2 % (c) The University of Glasgow, 2000
4 \section[HscTypes]{Types for the per-module compiler}
10 ModDetails(..), ModIface(..),
11 HomeSymbolTable, PackageTypeEnv,
12 HomeIfaceTable, PackageIfaceTable, emptyIfaceTable,
13 lookupIface, lookupIfaceByModName,
16 IfaceDecls, mkIfaceDecls, dcl_tycl, dcl_rules, dcl_insts,
18 VersionInfo(..), initialVersionInfo,
20 TyThing(..), isTyClThing, implicitTyThingIds,
22 TypeEnv, lookupType, mkTypeEnv, extendTypeEnvList,
23 typeEnvClasses, typeEnvTyCons,
25 WhetherHasOrphans, ImportVersion, WhatsImported(..),
26 PersistentRenamerState(..), IsBootInterface, Avails, DeclsMap,
27 IfaceInsts, IfaceRules, GatedDecl, IsExported,
28 OrigNameEnv(..), OrigNameNameEnv, OrigNameIParamEnv,
29 AvailEnv, AvailInfo, GenAvailInfo(..),
30 PersistentCompilerState(..),
32 Deprecations(..), lookupDeprec,
34 InstEnv, ClsInstEnv, DFunId,
35 PackageInstEnv, PackageRuleBase,
37 GlobalRdrEnv, RdrAvailInfo, pprGlobalRdrEnv,
40 Provenance(..), ImportReason(..),
41 pprNameProvenance, hasBetterProv
45 #include "HsVersions.h"
47 import RdrName ( RdrNameEnv, emptyRdrEnv, rdrEnvToList )
48 import Name ( Name, NamedThing, getName, nameModule, nameSrcLoc )
50 import OccName ( OccName )
51 import Module ( Module, ModuleName, ModuleEnv,
52 lookupModuleEnv, lookupModuleEnvByName, emptyModuleEnv
54 import InstEnv ( InstEnv, ClsInstEnv, DFunId )
55 import Rules ( RuleBase )
57 import Class ( Class, classSelIds )
58 import TyCon ( TyCon, tyConGenIds, tyConSelIds, tyConDataConsIfAvailable )
59 import DataCon ( dataConId, dataConWrapId )
61 import BasicTypes ( Version, initialVersion, Fixity )
63 import HsSyn ( DeprecTxt, tyClDeclName, ifaceRuleDeclName )
64 import RdrHsSyn ( RdrNameInstDecl, RdrNameRuleDecl, RdrNameTyClDecl )
65 import RnHsSyn ( RenamedTyClDecl, RenamedRuleDecl, RenamedInstDecl )
67 import CoreSyn ( IdCoreRule )
69 import FiniteMap ( FiniteMap )
71 import Maybes ( seqMaybe )
73 import SrcLoc ( SrcLoc, isGoodSrcLoc )
74 import Util ( thenCmp, sortLt )
75 import UniqSupply ( UniqSupply )
78 %************************************************************************
80 \subsection{Module locations}
82 %************************************************************************
87 ml_hs_file :: Maybe FilePath,
88 ml_hspp_file :: Maybe FilePath, -- path of preprocessed source
89 ml_hi_file :: Maybe FilePath,
90 ml_obj_file :: Maybe FilePath
94 instance Outputable ModuleLocation where
98 For a module in another package, the hs_file and obj_file
99 components of ModuleLocation are undefined.
101 The locations specified by a ModuleLocation may or may not
102 correspond to actual files yet: for example, even if the object
103 file doesn't exist, the ModuleLocation still contains the path to
104 where the object file will reside if/when it is created.
107 %************************************************************************
109 \subsection{Symbol tables and Module details}
111 %************************************************************************
113 A @ModIface@ plus a @ModDetails@ summarises everything we know
114 about a compiled module. The @ModIface@ is the stuff *before* linking,
115 and can be written out to an interface file. The @ModDetails@ is after
116 linking; it is the "linked" form of the mi_decls field.
