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, TyThing,
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(..),
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 ErrUtils ( printErrorsAndWarnings )
72 infixr 9 `thenRn`, `thenRn_`
76 %************************************************************************
78 \subsection{Somewhat magical interface to other monads}
80 %************************************************************************
83 ioToRnM :: IO r -> RnM d (Either IOError r)
84 ioToRnM io rn_down g_down = (io >>= \ ok -> return (Right ok))
86 (\ err -> return (Left err))
88 ioToRnM_no_fail :: IO r -> RnM d r
89 ioToRnM_no_fail io rn_down g_down
90 = (io >>= \ ok -> return ok)
92 (\ err -> panic "ioToRnM_no_fail: the I/O operation failed!")
94 traceRn :: SDoc -> RnM d ()
96 = doptRn Opt_D_dump_rn_trace `thenRn` \b ->
97 if b then putDocRn msg else returnRn ()
99 traceHiDiffsRn :: SDoc -> RnM d ()
101 = doptRn Opt_D_dump_hi_diffs `thenRn` \b ->
102 if b then putDocRn msg else returnRn ()
104 putDocRn :: SDoc -> RnM d ()
105 putDocRn msg = ioToRnM (printErrs msg) `thenRn_`
110 %************************************************************************
112 \subsection{Data types}
114 %************************************************************************
116 %===================================================
117 \subsubsection{ MONAD TYPES}
118 %===================================================
121 type RnM d r = RnDown -> d -> IO r
122 type RnMS r = RnM SDown r -- Renaming source
123 type RnMG r = RnM () r -- Getting global names etc
128 rn_mod :: Module, -- This module
129 rn_loc :: SrcLoc, -- Current locn
131 rn_dflags :: DynFlags,
133 rn_hit :: HomeIfaceTable,
134 rn_done :: Name -> Maybe TyThing, -- Tells what things (both in the
135 -- home package and other packages)
136 -- were already available (i.e. in
137 -- the relevant SymbolTable) before
138 -- compiling this module
139 -- The Name passed to rn_done is guaranteed to be a Global,
140 -- so it has a Module, so it can be looked up
142 rn_errs :: IORef (Bag WarnMsg, Bag ErrMsg),
144 -- The second and third components are a flattened-out OrigNameEnv
145 rn_ns :: IORef (UniqSupply, OrigNameNameEnv, OrigNameIParamEnv),
146 rn_ifaces :: IORef Ifaces
149 -- For renaming source code
153 rn_genv :: GlobalRdrEnv, -- Top level environment
155 rn_lenv :: LocalRdrEnv, -- Local name envt
156 -- Does *not* include global name envt; may shadow it
157 -- Includes both ordinary variables and type variables;
158 -- they are kept distinct because tyvar have a different
159 -- occurrence contructor (Name.TvOcc)
160 -- We still need the unsullied global name env so that
161 -- we can look up record field names
163 rn_fixenv :: LocalFixityEnv -- Local fixities (for non-top-level
165 -- The global fixities are held in the
166 -- HIT or PIT. Why? See the comments
167 -- with RnIfaces.lookupLocalFixity
170 data RnMode = SourceMode -- Renaming source code
171 | InterfaceMode -- Renaming interface declarations.
174 %===================================================
175 \subsubsection{ ENVIRONMENTS}
176 %===================================================
179 --------------------------------
180 type LocalRdrEnv = RdrNameEnv Name
181 type LocalFixityEnv = NameEnv RenamedFixitySig
182 -- We keep the whole fixity sig so that we
183 -- can report line-number info when there is a duplicate
184 -- fixity declaration
186 lookupLocalFixity :: LocalFixityEnv -> Name -> Fixity
187 lookupLocalFixity env name
188 = case lookupNameEnv env name of
189 Just (FixitySig _ fix _) -> fix
190 Nothing -> defaultFixity
194 type ExportAvails = (FiniteMap ModuleName Avails,
195 -- Used to figure out "module M" export specifiers
196 -- Includes avails only from *unqualified* imports
197 -- (see 1.4 Report Section 5.1.1)
