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 ( AvailEnv, lookupType,
39 OrigNameEnv(..), OrigNameNameEnv, OrigNameIParamEnv,
40 WhetherHasOrphans, ImportVersion,
41 PersistentRenamerState(..), IsBootInterface, Avails,
42 DeclsMap, IfaceInsts, IfaceRules,
43 HomeSymbolTable, PackageTypeEnv,
44 PersistentCompilerState(..), GlobalRdrEnv,
45 HomeIfaceTable, PackageIfaceTable,
47 import BasicTypes ( Version, defaultFixity )
48 import ErrUtils ( addShortErrLocLine, addShortWarnLocLine,
49 pprBagOfErrors, ErrMsg, WarnMsg, Message
51 import RdrName ( RdrName, dummyRdrVarName, rdrNameModule, rdrNameOcc,
52 RdrNameEnv, emptyRdrEnv, extendRdrEnv,
53 addListToRdrEnv, rdrEnvToList, rdrEnvElts
55 import Name ( Name, OccName, NamedThing(..), getSrcLoc,
57 decode, mkLocalName, mkKnownKeyGlobal
59 import Name ( NameEnv, lookupNameEnv, emptyNameEnv, unitNameEnv, extendNameEnvList )
60 import Module ( Module, ModuleName, ModuleSet, emptyModuleSet )
62 import CmdLineOpts ( DynFlags, DynFlag(..), dopt )
63 import SrcLoc ( SrcLoc, generatedSrcLoc, noSrcLoc )
64 import Unique ( Unique )
65 import FiniteMap ( FiniteMap, emptyFM )
66 import Bag ( Bag, emptyBag, isEmptyBag, snocBag )
69 import PrelNames ( mkUnboundName )
70 import Maybes ( maybeToBool )
71 import ErrUtils ( printErrorsAndWarnings )
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 putDocRn :: SDoc -> RnM d ()
101 putDocRn msg = ioToRnM (printErrs msg) `thenRn_`
106 %************************************************************************
108 \subsection{Data types}
110 %************************************************************************
112 %===================================================
113 \subsubsection{ MONAD TYPES}
114 %===================================================
117 type RnM d r = RnDown -> d -> IO r
118 type RnMS r = RnM SDown r -- Renaming source
119 type RnMG r = RnM () r -- Getting global names etc
124 rn_mod :: Module, -- This module
125 rn_loc :: SrcLoc, -- Current locn
127 rn_dflags :: DynFlags,
129 rn_hit :: HomeIfaceTable,
130 rn_done :: Name -> Bool, -- Tells what things (both in the
131 -- home package and other packages)
132 -- were already available (i.e. in
133 -- the relevant SymbolTable) before
134 -- compiling this module
136 rn_errs :: IORef (Bag WarnMsg, Bag ErrMsg),
138 -- The second and third components are a flattened-out OrigNameEnv
139 rn_ns :: IORef (UniqSupply, OrigNameNameEnv, OrigNameIParamEnv),
140 rn_ifaces :: IORef Ifaces
143 -- For renaming source code
147 rn_genv :: GlobalRdrEnv, -- Top level environment
149 rn_lenv :: LocalRdrEnv, -- Local name envt
150 -- Does *not* include global name envt; may shadow it
151 -- Includes both ordinary variables and type variables;
152 -- they are kept distinct because tyvar have a different
153 -- occurrence contructor (Name.TvOcc)
154 -- We still need the unsullied global name env so that
155 -- we can look up record field names
157 rn_fixenv :: LocalFixityEnv -- Local fixities (for non-top-level
159 -- The global fixities are held in the
160 -- HIT or PIT. Why? See the comments
161 -- with RnIfaces.lookupLocalFixity
164 data RnMode = SourceMode -- Renaming source code
165 | InterfaceMode -- Renaming interface declarations.
168 %===================================================
169 \subsubsection{ ENVIRONMENTS}
170 %===================================================
173 --------------------------------
174 type LocalRdrEnv = RdrNameEnv Name
175 type LocalFixityEnv = NameEnv RenamedFixitySig
176 -- We keep the whole fixity sig so that we
177 -- can report line-number info when there is a duplicate
178 -- fixity declaration
180 lookupLocalFixity :: LocalFixityEnv -> Name -> Fixity
181 lookupLocalFixity env name
182 = case lookupNameEnv env name of
183 Just (FixitySig _ fix _) -> fix
184 Nothing -> defaultFixity
188 type ExportAvails = (FiniteMap ModuleName Avails,
189 -- Used to figure out "module M" export specifiers
190 -- Includes avails only from *unqualified* imports
191 -- (see 1.4 Report Section 5.1.1)
