex_ccall_impent xs
264 lex_ccall_impent (' ':xs) = lex_ccall_impent xs
265 lex_ccall_impent ('\t':xs) = lex_ccall_impent xs
266 lex_ccall_impent xs = case span is_valid xs of
268 (t, xs') -> fmap (t:) $ lex_ccall_impent xs'
269 where is_valid :: Char -> Bool
270 is_valid c = isAscii c && (isAlphaNum c || c `elem` "._")
273 ---------------------------------------------------
275 ---------------------------------------------------
277 cvtDecs :: [TH.Dec] -> CvtM (HsLocalBinds RdrName)
278 cvtDecs [] = return EmptyLocalBinds
279 cvtDecs ds = do { (binds,sigs) <- cvtBindsAndSigs ds
280 ; return (HsValBinds (ValBindsIn binds sigs)) }
283 = do { binds' <- mapM cvtBind binds; sigs' <- mapM cvtSig sigs
284 ; return (listToBag binds', sigs') }
286 (sigs, binds) = partition is_sig ds
288 is_sig (TH.SigD _ _) = True
291 cvtSig (TH.SigD nm ty)
292 = do { nm' <- vNameL nm; ty' <- cvtType ty; returnL (Hs.TypeSig nm' ty') }
294 cvtBind :: TH.Dec -> CvtM (LHsBind RdrName)
295 -- Used only for declarations in a 'let/where' clause,
296 -- not for top level decls
297 cvtBind (TH.ValD (TH.VarP s) body ds)
298 = do { s' <- vNameL s
299 ; cl' <- cvtClause (Clause [] body ds)
300 ; returnL $ mkFunBind s' [cl'] }
302 cvtBind (TH.FunD nm cls)
303 = do { nm' <- vNameL nm
304 ; cls' <- mapM cvtClause cls
305 ; returnL $ mkFunBind nm' cls' }
307 cvtBind (TH.ValD p body ds)
308 = do { p' <- cvtPat p
309 ; g' <- cvtGuard body
311 ; returnL $ PatBind { pat_lhs = p', pat_rhs = GRHSs g' ds',
312 pat_rhs_ty = void, bind_fvs = placeHolderNames } }
315 = failWith (sep [ptext SLIT("Illegal kind of declaration in where clause"),
316 nest 2 (text (TH.pprint d))])
318 cvtClause :: TH.Clause -> CvtM (Hs.LMatch RdrName)
319 cvtClause (Clause ps body wheres)
320 = do { ps' <- cvtPats ps
321 ; g' <- cvtGuard body
322 ; ds' <- cvtDecs wheres
323 ; returnL $ Hs.Match ps' Nothing (GRHSs g' ds') }
326 -------------------------------------------------------------------
328 -------------------------------------------------------------------
330 cvtl :: TH.Exp -> CvtM (LHsExpr RdrName)
331 cvtl e = wrapL (cvt e)
333 cvt (VarE s) = do { s' <- vName s; return $ HsVar s' }
334 cvt (ConE s) = do { s' <- cName s; return $ HsVar s' }
336 | overloadedLit l = do { l' <- cvtOverLit l; return $ HsOverLit l' }
337 | otherwise = do { l' <- cvtLit l; return $ HsLit l' }
339 cvt (AppE x y) = do { x' <- cvtl x; y' <- cvtl y; return $ HsApp x' y' }
340 cvt (LamE ps e) = do { ps' <- cvtPats ps; e' <- cvtl e
341 ; return $ HsLam (mkMatchGroup [mkSimpleMatch ps' e']) }
342 cvt (TupE [e]) = cvt e
343 cvt (TupE es) = do { es' <- mapM cvtl es; return $ ExplicitTuple es' Boxed }
344 cvt (CondE x y z) = do { x' <- cvtl x; y' <- cvtl y; z' <- cvtl z
345 ; return $ HsIf x' y' z' }
346 cvt (LetE ds e) = do { ds' <- cvtDecs ds; e' <- cvtl e; return $ HsLet ds' e' }
347 cvt (CaseE e ms) = do { e' <- cvtl e; ms' <- mapM cvtMatch ms
