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 )
34 import IO ( hPutStr, stderr )
38 import RnHsSyn ( RenamedFixitySig )
39 import HscTypes ( AvailEnv, lookupType,
41 ImportedModuleInfo, WhetherHasOrphans, ImportVersion,
42 PersistentRenamerState(..), Avails,
43 DeclsMap, IfaceInsts, IfaceRules,
44 HomeSymbolTable, TyThing,
45 PersistentCompilerState(..), GlobalRdrEnv,
46 HomeIfaceTable, PackageIfaceTable,
48 import BasicTypes ( Version, defaultFixity )
49 import ErrUtils ( addShortErrLocLine, addShortWarnLocLine,
50 Message, Messages, errorsFound, warningsFound,
51 printErrorsAndWarnings
53 import RdrName ( RdrName, dummyRdrVarName, rdrNameModule, rdrNameOcc,
54 RdrNameEnv, emptyRdrEnv, extendRdrEnv,
55 addListToRdrEnv, rdrEnvToList, rdrEnvElts
57 import Name ( Name, OccName, NamedThing(..),
59 decode, mkLocalName, mkKnownKeyGlobal
61 import Name ( NameEnv, lookupNameEnv, emptyNameEnv, unitNameEnv, extendNameEnvList )
62 import Module ( Module, ModuleName, ModuleSet, emptyModuleSet )
64 import CmdLineOpts ( DynFlags, DynFlag(..), dopt )
65 import SrcLoc ( SrcLoc, generatedSrcLoc, noSrcLoc )
66 import Unique ( Unique )
67 import FiniteMap ( FiniteMap )
68 import Bag ( Bag, emptyBag, isEmptyBag, snocBag )
71 import PrelNames ( mkUnboundName )
73 infixr 9 `thenRn`, `thenRn_`
77 %************************************************************************
79 \subsection{Somewhat magical interface to other monads}
81 %************************************************************************
84 ioToRnM :: IO r -> RnM d (Either IOError r)
85 ioToRnM io rn_down g_down = (io >>= \ ok -> return (Right ok))
87 (\ err -> return (Left err))
89 ioToRnM_no_fail :: IO r -> RnM d r
90 ioToRnM_no_fail io rn_down g_down
91 = (io >>= \ ok -> return ok)
93 (\ err -> panic "ioToRnM_no_fail: the I/O operation failed!")
95 traceRn :: SDoc -> RnM d ()
97 = doptRn Opt_D_dump_rn_trace `thenRn` \b ->
98 if b then putDocRn msg else returnRn ()
100 traceHiDiffsRn :: SDoc -> RnM d ()
102 = doptRn Opt_D_dump_hi_diffs `thenRn` \b ->
103 if b then putDocRn msg else returnRn ()
105 putDocRn :: SDoc -> RnM d ()
106 putDocRn msg = ioToRnM (printErrs alwaysQualify msg) `thenRn_`
111 %************************************************************************
113 \subsection{Data types}
115 %************************************************************************
117 %===================================================
118 \subsubsection{ MONAD TYPES}
119 %===================================================
122 type RnM d r = RnDown -> d -> IO r
123 type RnMS r = RnM SDown r -- Renaming source
124 type RnMG r = RnM () r -- Getting global names etc
129 rn_mod :: Module, -- This module
130 rn_loc :: SrcLoc, -- Current locn
132 rn_dflags :: DynFlags,
134 rn_hit :: HomeIfaceTable,
135 rn_done :: Name -> Maybe TyThing, -- Tells what things (both in the
136 -- home package and other packages)
137 -- were already available (i.e. in
138 -- the relevant SymbolTable) before
139 -- compiling this module
140 -- The Name passed to rn_done is guaranteed to be a Global,
141 -- so it has a Module, so it can be looked up
143 rn_errs :: IORef Messages,
144 rn_ns :: IORef NameSupply,
145 rn_ifaces :: IORef Ifaces
148 -- For renaming source code
152 rn_genv :: GlobalRdrEnv, -- Top level environment
154 rn_lenv :: LocalRdrEnv, -- Local name envt
155 -- Does *not* include global name envt; may shadow it
156 -- Includes both ordinary variables and type variables;
157 -- they are kept distinct because tyvar have a different
158 -- occurrence contructor (Name.TvOcc)
159 -- We still need the unsullied global name env so that
160 -- we can look up record field names
162 rn_fixenv :: LocalFixityEnv -- Local fixities (for non-top-level
164 -- The global fixities are held in the
165 -- HIT or PIT. Why? See the comments
166 -- with RnIfaces.lookupLocalFixity
169 data RnMode = SourceMode -- Renaming source code
170 | InterfaceMode -- Renaming interface declarations.
