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
303 uniqs <- mkSplitUniqSupply 'r'
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_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 }
333 let new_pcs = pcs { pcs_PIT = iPIT new_ifaces,
336 return (res, (warns, errs), new_pcs)
338 is_done :: HomeSymbolTable -> PackageSymbolTable -> Name -> Bool
339 -- Returns True iff the name is in either symbol table
340 is_done hst pst n = maybeToBool (lookupTypeEnv pst n `seqMaybe` lookupTypeEnv hst n)
342 lookupIface :: HomeIfaceTable -> PackageIfaceTable -> ModuleName -> ModIface
343 lookupIface hit pit mod = lookupModuleEnvByName hit mod `orElse`
344 lookupModuleEnvByName pit mod `orElse`
345 pprPanic "lookupIface" (ppr mod)
347 initIfaces :: PersistentCompilerState -> Ifaces
348 initIfaces (PCS { pcs_PIT = pit, pcs_PRS = prs })
349 = Ifaces { iPIT = pit,
350 iDecls = prsDecls prs,
351 iInsts = prsInsts prs,
352 iRules = prsRules prs,
354 iImpModInfo = emptyFM,
355 iSlurp = unitNameSet (mkUnboundName dummyRdrVarName),
356 -- Pretend that the dummy unbound name has already been
357 -- slurped. This is what's returned for an out-of-scope name,
358 -- and we don't want thereby to try to suck it in!
363 initRnMS :: GlobalRdrEnv -> LocalFixityEnv -> RnMode -> RnMS r -> RnM d r
364 initRnMS rn_env fixity_env mode thing_inside rn_down g_down
366 s_down = SDown { rn_genv = rn_env, rn_lenv = emptyRdrEnv,
367 rn_fixenv = fixity_env, rn_mode = mode }
369 thing_inside rn_down s_down
371 initIfaceRnMS :: Module -> RnMS r -> RnM d r
372 initIfaceRnMS mod thing_inside
373 = initRnMS emptyRdrEnv emptyNameEnv InterfaceMode $
374 setModuleRn mod thing_inside
378 @renameSourceCode@ is used to rename stuff ``out-of-line'';
379 that is, not as part of the main renamer.
380 Sole examples: derived definitions,
381 which are only generated in the type checker.
383 The @NameSupply@ includes a @UniqueSupply@, so if you call it more than
384 once you must either split it, or install a fresh unique supply.
387 renameSourceCode :: DynFlags
389 -> PersistentRenamerState
393 renameSourceCode dflags mod prs m
395 -- It's not really unsafe! When renaming source code we
396 -- only do any I/O if we need to read in a fixity declaration;
397 -- and that doesn't happen in pragmas etc
399 mkSplitUniqSupply 'r' >>= \ new_us ->
400 newIORef (new_us, origNames (prsOrig prs),
401 origIParam (prsOrig prs)) >>= \ names_var ->
402 newIORef (emptyBag,emptyBag) >>= \ errs_var ->
404 rn_down = RnDown { rn_dflags = dflags,
405 rn_loc = generatedSrcLoc, rn_ns = names_var,
408 rn_done = bogus "rn_done", rn_hit = bogus "rn_hit",
409 rn_ifaces = bogus "rn_ifaces", rn_finder = bogus "rn_finder"
411 s_down = SDown { rn_mode = InterfaceMode,
412 -- So that we can refer to PrelBase.True etc
413 rn_genv = emptyRdrEnv, rn_lenv = emptyRdrEnv,
414 rn_fixenv = emptyNameEnv }
416 m rn_down s_down >>= \ result ->
418 readIORef errs_var >>= \ (warns,errs) ->
420 (if not (isEmptyBag errs) then
421 pprTrace "Urk! renameSourceCode found errors" (display errs)
423 else if not (isEmptyBag warns) then
424 pprTrace "Note: renameSourceCode found warnings" (display warns)
432 display errs = pprBagOfErrors errs
434 bogus s = panic ("rnameSourceCode: " ++ s) -- Used for unused record fields
436 {-# INLINE thenRn #-}
437 {-# INLINE thenRn_ #-}
438 {-# INLINE returnRn #-}
441 returnRn :: a -> RnM d a
442 thenRn :: RnM d a -> (a -> RnM d b) -> RnM d b
