7 #include "HsVersions.h"
9 import HsSyn ( MonoBinds(..) )
10 import HscTypes ( HscEnv(..), PersistentCompilerState(..),
11 emptyFixityEnv, emptyGlobalRdrEnv, TyThing,
12 ExternalPackageState(..), HomePackageTable,
13 ModDetails(..), HomeModInfo(..), Deprecations(..),
14 GlobalRdrEnv, LocalRdrEnv, NameCache, FixityEnv,
15 GhciMode, lookupType, unQualInScope )
17 import Module ( Module, foldModuleEnv )
18 import Name ( Name, isInternalName )
20 import NameEnv ( extendNameEnvList )
21 import InstEnv ( InstEnv, extendInstEnv )
22 import TysWiredIn ( integerTy, doubleTy )
24 import VarSet ( emptyVarSet )
25 import VarEnv ( TidyEnv, emptyTidyEnv )
26 import RdrName ( emptyRdrEnv )
27 import ErrUtils ( Message, Messages, emptyMessages, errorsFound,
28 addShortErrLocLine, addShortWarnLocLine, printErrorsAndWarnings )
29 import SrcLoc ( SrcLoc, noSrcLoc )
30 import NameEnv ( emptyNameEnv )
31 import Bag ( emptyBag )
33 import UniqSupply ( UniqSupply, mkSplitUniqSupply, uniqFromSupply, splitUniqSupply )
34 import Unique ( Unique )
35 import CmdLineOpts ( DynFlags, DynFlag(..), dopt, opt_PprStyle_Debug )
36 import BasicTypes ( FixitySig )
37 import Bag ( snocBag, unionBags )
39 import Maybe ( isJust )
41 import DATA_IOREF ( newIORef, readIORef )
44 %************************************************************************
46 Standard combinators, but specialised for this monad
49 6%************************************************************************
52 mappM :: (a -> TcRn m b) -> [a] -> TcRn m [b]
53 mappM_ :: (a -> TcRn m b) -> [a] -> TcRn m ()
54 -- Funny names to avoid clash with Prelude
55 sequenceM :: [TcRn m a] -> TcRn m [a]
56 foldlM :: (a -> b -> TcRn m a) -> a -> [b] -> TcRn m a
57 mapAndUnzipM :: (a -> TcRn m (b,c)) -> [a] -> TcRn m ([b],[c])
58 mapAndUnzip3M :: (a -> TcRn m (b,c,d)) -> [a] -> TcRn m ([b],[c],[d])
59 checkM :: Bool -> TcRn m () -> TcRn m () -- Perform arg if bool is False
60 ifM :: Bool -> TcRn m () -> TcRn m () -- Perform arg if bool is True
62 mappM f [] = return []
63 mappM f (x:xs) = do { r <- f x; rs <- mappM f xs; return (r:rs) }
65 mappM_ f [] = return ()
66 mappM_ f (x:xs) = f x >> mappM_ f xs
68 sequenceM [] = return []
69 sequenceM (x:xs) = do { r <- x; rs <- sequenceM xs; return (r:rs) }
71 foldlM k z [] = return z
72 foldlM k z (x:xs) = do { r <- k z x; foldlM k r xs }
74 mapAndUnzipM f [] = return ([],[])
75 mapAndUnzipM f (x:xs) = do { (r,s) <- f x;
76 (rs,ss) <- mapAndUnzipM f xs;
79 mapAndUnzip3M f [] = return ([],[], [])
80 mapAndUnzip3M f (x:xs) = do { (r,s,t) <- f x;
81 (rs,ss,ts) <- mapAndUnzip3M f xs;
82 return (r:rs, s:ss, t:ts) }
84 checkM True err = return ()
85 checkM False err = err
87 ifM True do_it = do_it
88 ifM False do_it = return ()
92 %************************************************************************
96 %************************************************************************
99 initTc :: HscEnv -> PersistentCompilerState
102 -> IO (PersistentCompilerState, Maybe r)
103 -- Nothing => error thrown by the thing inside
104 -- (error messages should have been printed already)