121 mi_module :: Module, -- Complete with package info
122 mi_version :: VersionInfo, -- Module version number
123 mi_orphan :: WhetherHasOrphans, -- Whether this module has orphans
124 mi_boot :: IsBootInterface, -- Whether this interface was read from an hi-boot file
126 mi_usages :: [ImportVersion Name], -- Usages; kept sorted so that it's easy
127 -- to decide whether to write a new iface file
128 -- (changing usages doesn't affect the version of
131 mi_exports :: [(ModuleName,Avails)], -- What it exports
132 -- Kept sorted by (mod,occ),
133 -- to make version comparisons easier
135 mi_globals :: GlobalRdrEnv, -- Its top level environment
137 mi_fixities :: NameEnv Fixity, -- Fixities
138 mi_deprecs :: Deprecations, -- Deprecations
140 mi_decls :: IfaceDecls -- The RnDecls form of ModDetails
143 data IfaceDecls = IfaceDecls { dcl_tycl :: [RenamedTyClDecl], -- Sorted
144 dcl_rules :: [RenamedRuleDecl], -- Sorted
145 dcl_insts :: [RenamedInstDecl] } -- Unsorted
147 mkIfaceDecls :: [RenamedTyClDecl] -> [RenamedRuleDecl] -> [RenamedInstDecl] -> IfaceDecls
148 mkIfaceDecls tycls rules insts
149 = IfaceDecls { dcl_tycl = sortLt lt_tycl tycls,
150 dcl_rules = sortLt lt_rule rules,
153 d1 `lt_tycl` d2 = nameOccName (tyClDeclName d1) < nameOccName (tyClDeclName d2)
154 r1 `lt_rule` r2 = nameOccName (ifaceRuleDeclName r1) < nameOccName (ifaceRuleDeclName r2)
156 -- I wanted to sort just by the Name, but there's a problem: we are comparing
157 -- the old version of an interface with the new version. The latter will use
158 -- local names like 'lvl23' that were constructed not by the renamer but by
159 -- the simplifier. So the unqiues aren't going to line up.
161 -- It's ok to compare by OccName because this comparison only drives the
162 -- computation of new version numbers.
164 -- Better solutions: Compare in a way that is insensitive to the name used
165 -- for local things. This would decrease the wobbles due
166 -- to 'lvl23' changing to 'lvl24'.
168 -- NB: there's a related comparision on MkIface.diffDecls!
173 -- typechecker should only look at this, not ModIface
174 -- Should be able to construct ModDetails from mi_decls in ModIface
177 -- The next three fields are created by the typechecker
179 md_insts :: [DFunId], -- Dfun-ids for the instances in this module
180 md_rules :: [IdCoreRule] -- Domain may include Ids from other modules
185 emptyModDetails :: ModDetails
187 = ModDetails { md_types = emptyTypeEnv,
192 emptyModIface :: Module -> ModIface
194 = ModIface { mi_module = mod,
195 mi_version = initialVersionInfo,
200 mi_fixities = emptyNameEnv,
201 mi_globals = emptyRdrEnv,
202 mi_deprecs = NoDeprecs,
203 mi_decls = panic "emptyModIface: decls"
