2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
4 \section[RnMonad]{The monad used by the renamer}
10 module RdrName, -- Re-exports
11 module Name, -- from these two
24 #include "HsVersions.h"
26 #if defined(__GLASGOW_HASKELL__) && __GLASGOW_HASKELL__ >= 405
27 import IOExts ( fixIO )
28 #elif defined(__GLASGOW_HASKELL__) && __GLASGOW_HASKELL__ >= 302
29 import PrelIOBase ( fixIO ) -- Should be in GlaExts
31 import IOBase ( fixIO )
33 import IOExts ( IORef, newIORef, readIORef, writeIORef, unsafePerformIO )
37 import RnHsSyn ( RenamedFixitySig )
38 import HscTypes ( Finder,
39 AvailEnv, lookupTypeEnv,
40 OrigNameEnv(..), OrigNameNameEnv, OrigNameIParamEnv,
41 WhetherHasOrphans, ImportVersion,
42 PersistentRenamerState(..), IsBootInterface, Avails,
43 DeclsMap, IfaceInsts, IfaceRules,
44 HomeSymbolTable, PackageSymbolTable,
45 PersistentCompilerState(..), GlobalRdrEnv,
46 HomeIfaceTable, PackageIfaceTable,
47 RdrAvailInfo, ModIface )
48 import BasicTypes ( Version, defaultFixity )
49 import ErrUtils ( addShortErrLocLine, addShortWarnLocLine,
50 pprBagOfErrors, ErrMsg, WarnMsg, Message
52 import RdrName ( RdrName, dummyRdrVarName, rdrNameModule, rdrNameOcc,
53 RdrNameEnv, emptyRdrEnv, extendRdrEnv,
54 addListToRdrEnv, rdrEnvToList, rdrEnvElts
56 import Name ( Name, OccName, NamedThing(..), getSrcLoc,
57 isLocallyDefinedName, nameModule, nameOccName,
58 decode, mkLocalName, mkKnownKeyGlobal,
59 NameEnv, lookupNameEnv, emptyNameEnv, unitNameEnv,
62 import Module ( Module, ModuleName, lookupModuleEnvByName )
64 import CmdLineOpts ( DynFlags, DynFlag(..), dopt )
65 import SrcLoc ( SrcLoc, generatedSrcLoc )
66 import Unique ( Unique )
67 import FiniteMap ( FiniteMap, emptyFM )
68 import Bag ( Bag, emptyBag, isEmptyBag, snocBag )
71 import PrelNames ( mkUnboundName )
72 import Maybes ( maybeToBool, seqMaybe, orElse )
74 infixr 9 `thenRn`, `thenRn_`
78 %************************************************************************
80 \subsection{Somewhat magical interface to other monads}
82 %************************************************************************
85 ioToRnM :: IO r -> RnM d (Either IOError r)
86 ioToRnM io rn_down g_down = (io >>= \ ok -> return (Right ok))
88 (\ err -> return (Left err))
90 traceRn :: SDoc -> RnM d ()
92 = doptRn Opt_D_dump_rn_trace `thenRn` \b ->
93 if b then putDocRn msg else returnRn ()
95 putDocRn :: SDoc -> RnM d ()
96 putDocRn msg = ioToRnM (printErrs msg) `thenRn_`
101 %************************************************************************
103 \subsection{Data types}
105 %************************************************************************
107 %===================================================
108 \subsubsection{ MONAD TYPES}
109 %===================================================
112 type RnM d r = RnDown -> d -> IO r
113 type RnMS r = RnM SDown r -- Renaming source
114 type RnMG r = RnM () r -- Getting global names etc
119 rn_mod :: Module, -- This module
120 rn_loc :: SrcLoc, -- Current locn
123 rn_dflags :: DynFlags,
125 rn_hit :: HomeIfaceTable,
126 rn_done :: Name -> Bool, -- Tells what things (both in the
127 -- home package and other packages)
128 -- were already available (i.e. in
129 -- the relevant SymbolTable) before
130 -- compiling this module
132 rn_errs :: IORef (Bag WarnMsg, Bag ErrMsg),
134 -- The second and third components are a flattened-out OrigNameEnv
135 rn_ns :: IORef (UniqSupply, OrigNameNameEnv, OrigNameIParamEnv),
136 rn_ifaces :: IORef Ifaces
139 -- For renaming source code
143 rn_genv :: GlobalRdrEnv, -- Global envt
145 rn_lenv :: LocalRdrEnv, -- Local name envt
146 -- Does *not* include global name envt; may shadow it
147 -- Includes both ordinary variables and type variables;
148 -- they are kept distinct because tyvar have a different
149 -- occurrence contructor (Name.TvOcc)
150 -- We still need the unsullied global name env so that
151 -- we can look up record field names
153 rn_fixenv :: LocalFixityEnv -- Local fixities
154 -- The global fixities are held in the
155 -- rn_ifaces field. Why? See the comments
156 -- with RnIfaces.lookupLocalFixity
159 data RnMode = SourceMode -- Renaming source code
160 | InterfaceMode -- Renaming interface declarations.
