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, unitModuleEnv, 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 )
38 import Panic ( showException )
40 import Maybe ( isJust )
42 import DATA_IOREF ( newIORef, readIORef )
43 import EXCEPTION ( Exception )
46 %************************************************************************
48 Standard combinators, but specialised for this monad
51 6%************************************************************************
54 mappM :: (a -> TcRn m b) -> [a] -> TcRn m [b]
55 mappM_ :: (a -> TcRn m b) -> [a] -> TcRn m ()
56 -- Funny names to avoid clash with Prelude
57 sequenceM :: [TcRn m a] -> TcRn m [a]
58 foldlM :: (a -> b -> TcRn m a) -> a -> [b] -> TcRn m a
59 mapAndUnzipM :: (a -> TcRn m (b,c)) -> [a] -> TcRn m ([b],[c])
60 mapAndUnzip3M :: (a -> TcRn m (b,c,d)) -> [a] -> TcRn m ([b],[c],[d])
61 checkM :: Bool -> TcRn m () -> TcRn m () -- Perform arg if bool is False
62 ifM :: Bool -> TcRn m () -> TcRn m () -- Perform arg if bool is True
64 mappM f [] = return []
65 mappM f (x:xs) = do { r <- f x; rs <- mappM f xs; return (r:rs) }
67 mappM_ f [] = return ()
68 mappM_ f (x:xs) = f x >> mappM_ f xs
70 sequenceM [] = return []
71 sequenceM (x:xs) = do { r <- x; rs <- sequenceM xs; return (r:rs) }
73 foldlM k z [] = return z
74 foldlM k z (x:xs) = do { r <- k z x; foldlM k r xs }
76 mapAndUnzipM f [] = return ([],[])
77 mapAndUnzipM f (x:xs) = do { (r,s) <- f x;
78 (rs,ss) <- mapAndUnzipM f xs;
81 mapAndUnzip3M f [] = return ([],[], [])
82 mapAndUnzip3M f (x:xs) = do { (r,s,t) <- f x;
83 (rs,ss,ts) <- mapAndUnzip3M f xs;
84 return (r:rs, s:ss, t:ts) }
86 checkM True err = return ()
87 checkM False err = err
89 ifM True do_it = do_it
90 ifM False do_it = return ()
94 %************************************************************************
98 %************************************************************************
101 initTc :: HscEnv -> PersistentCompilerState
104 -> IO (PersistentCompilerState, Maybe r)
105 -- Nothing => error thrown by the thing inside
106 -- (error messages should have been printed already)
108 initTc (HscEnv { hsc_mode = ghci_mode,
110 hsc_dflags = dflags })
112 = do { us <- mkSplitUniqSupply 'a' ;
113 us_var <- newIORef us ;
114 errs_var <- newIORef (emptyBag, emptyBag) ;
115 tvs_var <- newIORef emptyVarSet ;
116 usg_var <- newIORef emptyUsages ;
117 nc_var <- newIORef (pcs_nc pcs) ;
118 eps_var <- newIORef eps ;
119 ie_var <- newIORef (mkImpInstEnv dflags eps hpt) ;
122 env = Env { env_top = top_env,
125 env_loc = noSrcLoc } ;
128 top_mode = ghci_mode,
134 top_errs = errs_var } ;
138 tcg_usages = usg_var,
139 tcg_rdr_env = emptyGlobalRdrEnv,
140 tcg_fix_env = emptyFixityEnv,
141 tcg_default = defaultDefaultTys,
142 tcg_type_env = emptyNameEnv,
143 tcg_inst_env = ie_var,
145 tcg_imports = init_imports,
146 tcg_binds = EmptyMonoBinds,
147 tcg_deprecs = NoDeprecs,
154 tcl_level = topStage,
155 tcl_env = emptyNameEnv,
156 tcl_tyvars = tvs_var,
157 tcl_lie = panic "initTc:LIE" } ;
158 -- LIE only valid inside a getLIE
161 -- OK, here's the business end!