171 | CmdLineMode -- Renaming a command-line expression
173 isInterfaceMode InterfaceMode = True
174 isInterfaceMode _ = False
177 %===================================================
178 \subsubsection{ ENVIRONMENTS}
179 %===================================================
182 --------------------------------
183 type LocalRdrEnv = RdrNameEnv Name
184 type LocalFixityEnv = NameEnv RenamedFixitySig
185 -- We keep the whole fixity sig so that we
186 -- can report line-number info when there is a duplicate
187 -- fixity declaration
189 emptyLocalFixityEnv :: LocalFixityEnv
190 emptyLocalFixityEnv = emptyNameEnv
192 lookupLocalFixity :: LocalFixityEnv -> Name -> Fixity
193 lookupLocalFixity env name
194 = case lookupNameEnv env name of
195 Just (FixitySig _ fix _) -> fix
196 Nothing -> defaultFixity
200 type ExportAvails = (FiniteMap ModuleName Avails,
201 -- Used to figure out "module M" export specifiers
202 -- Includes avails only from *unqualified* imports
203 -- (see 1.4 Report Section 5.1.1)
205 AvailEnv) -- Used to figure out all other export specifiers.
208 %===================================================
209 \subsubsection{ INTERFACE FILE STUFF}
210 %===================================================
213 type ExportItem = (ModuleName, [RdrAvailInfo])
214 type IfaceDeprecs = Maybe (Either DeprecTxt [(RdrName,DeprecTxt)])
215 -- Nothing => NoDeprecs
216 -- Just (Left t) => DeprecAll
217 -- Just (Right p) => DeprecSome
221 pi_mod :: Module, -- Complete with package info
222 pi_vers :: Version, -- Module version number
223 pi_orphan :: WhetherHasOrphans, -- Whether this module has orphans
224 pi_usages :: [ImportVersion OccName], -- Usages
225 pi_exports :: (Version, [ExportItem]), -- Exports
226 pi_decls :: [(Version, RdrNameTyClDecl)], -- Local definitions
227 pi_fixity :: [RdrNameFixitySig], -- Local fixity declarations,
228 pi_insts :: [RdrNameInstDecl], -- Local instance declarations
229 pi_rules :: (Version, [RdrNameRuleDecl]), -- Rules, with their version
230 pi_deprecs :: IfaceDeprecs -- Deprecations
234 %************************************************************************
236 \subsection{The renamer state}
238 %************************************************************************
241 data Ifaces = Ifaces {
243 iPIT :: PackageIfaceTable,
244 -- The ModuleIFaces for modules in other packages
245 -- whose interfaces we have opened
246 -- The declarations in these interface files are held in
247 -- iDecls, iInsts, iRules (below), not in the mi_decls fields
248 -- of the iPIT. What _is_ in the iPIT is:
254 -- The iPIT field is initialised from the compiler's persistent
255 -- package symbol table, and the renamer incrementally adds
258 iImpModInfo :: ImportedModuleInfo,
259 -- Modules that we know something about, because they are mentioned
260 -- in interface files, BUT which we have not loaded yet.
261 -- No module is both in here and in the PIT
264 -- A single, global map of Names to unslurped decls
266 iInsts :: IfaceInsts,
267 -- The as-yet un-slurped instance decls; this bag is depleted when we
268 -- slurp an instance decl so that we don't slurp the same one twice.
269 -- Each is 'gated' by the names that must be available before
270 -- this instance decl is needed.
272 iRules :: IfaceRules,
273 -- Similar to instance decls, only for rules
276 -- These fields persist during the compilation of a single module only
278 -- All the names (whether "big" or "small", whether wired-in or not,
279 -- whether locally defined or not) that have been slurped in so far.
281 iVSlurp :: (ModuleSet, NameSet)
282 -- The Names are all the (a) non-wired-in
284 -- (c) non-locally-defined
286 -- names that have been slurped in so far, with their versions.
287 -- This is used to generate the "usage" information for this module.
288 -- Subset of the previous field.
290 -- The module set is the non-home-package modules from which we have
291 -- slurped at least one name.
292 -- It's worth keeping separately, because there's no very easy
293 -- way to distinguish the "big" names from the "non-big" ones.
294 -- But this is a decision we might want to revisit.