163 %===================================================
164 \subsubsection{ ENVIRONMENTS}
165 %===================================================
168 --------------------------------
169 type LocalRdrEnv = RdrNameEnv Name
170 type LocalFixityEnv = NameEnv RenamedFixitySig
171 -- We keep the whole fixity sig so that we
172 -- can report line-number info when there is a duplicate
173 -- fixity declaration
175 lookupLocalFixity :: LocalFixityEnv -> Name -> Fixity
176 lookupLocalFixity env name
177 = case lookupNameEnv env name of
178 Just (FixitySig _ fix _) -> fix
179 Nothing -> defaultFixity
183 type ExportAvails = (FiniteMap ModuleName Avails,
184 -- Used to figure out "module M" export specifiers
185 -- Includes avails only from *unqualified* imports
186 -- (see 1.4 Report Section 5.1.1)
188 AvailEnv) -- Used to figure out all other export specifiers.
191 %===================================================
192 \subsubsection{ INTERFACE FILE STUFF}
193 %===================================================
196 type ExportItem = (ModuleName, [RdrAvailInfo])
197 type IfaceDeprecs = Maybe (Either DeprecTxt [(RdrName,DeprecTxt)])
198 -- Nothing => NoDeprecs
199 -- Just (Left t) => DeprecAll
200 -- Just (Right p) => DeprecSome
204 pi_mod :: Module, -- Complete with package info
205 pi_vers :: Version, -- Module version number
206 pi_orphan :: WhetherHasOrphans, -- Whether this module has orphans
207 pi_usages :: [ImportVersion OccName], -- Usages
208 pi_exports :: (Version, [ExportItem]), -- Exports
209 pi_decls :: [(Version, RdrNameHsDecl)], -- Local definitions
210 pi_fixity :: [RdrNameFixitySig], -- Local fixity declarations,
211 pi_insts :: [RdrNameInstDecl], -- Local instance declarations
212 pi_rules :: (Version, [RdrNameRuleDecl]), -- Rules, with their version
213 pi_deprecs :: IfaceDeprecs -- Deprecations
217 %************************************************************************
219 \subsection{The renamer state}
221 %************************************************************************
224 data Ifaces = Ifaces {
226 iPIT :: PackageIfaceTable,
227 -- The ModuleIFaces for modules in other packages
228 -- whose interfaces we have opened
229 -- The declarations in these interface files are held in
230 -- iDecls, iInsts, iRules (below), not in the mi_decls fields
231 -- of the iPIT. What _is_ in the iPIT is:
237 -- The iPIT field is initialised from the compiler's persistent
238 -- package symbol table, and the renamer incrementally adds
242 -- A single, global map of Names to unslurped decls
244 iInsts :: IfaceInsts,
245 -- The as-yet un-slurped instance decls; this bag is depleted when we
246 -- slurp an instance decl so that we don't slurp the same one twice.
