2 % (c) The University of Glasgow, 2000
4 \section[HscTypes]{Types for the per-module compiler}
11 ModDetails(..), ModIface(..),
12 ModGuts(..), ModImports(..), ForeignStubs(..),
13 ParsedIface(..), IfaceDeprecs,
15 HomePackageTable, HomeModInfo(..), emptyHomePackageTable,
17 ExternalPackageState(..),
18 PackageTypeEnv, PackageIfaceTable, emptyPackageIfaceTable,
19 lookupIface, lookupIfaceByModName, moduleNameToModule,
22 InteractiveContext(..), emptyInteractiveContext, icPrintUnqual,
24 IfaceDecls, mkIfaceDecls, dcl_tycl, dcl_rules, dcl_insts,
26 VersionInfo(..), initialVersionInfo, lookupVersion,
27 FixityEnv, lookupFixity, collectFixities, emptyFixityEnv,
29 TyThing(..), isTyClThing, implicitTyThingIds,
31 TypeEnv, lookupType, mkTypeEnv, emptyTypeEnv,
32 extendTypeEnvList, extendTypeEnvWithIds,
33 typeEnvElts, typeEnvClasses, typeEnvTyCons, typeEnvIds,
35 ImportedModuleInfo, WhetherHasOrphans, ImportVersion, WhatsImported(..),
36 IsBootInterface, DeclsMap,
37 IfaceInsts, IfaceRules, GatedDecl, GatedDecls, GateFn,
38 NameCache(..), OrigNameCache, OrigIParamCache,
39 Avails, availsToNameSet, availName, availNames,
40 GenAvailInfo(..), AvailInfo, RdrAvailInfo,
41 ExportItem, RdrExportItem,
43 PersistentCompilerState(..),
45 Deprecations(..), lookupDeprec, plusDeprecs,
47 InstEnv, ClsInstEnv, DFunId,
48 PackageInstEnv, PackageRuleBase,
50 GlobalRdrEnv, GlobalRdrElt(..), emptyGlobalRdrEnv, pprGlobalRdrEnv,
51 LocalRdrEnv, extendLocalRdrEnv, isLocalGRE, unQualInScope,
54 Linkable(..), isObjectLinkable,
55 Unlinked(..), CompiledByteCode,
56 isObject, nameOfObject, isInterpretable, byteCodeOfObject,
59 Provenance(..), ImportReason(..),
60 pprNameProvenance, hasBetterProv
64 #include "HsVersions.h"
67 import ByteCodeAsm ( CompiledByteCode )
70 import RdrName ( RdrName, mkRdrUnqual,
71 RdrNameEnv, addListToRdrEnv, foldRdrEnv, isUnqual,
72 rdrEnvToList, emptyRdrEnv )
73 import Name ( Name, NamedThing, getName, nameOccName, nameModule, nameSrcLoc )
76 import OccName ( OccName )
78 import InstEnv ( InstEnv, ClsInstEnv, DFunId )
79 import Rules ( RuleBase )
80 import CoreSyn ( CoreBind )
82 import Class ( Class, classSelIds )
83 import TyCon ( TyCon, isNewTyCon, tyConGenIds, tyConSelIds, tyConDataCons_maybe )
84 import DataCon ( dataConWorkId, dataConWrapId )
85 import Packages ( PackageName, preludePackage )
86 import CmdLineOpts ( DynFlags )
88 import BasicTypes ( Version, initialVersion, IPName,
89 Fixity, FixitySig(..), defaultFixity )
91 import HsSyn ( DeprecTxt, TyClDecl, InstDecl, RuleDecl,
92 tyClDeclName, ifaceRuleDeclName, tyClDeclNames )
93 import RnHsSyn ( RenamedTyClDecl, RenamedRuleDecl, RenamedInstDecl )
95 import CoreSyn ( IdCoreRule )
96 import PrelNames ( isBuiltInSyntaxName )
100 import Maybes ( orElse )
102 import SrcLoc ( SrcLoc, isGoodSrcLoc )
103 import Util ( thenCmp, sortLt )
104 import UniqSupply ( UniqSupply )
105 import Maybe ( fromJust )
106 import FastString ( FastString )
108 import Time ( ClockTime )
