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,
18 VersionInfo(..), initialVersionInfo,
20 TyThing(..), isTyClThing,
22 TypeEnv, lookupType, mkTypeEnv, extendTypeEnvList,
23 typeEnvClasses, typeEnvTyCons,
25 WhetherHasOrphans, ImportVersion, WhatsImported(..),
26 PersistentRenamerState(..), IsBootInterface, Avails, DeclsMap,
27 IfaceInsts, IfaceRules, GatedDecl,
28 OrigNameEnv(..), OrigNameNameEnv, OrigNameIParamEnv,
29 AvailEnv, AvailInfo, GenAvailInfo(..),
30 PersistentCompilerState(..),
32 Deprecations(..), lookupDeprec,
34 InstEnv, ClsInstEnv, DFunId,
35 PackageInstEnv, PackageRuleBase,
37 GlobalRdrEnv, RdrAvailInfo,
40 Provenance(..), ImportReason(..), PrintUnqualified,
41 pprNameProvenance, hasBetterProv
45 #include "HsVersions.h"
47 import RdrName ( RdrNameEnv, emptyRdrEnv )
48 import Name ( Name, NamedThing, isLocallyDefined,
49 getName, nameModule, nameSrcLoc )
51 import NameSet ( NameSet )
52 import OccName ( OccName )
53 import Module ( Module, ModuleName, ModuleEnv,
54 lookupModuleEnv, lookupModuleEnvByName, emptyModuleEnv
56 import InstEnv ( InstEnv, ClsInstEnv, DFunId )
57 import Rules ( RuleBase )
59 import Class ( Class )
60 import TyCon ( TyCon )
62 import BasicTypes ( Version, initialVersion, Fixity )
64 import HsSyn ( DeprecTxt )
65 import RdrHsSyn ( RdrNameHsDecl, RdrNameTyClDecl )
66 import RnHsSyn ( RenamedTyClDecl, RenamedRuleDecl, RenamedInstDecl )
68 import CoreSyn ( IdCoreRule )
70 import FiniteMap ( FiniteMap )
72 import Maybes ( seqMaybe )
74 import SrcLoc ( SrcLoc, isGoodSrcLoc )
75 import Util ( thenCmp )
76 import UniqSupply ( UniqSupply )
79 %************************************************************************
81 \subsection{Module locations}
83 %************************************************************************
88 ml_hs_file :: Maybe FilePath,
89 ml_hspp_file :: Maybe FilePath, -- path of preprocessed source
90 ml_hi_file :: Maybe FilePath,
91 ml_obj_file :: Maybe FilePath
95 instance Outputable ModuleLocation where
99 For a module in another package, the hs_file and obj_file
100 components of ModuleLocation are undefined.
102 The locations specified by a ModuleLocation may or may not
103 correspond to actual files yet: for example, even if the object
104 file doesn't exist, the ModuleLocation still contains the path to
105 where the object file will reside if/when it is created.
108 %************************************************************************
110 \subsection{Symbol tables and Module details}
112 %************************************************************************
114 A @ModIface@ plus a @ModDetails@ summarises everything we know
115 about a compiled module. The @ModIface@ is the stuff *before* linking,
116 and can be written out to an interface file. The @ModDetails@ is after
117 linking; it is the "linked" form of the mi_decls field.
122 mi_module :: Module, -- Complete with package info
123 mi_version :: VersionInfo, -- Module version number
124 mi_orphan :: WhetherHasOrphans, -- Whether this module has orphans
125 mi_boot :: IsBootInterface, -- Whether this interface was read from an hi-boot file
127 mi_usages :: [ImportVersion Name], -- Usages; kept sorted so that it's easy
128 -- to decide whether to write a new iface file
129 -- (changing usages doesn't affect the version of
132 mi_exports :: [(ModuleName,Avails)], -- What it exports
133 -- Kept sorted by (mod,occ),
134 -- to make version comparisons easier
136 mi_globals :: GlobalRdrEnv, -- Its top level environment
138 mi_fixities :: NameEnv Fixity, -- Fixities
139 mi_deprecs :: Deprecations, -- Deprecations
141 mi_decls :: IfaceDecls -- The RnDecls form of ModDetails
144 data IfaceDecls = IfaceDecls { dcl_tycl :: [RenamedTyClDecl], -- Sorted
145 dcl_rules :: [RenamedRuleDecl], -- Sorted
146 dcl_insts :: [RenamedInstDecl] } -- Unsorted
148 -- typechecker should only look at this, not ModIface
149 -- Should be able to construct ModDetails from mi_decls in ModIface
152 -- The next three fields are created by the typechecker
154 md_insts :: [DFunId], -- Dfun-ids for the instances in this module
155 md_rules :: [IdCoreRule] -- Domain may include Ids from other modules
160 emptyModDetails :: ModDetails
162 = ModDetails { md_types = emptyTypeEnv,
167 emptyModIface :: Module -> ModIface
169 = ModIface { mi_module = mod,
170 mi_version = initialVersionInfo,
175 mi_fixities = emptyNameEnv,
176 mi_globals = emptyRdrEnv,
177 mi_deprecs = NoDeprecs,
178 mi_decls = panic "emptyModIface: decls"