162 maybe_res <- catch (do { res <- runTcRn env do_this ;
164 (\_ -> return Nothing) ;
166 -- Print any error messages
167 msgs <- readIORef errs_var ;
168 printErrorsAndWarnings msgs ;
170 -- Get final PCS and return
171 eps' <- readIORef eps_var ;
172 nc' <- readIORef nc_var ;
173 let { pcs' = PCS { pcs_EPS = eps', pcs_nc = nc' } ;
174 final_res | errorsFound dflags msgs = Nothing
175 | otherwise = maybe_res } ;
177 return (pcs', final_res)
182 init_imports = emptyImportAvails { imp_qual = unitModuleEnv mod emptyAvailEnv }
183 -- Initialise tcg_imports with an empty set of bindings for
184 -- this module, so that if we see 'module M' in the export
185 -- list, and there are no bindings in M, we don't bleat
186 -- "unknown module M".
188 defaultDefaultTys :: [Type]
189 defaultDefaultTys = [integerTy, doubleTy]
191 mkImpInstEnv :: DynFlags -> ExternalPackageState -> HomePackageTable -> InstEnv
192 -- At the moment we (wrongly) build an instance environment from all the
193 -- modules we have already compiled:
194 -- (a) eps_inst_env from the external package state
195 -- (b) all the md_insts in the home package table
196 -- We should really only get instances from modules below us in the
197 -- module import tree.
198 mkImpInstEnv dflags eps hpt
199 = foldModuleEnv (add . md_insts . hm_details)
203 -- We shouldn't get instance conflict errors from
204 -- the package and home type envs
205 add dfuns inst_env = WARN( not (null errs), vcat (map snd errs) ) inst_env'
207 (inst_env', errs) = extendInstEnv dflags inst_env dfuns
209 -- mkImpTypeEnv makes the imported symbol table
210 mkImpTypeEnv :: ExternalPackageState -> HomePackageTable
211 -> Name -> Maybe TyThing
212 mkImpTypeEnv pcs hpt = lookup
215 lookup name | isInternalName name = Nothing
216 | otherwise = lookupType hpt pte name
220 %************************************************************************
224 %************************************************************************
227 getTopEnv :: TcRn m TopEnv
228 getTopEnv = do { env <- getEnv; return (env_top env) }
230 getGblEnv :: TcRn m TcGblEnv
231 getGblEnv = do { env <- getEnv; return (env_gbl env) }
233 updGblEnv :: (TcGblEnv -> TcGblEnv) -> TcRn m a -> TcRn m a
234 updGblEnv upd = updEnv (\ env@(Env { env_gbl = gbl }) ->
235 env { env_gbl = upd gbl })
237 setGblEnv :: TcGblEnv -> TcRn m a -> TcRn m a
238 setGblEnv gbl_env = updEnv (\ env -> env { env_gbl = gbl_env })
240 getLclEnv :: TcRn m m
241 getLclEnv = do { env <- getEnv; return (env_lcl env) }
243 updLclEnv :: (m -> m) -> TcRn m a -> TcRn m a
244 updLclEnv upd = updEnv (\ env@(Env { env_lcl = lcl }) ->
245 env { env_lcl = upd lcl })
247 setLclEnv :: m -> TcRn m a -> TcRn n a
248 setLclEnv lcl_env = updEnv (\ env -> env { env_lcl = lcl_env })
250 getEnvs :: TcRn m (TcGblEnv, m)
251 getEnvs = do { env <- getEnv; return (env_gbl env, env_lcl env) }
253 setEnvs :: (TcGblEnv, m) -> TcRn m a -> TcRn m a
254 setEnvs (gbl_env, lcl_env) = updEnv (\ env -> env { env_gbl = gbl_env, env_lcl = lcl_env })
260 getDOpts :: TcRn m DynFlags
261 getDOpts = do { env <- getTopEnv; return (top_dflags env) }
263 doptM :: DynFlag -> TcRn m Bool
264 doptM flag = do { dflags <- getDOpts; return (dopt flag dflags) }