199 AvailEnv) -- Used to figure out all other export specifiers.
202 %===================================================
203 \subsubsection{ INTERFACE FILE STUFF}
204 %===================================================
207 type ExportItem = (ModuleName, [RdrAvailInfo])
208 type IfaceDeprecs = Maybe (Either DeprecTxt [(RdrName,DeprecTxt)])
209 -- Nothing => NoDeprecs
210 -- Just (Left t) => DeprecAll
211 -- Just (Right p) => DeprecSome
215 pi_mod :: Module, -- Complete with package info
216 pi_vers :: Version, -- Module version number
217 pi_orphan :: WhetherHasOrphans, -- Whether this module has orphans
218 pi_usages :: [ImportVersion OccName], -- Usages
219 pi_exports :: (Version, [ExportItem]), -- Exports
220 pi_decls :: [(Version, RdrNameTyClDecl)], -- Local definitions
221 pi_fixity :: [RdrNameFixitySig], -- Local fixity declarations,
222 pi_insts :: [RdrNameInstDecl], -- Local instance declarations
223 pi_rules :: (Version, [RdrNameRuleDecl]), -- Rules, with their version
224 pi_deprecs :: IfaceDeprecs -- Deprecations
228 %************************************************************************
230 \subsection{The renamer state}
232 %************************************************************************
235 data Ifaces = Ifaces {
237 iPIT :: PackageIfaceTable,
238 -- The ModuleIFaces for modules in other packages
239 -- whose interfaces we have opened
240 -- The declarations in these interface files are held in
241 -- iDecls, iInsts, iRules (below), not in the mi_decls fields
242 -- of the iPIT. What _is_ in the iPIT is:
248 -- The iPIT field is initialised from the compiler's persistent
249 -- package symbol table, and the renamer incrementally adds
253 -- A single, global map of Names to unslurped decls
255 iInsts :: IfaceInsts,
256 -- The as-yet un-slurped instance decls; this bag is depleted when we
257 -- slurp an instance decl so that we don't slurp the same one twice.
258 -- Each is 'gated' by the names that must be available before
259 -- this instance decl is needed.
261 iRules :: IfaceRules,
262 -- Similar to instance decls, only for rules
265 -- These fields persist during the compilation of a single module only
266 iImpModInfo :: ImportedModuleInfo,
267 -- Modules that we know something about, because they are mentioned
268 -- in interface files, BUT which we have not loaded yet.
269 -- No module is both in here and in the PIT
272 -- All the names (whether "big" or "small", whether wired-in or not,
273 -- whether locally defined or not) that have been slurped in so far.
275 iVSlurp :: (ModuleSet, NameSet)
276 -- The Names are all the (a) non-wired-in
278 -- (c) non-locally-defined
280 -- names that have been slurped in so far, with their versions.
281 -- This is used to generate the "usage" information for this module.
282 -- Subset of the previous field.
283 -- The module set is the non-home-package modules from which we have
284 -- slurped at least one name.
285 -- It's worth keeping separately, because there's no very easy
286 -- way to distinguish the "big" names from the "non-big" ones.
287 -- But this is a decision we might want to revisit.
290 type ImportedModuleInfo = FiniteMap ModuleName (WhetherHasOrphans, IsBootInterface)
291 -- Contains info ONLY about modules that have not yet
292 --- been loaded into the iPIT
296 %************************************************************************
298 \subsection{Main monad code}
300 %************************************************************************
304 -> HomeIfaceTable -> HomeSymbolTable
305 -> PersistentCompilerState
308 -> IO (PersistentCompilerState, Bool, t)
309 -- True <=> found errors
311 initRn dflags hit hst pcs mod do_rn
313 let prs = pcs_PRS pcs
314 let pte = pcs_PTE pcs
315 let ifaces = Ifaces { iPIT = pcs_PIT pcs,
316 iDecls = prsDecls prs,
317 iInsts = prsInsts prs,
318 iRules = prsRules prs,
320 iImpModInfo = emptyFM,
321 iSlurp = unitNameSet (mkUnboundName dummyRdrVarName),
322 -- Pretend that the dummy unbound name has already been
323 -- slurped. This is what's returned for an out-of-scope name,
324 -- and we don't want thereby to try to suck it in!