106 initTc (HscEnv { hsc_mode = ghci_mode,
108 hsc_dflags = dflags })
110 = do { us <- mkSplitUniqSupply 'a' ;
111 us_var <- newIORef us ;
112 errs_var <- newIORef (emptyBag, emptyBag) ;
113 tvs_var <- newIORef emptyVarSet ;
114 usg_var <- newIORef emptyUsages ;
115 nc_var <- newIORef (pcs_nc pcs) ;
116 eps_var <- newIORef eps ;
119 env = Env { env_top = top_env,
122 env_loc = noSrcLoc } ;
125 top_mode = ghci_mode,
131 top_errs = errs_var } ;
135 tcg_usages = usg_var,
136 tcg_rdr_env = emptyGlobalRdrEnv,
137 tcg_fix_env = emptyFixityEnv,
138 tcg_default = defaultDefaultTys,
139 tcg_type_env = emptyNameEnv,
140 tcg_ist = mkImpTypeEnv eps hpt,
141 tcg_inst_env = mkImpInstEnv dflags eps hpt,
143 tcg_imports = emptyImportAvails,
144 tcg_binds = EmptyMonoBinds,
145 tcg_deprecs = NoDeprecs,
152 tcl_level = topStage,
153 tcl_env = emptyNameEnv,
154 tcl_tyvars = tvs_var,
155 tcl_lie = panic "initTc:LIE" } ;
156 -- LIE only valid inside a getLIE
159 -- OK, here's the business end!
160 maybe_res <- catch (do { res <- runTcRn env do_this ;
162 (\_ -> return Nothing) ;
164 -- Print any error messages
165 msgs <- readIORef errs_var ;
166 printErrorsAndWarnings msgs ;
168 -- Get final PCS and return
169 eps' <- readIORef eps_var ;
170 nc' <- readIORef nc_var ;
171 let { pcs' = PCS { pcs_EPS = eps', pcs_nc = nc' } ;
172 final_res | errorsFound msgs = Nothing
173 | otherwise = maybe_res } ;
175 return (pcs', final_res)
180 defaultDefaultTys :: [Type]
181 defaultDefaultTys = [integerTy, doubleTy]
183 mkImpInstEnv :: DynFlags -> ExternalPackageState -> HomePackageTable -> InstEnv
184 mkImpInstEnv dflags eps hpt
185 = foldModuleEnv (add . md_insts . hm_details)
189 -- We shouldn't get instance conflict errors from
190 -- the package and home type envs
191 add dfuns inst_env = WARN( not (null errs), vcat errs ) inst_env'
193 (inst_env', errs) = extendInstEnv dflags inst_env dfuns
195 -- mkImpTypeEnv makes the imported symbol table
196 mkImpTypeEnv :: ExternalPackageState -> HomePackageTable
197 -> Name -> Maybe TyThing
198 mkImpTypeEnv pcs hpt = lookup
201 lookup name | isInternalName name = Nothing
202 | otherwise = lookupType hpt pte name
206 %************************************************************************
210 %************************************************************************
213 getTopEnv :: TcRn m TopEnv
214 getTopEnv = do { env <- getEnv; return (env_top env) }
216 getGblEnv :: TcRn m TcGblEnv
217 getGblEnv = do { env <- getEnv; return (env_gbl env) }
219 updGblEnv :: (TcGblEnv -> TcGblEnv) -> TcRn m a -> TcRn m a
220 updGblEnv upd = updEnv (\ env@(Env { env_gbl = gbl }) ->
221 env { env_gbl = upd gbl })
223 setGblEnv :: TcGblEnv -> TcRn m a -> TcRn m a
224 setGblEnv gbl_env = updEnv (\ env -> env { env_gbl = gbl_env })
226 getLclEnv :: TcRn m m
227 getLclEnv = do { env <- getEnv; return (env_lcl env) }
229 updLclEnv :: (m -> m) -> TcRn m a -> TcRn m a
230 updLclEnv upd = updEnv (\ env@(Env { env_lcl = lcl }) ->
231 env { env_lcl = upd lcl })
233 setLclEnv :: m -> TcRn m a -> TcRn n a