193 AvailEnv) -- Used to figure out all other export specifiers.
196 %===================================================
197 \subsubsection{ INTERFACE FILE STUFF}
198 %===================================================
201 type ExportItem = (ModuleName, [RdrAvailInfo])
202 type IfaceDeprecs = Maybe (Either DeprecTxt [(RdrName,DeprecTxt)])
203 -- Nothing => NoDeprecs
204 -- Just (Left t) => DeprecAll
205 -- Just (Right p) => DeprecSome
209 pi_mod :: Module, -- Complete with package info
210 pi_vers :: Version, -- Module version number
211 pi_orphan :: WhetherHasOrphans, -- Whether this module has orphans
212 pi_usages :: [ImportVersion OccName], -- Usages
213 pi_exports :: (Version, [ExportItem]), -- Exports
214 pi_decls :: [(Version, RdrNameTyClDecl)], -- Local definitions
215 pi_fixity :: [RdrNameFixitySig], -- Local fixity declarations,
216 pi_insts :: [RdrNameInstDecl], -- Local instance declarations
217 pi_rules :: (Version, [RdrNameRuleDecl]), -- Rules, with their version
218 pi_deprecs :: IfaceDeprecs -- Deprecations
222 %************************************************************************
224 \subsection{The renamer state}
226 %************************************************************************
229 data Ifaces = Ifaces {
231 iPIT :: PackageIfaceTable,
232 -- The ModuleIFaces for modules in other packages
233 -- whose interfaces we have opened
234 -- The declarations in these interface files are held in
235 -- iDecls, iInsts, iRules (below), not in the mi_decls fields
236 -- of the iPIT. What _is_ in the iPIT is:
242 -- The iPIT field is initialised from the compiler's persistent
243 -- package symbol table, and the renamer incrementally adds
247 -- A single, global map of Names to unslurped decls
249 iInsts :: IfaceInsts,
250 -- The as-yet un-slurped instance decls; this bag is depleted when we
251 -- slurp an instance decl so that we don't slurp the same one twice.
252 -- Each is 'gated' by the names that must be available before
253 -- this instance decl is needed.
255 iRules :: IfaceRules,
256 -- Similar to instance decls, only for rules
259 -- These fields persist during the compilation of a single module only
260 iImpModInfo :: ImportedModuleInfo,
261 -- Modules this one depends on: that is, the union
262 -- of the modules its *direct* imports depend on.
263 -- NB: The direct imports have .hi files that enumerate *all* the
264 -- dependencies (direct or not) of the imported module.
267 -- All the names (whether "big" or "small", whether wired-in or not,
268 -- whether locally defined or not) that have been slurped in so far.
270 iVSlurp :: (ModuleSet, NameSet)
271 -- The Names are all the (a) non-wired-in
273 -- (c) non-locally-defined
275 -- names that have been slurped in so far, with their versions.
276 -- This is used to generate the "usage" information for this module.
277 -- Subset of the previous field.
278 -- The module set is the non-home-package modules from which we have
279 -- slurped at least one name.
280 -- It's worth keeping separately, because there's no very easy
281 -- way to distinguish the "big" names from the "non-big" ones.
282 -- But this is a decision we might want to revisit.
285 type ImportedModuleInfo = FiniteMap ModuleName (WhetherHasOrphans, IsBootInterface)
286 -- Contains info ONLY about modules that have not yet
287 --- been loaded into the iPIT
291 %************************************************************************
293 \subsection{Main monad code}
295 %************************************************************************
299 -> HomeIfaceTable -> HomeSymbolTable
300 -> PersistentCompilerState
303 -> IO (PersistentCompilerState, Bool, t)
304 -- True <=> found errors
306 initRn dflags hit hst pcs mod do_rn
308 let prs = pcs_PRS pcs
309 let pte = pcs_PTE pcs
310 let ifaces = Ifaces { iPIT = pcs_PIT pcs,
311 iDecls = prsDecls prs,
312 iInsts = prsInsts prs,
313 iRules = prsRules prs,
315 iImpModInfo = emptyFM,
316 iSlurp = unitNameSet (mkUnboundName dummyRdrVarName),
317 -- Pretend that the dummy unbound name has already been
318 -- slurped. This is what's returned for an out-of-scope name,
319 -- and we don't want thereby to try to suck it in!