348 ; return $ HsCase e' (mkMatchGroup ms') }
349 cvt (DoE ss) = cvtHsDo DoExpr ss
350 cvt (CompE ss) = cvtHsDo ListComp ss
351 cvt (ArithSeqE dd) = do { dd' <- cvtDD dd; return $ ArithSeq noPostTcExpr dd' }
352 cvt (ListE xs) = do { xs' <- mapM cvtl xs; return $ ExplicitList void xs' }
353 cvt (InfixE (Just x) s (Just y)) = do { x' <- cvtl x; s' <- cvtl s; y' <- cvtl y
354 ; e' <- returnL $ OpApp x' s' undefined y'
355 ; return $ HsPar e' }
356 cvt (InfixE Nothing s (Just y)) = do { s' <- cvtl s; y' <- cvtl y
357 ; return $ SectionR s' y' }
358 cvt (InfixE (Just x) s Nothing ) = do { x' <- cvtl x; s' <- cvtl s
359 ; return $ SectionL x' s' }
360 cvt (InfixE Nothing s Nothing ) = cvt s -- Can I indicate this is an infix thing?
362 cvt (SigE e t) = do { e' <- cvtl e; t' <- cvtType t
363 ; return $ ExprWithTySig e' t' }
364 cvt (RecConE c flds) = do { c' <- cNameL c
365 ; flds' <- mapM cvtFld flds
366 ; return $ RecordCon c' noPostTcExpr flds' }
367 cvt (RecUpdE e flds) = do { e' <- cvtl e
368 ; flds' <- mapM cvtFld flds
369 ; return $ RecordUpd e' flds' placeHolderType placeHolderType }
371 cvtFld (v,e) = do { v' <- vNameL v; e' <- cvtl e; return (v',e') }
373 cvtDD :: Range -> CvtM (ArithSeqInfo RdrName)
374 cvtDD (FromR x) = do { x' <- cvtl x; return $ From x' }
375 cvtDD (FromThenR x y) = do { x' <- cvtl x; y' <- cvtl y; return $ FromThen x' y' }
376 cvtDD (FromToR x y) = do { x' <- cvtl x; y' <- cvtl y; return $ FromTo x' y' }
377 cvtDD (FromThenToR x y z) = do { x' <- cvtl x; y' <- cvtl y; z' <- cvtl z; return $ FromThenTo x' y' z' }
379 -------------------------------------
380 -- Do notation and statements
381 -------------------------------------
383 cvtHsDo do_or_lc stmts
384 = do { stmts' <- cvtStmts stmts
385 ; let body = case last stmts' of
386 L _ (ExprStmt body _ _) -> body
387 ; return $ HsDo do_or_lc (init stmts') body void }
389 cvtStmts = mapM cvtStmt
391 cvtStmt :: TH.Stmt -> CvtM (Hs.LStmt RdrName)
392 cvtStmt (NoBindS e) = do { e' <- cvtl e; returnL $ mkExprStmt e' }
393 cvtStmt (TH.BindS p e) = do { p' <- cvtPat p; e' <- cvtl e; returnL $ mkBindStmt p' e' }
394 cvtStmt (TH.LetS ds) = do { ds' <- cvtDecs ds; returnL $ LetStmt ds' }
395 cvtStmt (TH.ParS dss) = do { dss' <- mapM cvt_one dss; returnL $ ParStmt dss' }
397 cvt_one ds = do { ds' <- cvtStmts ds; return (ds', undefined) }
399 cvtMatch :: TH.Match -> CvtM (Hs.LMatch RdrName)
400 cvtMatch (TH.Match p body decs)
401 = do { p' <- cvtPat p
402 ; g' <- cvtGuard body
403 ; decs' <- cvtDecs decs
404 ; returnL $ Hs.Match [p'] Nothing (GRHSs g' decs') }
406 cvtGuard :: TH.Body -> CvtM [LGRHS RdrName]
407 cvtGuard (GuardedB pairs) = mapM cvtpair pairs
408 cvtGuard (NormalB e) = do { e' <- cvtl e; g' <- returnL $ GRHS [] e'; return [g'] }
410 cvtpair :: (TH.Guard, TH.Exp) -> CvtM (LGRHS RdrName)
411 cvtpair (NormalG ge,rhs) = do { ge' <- cvtl ge; rhs' <- cvtl rhs