112 %************************************************************************
114 \subsection{Compilation environment}
116 %************************************************************************
118 The HscEnv gives the environment in which to compile a chunk of code.
121 data HscEnv = HscEnv { hsc_mode :: GhciMode,
122 hsc_dflags :: DynFlags,
123 hsc_HPT :: HomePackageTable }
126 The GhciMode is self-explanatory:
129 data GhciMode = Batch | Interactive | OneShot
134 type HomePackageTable = ModuleEnv HomeModInfo -- Domain = modules in the home package
135 type PackageIfaceTable = ModuleEnv ModIface -- Domain = modules in the imported packages
137 emptyHomePackageTable = emptyModuleEnv
138 emptyPackageIfaceTable = emptyModuleEnv
140 data HomeModInfo = HomeModInfo { hm_iface :: ModIface,
141 hm_details :: ModDetails,
142 hm_linkable :: Linkable }
145 Simple lookups in the symbol table.
148 lookupIface :: HomePackageTable -> PackageIfaceTable -> Name -> Maybe ModIface
149 -- We often have two IfaceTables, and want to do a lookup
150 lookupIface hpt pit name
151 = case lookupModuleEnv hpt mod of
152 Just mod_info -> Just (hm_iface mod_info)
153 Nothing -> lookupModuleEnv pit mod
155 mod = nameModule name
157 lookupIfaceByModName :: HomePackageTable -> PackageIfaceTable -> ModuleName -> Maybe ModIface
158 -- We often have two IfaceTables, and want to do a lookup
159 lookupIfaceByModName hpt pit mod
160 = case lookupModuleEnvByName hpt mod of
161 Just mod_info -> Just (hm_iface mod_info)
162 Nothing -> lookupModuleEnvByName pit mod
166 -- Use instead of Finder.findModule if possible: this way doesn't
167 -- require filesystem operations, and it is guaranteed not to fail
168 -- when the IfaceTables are properly populated (i.e. after the renamer).
169 moduleNameToModule :: HomePackageTable -> PackageIfaceTable -> ModuleName -> Module
170 moduleNameToModule hpt pit mod
171 = mi_module (fromJust (lookupIfaceByModName hpt pit mod))
175 %************************************************************************
177 \subsection{Symbol tables and Module details}
179 %************************************************************************
181 A @ModIface@ plus a @ModDetails@ summarises everything we know
182 about a compiled module. The @ModIface@ is the stuff *before* linking,
183 and can be written out to an interface file. (The @ModDetails@ is after
184 linking; it is the "linked" form of the mi_decls field.)
186 When we *read* an interface file, we also construct a @ModIface@ from it,
187 except that the mi_decls part is empty; when reading we consolidate
188 the declarations into a single indexed map in the @PersistentRenamerState@.
193 mi_module :: !Module,
194 mi_package :: !PackageName, -- Which package the module comes from
195 mi_version :: !VersionInfo, -- Module version number
196 mi_orphan :: !WhetherHasOrphans, -- Whether this module has orphans
197 mi_boot :: !IsBootInterface, -- Read from an hi-boot file?
199 mi_usages :: [ImportVersion Name],
200 -- Usages; kept sorted so that it's easy to decide
201 -- whether to write a new iface file (changing usages
202 -- doesn't affect the version of this module)
203 -- NOT STRICT! we read this field lazily from the interface file
205 mi_exports :: ![ExportItem],
206 -- What it exports Kept sorted by (mod,occ), to make
207 -- version comparisons easier
209 mi_globals :: !(Maybe GlobalRdrEnv),
210 -- Its top level environment or Nothing if we read this
211 -- interface from an interface file. (We need the source
212 -- file to figure out the top-level environment.)
214 mi_fixities :: !FixityEnv, -- Fixities
215 mi_deprecs :: Deprecations, -- Deprecations
216 -- NOT STRICT! we read this field lazilly from the interface file
218 mi_decls :: IfaceDecls -- The RnDecls form of ModDetails
219 -- NOT STRICT! we fill this field with _|_ sometimes
222 -- Should be able to construct ModDetails from mi_decls in ModIface
225 -- The next three fields are created by the typechecker
226 md_types :: !TypeEnv,
227 md_insts :: ![DFunId], -- Dfun-ids for the instances in this module
228 md_rules :: ![IdCoreRule] -- Domain may include Ids from other modules
233 -- A ModGuts is carried through the compiler, accumulating stuff as it goes
234 -- There is only one ModGuts at any time, the one for the module
235 -- being compiled right now. Once it is compiled, a ModIface and
236 -- ModDetails are extracted and the ModGuts is dicarded.