320 iVSlurp = (emptyModuleSet, emptyNameSet)
322 let uniqs = prsNS prs
324 names_var <- newIORef (uniqs, origNames (prsOrig prs),
325 origIParam (prsOrig prs))
326 errs_var <- newIORef (emptyBag,emptyBag)
327 iface_var <- newIORef ifaces
328 let rn_down = RnDown { rn_mod = mod,
333 rn_done = is_done hst pte,
337 rn_ifaces = iface_var,
341 res <- do_rn rn_down ()
343 -- Grab state and record it
344 (warns, errs) <- readIORef errs_var
345 new_ifaces <- readIORef iface_var
346 (new_NS, new_origN, new_origIP) <- readIORef names_var
347 let new_orig = Orig { origNames = new_origN, origIParam = new_origIP }
348 let new_prs = prs { prsOrig = new_orig,
349 prsDecls = iDecls new_ifaces,
350 prsInsts = iInsts new_ifaces,
351 prsRules = iRules new_ifaces,
353 let new_pcs = pcs { pcs_PIT = iPIT new_ifaces,
356 -- Check for warnings
357 printErrorsAndWarnings (warns, errs) ;
359 return (new_pcs, not (isEmptyBag errs), res)
361 is_done :: HomeSymbolTable -> PackageTypeEnv -> Name -> Bool
362 -- Returns True iff the name is in either symbol table
363 -- The name is a Global, so it has a Module
364 is_done hst pte n = maybeToBool (lookupType hst pte n)
366 initRnMS rn_env fixity_env mode thing_inside rn_down g_down
367 -- The fixity_env appears in both the rn_fixenv field
368 -- and in the HIT. See comments with RnHiFiles.lookupFixityRn
370 s_down = SDown { rn_genv = rn_env, rn_lenv = emptyRdrEnv,
371 rn_fixenv = fixity_env, rn_mode = mode }
373 thing_inside rn_down s_down
375 initIfaceRnMS :: Module -> RnMS r -> RnM d r
376 initIfaceRnMS mod thing_inside
377 = initRnMS emptyRdrEnv emptyNameEnv InterfaceMode $
378 setModuleRn mod thing_inside
381 @renameSourceCode@ is used to rename stuff ``out-of-line'';
382 that is, not as part of the main renamer.
383 Sole examples: derived definitions,
384 which are only generated in the type checker.
386 The @NameSupply@ includes a @UniqueSupply@, so if you call it more than
387 once you must either split it, or install a fresh unique supply.
390 renameSourceCode :: DynFlags
392 -> PersistentRenamerState
396 renameSourceCode dflags mod prs m
398 -- It's not really unsafe! When renaming source code we
399 -- only do any I/O if we need to read in a fixity declaration;
400 -- and that doesn't happen in pragmas etc
402 mkSplitUniqSupply 'r' >>= \ new_us ->
403 newIORef (new_us, origNames (prsOrig prs),
404 origIParam (prsOrig prs)) >>= \ names_var ->
405 newIORef (emptyBag,emptyBag) >>= \ errs_var ->
407 rn_down = RnDown { rn_dflags = dflags,
408 rn_loc = generatedSrcLoc, rn_ns = names_var,
411 rn_done = bogus "rn_done", rn_hit = bogus "rn_hit",
412 rn_ifaces = bogus "rn_ifaces"
414 s_down = SDown { rn_mode = InterfaceMode,
415 -- So that we can refer to PrelBase.True etc
416 rn_genv = emptyRdrEnv, rn_lenv = emptyRdrEnv,
417 rn_fixenv = emptyNameEnv }
419 m rn_down s_down >>= \ result ->
421 readIORef errs_var >>= \ (warns,errs) ->
423 (if not (isEmptyBag errs) then
424 pprTrace "Urk! renameSourceCode found errors" (display errs)
426 else if not (isEmptyBag warns) then
427 pprTrace "Note: renameSourceCode found warnings" (display warns)
435 display errs = pprBagOfErrors errs
437 bogus s = panic ("rnameSourceCode: " ++ s) -- Used for unused record fields
439 {-# INLINE thenRn #-}
440 {-# INLINE thenRn_ #-}
441 {-# INLINE returnRn #-}
444 returnRn :: a -> RnM d a
445 thenRn :: RnM d a -> (a -> RnM d b) -> RnM d b
446 thenRn_ :: RnM d a -> RnM d b -> RnM d b
447 andRn :: (a -> a -> a) -> RnM d a -> RnM d a -> RnM d a
448 mapRn :: (a -> RnM d b) -> [a] -> RnM d [b]
449 mapRn_ :: (a -> RnM d b) -> [a] -> RnM d ()
450 mapMaybeRn :: (a -> RnM d (Maybe b)) -> [a] -> RnM d [b]
451 flatMapRn :: (a -> RnM d [b]) -> [a] -> RnM d [b]
452 sequenceRn :: [RnM d a] -> RnM d [a]