266 ifOptM :: DynFlag -> TcRn m () -> TcRn m () -- Do it flag is true
267 ifOptM flag thing_inside = do { b <- doptM flag;
268 if b then thing_inside else return () }
270 getGhciMode :: TcRn m GhciMode
271 getGhciMode = do { env <- getTopEnv; return (top_mode env) }
275 getSrcLocM :: TcRn m SrcLoc
276 -- Avoid clash with Name.getSrcLoc
277 getSrcLocM = do { env <- getEnv; return (env_loc env) }
279 addSrcLoc :: SrcLoc -> TcRn m a -> TcRn m a
280 addSrcLoc loc = updEnv (\env -> env { env_loc = loc })
284 getEps :: TcRn m ExternalPackageState
285 getEps = do { env <- getTopEnv; readMutVar (top_eps env) }
287 setEps :: ExternalPackageState -> TcRn m ()
288 setEps eps = do { env <- getTopEnv; writeMutVar (top_eps env) eps }
290 getHpt :: TcRn m HomePackageTable
291 getHpt = do { env <- getTopEnv; return (top_hpt env) }
293 getModule :: TcRn m Module
294 getModule = do { env <- getGblEnv; return (tcg_mod env) }
296 getGlobalRdrEnv :: TcRn m GlobalRdrEnv
297 getGlobalRdrEnv = do { env <- getGblEnv; return (tcg_rdr_env env) }
299 getImports :: TcRn m ImportAvails
300 getImports = do { env <- getGblEnv; return (tcg_imports env) }
302 getFixityEnv :: TcRn m FixityEnv
303 getFixityEnv = do { env <- getGblEnv; return (tcg_fix_env env) }
305 extendFixityEnv :: [(Name,FixitySig Name)] -> RnM a -> RnM a
306 extendFixityEnv new_bit
307 = updGblEnv (\env@(TcGblEnv { tcg_fix_env = old_fix_env }) ->
308 env {tcg_fix_env = extendNameEnvList old_fix_env new_bit})
310 getDefaultTys :: TcRn m [Type]
311 getDefaultTys = do { env <- getGblEnv; return (tcg_default env) }
315 getUsageVar :: TcRn m (TcRef EntityUsage)
316 getUsageVar = do { env <- getGblEnv; return (tcg_usages env) }
318 getUsages :: TcRn m EntityUsage
319 getUsages = do { usg_var <- getUsageVar; readMutVar usg_var }
321 updUsages :: (EntityUsage -> EntityUsage) -> TcRn m ()
322 updUsages upd = do { usg_var <- getUsageVar ;
323 usg <- readMutVar usg_var ;
324 writeMutVar usg_var (upd usg) }
328 %************************************************************************
332 %************************************************************************
335 getErrsVar :: TcRn m (TcRef Messages)
336 getErrsVar = do { env <- getTopEnv; return (top_errs env) }
338 setErrsVar :: TcRef Messages -> TcRn m a -> TcRn m a
339 setErrsVar v = updEnv (\ env@(Env { env_top = top_env }) ->
340 env { env_top = top_env { top_errs = v }})
342 addErr :: Message -> TcRn m ()
343 addErr msg = do { loc <- getSrcLocM ; addErrAt loc msg }
345 addErrAt :: SrcLoc -> Message -> TcRn m ()
347 = do { errs_var <- getErrsVar ;
348 rdr_env <- getGlobalRdrEnv ;
349 let { err = addShortErrLocLine loc (unQualInScope rdr_env) msg } ;
350 (warns, errs) <- readMutVar errs_var ;
351 writeMutVar errs_var (warns, errs `snocBag` err) }
353 addErrs :: [(SrcLoc,Message)] -> TcRn m ()
354 addErrs msgs = mappM_ add msgs
356 add (loc,msg) = addErrAt loc msg
358 addWarn :: Message -> TcRn m ()
360 = do { errs_var <- getErrsVar ;
362 rdr_env <- getGlobalRdrEnv ;
363 let { warn = addShortWarnLocLine loc (unQualInScope rdr_env) msg } ;
364 (warns, errs) <- readMutVar errs_var ;
365 writeMutVar errs_var (warns `snocBag` warn, errs) }
367 checkErr :: Bool -> Message -> TcRn m ()
368 -- Add the error if the bool is False