240 mg_module :: !Module,
241 mg_exports :: !Avails, -- What it exports
242 mg_usages :: ![ImportVersion Name], -- What it imports, directly or otherwise
243 -- ...exactly as in ModIface
244 mg_dir_imps :: ![Module], -- Directly imported modules
246 mg_rdr_env :: !GlobalRdrEnv, -- Top-level lexical environment
247 mg_fix_env :: !FixityEnv, -- Fixity env, for things declared in this module
248 mg_deprecs :: !Deprecations, -- Deprecations declared in the module
250 mg_types :: !TypeEnv,
251 mg_insts :: ![DFunId], -- Instances
252 mg_rules :: ![IdCoreRule], -- Rules from this module
253 mg_binds :: ![CoreBind], -- Bindings for this module
254 mg_foreign :: !ForeignStubs
257 -- The ModGuts takes on several slightly different forms:
259 -- After simplification, the following fields change slightly:
260 -- mg_rules Orphan rules only (local ones now attached to binds)
261 -- mg_binds With rules attached
263 -- After CoreTidy, the following fields change slightly:
264 -- mg_types Now contains Ids as well, replete with final IdInfo
265 -- The Ids are only the ones that are visible from
266 -- importing modules. Without -O that means only
267 -- exported Ids, but with -O importing modules may
268 -- see ids mentioned in unfoldings of exported Ids
270 -- mg_insts Same DFunIds as before, but with final IdInfo,
271 -- and the unique might have changed; remember that
272 -- CoreTidy links up the uniques of old and new versions
274 -- mg_rules All rules for exported things, substituted with final Ids
282 imp_direct :: ![(Module,Bool)], -- Explicitly-imported modules
283 -- Boolean is true if we imported the whole
284 -- module (apart, perhaps, from hiding some)
285 imp_pkg_mods :: !ModuleSet, -- Non-home-package modules on which we depend,
286 -- directly or indirectly
287 imp_home_names :: !NameSet -- Home package things on which we depend,
288 -- directly or indirectly
291 data ForeignStubs = NoStubs
293 SDoc -- Header file prototypes for
294 -- "foreign exported" functions
295 SDoc -- C stubs to use when calling
296 -- "foreign exported" functions
297 [FastString] -- Headers that need to be included
298 -- into C code generated for this module
299 [Id] -- Foreign-exported binders
300 -- we have to generate code to register these
303 data IfaceDecls = IfaceDecls { dcl_tycl :: [RenamedTyClDecl], -- Sorted
304 dcl_rules :: [RenamedRuleDecl], -- Sorted
305 dcl_insts :: [RenamedInstDecl] } -- Unsorted
307 mkIfaceDecls :: [RenamedTyClDecl] -> [RenamedRuleDecl] -> [RenamedInstDecl] -> IfaceDecls
308 mkIfaceDecls tycls rules insts
309 = IfaceDecls { dcl_tycl = sortLt lt_tycl tycls,
310 dcl_rules = sortLt lt_rule rules,
313 d1 `lt_tycl` d2 = tyClDeclName d1 < tyClDeclName d2
314 r1 `lt_rule` r2 = ifaceRuleDeclName r1 < ifaceRuleDeclName r2
318 emptyModIface :: Module -> ModIface
320 = ModIface { mi_module = mod,
321 mi_package = preludePackage, -- XXX fully bogus
322 mi_version = initialVersionInfo,
327 mi_fixities = emptyNameEnv,
328 mi_globals = Nothing,
329 mi_deprecs = NoDeprecs,
330 mi_decls = panic "emptyModIface: decls"