299 %************************************************************************
301 \subsection{Main monad code}
303 %************************************************************************
306 runRn dflags hit hst pcs mod do_rn
307 = do { (pcs, msgs, r) <- initRn dflags hit hst pcs mod do_rn ;
308 printErrorsAndWarnings alwaysQualify msgs ;
309 return (pcs, errorsFound msgs, r)
313 -> HomeIfaceTable -> HomeSymbolTable
314 -> PersistentCompilerState
317 -> IO (PersistentCompilerState, Messages, t)
319 initRn dflags hit hst pcs mod do_rn
321 let prs = pcs_PRS pcs
322 let pte = pcs_PTE pcs
323 let ifaces = Ifaces { iPIT = pcs_PIT pcs,
324 iDecls = prsDecls prs,
325 iInsts = prsInsts prs,
326 iRules = prsRules prs,
328 iImpModInfo = prsImpMods prs,
329 iSlurp = unitNameSet (mkUnboundName dummyRdrVarName),
330 -- Pretend that the dummy unbound name has already been
331 -- slurped. This is what's returned for an out-of-scope name,
332 -- and we don't want thereby to try to suck it in!
333 iVSlurp = (emptyModuleSet, emptyNameSet)
335 names_var <- newIORef (prsOrig prs)
336 errs_var <- newIORef (emptyBag,emptyBag)
337 iface_var <- newIORef ifaces
338 let rn_down = RnDown { rn_mod = mod,
343 rn_done = lookupType hst pte,
347 rn_ifaces = iface_var,
351 res <- do_rn rn_down ()
353 -- Grab state and record it
354 (warns, errs) <- readIORef errs_var
355 new_ifaces <- readIORef iface_var
356 new_orig <- readIORef names_var
357 let new_prs = prs { prsOrig = new_orig,
358 prsImpMods = iImpModInfo new_ifaces,
359 prsDecls = iDecls new_ifaces,
360 prsInsts = iInsts new_ifaces,
361 prsRules = iRules new_ifaces }
362 let new_pcs = pcs { pcs_PIT = iPIT new_ifaces,
365 return (new_pcs, (warns, errs), res)
367 initRnMS :: GlobalRdrEnv -> LocalFixityEnv -> RnMode
370 initRnMS rn_env fixity_env mode thing_inside rn_down g_down
371 -- The fixity_env appears in both the rn_fixenv field
372 -- and in the HIT. See comments with RnHiFiles.lookupFixityRn
374 s_down = SDown { rn_genv = rn_env, rn_lenv = emptyRdrEnv,
375 rn_fixenv = fixity_env, rn_mode = mode }
377 thing_inside rn_down s_down
379 initIfaceRnMS :: Module -> RnMS r -> RnM d r
380 initIfaceRnMS mod thing_inside
381 = initRnMS emptyRdrEnv emptyLocalFixityEnv InterfaceMode $
382 setModuleRn mod thing_inside
385 @renameDerivedCode@ is used to rename stuff ``out-of-line'';
386 that is, not as part of the main renamer.
387 Sole examples: derived definitions,
388 which are only generated in the type checker.
390 The @NameSupply@ includes a @UniqueSupply@, so if you call it more than
391 once you must either split it, or install a fresh unique supply.
394 renameDerivedCode :: DynFlags
396 -> PersistentRenamerState
400 renameDerivedCode dflags mod prs thing_inside
402 -- It's not really unsafe! When renaming source code we
403 -- only do any I/O if we need to read in a fixity declaration;
404 -- and that doesn't happen in pragmas etc
406 do { us <- mkSplitUniqSupply 'r'
407 ; names_var <- newIORef ((prsOrig prs) { nsUniqs = us })
408 ; errs_var <- newIORef (emptyBag,emptyBag)
410 ; let rn_down = RnDown { rn_dflags = dflags,
411 rn_loc = generatedSrcLoc, rn_ns = names_var,
414 rn_done = bogus "rn_done",
415 rn_hit = bogus "rn_hit",
416 rn_ifaces = bogus "rn_ifaces"
418 ; let s_down = SDown { rn_mode = InterfaceMode,
419 -- So that we can refer to PrelBase.True etc
420 rn_genv = emptyRdrEnv, rn_lenv = emptyRdrEnv,
421 rn_fixenv = emptyLocalFixityEnv }
423 ; result <- thing_inside rn_down s_down
424 ; messages <- readIORef errs_var
426 ; if bad messages then
427 do { hPutStr stderr "Urk! renameDerivedCode found errors or warnings"