369 checkErr ok msg = checkM ok (addErr msg)
371 warnIf :: Bool -> Message -> TcRn m ()
372 warnIf True msg = addWarn msg
373 warnIf False msg = return ()
375 addMessages :: Messages -> TcRn m ()
376 addMessages (m_warns, m_errs)
377 = do { errs_var <- getErrsVar ;
378 (warns, errs) <- readMutVar errs_var ;
379 writeMutVar errs_var (warns `unionBags` m_warns,
380 errs `unionBags` m_errs) }
385 recoverM :: TcRn m r -- Recovery action; do this if the main one fails
386 -> TcRn m r -- Main action: do this first
388 recoverM recover thing
389 = do { mb_res <- try_m thing ;
392 Right res -> returnM res }
394 tryTc :: TcRn m a -> TcRn m (Messages, Maybe a)
395 -- (tryTc m) executes m, and returns
396 -- Just r, if m succeeds (returning r) and caused no errors
397 -- Nothing, if m fails, or caused errors
398 -- It also returns all the errors accumulated by m
399 -- (even in the Just case, there might be warnings)
401 -- It always succeeds (never raises an exception)
403 = do { errs_var <- newMutVar emptyMessages ;
405 mb_r <- try_m (setErrsVar errs_var m) ;
407 new_errs <- readMutVar errs_var ;
414 Right r | errorsFound dflags new_errs -> Nothing
415 | otherwise -> Just r)
418 try_m :: TcRn m r -> TcRn m (Either Exception r)
419 -- Does try_m, with a debug-trace on failure
421 = do { mb_r <- tryM thing ;
423 Left exn -> do { traceTc (exn_msg exn); return mb_r }
424 Right r -> return mb_r }
426 exn_msg exn = text "recoverM recovering from" <+> text (showException exn)
428 tryTcLIE :: TcM a -> TcM (Messages, Maybe a)
429 -- Just like tryTc, except that it ensures that the LIE
430 -- for the thing is propagated only if there are no errors
431 -- Hence it's restricted to the type-check monad
432 tryTcLIE thing_inside
433 = do { ((errs, mb_r), lie) <- getLIE (tryTc thing_inside) ;
434 ifM (isJust mb_r) (extendLIEs lie) ;
435 return (errs, mb_r) }
437 tryTcLIE_ :: TcM r -> TcM r -> TcM r
438 -- (tryTcLIE_ r m) tries m; if it succeeds it returns it,
439 -- otherwise it returns r. Any error messages added by m are discarded,
440 -- whether or not m succeeds.
441 tryTcLIE_ recover main
442 = do { (_msgs, mb_res) <- tryTcLIE main ;
444 Just res -> return res
447 checkNoErrs :: TcM r -> TcM r
448 -- (checkNoErrs m) succeeds iff m succeeds and generates no errors
449 -- If m fails then (checkNoErrsTc m) fails.
450 -- If m succeeds, it checks whether m generated any errors messages
451 -- (it might have recovered internally)
452 -- If so, it fails too.
453 -- Regardless, any errors generated by m are propagated to the enclosing context.
455 = do { (msgs, mb_res) <- tryTcLIE main ;
462 ifErrsM :: TcRn m r -> TcRn m r -> TcRn m r
463 -- ifErrsM bale_out main
464 -- does 'bale_out' if there are errors in errors collection
465 -- otherwise does 'main'
466 ifErrsM bale_out normal
467 = do { errs_var <- getErrsVar ;
468 msgs <- readMutVar errs_var ;
470 if errorsFound dflags msgs then
475 failIfErrsM :: TcRn m ()
476 -- Useful to avoid error cascades
477 failIfErrsM = ifErrsM failM (return ())
481 forkM :: SDoc -> TcM a -> TcM (Maybe a)
482 -- Run thing_inside in an interleaved thread. It gets a separate
485 -- * LIE var is set to bottom (should never be used)
486 -- but everything else is shared, so this is DANGEROUS.