335 %************************************************************************
337 Parsed interface files
339 %************************************************************************
341 A ParsedIface is exactly as read from an interface file.
344 type IfaceDeprecs = Maybe (Either DeprecTxt [(RdrName,DeprecTxt)])
345 -- Nothing => NoDeprecs
346 -- Just (Left t) => DeprecAll
347 -- Just (Right p) => DeprecSome
351 pi_mod :: ModuleName,
352 pi_pkg :: PackageName,
353 pi_vers :: Version, -- Module version number
354 pi_orphan :: WhetherHasOrphans, -- Whether this module has orphans
355 pi_usages :: [ImportVersion OccName], -- Usages
356 pi_exports :: (Version, [RdrExportItem]), -- Exports
357 pi_decls :: [(Version, TyClDecl RdrName)], -- Local definitions
358 pi_fixity :: [FixitySig RdrName], -- Local fixity declarations,
359 pi_insts :: [InstDecl RdrName], -- Local instance declarations
360 pi_rules :: (Version, [RuleDecl RdrName]), -- Rules, with their version
361 pi_deprecs :: IfaceDeprecs -- Deprecations
366 %************************************************************************
368 \subsection{The interactive context}
370 %************************************************************************
373 data InteractiveContext
374 = InteractiveContext {
375 ic_toplev_scope :: [Module], -- Include the "top-level" scope of
378 ic_exports :: [Module], -- Include just the exports of these
381 ic_rn_gbl_env :: GlobalRdrEnv, -- The cached GlobalRdrEnv, built from
382 -- ic_toplev_scope and ic_exports
384 ic_rn_local_env :: LocalRdrEnv, -- Lexical context for variables bound
385 -- during interaction
387 ic_type_env :: TypeEnv -- Ditto for types
390 emptyInteractiveContext
391 = InteractiveContext { ic_toplev_scope = [],
393 ic_rn_gbl_env = emptyRdrEnv,
394 ic_rn_local_env = emptyRdrEnv,
395 ic_type_env = emptyTypeEnv }
397 icPrintUnqual :: InteractiveContext -> PrintUnqualified
398 icPrintUnqual ictxt = unQualInScope (ic_rn_gbl_env ictxt)
402 %************************************************************************
404 \subsection{Type environment stuff}
406 %************************************************************************
409 data TyThing = AnId Id
413 isTyClThing :: TyThing -> Bool
414 isTyClThing (ATyCon _) = True
415 isTyClThing (AClass _) = True
416 isTyClThing (AnId _) = False
418 instance NamedThing TyThing where
419 getName (AnId id) = getName id
420 getName (ATyCon tc) = getName tc
421 getName (AClass cl) = getName cl
423 instance Outputable TyThing where
424 ppr (AnId id) = ptext SLIT("AnId") <+> ppr id
425 ppr (ATyCon tc) = ptext SLIT("ATyCon") <+> ppr tc
426 ppr (AClass cl) = ptext SLIT("AClass") <+> ppr cl
429 typeEnvElts :: TypeEnv -> [TyThing]
430 typeEnvClasses :: TypeEnv -> [Class]
431 typeEnvTyCons :: TypeEnv -> [TyCon]
432 typeEnvIds :: TypeEnv -> [Id]
434 typeEnvElts env = nameEnvElts env
435 typeEnvClasses env = [cl | AClass cl <- typeEnvElts env]
436 typeEnvTyCons env = [tc | ATyCon tc <- typeEnvElts env]
437 typeEnvIds env = [id | AnId id <- typeEnvElts env]
439 implicitTyThingIds :: [TyThing] -> [Id]
440 -- Add the implicit data cons and selectors etc
441 implicitTyThingIds things
442 = concat (map go things)
445 go (AClass cl) = classSelIds cl
446 go (ATyCon tc) = tyConGenIds tc ++
448 [ n | dc <- tyConDataCons_maybe tc `orElse` [],
449 n <- implicitConIds tc dc]
450 -- Synonyms return empty list of constructors and selectors
452 implicitConIds tc dc -- Newtypes have a constructor wrapper,
454 | isNewTyCon tc = [dataConWrapId dc]
455 | otherwise = [dataConWorkId dc, dataConWrapId dc]
460 type TypeEnv = NameEnv TyThing
462 emptyTypeEnv = emptyNameEnv
464 mkTypeEnv :: [TyThing] -> TypeEnv
465 mkTypeEnv things = extendTypeEnvList emptyTypeEnv things
467 extendTypeEnvList :: TypeEnv -> [TyThing] -> TypeEnv
468 extendTypeEnvList env things
469 = extendNameEnvList env [(getName thing, thing) | thing <- things]
471 extendTypeEnvWithIds :: TypeEnv -> [Id] -> TypeEnv
472 extendTypeEnvWithIds env ids
473 = extendNameEnvList env [(getName id, AnId id) | id <- ids]
477 lookupType :: HomePackageTable -> PackageTypeEnv -> Name -> Maybe TyThing
478 lookupType hpt pte name
479 = case lookupModuleEnv hpt (nameModule name) of
480 Just details -> lookupNameEnv (md_types (hm_details details)) name
481 Nothing -> lookupNameEnv pte name
484 %************************************************************************
486 \subsection{Auxiliary types}