207 Symbol tables map modules to ModDetails:
210 type SymbolTable = ModuleEnv ModDetails
211 type IfaceTable = ModuleEnv ModIface
213 type HomeIfaceTable = IfaceTable
214 type PackageIfaceTable = IfaceTable
216 type HomeSymbolTable = SymbolTable -- Domain = modules in the home package
218 emptyIfaceTable :: IfaceTable
219 emptyIfaceTable = emptyModuleEnv
222 Simple lookups in the symbol table.
225 lookupIface :: HomeIfaceTable -> PackageIfaceTable -> Name -> Maybe ModIface
226 -- We often have two IfaceTables, and want to do a lookup
227 lookupIface hit pit name
228 = lookupModuleEnv hit mod `seqMaybe` lookupModuleEnv pit mod
230 mod = nameModule name
232 lookupIfaceByModName :: HomeIfaceTable -> PackageIfaceTable -> ModuleName -> Maybe ModIface
233 -- We often have two IfaceTables, and want to do a lookup
234 lookupIfaceByModName hit pit mod
235 = lookupModuleEnvByName hit mod `seqMaybe` lookupModuleEnvByName pit mod
239 %************************************************************************
241 \subsection{Type environment stuff}
243 %************************************************************************
246 data TyThing = AnId Id
250 isTyClThing :: TyThing -> Bool
251 isTyClThing (ATyCon _) = True
252 isTyClThing (AClass _) = True
253 isTyClThing (AnId _) = False
255 instance NamedThing TyThing where
256 getName (AnId id) = getName id
257 getName (ATyCon tc) = getName tc
258 getName (AClass cl) = getName cl
260 instance Outputable TyThing where
261 ppr (AnId id) = ptext SLIT("AnId") <+> ppr id
262 ppr (ATyCon tc) = ptext SLIT("ATyCon") <+> ppr tc
263 ppr (AClass cl) = ptext SLIT("AClass") <+> ppr cl
265 typeEnvClasses env = [cl | AClass cl <- nameEnvElts env]
266 typeEnvTyCons env = [tc | ATyCon tc <- nameEnvElts env]
268 implicitTyThingIds :: [TyThing] -> [Id]
269 -- Add the implicit data cons and selectors etc
270 implicitTyThingIds things
271 = concat (map go things)
274 go (AClass cl) = classSelIds cl
275 go (ATyCon tc) = tyConGenIds tc ++
277 [ n | dc <- tyConDataConsIfAvailable tc,
278 n <- [dataConId dc, dataConWrapId dc] ]
279 -- Synonyms return empty list of constructors and selectors
284 type TypeEnv = NameEnv TyThing
286 emptyTypeEnv = emptyNameEnv
288 mkTypeEnv :: [TyThing] -> TypeEnv
289 mkTypeEnv things = extendTypeEnvList emptyTypeEnv things
291 extendTypeEnvList :: TypeEnv -> [TyThing] -> TypeEnv
292 extendTypeEnvList env things
293 = foldl add_thing env things
295 add_thing :: TypeEnv -> TyThing -> TypeEnv
296 add_thing env thing = extendNameEnv env (getName thing) thing
300 lookupType :: HomeSymbolTable -> PackageTypeEnv -> Name -> Maybe TyThing
301 lookupType hst pte name
302 = case lookupModuleEnv hst (nameModule name) of
303 Just details -> lookupNameEnv (md_types details) name
304 Nothing -> lookupNameEnv pte name
307 %************************************************************************
309 \subsection{Auxiliary types}
311 %************************************************************************
313 These types are defined here because they are mentioned in ModDetails,
314 but they are mostly elaborated elsewhere
319 vers_module :: Version, -- Changes when anything changes
320 vers_exports :: Version, -- Changes when export list changes
321 vers_rules :: Version, -- Changes when any rule changes
322 vers_decls :: NameEnv Version
323 -- Versions for "big" names only (not data constructors, class ops)
324 -- The version of an Id changes if its fixity changes
325 -- Ditto data constructors, class operations, except that the version of
326 -- the parent class/tycon changes
329 initialVersionInfo :: VersionInfo
330 initialVersionInfo = VersionInfo { vers_module = initialVersion,
331 vers_exports = initialVersion,
332 vers_rules = initialVersion,
333 vers_decls = emptyNameEnv }
335 data Deprecations = NoDeprecs
336 | DeprecAll DeprecTxt -- Whole module deprecated
337 | DeprecSome (NameEnv (Name,DeprecTxt)) -- Some things deprecated
339 -- We keep the Name in the range, so we can print them out
341 lookupDeprec :: Deprecations -> Name -> Maybe DeprecTxt
342 lookupDeprec NoDeprecs name = Nothing
343 lookupDeprec (DeprecAll txt) name = Just txt
344 lookupDeprec (DeprecSome env) name = case lookupNameEnv env name of
345 Just (_, txt) -> Just txt
351 type Avails = [AvailInfo]
352 type AvailInfo = GenAvailInfo Name
353 type RdrAvailInfo = GenAvailInfo OccName
355 data GenAvailInfo name = Avail name -- An ordinary identifier
356 | AvailTC name -- The name of the type or class
357 [name] -- The available pieces of type/class.
358 -- NB: If the type or class is itself
359 -- to be in scope, it must be in this list.