325 iVSlurp = (emptyModuleSet, emptyNameSet)
327 let uniqs = prsNS prs
329 names_var <- newIORef (uniqs, origNames (prsOrig prs),
330 origIParam (prsOrig prs))
331 errs_var <- newIORef (emptyBag,emptyBag)
332 iface_var <- newIORef ifaces
333 let rn_down = RnDown { rn_mod = mod,
338 rn_done = lookupType hst pte,
342 rn_ifaces = iface_var,
346 res <- do_rn rn_down ()
348 -- Grab state and record it
349 (warns, errs) <- readIORef errs_var
350 new_ifaces <- readIORef iface_var
351 (new_NS, new_origN, new_origIP) <- readIORef names_var
352 let new_orig = Orig { origNames = new_origN, origIParam = new_origIP }
353 let new_prs = prs { prsOrig = new_orig,
354 prsDecls = iDecls new_ifaces,
355 prsInsts = iInsts new_ifaces,
356 prsRules = iRules new_ifaces,
358 let new_pcs = pcs { pcs_PIT = iPIT new_ifaces,
361 -- Check for warnings
362 printErrorsAndWarnings (warns, errs) ;
364 return (new_pcs, not (isEmptyBag errs), res)
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 sequenceRn_ :: [RnM d a] -> RnM d ()
454 foldlRn :: (b -> a -> RnM d b) -> b -> [a] -> RnM d b
455 mapAndUnzipRn :: (a -> RnM d (b,c)) -> [a] -> RnM d ([b],[c])
456 fixRn :: (a -> RnM d a) -> RnM d a
458 returnRn v gdown ldown = return v
459 thenRn m k gdown ldown = m gdown ldown >>= \ r -> k r gdown ldown
460 thenRn_ m k gdown ldown = m gdown ldown >> k gdown ldown
461 fixRn m gdown ldown = fixIO (\r -> m r gdown ldown)
462 andRn combiner m1 m2 gdown ldown
463 = m1 gdown ldown >>= \ res1 ->
464 m2 gdown ldown >>= \ res2 ->
465 return (combiner res1 res2)
467 sequenceRn [] = returnRn []
468 sequenceRn (m:ms) = m `thenRn` \ r ->
469 sequenceRn ms `thenRn` \ rs ->
472 sequenceRn_ [] = returnRn ()
473 sequenceRn_ (m:ms) = m `thenRn_` sequenceRn_ ms
475 mapRn f [] = returnRn []
477 = f x `thenRn` \ r ->
478 mapRn f xs `thenRn` \ rs ->
481 mapRn_ f [] = returnRn ()
486 foldlRn k z [] = returnRn z
487 foldlRn k z (x:xs) = k z x `thenRn` \ z' ->
490 mapAndUnzipRn f [] = returnRn ([],[])
491 mapAndUnzipRn f (x:xs)
492 = f x `thenRn` \ (r1, r2) ->
493 mapAndUnzipRn f xs `thenRn` \ (rs1, rs2) ->
494 returnRn (r1:rs1, r2:rs2)
496 mapAndUnzip3Rn f [] = returnRn ([],[],[])
497 mapAndUnzip3Rn f (x:xs)
498 = f x `thenRn` \ (r1, r2, r3) ->
499 mapAndUnzip3Rn f xs `thenRn` \ (rs1, rs2, rs3) ->
500 returnRn (r1:rs1, r2:rs2, r3:rs3)
502 mapMaybeRn f [] = returnRn []
503 mapMaybeRn f (x:xs) = f x `thenRn` \ maybe_r ->
504 mapMaybeRn f xs `thenRn` \ rs ->
506 Nothing -> returnRn rs
507 Just r -> returnRn (r:rs)
509 flatMapRn f [] = returnRn []
510 flatMapRn f (x:xs) = f x `thenRn` \ r ->
511 flatMapRn f xs `thenRn` \ rs ->
517 %************************************************************************
519 \subsection{Boring plumbing for common part}
521 %************************************************************************
525 \subsubsection{ Errors and warnings}
526 %=====================
529 failWithRn :: a -> Message -> RnM d a
530 failWithRn res msg (RnDown {rn_errs = errs_var, rn_loc = loc}) l_down
531 = readIORef errs_var >>= \ (warns,errs) ->
532 writeIORef errs_var (warns, errs `snocBag` err) >>
535 err = addShortErrLocLine loc msg
537 warnWithRn :: a -> Message -> RnM d a
538 warnWithRn res msg (RnDown {rn_errs = errs_var, rn_loc = loc}) l_down
539 = readIORef errs_var >>= \ (warns,errs) ->
540 writeIORef errs_var (warns `snocBag` warn, errs) >>
543 warn = addShortWarnLocLine loc msg
545 addErrRn :: Message -> RnM d ()
546 addErrRn err = failWithRn () err
548 checkRn :: Bool -> Message -> RnM d () -- Check that a condition is true
549 checkRn False err = addErrRn err
550 checkRn True err = returnRn ()
552 warnCheckRn :: Bool -> Message -> RnM d () -- Check that a condition is true
553 warnCheckRn False err = addWarnRn err