182 Symbol tables map modules to ModDetails:
185 type SymbolTable = ModuleEnv ModDetails
186 type IfaceTable = ModuleEnv ModIface
188 type HomeIfaceTable = IfaceTable
189 type PackageIfaceTable = IfaceTable
191 type HomeSymbolTable = SymbolTable -- Domain = modules in the home package
193 emptyIfaceTable :: IfaceTable
194 emptyIfaceTable = emptyModuleEnv
197 Simple lookups in the symbol table.
200 lookupIface :: HomeIfaceTable -> PackageIfaceTable
201 -> Module -> Name -- The module is to use for locally-defined names
203 -- We often have two IfaceTables, and want to do a lookup
204 lookupIface hit pit this_mod name
205 | isLocallyDefined name = lookupModuleEnv hit this_mod
206 | otherwise = lookupModuleEnv hit mod `seqMaybe` lookupModuleEnv pit mod
208 mod = nameModule name
210 lookupIfaceByModName :: ModuleEnv a -> ModuleEnv a -> ModuleName -> Maybe a
211 -- We often have two Symbol- or IfaceTables, and want to do a lookup
212 lookupIfaceByModName ht pt mod
213 = lookupModuleEnvByName ht mod `seqMaybe` lookupModuleEnvByName pt mod
217 %************************************************************************
219 \subsection{Type environment stuff}
221 %************************************************************************
224 data TyThing = AnId Id
228 isTyClThing :: TyThing -> Bool
229 isTyClThing (ATyCon _) = True
230 isTyClThing (AClass _) = True
231 isTyClThing (AnId _) = False
233 instance NamedThing TyThing where
234 getName (AnId id) = getName id
235 getName (ATyCon tc) = getName tc
236 getName (AClass cl) = getName cl
238 typeEnvClasses env = [cl | AClass cl <- nameEnvElts env]
239 typeEnvTyCons env = [tc | ATyCon tc <- nameEnvElts env]
245 type TypeEnv = NameEnv TyThing
247 emptyTypeEnv = emptyNameEnv
249 mkTypeEnv :: [TyThing] -> TypeEnv
250 mkTypeEnv things = extendTypeEnvList emptyTypeEnv things
252 extendTypeEnvList :: TypeEnv -> [TyThing] -> TypeEnv
253 extendTypeEnvList env things
254 = foldl add_thing env things
256 add_thing :: TypeEnv -> TyThing -> TypeEnv
257 add_thing env thing = extendNameEnv env (getName thing) thing
261 lookupType :: HomeSymbolTable -> PackageTypeEnv -> Name -> Maybe TyThing
262 lookupType hst pte name
263 = ASSERT2( not (isLocallyDefined name), ppr name )
264 case lookupModuleEnv hst (nameModule name) of
265 Just details -> lookupNameEnv (md_types details) name
266 Nothing -> lookupNameEnv pte name
269 %************************************************************************
271 \subsection{Auxiliary types}
273 %************************************************************************
275 These types are defined here because they are mentioned in ModDetails,
276 but they are mostly elaborated elsewhere
281 vers_module :: Version, -- Changes when anything changes
282 vers_exports :: Version, -- Changes when export list changes
283 vers_rules :: Version, -- Changes when any rule changes
284 vers_decls :: NameEnv Version
285 -- Versions for "big" names only (not data constructors, class ops)
286 -- The version of an Id changes if its fixity changes
287 -- Ditto data constructors, class operations, except that the version of
288 -- the parent class/tycon changes
291 initialVersionInfo :: VersionInfo
292 initialVersionInfo = VersionInfo { vers_module = initialVersion,
293 vers_exports = initialVersion,
294 vers_rules = initialVersion,
295 vers_decls = emptyNameEnv }
297 data Deprecations = NoDeprecs
298 | DeprecAll DeprecTxt -- Whole module deprecated
299 | DeprecSome (NameEnv (Name,DeprecTxt)) -- Some things deprecated
301 -- We keep the Name in the range, so we can print them out
303 lookupDeprec :: Deprecations -> Name -> Maybe DeprecTxt
304 lookupDeprec NoDeprecs name = Nothing
305 lookupDeprec (DeprecAll txt) name = Just txt
306 lookupDeprec (DeprecSome env) name = case lookupNameEnv env name of
307 Just (_, txt) -> Just txt
313 type Avails = [AvailInfo]
314 type AvailInfo = GenAvailInfo Name
315 type RdrAvailInfo = GenAvailInfo OccName
317 data GenAvailInfo name = Avail name -- An ordinary identifier
318 | AvailTC name -- The name of the type or class
319 [name] -- The available pieces of type/class.