412 ; g' <- returnL $ mkBindStmt truePat ge'
413 ; returnL $ GRHS [g'] rhs' }
414 cvtpair (PatG gs,rhs) = do { gs' <- cvtStmts gs; rhs' <- cvtl rhs
415 ; returnL $ GRHS gs' rhs' }
417 cvtOverLit :: Lit -> CvtM (HsOverLit RdrName)
418 cvtOverLit (IntegerL i) = do { force i; return $ mkHsIntegral i }
419 cvtOverLit (RationalL r) = do { force r; return $ mkHsFractional r }
420 -- An Integer is like an an (overloaded) '3' in a Haskell source program
421 -- Similarly 3.5 for fractionals
423 cvtLit :: Lit -> CvtM HsLit
424 cvtLit (IntPrimL i) = do { force i; return $ HsIntPrim i }
425 cvtLit (FloatPrimL f) = do { force f; return $ HsFloatPrim f }
426 cvtLit (DoublePrimL f) = do { force f; return $ HsDoublePrim f }
427 cvtLit (CharL c) = do { force c; return $ HsChar c }
428 cvtLit (StringL s) = do { let { s' = mkFastString s }; force s'; return $ HsString s' }
430 cvtPats :: [TH.Pat] -> CvtM [Hs.LPat RdrName]
431 cvtPats pats = mapM cvtPat pats
433 cvtPat :: TH.Pat -> CvtM (Hs.LPat RdrName)
434 cvtPat pat = wrapL (cvtp pat)
436 cvtp :: TH.Pat -> CvtM (Hs.Pat RdrName)
438 | overloadedLit l = do { l' <- cvtOverLit l
439 ; return (mkNPat l' Nothing) }
440 -- Not right for negative patterns;
441 -- need to think about that!
442 | otherwise = do { l' <- cvtLit l; return $ Hs.LitPat l' }
443 cvtp (TH.VarP s) = do { s' <- vName s; return $ Hs.VarPat s' }
444 cvtp (TupP [p]) = cvtp p
445 cvtp (TupP ps) = do { ps' <- cvtPats ps; return $ TuplePat ps' Boxed void }
446 cvtp (ConP s ps) = do { s' <- cNameL s; ps' <- cvtPats ps; return $ ConPatIn s' (PrefixCon ps') }
447 cvtp (InfixP p1 s p2) = do { s' <- cNameL s; p1' <- cvtPat p1; p2' <- cvtPat p2
448 ; return $ ConPatIn s' (InfixCon p1' p2') }
449 cvtp (TildeP p) = do { p' <- cvtPat p; return $ LazyPat p' }
450 cvtp (TH.AsP s p) = do { s' <- vNameL s; p' <- cvtPat p; return $ AsPat s' p' }
451 cvtp TH.WildP = return $ WildPat void
452 cvtp (RecP c fs) = do { c' <- cNameL c; fs' <- mapM cvtPatFld fs
453 ; return $ ConPatIn c' $ Hs.RecCon fs' }
454 cvtp (ListP ps) = do { ps' <- cvtPats ps; return $ ListPat ps' void }
455 cvtp (SigP p t) = do { p' <- cvtPat p; t' <- cvtType t; return $ SigPatIn p' t' }
457 cvtPatFld (s,p) = do { s' <- vNameL s; p' <- cvtPat p; return (s',p') }
459 -----------------------------------------------------------
460 -- Types and type variables
462 cvtTvs :: [TH.Name] -> CvtM [LHsTyVarBndr RdrName]
463 cvtTvs tvs = mapM cvt_tv tvs
465 cvt_tv tv = do { tv' <- tName tv; returnL $ UserTyVar tv' }
467 cvtContext :: Cxt -> CvtM (LHsContext RdrName)
468 cvtContext tys = do { preds' <- mapM cvtPred tys; returnL preds' }
470 cvtPred :: TH.Type -> CvtM (LHsPred RdrName)
472 = do { (head, tys') <- split_ty_app ty
474 ConT tc -> do { tc' <- tconName tc; returnL $ HsClassP tc' tys' }
475 VarT tv -> do { tv' <- tName tv; returnL $ HsClassP tv' tys' }
476 other -> failWith (ptext SLIT("Malformed predicate") <+> text (TH.pprint ty)) }