428 ; printErrorsAndWarnings alwaysQualify messages
437 bad messages = errorsFound messages || warningsFound messages
439 bad messages = errorsFound messages
442 bogus s = panic ("rnameSourceCode: " ++ s) -- Used for unused record fields
444 {-# INLINE thenRn #-}
445 {-# INLINE thenRn_ #-}
446 {-# INLINE returnRn #-}
449 returnRn :: a -> RnM d a
450 thenRn :: RnM d a -> (a -> RnM d b) -> RnM d b
451 thenRn_ :: RnM d a -> RnM d b -> RnM d b
452 andRn :: (a -> a -> a) -> RnM d a -> RnM d a -> RnM d a
453 mapRn :: (a -> RnM d b) -> [a] -> RnM d [b]
454 mapRn_ :: (a -> RnM d b) -> [a] -> RnM d ()
455 mapMaybeRn :: (a -> RnM d (Maybe b)) -> [a] -> RnM d [b]
456 flatMapRn :: (a -> RnM d [b]) -> [a] -> RnM d [b]
457 sequenceRn :: [RnM d a] -> RnM d [a]
458 sequenceRn_ :: [RnM d a] -> RnM d ()
459 foldlRn :: (b -> a -> RnM d b) -> b -> [a] -> RnM d b
460 mapAndUnzipRn :: (a -> RnM d (b,c)) -> [a] -> RnM d ([b],[c])
461 fixRn :: (a -> RnM d a) -> RnM d a
463 returnRn v gdown ldown = return v
464 thenRn m k gdown ldown = m gdown ldown >>= \ r -> k r gdown ldown
465 thenRn_ m k gdown ldown = m gdown ldown >> k gdown ldown
466 fixRn m gdown ldown = fixIO (\r -> m r gdown ldown)
467 andRn combiner m1 m2 gdown ldown
468 = m1 gdown ldown >>= \ res1 ->
469 m2 gdown ldown >>= \ res2 ->
470 return (combiner res1 res2)
472 sequenceRn [] = returnRn []
473 sequenceRn (m:ms) = m `thenRn` \ r ->
474 sequenceRn ms `thenRn` \ rs ->
477 sequenceRn_ [] = returnRn ()
478 sequenceRn_ (m:ms) = m `thenRn_` sequenceRn_ ms
480 mapRn f [] = returnRn []
482 = f x `thenRn` \ r ->
483 mapRn f xs `thenRn` \ rs ->
486 mapRn_ f [] = returnRn ()
491 foldlRn k z [] = returnRn z
492 foldlRn k z (x:xs) = k z x `thenRn` \ z' ->
495 mapAndUnzipRn f [] = returnRn ([],[])
496 mapAndUnzipRn f (x:xs)
497 = f x `thenRn` \ (r1, r2) ->
498 mapAndUnzipRn f xs `thenRn` \ (rs1, rs2) ->
499 returnRn (r1:rs1, r2:rs2)
501 mapAndUnzip3Rn f [] = returnRn ([],[],[])
502 mapAndUnzip3Rn f (x:xs)
503 = f x `thenRn` \ (r1, r2, r3) ->
504 mapAndUnzip3Rn f xs `thenRn` \ (rs1, rs2, rs3) ->
505 returnRn (r1:rs1, r2:rs2, r3:rs3)
507 mapMaybeRn f [] = returnRn []
508 mapMaybeRn f (x:xs) = f x `thenRn` \ maybe_r ->
509 mapMaybeRn f xs `thenRn` \ rs ->
511 Nothing -> returnRn rs
512 Just r -> returnRn (r:rs)
514 flatMapRn f [] = returnRn []
515 flatMapRn f (x:xs) = f x `thenRn` \ r ->
516 flatMapRn f xs `thenRn` \ rs ->
522 %************************************************************************
524 \subsection{Boring plumbing for common part}
526 %************************************************************************
530 \subsubsection{ Errors and warnings}
531 %=====================
534 failWithRn :: a -> Message -> RnM d a
535 failWithRn res msg (RnDown {rn_errs = errs_var, rn_loc = loc}) l_down
536 = readIORef errs_var >>= \ (warns,errs) ->
537 writeIORef errs_var (warns, errs `snocBag` err) >>
540 err = addShortErrLocLine loc msg
542 warnWithRn :: a -> Message -> RnM d a
543 warnWithRn res msg (RnDown {rn_errs = errs_var, rn_loc = loc}) l_down
544 = readIORef errs_var >>= \ (warns,errs) ->
545 writeIORef errs_var (warns `snocBag` warn, errs) >>
548 warn = addShortWarnLocLine loc msg
550 addErrRn :: Message -> RnM d ()
551 addErrRn err = failWithRn () err
553 checkRn :: Bool -> Message -> RnM d () -- Check that a condition is true
554 checkRn False err = addErrRn err
555 checkRn True err = returnRn ()
557 warnCheckRn :: Bool -> Message -> RnM d () -- Check that a condition is true
558 warnCheckRn False err = addWarnRn err
559 warnCheckRn True err = returnRn ()
