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, moduleName, 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 = init_imports,
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 init_imports = mkImportAvails (moduleName mod) True []
181 -- Initialise tcg_imports with an empty set of bindings for
182 -- this module, so that if we see 'module M' in the export
183 -- list, and there are no bindings in M, we don't bleat
184 -- "unknown module M".
187 defaultDefaultTys :: [Type]
188 defaultDefaultTys = [integerTy, doubleTy]
190 mkImpInstEnv :: DynFlags -> ExternalPackageState -> HomePackageTable -> InstEnv
191 mkImpInstEnv dflags eps hpt
192 = foldModuleEnv (add . md_insts . hm_details)
196 -- We shouldn't get instance conflict errors from
197 -- the package and home type envs
198 add dfuns inst_env = WARN( not (null errs), vcat (map snd errs) ) inst_env'
200 (inst_env', errs) = extendInstEnv dflags inst_env dfuns
202 -- mkImpTypeEnv makes the imported symbol table
203 mkImpTypeEnv :: ExternalPackageState -> HomePackageTable
204 -> Name -> Maybe TyThing
205 mkImpTypeEnv pcs hpt = lookup
208 lookup name | isInternalName name = Nothing
209 | otherwise = lookupType hpt pte name
213 %************************************************************************
217 %************************************************************************
220 getTopEnv :: TcRn m TopEnv
221 getTopEnv = do { env <- getEnv; return (env_top env) }
223 getGblEnv :: TcRn m TcGblEnv
224 getGblEnv = do { env <- getEnv; return (env_gbl env) }
226 updGblEnv :: (TcGblEnv -> TcGblEnv) -> TcRn m a -> TcRn m a
227 updGblEnv upd = updEnv (\ env@(Env { env_gbl = gbl }) ->
228 env { env_gbl = upd gbl })
230 setGblEnv :: TcGblEnv -> TcRn m a -> TcRn m a
231 setGblEnv gbl_env = updEnv (\ env -> env { env_gbl = gbl_env })
233 getLclEnv :: TcRn m m
234 getLclEnv = do { env <- getEnv; return (env_lcl env) }
236 updLclEnv :: (m -> m) -> TcRn m a -> TcRn m a
237 updLclEnv upd = updEnv (\ env@(Env { env_lcl = lcl }) ->
238 env { env_lcl = upd lcl })
240 setLclEnv :: m -> TcRn m a -> TcRn n a
241 setLclEnv lcl_env = updEnv (\ env -> env { env_lcl = lcl_env })
247 getDOpts :: TcRn m DynFlags
248 getDOpts = do { env <- getTopEnv; return (top_dflags env) }
250 doptM :: DynFlag -> TcRn m Bool
251 doptM flag = do { dflags <- getDOpts; return (dopt flag dflags) }
253 ifOptM :: DynFlag -> TcRn m () -> TcRn m () -- Do it flag is true
254 ifOptM flag thing_inside = do { b <- doptM flag;
255 if b then thing_inside else return () }
257 getGhciMode :: TcRn m GhciMode
258 getGhciMode = do { env <- getTopEnv; return (top_mode env) }
262 getSrcLocM :: TcRn m SrcLoc
263 -- Avoid clash with Name.getSrcLoc
264 getSrcLocM = do { env <- getEnv; return (env_loc env) }
266 addSrcLoc :: SrcLoc -> TcRn m a -> TcRn m a
267 addSrcLoc loc = updEnv (\env -> env { env_loc = loc })
271 getEps :: TcRn m ExternalPackageState
272 getEps = do { env <- getTopEnv; readMutVar (top_eps env) }
274 setEps :: ExternalPackageState -> TcRn m ()
275 setEps eps = do { env <- getTopEnv; writeMutVar (top_eps env) eps }
277 getHpt :: TcRn m HomePackageTable
278 getHpt = do { env <- getTopEnv; return (top_hpt env) }