247 -- Each is 'gated' by the names that must be available before
248 -- this instance decl is needed.
250 iRules :: IfaceRules,
251 -- Similar to instance decls, only for rules
254 -- These fields persist during the compilation of a single module only
255 iImpModInfo :: ImportedModuleInfo,
256 -- Modules this one depends on: that is, the union
257 -- of the modules its *direct* imports depend on.
258 -- NB: The direct imports have .hi files that enumerate *all* the
259 -- dependencies (direct or not) of the imported module.
262 -- All the names (whether "big" or "small", whether wired-in or not,
263 -- whether locally defined or not) that have been slurped in so far.
266 -- All the (a) non-wired-in (b) "big" (c) non-locally-defined
267 -- names that have been slurped in so far, with their versions.
268 -- This is used to generate the "usage" information for this module.
269 -- Subset of the previous field.
270 -- It's worth keeping separately, because there's no very easy
271 -- way to distinguish the "big" names from the "non-big" ones.
272 -- But this is a decision we might want to revisit.
275 type ImportedModuleInfo = FiniteMap ModuleName
276 (WhetherHasOrphans, IsBootInterface, IsLoaded)
281 %************************************************************************
283 \subsection{Main monad code}
285 %************************************************************************
292 -> PersistentCompilerState
296 -> IO (t, (Bag WarnMsg, Bag ErrMsg), PersistentCompilerState)
298 initRn dflags finder hit hst pcs mod loc do_rn
300 let prs = pcs_PRS pcs
301 let pst = pcs_PST pcs
302 let uniqs = prsNS prs
304 names_var <- newIORef (uniqs, origNames (prsOrig prs),
305 origIParam (prsOrig prs))
306 errs_var <- newIORef (emptyBag,emptyBag)
307 iface_var <- newIORef (initIfaces pcs)
308 let rn_down = RnDown { rn_mod = mod,
314 rn_done = is_done hst pst,
318 rn_ifaces = iface_var,
322 res <- do_rn rn_down ()
324 -- Grab state and record it
325 (warns, errs) <- readIORef errs_var
326 new_ifaces <- readIORef iface_var
327 (new_NS, new_origN, new_origIP) <- readIORef names_var
328 let new_orig = Orig { origNames = new_origN, origIParam = new_origIP }
329 let new_prs = prs { prsOrig = new_orig,
330 prsDecls = iDecls new_ifaces,
331 prsInsts = iInsts new_ifaces,
332 prsRules = iRules new_ifaces,
334 let new_pcs = pcs { pcs_PIT = iPIT new_ifaces,
337 return (res, (warns, errs), new_pcs)
339 is_done :: HomeSymbolTable -> PackageSymbolTable -> Name -> Bool
340 -- Returns True iff the name is in either symbol table
341 is_done hst pst n = maybeToBool (lookupTypeEnv pst n `seqMaybe` lookupTypeEnv hst n)
343 lookupIface :: HomeIfaceTable -> PackageIfaceTable -> ModuleName -> ModIface
344 lookupIface hit pit mod = lookupModuleEnvByName hit mod `orElse`
345 lookupModuleEnvByName pit mod `orElse`
346 pprPanic "lookupIface" (ppr mod)
348 initIfaces :: PersistentCompilerState -> Ifaces
349 initIfaces (PCS { pcs_PIT = pit, pcs_PRS = prs })
350 = Ifaces { iPIT = pit,
351 iDecls = prsDecls prs,
352 iInsts = prsInsts prs,
353 iRules = prsRules prs,
355 iImpModInfo = emptyFM,
356 iSlurp = unitNameSet (mkUnboundName dummyRdrVarName),
357 -- Pretend that the dummy unbound name has already been
358 -- slurped. This is what's returned for an out-of-scope name,
359 -- and we don't want thereby to try to suck it in!