360 -- Thus, typically: AvailTC Eq [Eq, ==, /=]
362 -- Equality used when deciding if the interface has changed
364 type AvailEnv = NameEnv AvailInfo -- Maps a Name to the AvailInfo that contains it
366 instance Outputable n => Outputable (GenAvailInfo n) where
369 pprAvail :: Outputable n => GenAvailInfo n -> SDoc
370 pprAvail (AvailTC n ns) = ppr n <> case {- filter (/= n) -} ns of
372 ns' -> braces (hsep (punctuate comma (map ppr ns')))
374 pprAvail (Avail n) = ppr n
378 %************************************************************************
380 \subsection{ModIface}
382 %************************************************************************
385 type WhetherHasOrphans = Bool
387 -- * an instance decl in a module other than the defn module for
388 -- one of the tycons or classes in the instance head
389 -- * a transformation rule in a module other than the one defining
390 -- the function in the head of the rule.
392 type IsBootInterface = Bool
394 type ImportVersion name = (ModuleName, WhetherHasOrphans, IsBootInterface, WhatsImported name)
396 data WhatsImported name = NothingAtAll -- The module is below us in the
397 -- hierarchy, but we import nothing
399 | Everything Version -- Used for modules from other packages;
400 -- we record only the module's version number
403 Version -- Module version
404 (Maybe Version) -- Export-list version, if we depend on it
405 [(name,Version)] -- List guaranteed non-empty
406 Version -- Rules version
409 -- 'Specifically' doesn't let you say "I imported f but none of the rules in
410 -- the module". If you use anything in the module you get its rule version
411 -- So if the rules change, you'll recompile, even if you don't use them.
412 -- This is easy to implement, and it's safer: you might not have used the rules last
413 -- time round, but if someone has added a new rule you might need it this time
415 -- The export list field is (Just v) if we depend on the export list:
416 -- we imported the module without saying exactly what we imported
417 -- We need to recompile if the module exports changes, because we might
418 -- now have a name clash in the importing module.
420 type IsExported = Name -> Bool -- True for names that are exported from this module
424 %************************************************************************
426 \subsection{The persistent compiler state}
428 %************************************************************************
431 data PersistentCompilerState
433 pcs_PIT :: PackageIfaceTable, -- Domain = non-home-package modules
434 -- the mi_decls component is empty
436 pcs_PTE :: PackageTypeEnv, -- Domain = non-home-package modules
437 -- except that the InstEnv components is empty
439 pcs_insts :: PackageInstEnv, -- The total InstEnv accumulated from all
440 -- the non-home-package modules
442 pcs_rules :: PackageRuleBase, -- Ditto RuleEnv
444 pcs_PRS :: PersistentRenamerState
449 The @PersistentRenamerState@ persists across successive calls to the
453 * A name supply, which deals with allocating unique names to
454 (Module,OccName) original names,
456 * An accumulated TypeEnv from all the modules in imported packages
458 * An accumulated InstEnv from all the modules in imported packages
459 The point is that we don't want to keep recreating it whenever
460 we compile a new module. The InstEnv component of pcPST is empty.
461 (This means we might "see" instances that we shouldn't "really" see;
462 but the Haskell Report is vague on what is meant to be visible,
463 so we just take the easy road here.)
467 * A "holding pen" for declarations that have been read out of
468 interface files but not yet sucked in, renamed, and typechecked
471 type PackageTypeEnv = TypeEnv
472 type PackageRuleBase = RuleBase
473 type PackageInstEnv = InstEnv
475 data PersistentRenamerState
476 = PRS { prsOrig :: OrigNameEnv,
477 prsDecls :: DeclsMap,
478 prsInsts :: IfaceInsts,
479 prsRules :: IfaceRules,
484 The OrigNameEnv makes sure that there is just one Unique assigned for
485 each original name; i.e. (module-name, occ-name) pair. The Name is
486 always stored as a Global, and has the SrcLoc of its binding location.
487 Actually that's not quite right. When we first encounter the original
488 name, we might not be at its binding site (e.g. we are reading an
489 interface file); so we give it 'noSrcLoc' then. Later, when we find
490 its binding site, we fix it up.
492 Exactly the same is true of the Module stored in the Name. When we first
493 encounter the occurrence, we may not know the details of the module, so
494 we just store junk. Then when we find the binding site, we fix it up.