488 -- It returns Nothing if the computation fails
490 -- It's used for lazily type-checking interface
491 -- signatures, which is pretty benign
493 forkM doc thing_inside
494 = do { us <- newUniqueSupply ;
496 do { us_var <- newMutVar us ;
497 (msgs, mb_res) <- tryTc (setLIEVar (panic "forkM: LIE used") $
498 setUsVar us_var thing_inside) ;
500 Just r -> return (Just r)
503 -- Bleat about errors in the forked thread, if -ddump-tc-trace is on
504 -- Otherwise we silently discard errors. Errors can legitimately
505 -- happen when compiling interface signatures (see tcInterfaceSigs)
506 ifOptM Opt_D_dump_tc_trace
507 (ioToTcRn (do { printErrs (hdr_doc defaultErrStyle) ;
508 printErrorsAndWarnings msgs })) ;
513 hdr_doc = text "forkM failed:" <+> doc
517 %************************************************************************
521 %************************************************************************
524 getUsVar :: TcRn m (TcRef UniqSupply)
525 getUsVar = do { env <- getTopEnv; return (top_us env) }
527 setUsVar :: TcRef UniqSupply -> TcRn m a -> TcRn m a
528 setUsVar v = updEnv (\ env@(Env { env_top = top_env }) ->
529 env { env_top = top_env { top_us = v }})
531 newUnique :: TcRn m Unique
532 newUnique = do { us <- newUniqueSupply ;
533 return (uniqFromSupply us) }
535 newUniqueSupply :: TcRn m UniqSupply
537 = do { u_var <- getUsVar ;
538 us <- readMutVar u_var ;
539 let { (us1, us2) = splitUniqSupply us } ;
540 writeMutVar u_var us1 ;
546 getNameCache :: TcRn m NameCache
547 getNameCache = do { TopEnv { top_nc = nc_var } <- getTopEnv;
550 setNameCache :: NameCache -> TcRn m ()
551 setNameCache nc = do { TopEnv { top_nc = nc_var } <- getTopEnv;
552 writeMutVar nc_var nc }
556 %************************************************************************
560 %************************************************************************
563 traceTc, traceRn :: SDoc -> TcRn a ()
564 traceRn = dumpOptTcRn Opt_D_dump_rn_trace
565 traceTc = dumpOptTcRn Opt_D_dump_tc_trace
566 traceSplice = dumpOptTcRn Opt_D_dump_splices
567 traceHiDiffs = dumpOptTcRn Opt_D_dump_hi_diffs
569 dumpOptTcRn :: DynFlag -> SDoc -> TcRn a ()
570 dumpOptTcRn flag doc = ifOptM flag (dumpTcRn doc)
572 dumpTcRn :: SDoc -> TcRn a ()
573 dumpTcRn doc = do { rdr_env <- getGlobalRdrEnv ;
574 ioToTcRn (printForUser stderr (unQualInScope rdr_env) doc) }
578 %************************************************************************
580 Context management and error message generation
583 %************************************************************************
586 setErrCtxtM, addErrCtxtM :: (TidyEnv -> TcM (TidyEnv, Message)) -> TcM a -> TcM a
587 setErrCtxtM msg = updCtxt (\ msgs -> [msg])
588 addErrCtxtM msg = updCtxt (\ msgs -> msg : msgs)
590 setErrCtxt, addErrCtxt :: Message -> TcM a -> TcM a
591 setErrCtxt msg = setErrCtxtM (\env -> returnM (env, msg))
592 addErrCtxt msg = addErrCtxtM (\env -> returnM (env, msg))
594 popErrCtxt :: TcM a -> TcM a
595 popErrCtxt = updCtxt (\ msgs -> case msgs of { [] -> []; (m:ms) -> ms })
597 getErrCtxt :: TcM ErrCtxt
598 getErrCtxt = do { env <- getLclEnv ; return (tcl_ctxt env) }
600 -- Helper function for the above
601 updCtxt :: (ErrCtxt -> ErrCtxt) -> TcM a -> TcM a
602 updCtxt upd = updLclEnv (\ env@(TcLclEnv { tcl_ctxt = ctxt }) ->
603 env { tcl_ctxt = upd ctxt })
605 getInstLoc :: InstOrigin -> TcM InstLoc
607 = do { loc <- getSrcLocM ; env <- getLclEnv ;
608 return (InstLoc origin loc (tcl_ctxt env)) }
610 addInstCtxt :: InstLoc -> TcM a -> TcM a
611 -- Add the SrcLoc and context from the first Inst in the list
612 -- (they all have similar locations)
613 addInstCtxt (InstLoc _ src_loc ctxt) thing_inside
614 = addSrcLoc src_loc (updCtxt (\ old_ctxt -> ctxt) thing_inside)