320 -- NB: If the type or class is itself
321 -- to be in scope, it must be in this list.
322 -- Thus, typically: AvailTC Eq [Eq, ==, /=]
324 -- Equality used when deciding if the interface has changed
326 type AvailEnv = NameEnv AvailInfo -- Maps a Name to the AvailInfo that contains it
328 instance Outputable n => Outputable (GenAvailInfo n) where
331 pprAvail :: Outputable n => GenAvailInfo n -> SDoc
332 pprAvail (AvailTC n ns) = ppr n <> case {- filter (/= n) -} ns of
334 ns' -> braces (hsep (punctuate comma (map ppr ns')))
336 pprAvail (Avail n) = ppr n
340 %************************************************************************
342 \subsection{ModIface}
344 %************************************************************************
347 type WhetherHasOrphans = Bool
349 -- * an instance decl in a module other than the defn module for
350 -- one of the tycons or classes in the instance head
351 -- * a transformation rule in a module other than the one defining
352 -- the function in the head of the rule.
354 type IsBootInterface = Bool
356 type ImportVersion name = (ModuleName, WhetherHasOrphans, IsBootInterface, WhatsImported name)
358 data WhatsImported name = NothingAtAll -- The module is below us in the
359 -- hierarchy, but we import nothing
361 | Everything Version -- Used for modules from other packages;
362 -- we record only the module's version number
365 Version -- Module version
366 (Maybe Version) -- Export-list version, if we depend on it
367 [(name,Version)] -- List guaranteed non-empty
368 Version -- Rules version
371 -- 'Specifically' doesn't let you say "I imported f but none of the rules in
372 -- the module". If you use anything in the module you get its rule version
373 -- So if the rules change, you'll recompile, even if you don't use them.
374 -- This is easy to implement, and it's safer: you might not have used the rules last
375 -- time round, but if someone has added a new rule you might need it this time
377 -- The export list field is (Just v) if we depend on the export list:
378 -- we imported the module without saying exactly what we imported
379 -- We need to recompile if the module exports changes, because we might
380 -- now have a name clash in the importing module.
384 %************************************************************************
386 \subsection{The persistent compiler state}
388 %************************************************************************
391 data PersistentCompilerState
393 pcs_PIT :: PackageIfaceTable, -- Domain = non-home-package modules
394 -- the mi_decls component is empty
396 pcs_PTE :: PackageTypeEnv, -- Domain = non-home-package modules
397 -- except that the InstEnv components is empty
399 pcs_insts :: PackageInstEnv, -- The total InstEnv accumulated from all
400 -- the non-home-package modules
402 pcs_rules :: PackageRuleBase, -- Ditto RuleEnv
404 pcs_PRS :: PersistentRenamerState
409 The @PersistentRenamerState@ persists across successive calls to the
413 * A name supply, which deals with allocating unique names to
414 (Module,OccName) original names,
416 * An accumulated TypeEnv from all the modules in imported packages
418 * An accumulated InstEnv from all the modules in imported packages
419 The point is that we don't want to keep recreating it whenever
420 we compile a new module. The InstEnv component of pcPST is empty.
421 (This means we might "see" instances that we shouldn't "really" see;
422 but the Haskell Report is vague on what is meant to be visible,
423 so we just take the easy road here.)
427 * A "holding pen" for declarations that have been read out of
428 interface files but not yet sucked in, renamed, and typechecked
431 type PackageTypeEnv = TypeEnv
432 type PackageRuleBase = RuleBase
433 type PackageInstEnv = InstEnv
435 data PersistentRenamerState
436 = PRS { prsOrig :: OrigNameEnv,
437 prsDecls :: DeclsMap,
438 prsInsts :: IfaceInsts,
439 prsRules :: IfaceRules,
444 The OrigNameEnv makes sure that there is just one Unique assigned for
445 each original name; i.e. (module-name, occ-name) pair. The Name is
446 always stored as a Global, and has the SrcLoc of its binding location.