488 %************************************************************************
490 These types are defined here because they are mentioned in ModDetails,
491 but they are mostly elaborated elsewhere
496 vers_module :: Version, -- Changes when anything changes
497 vers_exports :: Version, -- Changes when export list changes
498 vers_rules :: Version, -- Changes when any rule changes
499 vers_decls :: NameEnv Version
500 -- Versions for "big" names only (not data constructors, class ops)
501 -- The version of an Id changes if its fixity changes
502 -- Ditto data constructors, class operations, except that the version of
503 -- the parent class/tycon changes
505 -- If a name isn't in the map, it means 'initialVersion'
508 initialVersionInfo :: VersionInfo
509 initialVersionInfo = VersionInfo { vers_module = initialVersion,
510 vers_exports = initialVersion,
511 vers_rules = initialVersion,
512 vers_decls = emptyNameEnv
515 lookupVersion :: NameEnv Version -> Name -> Version
516 lookupVersion env name = lookupNameEnv env name `orElse` initialVersion
518 data Deprecations = NoDeprecs
519 | DeprecAll DeprecTxt -- Whole module deprecated
520 | DeprecSome (NameEnv (Name,DeprecTxt)) -- Some things deprecated
522 -- We keep the Name in the range, so we can print them out
524 lookupDeprec :: Deprecations -> Name -> Maybe DeprecTxt
525 lookupDeprec NoDeprecs name = Nothing
526 lookupDeprec (DeprecAll txt) name = Just txt
527 lookupDeprec (DeprecSome env) name = case lookupNameEnv env name of
528 Just (_, txt) -> Just txt
531 plusDeprecs :: Deprecations -> Deprecations -> Deprecations
532 plusDeprecs d NoDeprecs = d
533 plusDeprecs NoDeprecs d = d
534 plusDeprecs d (DeprecAll t) = DeprecAll t
535 plusDeprecs (DeprecAll t) d = DeprecAll t
536 plusDeprecs (DeprecSome v1) (DeprecSome v2) = DeprecSome (v1 `plusNameEnv` v2)
538 instance Eq Deprecations where
539 -- Used when checking whether we need write a new interface
540 NoDeprecs == NoDeprecs = True
541 (DeprecAll t1) == (DeprecAll t2) = t1 == t2
542 (DeprecSome e1) == (DeprecSome e2) = nameEnvElts e1 == nameEnvElts e2
548 type Avails = [AvailInfo]
549 type AvailInfo = GenAvailInfo Name
550 type RdrAvailInfo = GenAvailInfo OccName
552 data GenAvailInfo name = Avail name -- An ordinary identifier
553 | AvailTC name -- The name of the type or class
554 [name] -- The available pieces of type/class.
555 -- NB: If the type or class is itself
556 -- to be in scope, it must be in this list.
557 -- Thus, typically: AvailTC Eq [Eq, ==, /=]
559 -- Equality used when deciding if the interface has changed
561 type RdrExportItem = (ModuleName, [RdrAvailInfo])
562 type ExportItem = (ModuleName, [AvailInfo])
564 availsToNameSet :: [AvailInfo] -> NameSet
565 availsToNameSet avails = foldl add emptyNameSet avails
567 add set avail = addListToNameSet set (availNames avail)
569 availName :: GenAvailInfo name -> name
570 availName (Avail n) = n
571 availName (AvailTC n _) = n
573 availNames :: GenAvailInfo name -> [name]
574 availNames (Avail n) = [n]
575 availNames (AvailTC n ns) = ns
577 instance Outputable n => Outputable (GenAvailInfo n) where
580 pprAvail :: Outputable n => GenAvailInfo n -> SDoc
581 pprAvail (AvailTC n ns) = ppr n <> case {- filter (/= n) -} ns of
583 ns' -> braces (hsep (punctuate comma (map ppr ns')))
585 pprAvail (Avail n) = ppr n
589 type FixityEnv = NameEnv (FixitySig Name)
590 -- We keep the whole fixity sig so that we
591 -- can report line-number info when there is a duplicate
592 -- fixity declaration
594 emptyFixityEnv :: FixityEnv
595 emptyFixityEnv = emptyNameEnv
597 lookupFixity :: FixityEnv -> Name -> Fixity
598 lookupFixity env n = case lookupNameEnv env n of
599 Just (FixitySig _ fix _) -> fix
600 Nothing -> defaultFixity
602 collectFixities :: FixityEnv -> [TyClDecl Name] -> [FixitySig Name]
603 -- Collect fixities for the specified declarations
604 collectFixities env decls
606 | d <- decls, (n,_) <- tyClDeclNames d,
607 Just fix <- [lookupNameEnv env n]
612 %************************************************************************
614 \subsection{WhatsImported}
616 %************************************************************************
619 type WhetherHasOrphans = Bool
621 -- * an instance decl in a module other than the defn module for
622 -- one of the tycons or classes in the instance head
623 -- * a transformation rule in a module other than the one defining
624 -- the function in the head of the rule.