364 initRnMS :: GlobalRdrEnv -> LocalFixityEnv -> RnMode -> RnMS r -> RnM d r
365 initRnMS rn_env fixity_env mode thing_inside rn_down g_down
367 s_down = SDown { rn_genv = rn_env, rn_lenv = emptyRdrEnv,
368 rn_fixenv = fixity_env, rn_mode = mode }
370 thing_inside rn_down s_down
372 initIfaceRnMS :: Module -> RnMS r -> RnM d r
373 initIfaceRnMS mod thing_inside
374 = initRnMS emptyRdrEnv emptyNameEnv InterfaceMode $
375 setModuleRn mod thing_inside
379 @renameSourceCode@ is used to rename stuff ``out-of-line'';
380 that is, not as part of the main renamer.
381 Sole examples: derived definitions,
382 which are only generated in the type checker.
384 The @NameSupply@ includes a @UniqueSupply@, so if you call it more than
385 once you must either split it, or install a fresh unique supply.
388 renameSourceCode :: DynFlags
390 -> PersistentRenamerState
394 renameSourceCode dflags mod prs m
396 -- It's not really unsafe! When renaming source code we
397 -- only do any I/O if we need to read in a fixity declaration;
398 -- and that doesn't happen in pragmas etc
400 mkSplitUniqSupply 'r' >>= \ new_us ->
401 newIORef (new_us, origNames (prsOrig prs),
402 origIParam (prsOrig prs)) >>= \ names_var ->
403 newIORef (emptyBag,emptyBag) >>= \ errs_var ->
405 rn_down = RnDown { rn_dflags = dflags,
406 rn_loc = generatedSrcLoc, rn_ns = names_var,
409 rn_done = bogus "rn_done", rn_hit = bogus "rn_hit",
410 rn_ifaces = bogus "rn_ifaces", rn_finder = bogus "rn_finder"
412 s_down = SDown { rn_mode = InterfaceMode,
413 -- So that we can refer to PrelBase.True etc
414 rn_genv = emptyRdrEnv, rn_lenv = emptyRdrEnv,
415 rn_fixenv = emptyNameEnv }
417 m rn_down s_down >>= \ result ->
419 readIORef errs_var >>= \ (warns,errs) ->
421 (if not (isEmptyBag errs) then
422 pprTrace "Urk! renameSourceCode found errors" (display errs)
424 else if not (isEmptyBag warns) then
425 pprTrace "Note: renameSourceCode found warnings" (display warns)
433 display errs = pprBagOfErrors errs
435 bogus s = panic ("rnameSourceCode: " ++ s) -- Used for unused record fields
437 {-# INLINE thenRn #-}
438 {-# INLINE thenRn_ #-}
439 {-# INLINE returnRn #-}
442 returnRn :: a -> RnM d a
443 thenRn :: RnM d a -> (a -> RnM d b) -> RnM d b
444 thenRn_ :: RnM d a -> RnM d b -> RnM d b
445 andRn :: (a -> a -> a) -> RnM d a -> RnM d a -> RnM d a
446 mapRn :: (a -> RnM d b) -> [a] -> RnM d [b]
447 mapRn_ :: (a -> RnM d b) -> [a] -> RnM d ()
448 mapMaybeRn :: (a -> RnM d (Maybe b)) -> [a] -> RnM d [b]
449 flatMapRn :: (a -> RnM d [b]) -> [a] -> RnM d [b]
450 sequenceRn :: [RnM d a] -> RnM d [a]
451 foldlRn :: (b -> a -> RnM d b) -> b -> [a] -> RnM d b
452 mapAndUnzipRn :: (a -> RnM d (b,c)) -> [a] -> RnM d ([b],[c])
453 fixRn :: (a -> RnM d a) -> RnM d a
455 returnRn v gdown ldown = return v
456 thenRn m k gdown ldown = m gdown ldown >>= \ r -> k r gdown ldown
457 thenRn_ m k gdown ldown = m gdown ldown >> k gdown ldown
458 fixRn m gdown ldown = fixIO (\r -> m r gdown ldown)
459 andRn combiner m1 m2 gdown ldown