234 setLclEnv lcl_env = updEnv (\ env -> env { env_lcl = lcl_env })
240 getDOpts :: TcRn m DynFlags
241 getDOpts = do { env <- getTopEnv; return (top_dflags env) }
243 doptM :: DynFlag -> TcRn m Bool
244 doptM flag = do { dflags <- getDOpts; return (dopt flag dflags) }
246 ifOptM :: DynFlag -> TcRn m () -> TcRn m () -- Do it flag is true
247 ifOptM flag thing_inside = do { b <- doptM flag;
248 if b then thing_inside else return () }
250 getGhciMode :: TcRn m GhciMode
251 getGhciMode = do { env <- getTopEnv; return (top_mode env) }
255 getSrcLocM :: TcRn m SrcLoc
256 -- Avoid clash with Name.getSrcLoc
257 getSrcLocM = do { env <- getEnv; return (env_loc env) }
259 addSrcLoc :: SrcLoc -> TcRn m a -> TcRn m a
260 addSrcLoc loc = updEnv (\env -> env { env_loc = loc })
264 getEps :: TcRn m ExternalPackageState
265 getEps = do { env <- getTopEnv; readMutVar (top_eps env) }
267 setEps :: ExternalPackageState -> TcRn m ()
268 setEps eps = do { env <- getTopEnv; writeMutVar (top_eps env) eps }
270 getHpt :: TcRn m HomePackageTable
271 getHpt = do { env <- getTopEnv; return (top_hpt env) }
273 getModule :: TcRn m Module
274 getModule = do { env <- getGblEnv; return (tcg_mod env) }
276 getGlobalRdrEnv :: TcRn m GlobalRdrEnv
277 getGlobalRdrEnv = do { env <- getGblEnv; return (tcg_rdr_env env) }
279 getFixityEnv :: TcRn m FixityEnv
280 getFixityEnv = do { env <- getGblEnv; return (tcg_fix_env env) }
282 extendFixityEnv :: [(Name,FixitySig Name)] -> RnM a -> RnM a
283 extendFixityEnv new_bit
284 = updGblEnv (\env@(TcGblEnv { tcg_fix_env = old_fix_env }) ->
285 env {tcg_fix_env = extendNameEnvList old_fix_env new_bit})
287 getDefaultTys :: TcRn m [Type]
288 getDefaultTys = do { env <- getGblEnv; return (tcg_default env) }
292 getUsageVar :: TcRn m (TcRef Usages)
293 getUsageVar = do { env <- getGblEnv; return (tcg_usages env) }
295 getUsages :: TcRn m Usages
296 getUsages = do { usg_var <- getUsageVar; readMutVar usg_var }
298 updUsages :: (Usages -> Usages) -> TcRn m ()
299 updUsages upd = do { usg_var <- getUsageVar ;
300 usg <- readMutVar usg_var ;
301 writeMutVar usg_var (upd usg) }
305 %************************************************************************
309 %************************************************************************
312 getErrsVar :: TcRn m (TcRef Messages)
313 getErrsVar = do { env <- getTopEnv; return (top_errs env) }
315 setErrsVar :: TcRef Messages -> TcRn m a -> TcRn m a
316 setErrsVar v = updEnv (\ env@(Env { env_top = top_env }) ->
317 env { env_top = top_env { top_errs = v }})
319 addErr :: Message -> TcRn m ()
320 addErr msg = do { loc <- getSrcLocM ; add_err loc msg }
322 add_err :: SrcLoc -> Message -> TcRn m ()
324 = do { errs_var <- getErrsVar ;
325 rdr_env <- getGlobalRdrEnv ;
326 let { err = addShortErrLocLine loc (unQualInScope rdr_env) msg } ;
327 (warns, errs) <- readMutVar errs_var ;
328 writeMutVar errs_var (warns, errs `snocBag` err) }
330 addErrs :: [Message] -> TcRn m ()
331 addErrs msgs = mappM_ addErr msgs
333 addWarn :: Message -> TcRn m ()
335 = do { errs_var <- getErrsVar ;