280 getModule :: TcRn m Module
281 getModule = do { env <- getGblEnv; return (tcg_mod env) }
283 getGlobalRdrEnv :: TcRn m GlobalRdrEnv
284 getGlobalRdrEnv = do { env <- getGblEnv; return (tcg_rdr_env env) }
286 getFixityEnv :: TcRn m FixityEnv
287 getFixityEnv = do { env <- getGblEnv; return (tcg_fix_env env) }
289 extendFixityEnv :: [(Name,FixitySig Name)] -> RnM a -> RnM a
290 extendFixityEnv new_bit
291 = updGblEnv (\env@(TcGblEnv { tcg_fix_env = old_fix_env }) ->
292 env {tcg_fix_env = extendNameEnvList old_fix_env new_bit})
294 getDefaultTys :: TcRn m [Type]
295 getDefaultTys = do { env <- getGblEnv; return (tcg_default env) }
299 getUsageVar :: TcRn m (TcRef Usages)
300 getUsageVar = do { env <- getGblEnv; return (tcg_usages env) }
302 getUsages :: TcRn m Usages
303 getUsages = do { usg_var <- getUsageVar; readMutVar usg_var }
305 updUsages :: (Usages -> Usages) -> TcRn m ()
306 updUsages upd = do { usg_var <- getUsageVar ;
307 usg <- readMutVar usg_var ;
308 writeMutVar usg_var (upd usg) }
312 %************************************************************************
316 %************************************************************************
319 getErrsVar :: TcRn m (TcRef Messages)
320 getErrsVar = do { env <- getTopEnv; return (top_errs env) }
322 setErrsVar :: TcRef Messages -> TcRn m a -> TcRn m a
323 setErrsVar v = updEnv (\ env@(Env { env_top = top_env }) ->
324 env { env_top = top_env { top_errs = v }})
326 addErr :: Message -> TcRn m ()
327 addErr msg = do { loc <- getSrcLocM ; addErrAt loc msg }
329 addErrAt :: SrcLoc -> Message -> TcRn m ()
331 = do { errs_var <- getErrsVar ;
332 rdr_env <- getGlobalRdrEnv ;
333 let { err = addShortErrLocLine loc (unQualInScope rdr_env) msg } ;
334 (warns, errs) <- readMutVar errs_var ;
335 writeMutVar errs_var (warns, errs `snocBag` err) }
337 addErrs :: [(SrcLoc,Message)] -> TcRn m ()
338 addErrs msgs = mappM_ add msgs
340 add (loc,msg) = addErrAt loc msg
342 addWarn :: Message -> TcRn m ()
344 = do { errs_var <- getErrsVar ;
346 rdr_env <- getGlobalRdrEnv ;
347 let { warn = addShortWarnLocLine loc (unQualInScope rdr_env) msg } ;
348 (warns, errs) <- readMutVar errs_var ;
349 writeMutVar errs_var (warns `snocBag` warn, errs) }
351 checkErr :: Bool -> Message -> TcRn m ()
352 -- Add the error if the bool is False
353 checkErr ok msg = checkM ok (addErr msg)
355 warnIf :: Bool -> Message -> TcRn m ()
356 warnIf True msg = addWarn msg
357 warnIf False msg = return ()
359 addMessages :: Messages -> TcRn m ()
360 addMessages (m_warns, m_errs)
361 = do { errs_var <- getErrsVar ;
362 (warns, errs) <- readMutVar errs_var ;
363 writeMutVar errs_var (warns `unionBags` m_warns,
364 errs `unionBags` m_errs) }
366 checkGHCI :: Message -> TcRn m () -- Check that GHCI is on
367 -- otherwise add the error message
369 checkGHCI m = returnM ()
371 checkGHCI m = addErr m
377 recoverM :: TcRn m r -- Recovery action; do this if the main one fails
378 -> TcRn m r -- Main action: do this first
380 recoverM recover thing
381 = do { mb_res <- tryM thing ;
384 Right res -> returnM res }
386 tryTc :: TcRn m a -> TcRn m (Messages, Maybe a)
387 -- (tryTc m) executes m, and returns