617 The addErrTc functions add an error message, but do not cause failure.
618 The 'M' variants pass a TidyEnv that has already been used to
619 tidy up the message; we then use it to tidy the context messages
622 addErrTc :: Message -> TcM ()
623 addErrTc err_msg = addErrTcM (emptyTidyEnv, err_msg)
625 addErrsTc :: [Message] -> TcM ()
626 addErrsTc err_msgs = mappM_ addErrTc err_msgs
628 addErrTcM :: (TidyEnv, Message) -> TcM ()
629 addErrTcM (tidy_env, err_msg)
630 = do { ctxt <- getErrCtxt ;
632 add_err_tcm tidy_env err_msg loc ctxt }
635 The failWith functions add an error message and cause failure
638 failWithTc :: Message -> TcM a -- Add an error message and fail
640 = addErrTc err_msg >> failM
642 failWithTcM :: (TidyEnv, Message) -> TcM a -- Add an error message and fail
643 failWithTcM local_and_msg
644 = addErrTcM local_and_msg >> failM
646 checkTc :: Bool -> Message -> TcM () -- Check that the boolean is true
647 checkTc True err = returnM ()
648 checkTc False err = failWithTc err
651 Warnings have no 'M' variant, nor failure
654 addWarnTc :: Message -> TcM ()
656 = do { ctxt <- getErrCtxt ;
657 ctxt_msgs <- do_ctxt emptyTidyEnv ctxt ;
658 addWarn (vcat (msg : ctxt_to_use ctxt_msgs)) }
660 warnTc :: Bool -> Message -> TcM ()
661 warnTc warn_if_true warn_msg
662 | warn_if_true = addWarnTc warn_msg
663 | otherwise = return ()
669 add_err_tcm tidy_env err_msg loc ctxt
670 = do { ctxt_msgs <- do_ctxt tidy_env ctxt ;
671 addErrAt loc (vcat (err_msg : ctxt_to_use ctxt_msgs)) }
675 do_ctxt tidy_env (c:cs)
676 = do { (tidy_env', m) <- c tidy_env ;
677 ms <- do_ctxt tidy_env' cs ;
680 ctxt_to_use ctxt | opt_PprStyle_Debug = ctxt
681 | otherwise = take 3 ctxt
684 %************************************************************************
686 Other stuff specific to type checker
688 %************************************************************************
691 getLIEVar :: TcM (TcRef LIE)
692 getLIEVar = do { env <- getLclEnv; return (tcl_lie env) }
694 setLIEVar :: TcRef LIE -> TcM a -> TcM a
695 setLIEVar lie_var = updLclEnv (\ env -> env { tcl_lie = lie_var })
697 getLIE :: TcM a -> TcM (a, [Inst])
698 -- (getLIE m) runs m, and returns the type constraints it generates
700 = do { lie_var <- newMutVar emptyLIE ;
701 res <- updLclEnv (\ env -> env { tcl_lie = lie_var })
703 lie <- readMutVar lie_var ;
704 return (res, lieToList lie) }
706 extendLIE :: Inst -> TcM ()
708 = do { lie_var <- getLIEVar ;
709 lie <- readMutVar lie_var ;
710 writeMutVar lie_var (inst `consLIE` lie) }
712 extendLIEs :: [Inst] -> TcM ()
716 = do { lie_var <- getLIEVar ;
717 lie <- readMutVar lie_var ;
718 writeMutVar lie_var (mkLIE insts `plusLIE` lie) }
723 getStage :: TcM Stage
724 getStage = do { env <- getLclEnv; return (tcl_level env) }
726 setStage :: Stage -> TcM a -> TcM a
727 setStage s = updLclEnv (\ env -> env { tcl_level = s })
729 setLclTypeEnv :: TcLclEnv -> TcM a -> TcM a
730 -- Set the local type envt, but do *not* disturb other fields,
731 -- notably the lie_var
732 setLclTypeEnv lcl_env thing_inside
733 = updLclEnv upd thing_inside
735 upd env = env { tcl_env = tcl_env lcl_env,
736 tcl_tyvars = tcl_tyvars lcl_env }
740 %************************************************************************
742 Stuff for the renamer's local env
744 %************************************************************************
747 initRn :: RnMode -> RnM a -> TcRn m a
748 initRn mode thing_inside
749 = do { env <- getGblEnv ;
750 let { lcl_env = RnLclEnv {
752 rn_lenv = emptyRdrEnv }} ;
753 setLclEnv lcl_env thing_inside }
757 getLocalRdrEnv :: RnM LocalRdrEnv
758 getLocalRdrEnv = do { env <- getLclEnv; return (rn_lenv env) }
760 setLocalRdrEnv :: LocalRdrEnv -> RnM a -> RnM a
761 setLocalRdrEnv rdr_env thing_inside
762 = updLclEnv (\env -> env {rn_lenv = rdr_env}) thing_inside
764 getModeRn :: RnM RnMode
765 getModeRn = do { env <- getLclEnv; return (rn_mode env) }