337 rdr_env <- getGlobalRdrEnv ;
338 let { warn = addShortWarnLocLine loc (unQualInScope rdr_env) msg } ;
339 (warns, errs) <- readMutVar errs_var ;
340 writeMutVar errs_var (warns `snocBag` warn, errs) }
342 checkErr :: Bool -> Message -> TcRn m ()
343 -- Add the error if the bool is False
344 checkErr ok msg = checkM ok (addErr msg)
346 warnIf :: Bool -> Message -> TcRn m ()
347 warnIf True msg = addWarn msg
348 warnIf False msg = return ()
350 addMessages :: Messages -> TcRn m ()
351 addMessages (m_warns, m_errs)
352 = do { errs_var <- getErrsVar ;
353 (warns, errs) <- readMutVar errs_var ;
354 writeMutVar errs_var (warns `unionBags` m_warns,
355 errs `unionBags` m_errs) }
357 checkGHCI :: Message -> TcRn m () -- Check that GHCI is on
358 -- otherwise add the error message
360 checkGHCI m = returnM ()
362 checkGHCI m = addErr m
368 tryM :: TcRn m a -> TcRn m (Messages, Maybe a)
369 -- (try m) executes m, and returns
370 -- Just r, if m succeeds (returning r) and caused no errors
371 -- Nothing, if m fails, or caused errors
372 -- It also returns all the errors accumulated by m
373 -- (even in the Just case, there might be warnings)
375 -- It always succeeds (never raises an exception)
377 = do { errs_var <- newMutVar emptyMessages ;
379 mb_r <- recoverM (return Nothing)
380 (do { r <- setErrsVar errs_var m ;
383 new_errs <- readMutVar errs_var ;
388 Just r | errorsFound new_errs -> Nothing
389 | otherwise -> Just r)
392 tryTc :: TcM a -> TcM (Messages, Maybe a)
393 -- Just like tryM, except that it ensures that the LIE
394 -- for the thing is propagated only if there are no errors
395 -- Hence it's restricted to the type-check monad
397 = do { ((errs, mb_r), lie) <- getLIE (tryM thing_inside) ;
398 ifM (isJust mb_r) (extendLIEs lie) ;
399 return (errs, mb_r) }
401 tryTc_ :: TcM r -> TcM r -> TcM r
402 -- (tryM_ r m) tries m; if it succeeds it returns it,
403 -- otherwise it returns r. Any error messages added by m are discarded,
404 -- whether or not m succeeds.
406 = do { (_msgs, mb_res) <- tryTc main ;
408 Just res -> return res
411 checkNoErrs :: TcM r -> TcM r
412 -- (checkNoErrs m) succeeds iff m succeeds and generates no errors
413 -- If m fails then (checkNoErrsTc m) fails.
414 -- If m succeeds, it checks whether m generated any errors messages
415 -- (it might have recovered internally)
416 -- If so, it fails too.
417 -- Regardless, any errors generated by m are propagated to the enclosing context.
419 = do { (msgs, mb_res) <- tryTc main ;
426 ifErrsM :: TcRn m r -> TcRn m r -> TcRn m r
427 -- ifErrsM bale_out main
428 -- does 'bale_out' if there are errors in errors collection
429 -- otherwise does 'main'
430 ifErrsM bale_out normal
431 = do { errs_var <- getErrsVar ;
432 msgs <- readMutVar errs_var ;
433 if errorsFound msgs then
438 failIfErrsM :: TcRn m ()
439 -- Useful to avoid error cascades
440 failIfErrsM = ifErrsM failM (return ())
444 forkM :: SDoc -> TcM a -> TcM (Maybe a)
445 -- Run thing_inside in an interleaved thread. It gets a separate
448 -- but everything else is shared, so this is DANGEROUS.