388 -- Just r, if m succeeds (returning r) and caused no errors
389 -- Nothing, if m fails, or caused errors
390 -- It also returns all the errors accumulated by m
391 -- (even in the Just case, there might be warnings)
393 -- It always succeeds (never raises an exception)
395 = do { errs_var <- newMutVar emptyMessages ;
397 mb_r <- tryM (setErrsVar errs_var m) ;
399 new_errs <- readMutVar errs_var ;
404 Right r | errorsFound new_errs -> Nothing
405 | otherwise -> Just r)
408 tryTcLIE :: TcM a -> TcM (Messages, Maybe a)
409 -- Just like tryTc, except that it ensures that the LIE
410 -- for the thing is propagated only if there are no errors
411 -- Hence it's restricted to the type-check monad
412 tryTcLIE thing_inside
413 = do { ((errs, mb_r), lie) <- getLIE (tryTc thing_inside) ;
414 ifM (isJust mb_r) (extendLIEs lie) ;
415 return (errs, mb_r) }
417 tryTcLIE_ :: TcM r -> TcM r -> TcM r
418 -- (tryM_ r m) tries m; if it succeeds it returns it,
419 -- otherwise it returns r. Any error messages added by m are discarded,
420 -- whether or not m succeeds.
421 tryTcLIE_ recover main
422 = do { (_msgs, mb_res) <- tryTcLIE main ;
424 Just res -> return res
427 checkNoErrs :: TcM r -> TcM r
428 -- (checkNoErrs m) succeeds iff m succeeds and generates no errors
429 -- If m fails then (checkNoErrsTc m) fails.
430 -- If m succeeds, it checks whether m generated any errors messages
431 -- (it might have recovered internally)
432 -- If so, it fails too.
433 -- Regardless, any errors generated by m are propagated to the enclosing context.
435 = do { (msgs, mb_res) <- tryTcLIE main ;
442 ifErrsM :: TcRn m r -> TcRn m r -> TcRn m r
443 -- ifErrsM bale_out main
444 -- does 'bale_out' if there are errors in errors collection
445 -- otherwise does 'main'
446 ifErrsM bale_out normal
447 = do { errs_var <- getErrsVar ;
448 msgs <- readMutVar errs_var ;
449 if errorsFound msgs then
454 failIfErrsM :: TcRn m ()
455 -- Useful to avoid error cascades
456 failIfErrsM = ifErrsM failM (return ())
460 forkM :: SDoc -> TcM a -> TcM (Maybe a)
461 -- Run thing_inside in an interleaved thread. It gets a separate
464 -- but everything else is shared, so this is DANGEROUS.
466 -- It returns Nothing if the computation fails
468 -- It's used for lazily type-checking interface
469 -- signatures, which is pretty benign
471 forkM doc thing_inside
472 = do { us <- newUniqueSupply ;
474 do { us_var <- newMutVar us ;
475 (msgs, mb_res) <- tryTcLIE (setUsVar us_var thing_inside) ;
477 Just r -> return (Just r)
479 -- Bleat about errors in the forked thread
480 ioToTcRn (do { printErrs (hdr_doc defaultErrStyle) ;
481 printErrorsAndWarnings msgs }) ;
485 hdr_doc = text "forkM failed:" <+> doc
489 %************************************************************************
493 %************************************************************************
496 getUsVar :: TcRn m (TcRef UniqSupply)
497 getUsVar = do { env <- getTopEnv; return (top_us env) }
499 setUsVar :: TcRef UniqSupply -> TcRn m a -> TcRn m a
500 setUsVar v = updEnv (\ env@(Env { env_top = top_env }) ->
501 env { env_top = top_env { top_us = v }})
503 newUnique :: TcRn m Unique
504 newUnique = do { us <- newUniqueSupply ;