554 warnCheckRn True err = returnRn ()
556 addWarnRn :: Message -> RnM d ()
557 addWarnRn warn = warnWithRn () warn
559 checkErrsRn :: RnM d Bool -- True <=> no errors so far
560 checkErrsRn (RnDown {rn_errs = errs_var}) l_down
561 = readIORef errs_var >>= \ (warns,errs) ->
562 return (isEmptyBag errs)
564 doptRn :: DynFlag -> RnM d Bool
565 doptRn dflag (RnDown { rn_dflags = dflags}) l_down
566 = return (dopt dflag dflags)
568 getDOptsRn :: RnM d DynFlags
569 getDOptsRn (RnDown { rn_dflags = dflags}) l_down
575 \subsubsection{Source location}
576 %=====================
579 pushSrcLocRn :: SrcLoc -> RnM d a -> RnM d a
580 pushSrcLocRn loc' m down l_down
581 = m (down {rn_loc = loc'}) l_down
583 getSrcLocRn :: RnM d SrcLoc
584 getSrcLocRn down l_down
585 = return (rn_loc down)
589 \subsubsection{The finder and home symbol table}
590 %=====================
593 getHomeIfaceTableRn :: RnM d HomeIfaceTable
594 getHomeIfaceTableRn down l_down = return (rn_hit down)
596 getTypeEnvRn :: RnM d (Name -> Maybe TyThing)
597 getTypeEnvRn down l_down = return (rn_done down)
601 \subsubsection{Name supply}
602 %=====================
605 getNameSupplyRn :: RnM d (UniqSupply, OrigNameNameEnv, OrigNameIParamEnv)
606 getNameSupplyRn rn_down l_down
607 = readIORef (rn_ns rn_down)
609 setNameSupplyRn :: (UniqSupply, OrigNameNameEnv, OrigNameIParamEnv) -> RnM d ()
610 setNameSupplyRn names' (RnDown {rn_ns = names_var}) l_down
611 = writeIORef names_var names'
613 getUniqRn :: RnM d Unique
614 getUniqRn (RnDown {rn_ns = names_var}) l_down
615 = readIORef names_var >>= \ (us, cache, ipcache) ->
617 (us1,us') = splitUniqSupply us
619 writeIORef names_var (us', cache, ipcache) >>
620 return (uniqFromSupply us1)
624 \subsubsection{ Module}
625 %=====================
628 getModuleRn :: RnM d Module
629 getModuleRn (RnDown {rn_mod = mod}) l_down
632 setModuleRn :: Module -> RnM d a -> RnM d a
633 setModuleRn new_mod enclosed_thing rn_down l_down
634 = enclosed_thing (rn_down {rn_mod = new_mod}) l_down
638 %************************************************************************
640 \subsection{Plumbing for rename-source part}
642 %************************************************************************
645 \subsubsection{ RnEnv}
646 %=====================
649 getLocalNameEnv :: RnMS LocalRdrEnv
650 getLocalNameEnv rn_down (SDown {rn_lenv = local_env})
653 getGlobalNameEnv :: RnMS GlobalRdrEnv
654 getGlobalNameEnv rn_down (SDown {rn_genv = global_env})
657 setLocalNameEnv :: LocalRdrEnv -> RnMS a -> RnMS a
658 setLocalNameEnv local_env' m rn_down l_down
659 = m rn_down (l_down {rn_lenv = local_env'})
661 getFixityEnv :: RnMS LocalFixityEnv
662 getFixityEnv rn_down (SDown {rn_fixenv = fixity_env})
665 extendFixityEnv :: [(Name, RenamedFixitySig)] -> RnMS a -> RnMS a
666 extendFixityEnv fixes enclosed_scope
667 rn_down l_down@(SDown {rn_fixenv = fixity_env})
669 new_fixity_env = extendNameEnvList fixity_env fixes
671 enclosed_scope rn_down (l_down {rn_fixenv = new_fixity_env})
675 \subsubsection{ Mode}
676 %=====================
679 getModeRn :: RnMS RnMode
680 getModeRn rn_down (SDown {rn_mode = mode})
683 setModeRn :: RnMode -> RnMS a -> RnMS a
684 setModeRn new_mode thing_inside rn_down l_down
685 = thing_inside rn_down (l_down {rn_mode = new_mode})
689 %************************************************************************
691 \subsection{Plumbing for rename-globals part}
693 %************************************************************************
696 getIfacesRn :: RnM d Ifaces
697 getIfacesRn (RnDown {rn_ifaces = iface_var}) _
698 = readIORef iface_var
700 setIfacesRn :: Ifaces -> RnM d ()
701 setIfacesRn ifaces (RnDown {rn_ifaces = iface_var}) _
702 = writeIORef iface_var ifaces