447 Actually that's not quite right. When we first encounter the original
448 name, we might not be at its binding site (e.g. we are reading an
449 interface file); so we give it 'noSrcLoc' then. Later, when we find
450 its binding site, we fix it up.
452 Exactly the same is true of the Module stored in the Name. When we first
453 encounter the occurrence, we may not know the details of the module, so
454 we just store junk. Then when we find the binding site, we fix it up.
458 = Orig { origNames :: OrigNameNameEnv,
459 -- Ensures that one original name gets one unique
460 origIParam :: OrigNameIParamEnv
461 -- Ensures that one implicit parameter name gets one unique
464 type OrigNameNameEnv = FiniteMap (ModuleName,OccName) Name
465 type OrigNameIParamEnv = FiniteMap OccName Name
469 A DeclsMap contains a binding for each Name in the declaration
470 including the constructors of a type decl etc. The Bool is True just
474 type DeclsMap = NameEnv (AvailInfo, Bool, (Module, RdrNameTyClDecl))
476 type IfaceInsts = Bag GatedDecl
477 type IfaceRules = Bag GatedDecl
479 type GatedDecl = ([Name], (Module, RdrNameHsDecl))
483 %************************************************************************
485 \subsection{Provenance and export info}
487 %************************************************************************
489 The GlobalRdrEnv gives maps RdrNames to Names. There is a separate
490 one for each module, corresponding to that module's top-level scope.
493 type GlobalRdrEnv = RdrNameEnv [(Name,Provenance)] -- The list is because there may be name clashes
494 -- These only get reported on lookup,
495 -- not on construction
498 The "provenance" of something says how it came to be in scope.
502 = LocalDef -- Defined locally
504 | NonLocalDef -- Defined non-locally
508 -- Just used for grouping error messages (in RnEnv.warnUnusedBinds)
509 instance Eq Provenance where
510 p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False
512 instance Eq ImportReason where
513 p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False
515 instance Ord Provenance where
516 compare LocalDef LocalDef = EQ
517 compare LocalDef (NonLocalDef _ _) = LT
518 compare (NonLocalDef _ _) LocalDef = GT
520 compare (NonLocalDef reason1 _) (NonLocalDef reason2 _)
521 = compare reason1 reason2
523 instance Ord ImportReason where
524 compare ImplicitImport ImplicitImport = EQ
525 compare ImplicitImport (UserImport _ _ _) = LT
526 compare (UserImport _ _ _) ImplicitImport = GT
527 compare (UserImport m1 loc1 _) (UserImport m2 loc2 _)
528 = (m1 `compare` m2) `thenCmp` (loc1 `compare` loc2)
532 = UserImport Module SrcLoc Bool -- Imported from module M on line L
533 -- Note the M may well not be the defining module
535 -- The Bool is true iff the thing was named *explicitly* in the import spec,
536 -- rather than being imported as part of a group; e.g.
539 -- Here, everything imported by B, and the constructors of T
540 -- are not named explicitly; only T is named explicitly.
541 -- This info is used when warning of unused names.
543 | ImplicitImport -- Imported implicitly for some other reason
546 type PrintUnqualified = Bool -- True <=> the unqualified name of this thing is
547 -- in scope in this module, so print it
548 -- unqualified in error messages
552 hasBetterProv :: Provenance -> Provenance -> Bool
554 -- a local thing over an imported thing
555 -- a user-imported thing over a non-user-imported thing
556 -- an explicitly-imported thing over an implicitly imported thing
557 hasBetterProv LocalDef _ = True
558 hasBetterProv (NonLocalDef (UserImport _ _ True) _) _ = True
559 hasBetterProv (NonLocalDef (UserImport _ _ _ ) _) (NonLocalDef ImplicitImport _) = True
560 hasBetterProv _ _ = False
562 pprNameProvenance :: Name -> Provenance -> SDoc
563 pprNameProvenance name LocalDef = ptext SLIT("defined at") <+> ppr (nameSrcLoc name)
564 pprNameProvenance name (NonLocalDef why _) = sep [ppr_reason why,
565 nest 2 (parens (ppr_defn (nameSrcLoc name)))]
567 ppr_reason ImplicitImport = ptext SLIT("implicitly imported")
568 ppr_reason (UserImport mod loc _) = ptext SLIT("imported from") <+> ppr mod <+> ptext SLIT("at") <+> ppr loc
570 ppr_defn loc | isGoodSrcLoc loc = ptext SLIT("at") <+> ppr loc