453 foldlRn :: (b -> a -> RnM d b) -> b -> [a] -> RnM d b
454 mapAndUnzipRn :: (a -> RnM d (b,c)) -> [a] -> RnM d ([b],[c])
455 fixRn :: (a -> RnM d a) -> RnM d a
457 returnRn v gdown ldown = return v
458 thenRn m k gdown ldown = m gdown ldown >>= \ r -> k r gdown ldown
459 thenRn_ m k gdown ldown = m gdown ldown >> k gdown ldown
460 fixRn m gdown ldown = fixIO (\r -> m r gdown ldown)
461 andRn combiner m1 m2 gdown ldown
462 = m1 gdown ldown >>= \ res1 ->
463 m2 gdown ldown >>= \ res2 ->
464 return (combiner res1 res2)
466 sequenceRn [] = returnRn []
467 sequenceRn (m:ms) = m `thenRn` \ r ->
468 sequenceRn ms `thenRn` \ rs ->
471 mapRn f [] = returnRn []
473 = f x `thenRn` \ r ->
474 mapRn f xs `thenRn` \ rs ->
477 mapRn_ f [] = returnRn ()
482 foldlRn k z [] = returnRn z
483 foldlRn k z (x:xs) = k z x `thenRn` \ z' ->
486 mapAndUnzipRn f [] = returnRn ([],[])
487 mapAndUnzipRn f (x:xs)
488 = f x `thenRn` \ (r1, r2) ->
489 mapAndUnzipRn f xs `thenRn` \ (rs1, rs2) ->
490 returnRn (r1:rs1, r2:rs2)
492 mapAndUnzip3Rn f [] = returnRn ([],[],[])
493 mapAndUnzip3Rn f (x:xs)
494 = f x `thenRn` \ (r1, r2, r3) ->
495 mapAndUnzip3Rn f xs `thenRn` \ (rs1, rs2, rs3) ->
496 returnRn (r1:rs1, r2:rs2, r3:rs3)
498 mapMaybeRn f [] = returnRn []
499 mapMaybeRn f (x:xs) = f x `thenRn` \ maybe_r ->
500 mapMaybeRn f xs `thenRn` \ rs ->
502 Nothing -> returnRn rs
503 Just r -> returnRn (r:rs)
505 flatMapRn f [] = returnRn []
506 flatMapRn f (x:xs) = f x `thenRn` \ r ->
507 flatMapRn f xs `thenRn` \ rs ->
513 %************************************************************************
515 \subsection{Boring plumbing for common part}
517 %************************************************************************
521 \subsubsection{ Errors and warnings}
522 %=====================
525 failWithRn :: a -> Message -> RnM d a
526 failWithRn res msg (RnDown {rn_errs = errs_var, rn_loc = loc}) l_down
527 = readIORef errs_var >>= \ (warns,errs) ->
528 writeIORef errs_var (warns, errs `snocBag` err) >>
531 err = addShortErrLocLine loc msg
533 warnWithRn :: a -> Message -> RnM d a
534 warnWithRn res msg (RnDown {rn_errs = errs_var, rn_loc = loc}) l_down
535 = readIORef errs_var >>= \ (warns,errs) ->
536 writeIORef errs_var (warns `snocBag` warn, errs) >>
539 warn = addShortWarnLocLine loc msg
541 addErrRn :: Message -> RnM d ()
542 addErrRn err = failWithRn () err
544 checkRn :: Bool -> Message -> RnM d () -- Check that a condition is true
545 checkRn False err = addErrRn err
546 checkRn True err = returnRn ()
548 warnCheckRn :: Bool -> Message -> RnM d () -- Check that a condition is true
549 warnCheckRn False err = addWarnRn err
550 warnCheckRn True err = returnRn ()
552 addWarnRn :: Message -> RnM d ()
553 addWarnRn warn = warnWithRn () warn
555 checkErrsRn :: RnM d Bool -- True <=> no errors so far
556 checkErrsRn (RnDown {rn_errs = errs_var}) l_down
557 = readIORef errs_var >>= \ (warns,errs) ->
558 return (isEmptyBag errs)
560 doptRn :: DynFlag -> RnM d Bool
561 doptRn dflag (RnDown { rn_dflags = dflags}) l_down
562 = return (dopt dflag dflags)
564 getDOptsRn :: RnM d DynFlags
565 getDOptsRn (RnDown { rn_dflags = dflags}) l_down
571 \subsubsection{Source location}
572 %=====================
575 pushSrcLocRn :: SrcLoc -> RnM d a -> RnM d a
576 pushSrcLocRn loc' m down l_down
577 = m (down {rn_loc = loc'}) l_down
579 getSrcLocRn :: RnM d SrcLoc
580 getSrcLocRn down l_down
581 = return (rn_loc down)
585 \subsubsection{The finder and home symbol table}
586 %=====================
589 getHomeIfaceTableRn :: RnM d HomeIfaceTable
590 getHomeIfaceTableRn down l_down = return (rn_hit down)
592 checkAlreadyAvailable :: Name -> RnM d Bool
593 -- Name is a Global name
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