626 type IsBootInterface = Bool
628 type ImportVersion name = (ModuleName, WhetherHasOrphans, IsBootInterface, WhatsImported name)
630 data WhatsImported name = NothingAtAll -- The module is below us in the
631 -- hierarchy, but we import nothing
632 -- Used for orphan modules, so they appear
635 | Everything Version -- Used for modules from other packages;
636 -- we record only the module's version number
639 Version -- Module version
640 (Maybe Version) -- Export-list version, if we depend on it
641 [(name,Version)] -- List guaranteed non-empty
642 Version -- Rules version
645 -- 'Specifically' doesn't let you say "I imported f but none of the rules in
646 -- the module". If you use anything in the module you get its rule version
647 -- So if the rules change, you'll recompile, even if you don't use them.
648 -- This is easy to implement, and it's safer: you might not have used the rules last
649 -- time round, but if someone has added a new rule you might need it this time
651 -- The export list field is (Just v) if we depend on the export list:
652 -- we imported the module without saying exactly what we imported
653 -- We need to recompile if the module exports changes, because we might
654 -- now have a name clash in the importing module.
658 %************************************************************************
660 \subsection{The persistent compiler state}
662 %************************************************************************
664 The @PersistentCompilerState@ persists across successive calls to the
668 data PersistentCompilerState
670 pcs_nc :: !NameCache,
671 pcs_EPS :: !ExternalPackageState
677 type PackageTypeEnv = TypeEnv
678 type PackageRuleBase = RuleBase
679 type PackageInstEnv = InstEnv
681 data ExternalPackageState
683 eps_PIT :: !PackageIfaceTable,
684 -- The ModuleIFaces for modules in external packages
685 -- whose interfaces we have opened
686 -- The declarations in these interface files are held in
687 -- eps_decls, eps_insts, eps_rules (below), not in the
688 -- mi_decls fields of the iPIT.
689 -- What _is_ in the iPIT is:
696 eps_imp_mods :: !ImportedModuleInfo,
697 -- Modules that we know something about, because they are mentioned
698 -- in interface files, BUT which we have not loaded yet.
699 -- No module is both in here and in the PIT
701 eps_PTE :: !PackageTypeEnv, -- Domain = external-package modules
703 eps_inst_env :: !PackageInstEnv, -- The total InstEnv accumulated from
704 -- all the external-package modules
705 eps_rule_base :: !PackageRuleBase, -- Ditto RuleEnv
708 -- Holding pens for stuff that has been read in from file,
709 -- but not yet slurped into the renamer
710 eps_decls :: !DeclsMap,
711 -- A single, global map of Names to unslurped decls
712 eps_insts :: !IfaceInsts,
713 -- The as-yet un-slurped instance decls; this bag is depleted when we
714 -- slurp an instance decl so that we don't slurp the same one twice.
715 -- Each is 'gated' by the names that must be available before
716 -- this instance decl is needed.
717 eps_rules :: !IfaceRules,
718 -- Similar to instance decls, only for rules
720 eps_inst_gates :: !NameSet -- Gates for instance decls
721 -- The instance gates must accumulate across
722 -- all invocations of the renamer;
723 -- see "the gating story" in RnIfaces.lhs
724 -- These names should all be from other packages;
725 -- for the home package we have all the instance
726 -- declarations anyhow
730 The NameCache makes sure that there is just one Unique assigned for
731 each original name; i.e. (module-name, occ-name) pair. The Name is
732 always stored as a Global, and has the SrcLoc of its binding location.
733 Actually that's not quite right. When we first encounter the original
734 name, we might not be at its binding site (e.g. we are reading an
735 interface file); so we give it 'noSrcLoc' then. Later, when we find
736 its binding site, we fix it up.
738 Exactly the same is true of the Module stored in the Name. When we first
739 encounter the occurrence, we may not know the details of the module, so
740 we just store junk. Then when we find the binding site, we fix it up.