478 cvtType :: TH.Type -> CvtM (LHsType RdrName)
479 cvtType ty = do { (head, tys') <- split_ty_app ty
481 TupleT n | length tys' == n -> returnL (HsTupleTy Boxed tys')
482 | n == 0 -> mk_apps (HsTyVar (getRdrName unitTyCon)) tys'
483 | otherwise -> mk_apps (HsTyVar (getRdrName (tupleTyCon Boxed n))) tys'
484 ArrowT | [x',y'] <- tys' -> returnL (HsFunTy x' y')
485 ListT | [x'] <- tys' -> returnL (HsListTy x')
486 VarT nm -> do { nm' <- tName nm; mk_apps (HsTyVar nm') tys' }
487 ConT nm -> do { nm' <- tconName nm; mk_apps (HsTyVar nm') tys' }
489 ForallT tvs cxt ty | null tys' -> do { tvs' <- cvtTvs tvs
490 ; cxt' <- cvtContext cxt
492 ; returnL $ mkExplicitHsForAllTy tvs' cxt' ty' }
493 otherwise -> failWith (ptext SLIT("Malformed type") <+> text (show ty))
496 mk_apps head [] = returnL head
497 mk_apps head (ty:tys) = do { head' <- returnL head; mk_apps (HsAppTy head' ty) tys }
499 split_ty_app :: TH.Type -> CvtM (TH.Type, [LHsType RdrName])
500 split_ty_app ty = go ty []
502 go (AppT f a) as' = do { a' <- cvtType a; go f (a':as') }
503 go f as = return (f,as)
505 -----------------------------------------------------------
508 -----------------------------------------------------------
509 -- some useful things
511 truePat = nlConPat (getRdrName trueDataCon) []
513 overloadedLit :: Lit -> Bool
514 -- True for literals that Haskell treats as overloaded
515 overloadedLit (IntegerL l) = True
516 overloadedLit (RationalL l) = True
517 overloadedLit l = False
520 void = placeHolderType
522 --------------------------------------------------------------------
523 -- Turning Name back into RdrName
524 --------------------------------------------------------------------
527 vNameL, cNameL, tconNameL :: TH.Name -> CvtM (Located RdrName)
528 vName, cName, tName, tconName :: TH.Name -> CvtM RdrName
530 vNameL n = wrapL (vName n)
531 vName n = cvtName OccName.varName n
533 -- Constructor function names; this is Haskell source, hence srcDataName
534 cNameL n = wrapL (cName n)
535 cName n = cvtName OccName.dataName n
537 -- Type variable names
538 tName n = cvtName OccName.tvName n
540 -- Type Constructor names
541 tconNameL n = wrapL (tconName n)
542 tconName n = cvtName OccName.tcClsName n
544 cvtName :: OccName.NameSpace -> TH.Name -> CvtM RdrName
545 cvtName ctxt_ns (TH.Name occ flavour)
546 | not (okOcc ctxt_ns occ_str) = failWith (badOcc ctxt_ns occ_str)
547 | otherwise = force (thRdrName ctxt_ns occ_str flavour)
549 occ_str = TH.occString occ
551 okOcc :: OccName.NameSpace -> String -> Bool
554 | OccName.isVarName ns = startsVarId c || startsVarSym c
555 | otherwise = startsConId c || startsConSym c || str == "[]"
557 badOcc :: OccName.NameSpace -> String -> SDoc
559 = ptext SLIT("Illegal") <+> pprNameSpace ctxt_ns
560 <+> ptext SLIT("name:") <+> quotes (text occ)
562 thRdrName :: OccName.NameSpace -> String -> TH.NameFlavour -> RdrName