561 addWarnRn :: Message -> RnM d ()
562 addWarnRn warn = warnWithRn () warn
564 checkErrsRn :: RnM d Bool -- True <=> no errors so far
565 checkErrsRn (RnDown {rn_errs = errs_var}) l_down
566 = readIORef errs_var >>= \ (warns,errs) ->
567 return (isEmptyBag errs)
569 doptRn :: DynFlag -> RnM d Bool
570 doptRn dflag (RnDown { rn_dflags = dflags}) l_down
571 = return (dopt dflag dflags)
573 getDOptsRn :: RnM d DynFlags
574 getDOptsRn (RnDown { rn_dflags = dflags}) l_down
580 \subsubsection{Source location}
581 %=====================
584 pushSrcLocRn :: SrcLoc -> RnM d a -> RnM d a
585 pushSrcLocRn loc' m down l_down
586 = m (down {rn_loc = loc'}) l_down
588 getSrcLocRn :: RnM d SrcLoc
589 getSrcLocRn down l_down
590 = return (rn_loc down)
594 \subsubsection{The finder and home symbol table}
595 %=====================
598 getHomeIfaceTableRn :: RnM d HomeIfaceTable
599 getHomeIfaceTableRn down l_down = return (rn_hit down)
601 getTypeEnvRn :: RnM d (Name -> Maybe TyThing)
602 getTypeEnvRn down l_down = return (rn_done down)
606 \subsubsection{Name supply}
607 %=====================
610 getNameSupplyRn :: RnM d NameSupply
611 getNameSupplyRn rn_down l_down
612 = readIORef (rn_ns rn_down)
614 setNameSupplyRn :: NameSupply -> RnM d ()
615 setNameSupplyRn names' (RnDown {rn_ns = names_var}) l_down
616 = writeIORef names_var names'
618 getUniqRn :: RnM d Unique
619 getUniqRn (RnDown {rn_ns = names_var}) l_down
620 = readIORef names_var >>= \ ns ->
622 (us1,us') = splitUniqSupply (nsUniqs ns)
624 writeIORef names_var (ns {nsUniqs = us'}) >>
625 return (uniqFromSupply us1)
629 \subsubsection{ Module}
630 %=====================
633 getModuleRn :: RnM d Module
634 getModuleRn (RnDown {rn_mod = mod}) l_down
637 setModuleRn :: Module -> RnM d a -> RnM d a
638 setModuleRn new_mod enclosed_thing rn_down l_down
639 = enclosed_thing (rn_down {rn_mod = new_mod}) l_down
643 %************************************************************************
645 \subsection{Plumbing for rename-source part}
647 %************************************************************************
650 \subsubsection{ RnEnv}
651 %=====================
654 getLocalNameEnv :: RnMS LocalRdrEnv
655 getLocalNameEnv rn_down (SDown {rn_lenv = local_env})
658 getGlobalNameEnv :: RnMS GlobalRdrEnv
659 getGlobalNameEnv rn_down (SDown {rn_genv = global_env})
662 setLocalNameEnv :: LocalRdrEnv -> RnMS a -> RnMS a
663 setLocalNameEnv local_env' m rn_down l_down
664 = m rn_down (l_down {rn_lenv = local_env'})
666 getFixityEnv :: RnMS LocalFixityEnv
667 getFixityEnv rn_down (SDown {rn_fixenv = fixity_env})
670 extendFixityEnv :: [(Name, RenamedFixitySig)] -> RnMS a -> RnMS a
671 extendFixityEnv fixes enclosed_scope
672 rn_down l_down@(SDown {rn_fixenv = fixity_env})
674 new_fixity_env = extendNameEnvList fixity_env fixes
676 enclosed_scope rn_down (l_down {rn_fixenv = new_fixity_env})
680 \subsubsection{ Mode}
681 %=====================
684 getModeRn :: RnMS RnMode
685 getModeRn rn_down (SDown {rn_mode = mode})
688 setModeRn :: RnMode -> RnMS a -> RnMS a
689 setModeRn new_mode thing_inside rn_down l_down
690 = thing_inside rn_down (l_down {rn_mode = new_mode})
694 %************************************************************************
696 \subsection{Plumbing for rename-globals part}
698 %************************************************************************
701 getIfacesRn :: RnM d Ifaces
702 getIfacesRn (RnDown {rn_ifaces = iface_var}) _
703 = readIORef iface_var
705 setIfacesRn :: Ifaces -> RnM d ()
706 setIfacesRn ifaces (RnDown {rn_ifaces = iface_var}) _
707 = writeIORef iface_var ifaces