505 return (uniqFromSupply us) }
507 newUniqueSupply :: TcRn m UniqSupply
509 = do { u_var <- getUsVar ;
510 us <- readMutVar u_var ;
511 let { (us1, us2) = splitUniqSupply us } ;
512 writeMutVar u_var us1 ;
518 getNameCache :: TcRn m NameCache
519 getNameCache = do { TopEnv { top_nc = nc_var } <- getTopEnv;
522 setNameCache :: NameCache -> TcRn m ()
523 setNameCache nc = do { TopEnv { top_nc = nc_var } <- getTopEnv;
524 writeMutVar nc_var nc }
528 %************************************************************************
532 %************************************************************************
535 traceTc, traceRn :: SDoc -> TcRn a ()
536 traceRn = dumpOptTcRn Opt_D_dump_rn_trace
537 traceTc = dumpOptTcRn Opt_D_dump_tc_trace
538 traceSplice = dumpOptTcRn Opt_D_dump_splices
539 traceHiDiffs = dumpOptTcRn Opt_D_dump_hi_diffs
541 dumpOptTcRn :: DynFlag -> SDoc -> TcRn a ()
542 dumpOptTcRn flag doc = ifOptM flag (dumpTcRn doc)
544 dumpTcRn :: SDoc -> TcRn a ()
545 dumpTcRn doc = do { rdr_env <- getGlobalRdrEnv ;
546 ioToTcRn (printForUser stderr (unQualInScope rdr_env) doc) }
550 %************************************************************************
552 Context management and error message generation
555 %************************************************************************
558 setErrCtxtM, addErrCtxtM :: (TidyEnv -> TcM (TidyEnv, Message)) -> TcM a -> TcM a
559 setErrCtxtM msg = updCtxt (\ msgs -> [msg])
560 addErrCtxtM msg = updCtxt (\ msgs -> msg : msgs)
562 setErrCtxt, addErrCtxt :: Message -> TcM a -> TcM a
563 setErrCtxt msg = setErrCtxtM (\env -> returnM (env, msg))
564 addErrCtxt msg = addErrCtxtM (\env -> returnM (env, msg))
566 popErrCtxt :: TcM a -> TcM a
567 popErrCtxt = updCtxt (\ msgs -> case msgs of { [] -> []; (m:ms) -> ms })
569 getErrCtxt :: TcM ErrCtxt
570 getErrCtxt = do { env <- getLclEnv ; return (tcl_ctxt env) }
572 -- Helper function for the above
573 updCtxt :: (ErrCtxt -> ErrCtxt) -> TcM a -> TcM a
574 updCtxt upd = updLclEnv (\ env@(TcLclEnv { tcl_ctxt = ctxt }) ->
575 env { tcl_ctxt = upd ctxt })
577 getInstLoc :: InstOrigin -> TcM InstLoc
579 = do { loc <- getSrcLocM ; env <- getLclEnv ;
580 return (origin, loc, (tcl_ctxt env)) }
583 The addErrTc functions add an error message, but do not cause failure.
584 The 'M' variants pass a TidyEnv that has already been used to
585 tidy up the message; we then use it to tidy the context messages
588 addErrTc :: Message -> TcM ()
589 addErrTc err_msg = addErrTcM (emptyTidyEnv, err_msg)
591 addErrsTc :: [Message] -> TcM ()
592 addErrsTc err_msgs = mappM_ addErrTc err_msgs
594 addErrTcM :: (TidyEnv, Message) -> TcM ()
595 addErrTcM (tidy_env, err_msg)
596 = do { ctxt <- getErrCtxt ;
598 add_err_tcm tidy_env err_msg loc ctxt }
600 addInstErrTcM :: InstLoc -> (TidyEnv, Message) -> TcM ()
601 addInstErrTcM inst_loc@(_, loc, ctxt) (tidy_env, err_msg)
602 = add_err_tcm tidy_env err_msg loc full_ctxt
604 full_ctxt = (\env -> returnM (env, pprInstLoc inst_loc)) : ctxt
607 The failWith functions add an error message and cause failure
610 failWithTc :: Message -> TcM a -- Add an error message and fail
612 = addErrTc err_msg >> failM