443 thenRn_ :: RnM d a -> RnM d b -> RnM d b
444 andRn :: (a -> a -> a) -> RnM d a -> RnM d a -> RnM d a
445 mapRn :: (a -> RnM d b) -> [a] -> RnM d [b]
446 mapRn_ :: (a -> RnM d b) -> [a] -> RnM d ()
447 mapMaybeRn :: (a -> RnM d (Maybe b)) -> [a] -> RnM d [b]
448 flatMapRn :: (a -> RnM d [b]) -> [a] -> RnM d [b]
449 sequenceRn :: [RnM d a] -> RnM d [a]
450 foldlRn :: (b -> a -> RnM d b) -> b -> [a] -> RnM d b
451 mapAndUnzipRn :: (a -> RnM d (b,c)) -> [a] -> RnM d ([b],[c])
452 fixRn :: (a -> RnM d a) -> RnM d a
454 returnRn v gdown ldown = return v
455 thenRn m k gdown ldown = m gdown ldown >>= \ r -> k r gdown ldown
456 thenRn_ m k gdown ldown = m gdown ldown >> k gdown ldown
457 fixRn m gdown ldown = fixIO (\r -> m r gdown ldown)
458 andRn combiner m1 m2 gdown ldown
459 = m1 gdown ldown >>= \ res1 ->
460 m2 gdown ldown >>= \ res2 ->
461 return (combiner res1 res2)
463 sequenceRn [] = returnRn []
464 sequenceRn (m:ms) = m `thenRn` \ r ->
465 sequenceRn ms `thenRn` \ rs ->
468 mapRn f [] = returnRn []
470 = f x `thenRn` \ r ->
471 mapRn f xs `thenRn` \ rs ->
474 mapRn_ f [] = returnRn ()
479 foldlRn k z [] = returnRn z
480 foldlRn k z (x:xs) = k z x `thenRn` \ z' ->
483 mapAndUnzipRn f [] = returnRn ([],[])
484 mapAndUnzipRn f (x:xs)
485 = f x `thenRn` \ (r1, r2) ->
486 mapAndUnzipRn f xs `thenRn` \ (rs1, rs2) ->
487 returnRn (r1:rs1, r2:rs2)
489 mapAndUnzip3Rn f [] = returnRn ([],[],[])
490 mapAndUnzip3Rn f (x:xs)
491 = f x `thenRn` \ (r1, r2, r3) ->
492 mapAndUnzip3Rn f xs `thenRn` \ (rs1, rs2, rs3) ->
493 returnRn (r1:rs1, r2:rs2, r3:rs3)
495 mapMaybeRn f [] = returnRn []
496 mapMaybeRn f (x:xs) = f x `thenRn` \ maybe_r ->
497 mapMaybeRn f xs `thenRn` \ rs ->
499 Nothing -> returnRn rs
500 Just r -> returnRn (r:rs)
502 flatMapRn f [] = returnRn []
503 flatMapRn f (x:xs) = f x `thenRn` \ r ->
504 flatMapRn f xs `thenRn` \ rs ->
510 %************************************************************************
512 \subsection{Boring plumbing for common part}
514 %************************************************************************
518 \subsubsection{ Errors and warnings}
519 %=====================
522 failWithRn :: a -> Message -> RnM d a
523 failWithRn res msg (RnDown {rn_errs = errs_var, rn_loc = loc}) l_down
524 = readIORef errs_var >>= \ (warns,errs) ->
525 writeIORef errs_var (warns, errs `snocBag` err) >>
528 err = addShortErrLocLine loc msg
530 warnWithRn :: a -> Message -> RnM d a
531 warnWithRn res msg (RnDown {rn_errs = errs_var, rn_loc = loc}) l_down
532 = readIORef errs_var >>= \ (warns,errs) ->
533 writeIORef errs_var (warns `snocBag` warn, errs) >>
536 warn = addShortWarnLocLine loc msg
538 addErrRn :: Message -> RnM d ()
539 addErrRn err = failWithRn () err
541 checkRn :: Bool -> Message -> RnM d () -- Check that a condition is true
542 checkRn False err = addErrRn err
543 checkRn True err = returnRn ()
545 warnCheckRn :: Bool -> Message -> RnM d () -- Check that a condition is true
546 warnCheckRn False err = addWarnRn err
547 warnCheckRn True err = returnRn ()
549 addWarnRn :: Message -> RnM d ()
550 addWarnRn warn = warnWithRn () warn
552 checkErrsRn :: RnM d Bool -- True <=> no errors so far
553 checkErrsRn (RnDown {rn_errs = errs_var}) l_down
554 = readIORef errs_var >>= \ (warns,errs) ->
555 return (isEmptyBag errs)
557 doptRn :: DynFlag -> RnM d Bool
558 doptRn dflag (RnDown { rn_dflags = dflags}) l_down