744 = NameCache { nsUniqs :: UniqSupply,
746 nsNames :: OrigNameCache,
747 -- Ensures that one original name gets one unique
748 nsIPs :: OrigIParamCache
749 -- Ensures that one implicit parameter name gets one unique
752 type OrigNameCache = FiniteMap (ModuleName,OccName) Name
753 type OrigIParamCache = FiniteMap (IPName RdrName) (IPName Name)
756 @ImportedModuleInfo@ contains info ONLY about modules that have not yet
757 been loaded into the iPIT. These modules are mentioned in interfaces we've
758 already read, so we know a tiny bit about them, but we havn't yet looked
759 at the interface file for the module itself. It needs to persist across
760 invocations of the renamer, at least from Rename.checkOldIface to Rename.renameSource.
761 And there's no harm in it persisting across multiple compilations.
764 type ImportedModuleInfo
765 = FiniteMap ModuleName (WhetherHasOrphans, IsBootInterface)
768 A DeclsMap contains a binding for each Name in the declaration
769 including the constructors of a type decl etc. The Bool is True just
773 type DeclsMap = (NameEnv (AvailInfo, Bool, (Module, TyClDecl RdrName)), Int)
774 -- The Int says how many have been sucked in
776 type IfaceInsts = GatedDecls (InstDecl RdrName)
777 type IfaceRules = GatedDecls (RuleDecl RdrName)
779 type GatedDecls d = (Bag (GatedDecl d), Int) -- The Int says how many have been sucked in
780 type GatedDecl d = (GateFn, (Module, d))
781 type GateFn = (Name -> Bool) -> Bool -- Returns True <=> gate is open
782 -- The (Name -> Bool) fn returns True for visible Names
783 -- For example, suppose this is in an interface file
784 -- instance C T where ...
785 -- We want to slurp this decl if both C and T are "visible" in
786 -- the importing module. See "The gating story" in RnIfaces for details.
790 %************************************************************************
792 \subsection{Linkable stuff}
794 %************************************************************************
796 This stuff is in here, rather than (say) in Linker.lhs, because the Linker.lhs
797 stuff is the *dynamic* linker, and isn't present in a stage-1 compiler
801 linkableTime :: ClockTime, -- Time at which this linkable was built
802 -- (i.e. when the bytecodes were produced,
803 -- or the mod date on the files)
804 linkableModName :: ModuleName, -- Should be Module, but see below
805 linkableUnlinked :: [Unlinked]
808 isObjectLinkable :: Linkable -> Bool
809 isObjectLinkable l = all isObject (linkableUnlinked l)
811 instance Outputable Linkable where
812 ppr (LM when_made mod unlinkeds)
813 = (text "LinkableM" <+> parens (text (show when_made)) <+> ppr mod)
814 $$ nest 3 (ppr unlinkeds)
816 -------------------------------------------
821 | BCOs CompiledByteCode
824 data CompiledByteCode = NoByteCode
827 instance Outputable Unlinked where
828 ppr (DotO path) = text "DotO" <+> text path
829 ppr (DotA path) = text "DotA" <+> text path
830 ppr (DotDLL path) = text "DotDLL" <+> text path
832 ppr (BCOs bcos) = text "BCOs" <+> ppr bcos
834 ppr (BCOs bcos) = text "No byte code"
837 isObject (DotO _) = True
838 isObject (DotA _) = True
839 isObject (DotDLL _) = True
842 isInterpretable = not . isObject
844 nameOfObject (DotO fn) = fn
845 nameOfObject (DotA fn) = fn
846 nameOfObject (DotDLL fn) = fn
848 byteCodeOfObject (BCOs bc) = bc
852 %************************************************************************
854 \subsection{Provenance and export info}
856 %************************************************************************
858 A LocalRdrEnv is used for local bindings (let, where, lambda, case)
862 type LocalRdrEnv = RdrNameEnv Name
864 extendLocalRdrEnv :: LocalRdrEnv -> [Name] -> LocalRdrEnv
865 extendLocalRdrEnv env names
866 = addListToRdrEnv env [(mkRdrUnqual (nameOccName n), n) | n <- names]
869 The GlobalRdrEnv gives maps RdrNames to Names. There is a separate
870 one for each module, corresponding to that module's top-level scope.