450 -- It returns Nothing if the computation fails
452 -- It's used for lazily type-checking interface
453 -- signatures, which is pretty benign
455 forkM doc thing_inside
456 = do { us <- newUniqueSupply ;
458 do { us_var <- newMutVar us ;
459 (msgs, mb_res) <- tryTc (setUsVar us_var thing_inside) ;
461 Just r -> return (Just r)
463 -- Bleat about errors in the forked thread
464 ioToTcRn (do { printErrs (hdr_doc defaultErrStyle) ;
465 printErrorsAndWarnings msgs }) ;
469 hdr_doc = text "forkM failed:" <+> doc
473 %************************************************************************
477 %************************************************************************
480 getUsVar :: TcRn m (TcRef UniqSupply)
481 getUsVar = do { env <- getTopEnv; return (top_us env) }
483 setUsVar :: TcRef UniqSupply -> TcRn m a -> TcRn m a
484 setUsVar v = updEnv (\ env@(Env { env_top = top_env }) ->
485 env { env_top = top_env { top_us = v }})
487 newUnique :: TcRn m Unique
488 newUnique = do { us <- newUniqueSupply ;
489 return (uniqFromSupply us) }
491 newUniqueSupply :: TcRn m UniqSupply
493 = do { u_var <- getUsVar ;
494 us <- readMutVar u_var ;
495 let { (us1, us2) = splitUniqSupply us } ;
496 writeMutVar u_var us1 ;
502 getNameCache :: TcRn m NameCache
503 getNameCache = do { TopEnv { top_nc = nc_var } <- getTopEnv;
506 setNameCache :: NameCache -> TcRn m ()
507 setNameCache nc = do { TopEnv { top_nc = nc_var } <- getTopEnv;
508 writeMutVar nc_var nc }
512 %************************************************************************
516 %************************************************************************
519 traceTc, traceRn :: SDoc -> TcRn a ()
520 traceRn = dumpOptTcRn Opt_D_dump_rn_trace
521 traceTc = dumpOptTcRn Opt_D_dump_tc_trace
522 traceHiDiffs = dumpOptTcRn Opt_D_dump_hi_diffs
524 dumpOptTcRn :: DynFlag -> SDoc -> TcRn a ()
525 dumpOptTcRn flag doc = ifOptM flag (dumpTcRn doc)
527 dumpTcRn :: SDoc -> TcRn a ()
528 dumpTcRn doc = do { rdr_env <- getGlobalRdrEnv ;
529 ioToTcRn (printForUser stderr (unQualInScope rdr_env) doc) }
533 %************************************************************************
535 Context management and error message generation
538 %************************************************************************
541 setErrCtxtM, addErrCtxtM :: (TidyEnv -> TcM (TidyEnv, Message)) -> TcM a -> TcM a
542 setErrCtxtM msg = updCtxt (\ msgs -> [msg])
543 addErrCtxtM msg = updCtxt (\ msgs -> msg : msgs)
545 setErrCtxt, addErrCtxt :: Message -> TcM a -> TcM a
546 setErrCtxt msg = setErrCtxtM (\env -> returnM (env, msg))
547 addErrCtxt msg = addErrCtxtM (\env -> returnM (env, msg))
549 popErrCtxt :: TcM a -> TcM a
550 popErrCtxt = updCtxt (\ msgs -> case msgs of { [] -> []; (m:ms) -> ms })
552 getErrCtxt :: TcM ErrCtxt
553 getErrCtxt = do { env <- getLclEnv ; return (tcl_ctxt env) }
555 -- Helper function for the above
556 updCtxt :: (ErrCtxt -> ErrCtxt) -> TcM a -> TcM a
557 updCtxt upd = updLclEnv (\ env@(TcLclEnv { tcl_ctxt = ctxt }) ->
558 env { tcl_ctxt = upd ctxt })
560 getInstLoc :: InstOrigin -> TcM InstLoc
562 = do { loc <- getSrcLocM ; env <- getLclEnv ;