563 -- This turns a Name into a RdrName
564 -- The passed-in name space tells what the context is expecting;
565 -- use it unless the TH name knows what name-space it comes
566 -- from, in which case use the latter
568 -- ToDo: we may generate silly RdrNames, by passing a name space
569 -- that doesn't match the string, like VarName ":+",
570 -- which will give confusing error messages later
572 -- The strict applications ensure that any buried exceptions get forced
573 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)
574 thRdrName ctxt_ns occ (TH.NameL uniq) = nameRdrName $! (((Name.mkInternalName $! (mk_uniq uniq)) $! (mk_occ ctxt_ns occ)) noSrcLoc)
575 thRdrName ctxt_ns occ (TH.NameQ mod) = (mkRdrQual $! (mk_mod mod)) $! (mk_occ ctxt_ns occ)
576 thRdrName ctxt_ns occ (TH.NameU uniq) = mkRdrUnqual $! (mk_uniq_occ ctxt_ns occ uniq)
577 thRdrName ctxt_ns occ TH.NameS
578 | Just name <- isBuiltInOcc ctxt_ns occ = nameRdrName $! name
579 | otherwise = mkRdrUnqual $! (mk_occ ctxt_ns occ)
581 isBuiltInOcc :: OccName.NameSpace -> String -> Maybe Name.Name
582 -- Built in syntax isn't "in scope" so an Unqual RdrName won't do
583 -- We must generate an Exact name, just as the parser does
584 isBuiltInOcc ctxt_ns occ
586 ":" -> Just (Name.getName consDataCon)
587 "[]" -> Just (Name.getName nilDataCon)
588 "()" -> Just (tup_name 0)
589 '(' : ',' : rest -> go_tuple 2 rest
592 go_tuple n ")" = Just (tup_name n)
593 go_tuple n (',' : rest) = go_tuple (n+1) rest
594 go_tuple n other = Nothing
597 | OccName.isTcClsName ctxt_ns = Name.getName (tupleTyCon Boxed n)
598 | otherwise = Name.getName (tupleCon Boxed n)
600 mk_uniq_occ :: OccName.NameSpace -> String -> Int# -> OccName.OccName
601 mk_uniq_occ ns occ uniq
602 = OccName.mkOccName ns (occ ++ '[' : shows (mk_uniq uniq) "]")
603 -- The idea here is to make a name that
604 -- a) the user could not possibly write, and
605 -- b) cannot clash with another NameU
606 -- Previously I generated an Exact RdrName with mkInternalName.
607 -- This works fine for local binders, but does not work at all for
608 -- top-level binders, which must have External Names, since they are
609 -- rapidly baked into data constructors and the like. Baling out
610 -- and generating an unqualified RdrName here is the simple solution
612 -- The packing and unpacking is rather turgid :-(
613 mk_occ :: OccName.NameSpace -> String -> OccName.OccName
614 mk_occ ns occ = OccName.mkOccNameFS ns (mkFastString occ)
616 mk_ghc_ns :: TH.NameSpace -> OccName.NameSpace
617 mk_ghc_ns TH.DataName = OccName.dataName
618 mk_ghc_ns TH.TcClsName = OccName.tcClsName
619 mk_ghc_ns TH.VarName = OccName.varName
621 mk_mod :: TH.ModName -> ModuleName
622 mk_mod mod = mkModuleName (TH.modString mod)
624 mk_pkg :: TH.ModName -> PackageId
625 mk_pkg pkg = stringToPackageId (TH.pkgString pkg)
627 mk_uniq :: Int# -> Unique
628 mk_uniq u = mkUniqueGrimily (I# u)