873 type GlobalRdrEnv = RdrNameEnv [GlobalRdrElt]
874 -- The list is because there may be name clashes
875 -- These only get reported on lookup, not on construction
877 emptyGlobalRdrEnv = emptyRdrEnv
880 = GRE { gre_name :: Name,
881 gre_parent :: Name, -- Name of the "parent" structure
882 -- * the tycon of a data con
883 -- * the class of a class op
884 -- For others it's just the same as gre_name
885 gre_prov :: Provenance, -- Why it's in scope
886 gre_deprec :: Maybe DeprecTxt -- Whether this name is deprecated
889 instance Outputable GlobalRdrElt where
890 ppr gre = ppr (gre_name gre) <+>
891 parens (hsep [text "parent:" <+> ppr (gre_parent gre) <> comma,
892 pprNameProvenance gre])
894 = vcat (map pp (rdrEnvToList env))
896 pp (rn, gres) = ppr rn <> colon <+>
897 vcat [ ppr (gre_name gre) <+> pprNameProvenance gre
900 isLocalGRE :: GlobalRdrElt -> Bool
901 isLocalGRE (GRE {gre_prov = LocalDef}) = True
902 isLocalGRE other = False
905 @unQualInScope@ returns a function that takes a @Name@ and tells whether
906 its unqualified name is in scope. This is put as a boolean flag in
907 the @Name@'s provenance to guide whether or not to print the name qualified
911 unQualInScope :: GlobalRdrEnv -> Name -> Bool
912 -- True if 'f' is in scope, and has only one binding,
913 -- and the thing it is bound to is the name we are looking for
914 -- (i.e. false if A.f and B.f are both in scope as unqualified 'f')
916 -- Also checks for built-in syntax, which is always 'in scope'
918 -- This fn is only efficient if the shared
919 -- partial application is used a lot.
921 = \n -> n `elemNameSet` unqual_names || isBuiltInSyntaxName n
923 unqual_names :: NameSet
924 unqual_names = foldRdrEnv add emptyNameSet env
925 add rdr_name [gre] unquals | isUnqual rdr_name = addOneToNameSet unquals (gre_name gre)
926 add _ _ unquals = unquals
929 The "provenance" of something says how it came to be in scope.
933 = LocalDef -- Defined locally
935 | NonLocalDef -- Defined non-locally
938 -- Just used for grouping error messages (in RnEnv.warnUnusedBinds)
939 instance Eq Provenance where
940 p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False
942 instance Eq ImportReason where
943 p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False
945 instance Ord Provenance where
946 compare LocalDef LocalDef = EQ
947 compare LocalDef (NonLocalDef _) = LT
948 compare (NonLocalDef _) LocalDef = GT
950 compare (NonLocalDef reason1) (NonLocalDef reason2)
951 = compare reason1 reason2
953 instance Ord ImportReason where
954 compare ImplicitImport ImplicitImport = EQ
955 compare ImplicitImport (UserImport _ _ _) = LT
956 compare (UserImport _ _ _) ImplicitImport = GT
957 compare (UserImport m1 loc1 _) (UserImport m2 loc2 _)
958 = (m1 `compare` m2) `thenCmp` (loc1 `compare` loc2)
962 = UserImport Module SrcLoc Bool -- Imported from module M on line L
963 -- Note the M may well not be the defining module
965 -- The Bool is true iff the thing was named *explicitly* in the import spec,
966 -- rather than being imported as part of a group; e.g.
969 -- Here, everything imported by B, and the constructors of T
970 -- are not named explicitly; only T is named explicitly.
971 -- This info is used when warning of unused names.
973 | ImplicitImport -- Imported implicitly for some other reason
977 hasBetterProv :: Provenance -> Provenance -> Bool
979 -- a local thing over an imported thing
980 -- a user-imported thing over a non-user-imported thing
981 -- an explicitly-imported thing over an implicitly imported thing
982 hasBetterProv LocalDef _ = True
983 hasBetterProv (NonLocalDef (UserImport _ _ _ )) (NonLocalDef ImplicitImport) = True
984 hasBetterProv _ _ = False
986 pprNameProvenance :: GlobalRdrElt -> SDoc
987 pprNameProvenance (GRE {gre_name = name, gre_prov = prov})
989 LocalDef -> ptext SLIT("defined at") <+> ppr (nameSrcLoc name)
990 NonLocalDef why -> sep [ppr_reason why,
991 nest 2 (ppr_defn (nameSrcLoc name))]
993 ppr_reason ImplicitImport = ptext SLIT("implicitly imported")
994 ppr_reason (UserImport mod loc _) = ptext SLIT("imported from") <+> ppr mod <+> ptext SLIT("at") <+> ppr loc
996 ppr_defn loc | isGoodSrcLoc loc = parens (ptext SLIT("at") <+> ppr loc)