460 = m1 gdown ldown >>= \ res1 ->
461 m2 gdown ldown >>= \ res2 ->
462 return (combiner res1 res2)
464 sequenceRn [] = returnRn []
465 sequenceRn (m:ms) = m `thenRn` \ r ->
466 sequenceRn ms `thenRn` \ rs ->
469 mapRn f [] = returnRn []
471 = f x `thenRn` \ r ->
472 mapRn f xs `thenRn` \ rs ->
475 mapRn_ f [] = returnRn ()
480 foldlRn k z [] = returnRn z
481 foldlRn k z (x:xs) = k z x `thenRn` \ z' ->
484 mapAndUnzipRn f [] = returnRn ([],[])
485 mapAndUnzipRn f (x:xs)
486 = f x `thenRn` \ (r1, r2) ->
487 mapAndUnzipRn f xs `thenRn` \ (rs1, rs2) ->
488 returnRn (r1:rs1, r2:rs2)
490 mapAndUnzip3Rn f [] = returnRn ([],[],[])
491 mapAndUnzip3Rn f (x:xs)
492 = f x `thenRn` \ (r1, r2, r3) ->
493 mapAndUnzip3Rn f xs `thenRn` \ (rs1, rs2, rs3) ->
494 returnRn (r1:rs1, r2:rs2, r3:rs3)
496 mapMaybeRn f [] = returnRn []
497 mapMaybeRn f (x:xs) = f x `thenRn` \ maybe_r ->
498 mapMaybeRn f xs `thenRn` \ rs ->
500 Nothing -> returnRn rs
501 Just r -> returnRn (r:rs)
503 flatMapRn f [] = returnRn []
504 flatMapRn f (x:xs) = f x `thenRn` \ r ->
505 flatMapRn f xs `thenRn` \ rs ->
511 %************************************************************************
513 \subsection{Boring plumbing for common part}
515 %************************************************************************
519 \subsubsection{ Errors and warnings}
520 %=====================
523 failWithRn :: a -> Message -> RnM d a
524 failWithRn res msg (RnDown {rn_errs = errs_var, rn_loc = loc}) l_down
525 = readIORef errs_var >>= \ (warns,errs) ->
526 writeIORef errs_var (warns, errs `snocBag` err) >>
529 err = addShortErrLocLine loc msg
531 warnWithRn :: a -> Message -> RnM d a
532 warnWithRn res msg (RnDown {rn_errs = errs_var, rn_loc = loc}) l_down
533 = readIORef errs_var >>= \ (warns,errs) ->
534 writeIORef errs_var (warns `snocBag` warn, errs) >>
537 warn = addShortWarnLocLine loc msg
539 addErrRn :: Message -> RnM d ()
540 addErrRn err = failWithRn () err
542 checkRn :: Bool -> Message -> RnM d () -- Check that a condition is true
543 checkRn False err = addErrRn err
544 checkRn True err = returnRn ()
546 warnCheckRn :: Bool -> Message -> RnM d () -- Check that a condition is true
547 warnCheckRn False err = addWarnRn err
548 warnCheckRn True err = returnRn ()
550 addWarnRn :: Message -> RnM d ()
551 addWarnRn warn = warnWithRn () warn
553 checkErrsRn :: RnM d Bool -- True <=> no errors so far
554 checkErrsRn (RnDown {rn_errs = errs_var}) l_down
555 = readIORef errs_var >>= \ (warns,errs) ->
556 return (isEmptyBag errs)
558 doptRn :: DynFlag -> RnM d Bool
559 doptRn dflag (RnDown { rn_dflags = dflags}) l_down
560 = return (dopt dflag dflags)
562 getDOptsRn :: RnM d DynFlags
563 getDOptsRn (RnDown { rn_dflags = dflags}) l_down
569 \subsubsection{Source location}
570 %=====================
573 pushSrcLocRn :: SrcLoc -> RnM d a -> RnM d a
574 pushSrcLocRn loc' m down l_down
575 = m (down {rn_loc = loc'}) l_down
577 getSrcLocRn :: RnM d SrcLoc
578 getSrcLocRn down l_down
579 = return (rn_loc down)