614 failWithTcM :: (TidyEnv, Message) -> TcM a -- Add an error message and fail
615 failWithTcM local_and_msg
616 = addErrTcM local_and_msg >> failM
618 checkTc :: Bool -> Message -> TcM () -- Check that the boolean is true
619 checkTc True err = returnM ()
620 checkTc False err = failWithTc err
623 Warnings have no 'M' variant, nor failure
626 addWarnTc :: Message -> TcM ()
628 = do { ctxt <- getErrCtxt ;
629 ctxt_msgs <- do_ctxt emptyTidyEnv ctxt ;
630 addWarn (vcat (msg : ctxt_to_use ctxt_msgs)) }
632 warnTc :: Bool -> Message -> TcM ()
633 warnTc warn_if_true warn_msg
634 | warn_if_true = addWarnTc warn_msg
635 | otherwise = return ()
641 add_err_tcm tidy_env err_msg loc ctxt
642 = do { ctxt_msgs <- do_ctxt tidy_env ctxt ;
643 addErrAt loc (vcat (err_msg : ctxt_to_use ctxt_msgs)) }
647 do_ctxt tidy_env (c:cs)
648 = do { (tidy_env', m) <- c tidy_env ;
649 ms <- do_ctxt tidy_env' cs ;
652 ctxt_to_use ctxt | opt_PprStyle_Debug = ctxt
653 | otherwise = take 3 ctxt
656 %************************************************************************
658 Other stuff specific to type checker
660 %************************************************************************
663 getLIEVar :: TcM (TcRef LIE)
664 getLIEVar = do { env <- getLclEnv; return (tcl_lie env) }
666 setLIEVar :: TcRef LIE -> TcM a -> TcM a
667 setLIEVar lie_var = updLclEnv (\ env -> env { tcl_lie = lie_var })
669 getLIE :: TcM a -> TcM (a, [Inst])
670 -- (getLIE m) runs m, and returns the type constraints it generates
672 = do { lie_var <- newMutVar emptyLIE ;
673 res <- updLclEnv (\ env -> env { tcl_lie = lie_var })
675 lie <- readMutVar lie_var ;
676 return (res, lieToList lie) }
678 extendLIE :: Inst -> TcM ()
680 = do { lie_var <- getLIEVar ;
681 lie <- readMutVar lie_var ;
682 writeMutVar lie_var (inst `consLIE` lie) }
684 extendLIEs :: [Inst] -> TcM ()
688 = do { lie_var <- getLIEVar ;
689 lie <- readMutVar lie_var ;
690 writeMutVar lie_var (mkLIE insts `plusLIE` lie) }
695 getStage :: TcM Stage
696 getStage = do { env <- getLclEnv; return (tcl_level env) }
698 setStage :: Stage -> TcM a -> TcM a
699 setStage s = updLclEnv (\ env -> env { tcl_level = s })
701 setLclTypeEnv :: TcLclEnv -> TcM a -> TcM a
702 -- Set the local type envt, but do *not* disturb other fields,
703 -- notably the lie_var
704 setLclTypeEnv lcl_env thing_inside
705 = updLclEnv upd thing_inside
707 upd env = env { tcl_env = tcl_env lcl_env,
708 tcl_tyvars = tcl_tyvars lcl_env }
712 %************************************************************************
714 Stuff for the renamer's local env
716 %************************************************************************
719 initRn :: RnMode -> RnM a -> TcRn m a
720 initRn mode thing_inside
721 = do { env <- getGblEnv ;
722 let { lcl_env = RnLclEnv {
724 rn_lenv = emptyRdrEnv }} ;
725 setLclEnv lcl_env thing_inside }
729 getLocalRdrEnv :: RnM LocalRdrEnv
730 getLocalRdrEnv = do { env <- getLclEnv; return (rn_lenv env) }
732 setLocalRdrEnv :: LocalRdrEnv -> RnM a -> RnM a
733 setLocalRdrEnv rdr_env thing_inside
734 = updLclEnv (\env -> env {rn_lenv = rdr_env}) thing_inside
736 getModeRn :: RnM RnMode
737 getModeRn = do { env <- getLclEnv; return (rn_mode env) }