563 return (origin, loc, (tcl_ctxt env)) }
566 The addErr functions add an error message, but do not cause failure.
567 The 'M' variants pass a TidyEnv that has already been used to
568 tidy up the message; we then use it to tidy the context messages
571 addErrTc :: Message -> TcM ()
572 addErrTc err_msg = addErrTcM (emptyTidyEnv, err_msg)
574 addErrsTc :: [Message] -> TcM ()
575 addErrsTc err_msgs = mappM_ addErrTc err_msgs
577 addErrTcM :: (TidyEnv, Message) -> TcM ()
578 addErrTcM (tidy_env, err_msg)
579 = do { ctxt <- getErrCtxt ;
581 add_err_tcm tidy_env err_msg loc ctxt }
583 addInstErrTcM :: InstLoc -> (TidyEnv, Message) -> TcM ()
584 addInstErrTcM inst_loc@(_, loc, ctxt) (tidy_env, err_msg)
585 = add_err_tcm tidy_env err_msg loc full_ctxt
587 full_ctxt = (\env -> returnM (env, pprInstLoc inst_loc)) : ctxt
590 The failWith functions add an error message and cause failure
593 failWithTc :: Message -> TcM a -- Add an error message and fail
595 = addErrTc err_msg >> failM
597 failWithTcM :: (TidyEnv, Message) -> TcM a -- Add an error message and fail
598 failWithTcM local_and_msg
599 = addErrTcM local_and_msg >> failM
601 checkTc :: Bool -> Message -> TcM () -- Check that the boolean is true
602 checkTc True err = returnM ()
603 checkTc False err = failWithTc err
606 Warnings have no 'M' variant, nor failure
609 addWarnTc :: Message -> TcM ()
611 = do { ctxt <- getErrCtxt ;
612 ctxt_msgs <- do_ctxt emptyTidyEnv ctxt ;
613 addWarn (vcat (msg : ctxt_to_use ctxt_msgs)) }
615 warnTc :: Bool -> Message -> TcM ()
616 warnTc warn_if_true warn_msg
617 | warn_if_true = addWarnTc warn_msg
618 | otherwise = return ()
624 add_err_tcm tidy_env err_msg loc ctxt
625 = do { ctxt_msgs <- do_ctxt tidy_env ctxt ;
626 add_err loc (vcat (err_msg : ctxt_to_use ctxt_msgs)) }
630 do_ctxt tidy_env (c:cs)
631 = do { (tidy_env', m) <- c tidy_env ;
632 ms <- do_ctxt tidy_env' cs ;
635 ctxt_to_use ctxt | opt_PprStyle_Debug = ctxt
636 | otherwise = take 3 ctxt
639 %************************************************************************
641 Other stuff specific to type checker
643 %************************************************************************
646 getLIEVar :: TcM (TcRef LIE)
647 getLIEVar = do { env <- getLclEnv; return (tcl_lie env) }
649 setLIEVar :: TcRef LIE -> TcM a -> TcM a
650 setLIEVar lie_var = updLclEnv (\ env -> env { tcl_lie = lie_var })
652 getLIE :: TcM a -> TcM (a, [Inst])
653 -- (getLIE m) runs m, and returns the type constraints it generates
655 = do { lie_var <- newMutVar emptyLIE ;
656 res <- updLclEnv (\ env -> env { tcl_lie = lie_var })
658 lie <- readMutVar lie_var ;
659 return (res, lieToList lie) }
661 extendLIE :: Inst -> TcM ()
663 = do { lie_var <- getLIEVar ;
664 lie <- readMutVar lie_var ;
665 writeMutVar lie_var (inst `consLIE` lie) }
667 extendLIEs :: [Inst] -> TcM ()
671 = do { lie_var <- getLIEVar ;
672 lie <- readMutVar lie_var ;
673 writeMutVar lie_var (mkLIE insts `plusLIE` lie) }
678 getStage :: TcM Stage
679 getStage = do { env <- getLclEnv; return (tcl_level env) }
681 setStage :: Stage -> TcM a -> TcM a
682 setStage s = updLclEnv (\ env -> env { tcl_level = s })
684 setLclTypeEnv :: TcLclEnv -> TcM a -> TcM a
685 -- Set the local type envt, but do *not* disturb other fields,
686 -- notably the lie_var
687 setLclTypeEnv lcl_env thing_inside
688 = updLclEnv upd thing_inside
690 upd env = env { tcl_env = tcl_env lcl_env,
691 tcl_tyvars = tcl_tyvars lcl_env }
695 %************************************************************************
697 Stuff for the renamer's local env
699 %************************************************************************
702 initRn :: RnMode -> RnM a -> TcRn m a
703 initRn mode thing_inside
704 = do { env <- getGblEnv ;
705 let { lcl_env = RnLclEnv {
707 rn_lenv = emptyRdrEnv }} ;
708 setLclEnv lcl_env thing_inside }
712 getLocalRdrEnv :: RnM LocalRdrEnv
713 getLocalRdrEnv = do { env <- getLclEnv; return (rn_lenv env) }
715 setLocalRdrEnv :: LocalRdrEnv -> RnM a -> RnM a
716 setLocalRdrEnv rdr_env thing_inside
717 = updLclEnv (\env -> env {rn_lenv = rdr_env}) thing_inside
719 getModeRn :: RnM RnMode
720 getModeRn = do { env <- getLclEnv; return (rn_mode env) }