559 = return (dopt dflag dflags)
561 getDOptsRn :: RnM d DynFlags
562 getDOptsRn (RnDown { rn_dflags = dflags}) l_down
568 \subsubsection{Source location}
569 %=====================
572 pushSrcLocRn :: SrcLoc -> RnM d a -> RnM d a
573 pushSrcLocRn loc' m down l_down
574 = m (down {rn_loc = loc'}) l_down
576 getSrcLocRn :: RnM d SrcLoc
577 getSrcLocRn down l_down
578 = return (rn_loc down)
582 \subsubsection{The finder and home symbol table}
583 %=====================
586 getFinderRn :: RnM d Finder
587 getFinderRn down l_down = return (rn_finder down)
589 getHomeIfaceTableRn :: RnM d HomeIfaceTable
590 getHomeIfaceTableRn down l_down = return (rn_hit down)
592 checkAlreadyAvailable :: Name -> RnM d Bool
593 checkAlreadyAvailable name down l_down = return (rn_done down name)
597 \subsubsection{Name supply}
598 %=====================
601 getNameSupplyRn :: RnM d (UniqSupply, OrigNameNameEnv, OrigNameIParamEnv)
602 getNameSupplyRn rn_down l_down
603 = readIORef (rn_ns rn_down)
605 setNameSupplyRn :: (UniqSupply, OrigNameNameEnv, OrigNameIParamEnv) -> RnM d ()
606 setNameSupplyRn names' (RnDown {rn_ns = names_var}) l_down
607 = writeIORef names_var names'
609 getUniqRn :: RnM d Unique
610 getUniqRn (RnDown {rn_ns = names_var}) l_down
611 = readIORef names_var >>= \ (us, cache, ipcache) ->
613 (us1,us') = splitUniqSupply us
615 writeIORef names_var (us', cache, ipcache) >>
616 return (uniqFromSupply us1)
620 \subsubsection{ Module}
621 %=====================
624 getModuleRn :: RnM d Module
625 getModuleRn (RnDown {rn_mod = mod}) l_down
628 setModuleRn :: Module -> RnM d a -> RnM d a
629 setModuleRn new_mod enclosed_thing rn_down l_down
630 = enclosed_thing (rn_down {rn_mod = new_mod}) l_down
634 %************************************************************************
636 \subsection{Plumbing for rename-source part}
638 %************************************************************************
641 \subsubsection{ RnEnv}
642 %=====================
645 getLocalNameEnv :: RnMS LocalRdrEnv
646 getLocalNameEnv rn_down (SDown {rn_lenv = local_env})
649 getGlobalNameEnv :: RnMS GlobalRdrEnv
650 getGlobalNameEnv rn_down (SDown {rn_genv = global_env})
653 setLocalNameEnv :: LocalRdrEnv -> RnMS a -> RnMS a
654 setLocalNameEnv local_env' m rn_down l_down
655 = m rn_down (l_down {rn_lenv = local_env'})
657 getFixityEnv :: RnMS LocalFixityEnv
658 getFixityEnv rn_down (SDown {rn_fixenv = fixity_env})
661 extendFixityEnv :: [(Name, RenamedFixitySig)] -> RnMS a -> RnMS a
662 extendFixityEnv fixes enclosed_scope
663 rn_down l_down@(SDown {rn_fixenv = fixity_env})
665 new_fixity_env = extendNameEnvList fixity_env fixes
667 enclosed_scope rn_down (l_down {rn_fixenv = new_fixity_env})
671 \subsubsection{ Mode}
672 %=====================
675 getModeRn :: RnMS RnMode
676 getModeRn rn_down (SDown {rn_mode = mode})
679 setModeRn :: RnMode -> RnMS a -> RnMS a
680 setModeRn new_mode thing_inside rn_down l_down
681 = thing_inside rn_down (l_down {rn_mode = new_mode})
685 %************************************************************************
687 \subsection{Plumbing for rename-globals part}
689 %************************************************************************
692 getIfacesRn :: RnM d Ifaces
693 getIfacesRn (RnDown {rn_ifaces = iface_var}) _
694 = readIORef iface_var
696 setIfacesRn :: Ifaces -> RnM d ()
697 setIfacesRn ifaces (RnDown {rn_ifaces = iface_var}) _
698 = writeIORef iface_var ifaces