498 = Orig { origNames :: OrigNameNameEnv,
499 -- Ensures that one original name gets one unique
500 origIParam :: OrigNameIParamEnv
501 -- Ensures that one implicit parameter name gets one unique
504 type OrigNameNameEnv = FiniteMap (ModuleName,OccName) Name
505 type OrigNameIParamEnv = FiniteMap OccName Name
509 A DeclsMap contains a binding for each Name in the declaration
510 including the constructors of a type decl etc. The Bool is True just
514 type DeclsMap = (NameEnv (AvailInfo, Bool, (Module, RdrNameTyClDecl)), Int)
515 -- The Int says how many have been sucked in
517 type IfaceInsts = GatedDecls RdrNameInstDecl
518 type IfaceRules = GatedDecls RdrNameRuleDecl
520 type GatedDecls d = (Bag (GatedDecl d), Int) -- The Int says how many have been sucked in
521 type GatedDecl d = ([Name], (Module, d))
525 %************************************************************************
527 \subsection{Provenance and export info}
529 %************************************************************************
531 The GlobalRdrEnv gives maps RdrNames to Names. There is a separate
532 one for each module, corresponding to that module's top-level scope.
535 type GlobalRdrEnv = RdrNameEnv [(Name,Provenance)] -- The list is because there may be name clashes
536 -- These only get reported on lookup,
537 -- not on construction
540 = vcat (map pp (rdrEnvToList env))
542 pp (rn, nps) = ppr rn <> colon <+>
543 vcat [ppr n <+> pprNameProvenance n p | (n,p) <- nps]
546 The "provenance" of something says how it came to be in scope.
550 = LocalDef -- Defined locally
552 | NonLocalDef -- Defined non-locally
555 -- Just used for grouping error messages (in RnEnv.warnUnusedBinds)
556 instance Eq Provenance where
557 p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False
559 instance Eq ImportReason where
560 p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False
562 instance Ord Provenance where
563 compare LocalDef LocalDef = EQ
564 compare LocalDef (NonLocalDef _) = LT
565 compare (NonLocalDef _) LocalDef = GT
567 compare (NonLocalDef reason1) (NonLocalDef reason2)
568 = compare reason1 reason2
570 instance Ord ImportReason where
571 compare ImplicitImport ImplicitImport = EQ
572 compare ImplicitImport (UserImport _ _ _) = LT
573 compare (UserImport _ _ _) ImplicitImport = GT
574 compare (UserImport m1 loc1 _) (UserImport m2 loc2 _)
575 = (m1 `compare` m2) `thenCmp` (loc1 `compare` loc2)
579 = UserImport Module SrcLoc Bool -- Imported from module M on line L
580 -- Note the M may well not be the defining module
582 -- The Bool is true iff the thing was named *explicitly* in the import spec,
583 -- rather than being imported as part of a group; e.g.
586 -- Here, everything imported by B, and the constructors of T
587 -- are not named explicitly; only T is named explicitly.
588 -- This info is used when warning of unused names.
590 | ImplicitImport -- Imported implicitly for some other reason
594 hasBetterProv :: Provenance -> Provenance -> Bool
596 -- a local thing over an imported thing
597 -- a user-imported thing over a non-user-imported thing
598 -- an explicitly-imported thing over an implicitly imported thing
599 hasBetterProv LocalDef _ = True
600 hasBetterProv (NonLocalDef (UserImport _ _ _ )) (NonLocalDef ImplicitImport) = True
601 hasBetterProv _ _ = False
603 pprNameProvenance :: Name -> Provenance -> SDoc
604 pprNameProvenance name LocalDef = ptext SLIT("defined at") <+> ppr (nameSrcLoc name)
605 pprNameProvenance name (NonLocalDef why) = sep [ppr_reason why,
606 nest 2 (parens (ppr_defn (nameSrcLoc name)))]
608 ppr_reason ImplicitImport = ptext SLIT("implicitly imported")
609 ppr_reason (UserImport mod loc _) = ptext SLIT("imported from") <+> ppr mod <+> ptext SLIT("at") <+> ppr loc
611 ppr_defn loc | isGoodSrcLoc loc = ptext SLIT("at") <+> ppr loc