583 \subsubsection{The finder and home symbol table}
584 %=====================
587 getFinderRn :: RnM d Finder
588 getFinderRn down l_down = return (rn_finder down)
590 getHomeIfaceTableRn :: RnM d HomeIfaceTable
591 getHomeIfaceTableRn down l_down = return (rn_hit down)
593 checkAlreadyAvailable :: Name -> RnM d Bool
594 checkAlreadyAvailable name down l_down = return (rn_done down name)
598 \subsubsection{Name supply}
599 %=====================
602 getNameSupplyRn :: RnM d (UniqSupply, OrigNameNameEnv, OrigNameIParamEnv)
603 getNameSupplyRn rn_down l_down
604 = readIORef (rn_ns rn_down)
606 setNameSupplyRn :: (UniqSupply, OrigNameNameEnv, OrigNameIParamEnv) -> RnM d ()
607 setNameSupplyRn names' (RnDown {rn_ns = names_var}) l_down
608 = writeIORef names_var names'
610 getUniqRn :: RnM d Unique
611 getUniqRn (RnDown {rn_ns = names_var}) l_down
612 = readIORef names_var >>= \ (us, cache, ipcache) ->
614 (us1,us') = splitUniqSupply us
616 writeIORef names_var (us', cache, ipcache) >>
617 return (uniqFromSupply us1)
621 \subsubsection{ Module}
622 %=====================
625 getModuleRn :: RnM d Module
626 getModuleRn (RnDown {rn_mod = mod}) l_down
629 setModuleRn :: Module -> RnM d a -> RnM d a
630 setModuleRn new_mod enclosed_thing rn_down l_down
631 = enclosed_thing (rn_down {rn_mod = new_mod}) l_down
635 %************************************************************************
637 \subsection{Plumbing for rename-source part}
639 %************************************************************************
642 \subsubsection{ RnEnv}
643 %=====================
646 getLocalNameEnv :: RnMS LocalRdrEnv
647 getLocalNameEnv rn_down (SDown {rn_lenv = local_env})
650 getGlobalNameEnv :: RnMS GlobalRdrEnv
651 getGlobalNameEnv rn_down (SDown {rn_genv = global_env})
654 setLocalNameEnv :: LocalRdrEnv -> RnMS a -> RnMS a
655 setLocalNameEnv local_env' m rn_down l_down
656 = m rn_down (l_down {rn_lenv = local_env'})
658 getFixityEnv :: RnMS LocalFixityEnv
659 getFixityEnv rn_down (SDown {rn_fixenv = fixity_env})
662 extendFixityEnv :: [(Name, RenamedFixitySig)] -> RnMS a -> RnMS a
663 extendFixityEnv fixes enclosed_scope
664 rn_down l_down@(SDown {rn_fixenv = fixity_env})
666 new_fixity_env = extendNameEnvList fixity_env fixes
668 enclosed_scope rn_down (l_down {rn_fixenv = new_fixity_env})
672 \subsubsection{ Mode}
673 %=====================
676 getModeRn :: RnMS RnMode
677 getModeRn rn_down (SDown {rn_mode = mode})
680 setModeRn :: RnMode -> RnMS a -> RnMS a
681 setModeRn new_mode thing_inside rn_down l_down
682 = thing_inside rn_down (l_down {rn_mode = new_mode})
686 %************************************************************************
688 \subsection{Plumbing for rename-globals part}
690 %************************************************************************
693 getIfacesRn :: RnM d Ifaces
694 getIfacesRn (RnDown {rn_ifaces = iface_var}) _
695 = readIORef iface_var
697 setIfacesRn :: Ifaces -> RnM d ()
698 setIfacesRn ifaces (RnDown {rn_ifaces = iface_var}) _
699 = writeIORef iface_var ifaces