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 OccName ( OccName )
52 import Module ( Module, ModuleName, ModuleEnv,
53 lookupModuleEnv, lookupModuleEnvByName, emptyModuleEnv
55 import InstEnv ( InstEnv, ClsInstEnv, DFunId )
56 import Rules ( RuleBase )
58 import Class ( Class )
59 import TyCon ( TyCon )
61 import BasicTypes ( Version, initialVersion, Fixity )
63 import HsSyn ( DeprecTxt )
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 )
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 -- typechecker should only look at this, not ModIface
148 -- Should be able to construct ModDetails from mi_decls in ModIface
151 -- The next three fields are created by the typechecker
153 md_insts :: [DFunId], -- Dfun-ids for the instances in this module
154 md_rules :: [IdCoreRule] -- Domain may include Ids from other modules
159 emptyModDetails :: ModDetails
161 = ModDetails { md_types = emptyTypeEnv,
166 emptyModIface :: Module -> ModIface
168 = ModIface { mi_module = mod,
169 mi_version = initialVersionInfo,
174 mi_fixities = emptyNameEnv,
175 mi_globals = emptyRdrEnv,
176 mi_deprecs = NoDeprecs,
177 mi_decls = panic "emptyModIface: decls"
181 Symbol tables map modules to ModDetails:
184 type SymbolTable = ModuleEnv ModDetails
185 type IfaceTable = ModuleEnv ModIface
187 type HomeIfaceTable = IfaceTable
188 type PackageIfaceTable = IfaceTable
190 type HomeSymbolTable = SymbolTable -- Domain = modules in the home package
192 emptyIfaceTable :: IfaceTable
193 emptyIfaceTable = emptyModuleEnv
196 Simple lookups in the symbol table.
199 lookupIface :: HomeIfaceTable -> PackageIfaceTable
200 -> Module -> Name -- The module is to use for locally-defined names
202 -- We often have two IfaceTables, and want to do a lookup
203 lookupIface hit pit this_mod name
204 | isLocallyDefined name = lookupModuleEnv hit this_mod
205 | otherwise = lookupModuleEnv hit mod `seqMaybe` lookupModuleEnv pit mod
207 mod = nameModule name
209 lookupIfaceByModName :: ModuleEnv a -> ModuleEnv a -> ModuleName -> Maybe a
210 -- We often have two Symbol- or IfaceTables, and want to do a lookup
211 lookupIfaceByModName ht pt mod
212 = lookupModuleEnvByName ht mod `seqMaybe` lookupModuleEnvByName pt mod
216 %************************************************************************
218 \subsection{Type environment stuff}
220 %************************************************************************
223 data TyThing = AnId Id
227 isTyClThing :: TyThing -> Bool
228 isTyClThing (ATyCon _) = True
229 isTyClThing (AClass _) = True
230 isTyClThing (AnId _) = False
232 instance NamedThing TyThing where
233 getName (AnId id) = getName id
234 getName (ATyCon tc) = getName tc
235 getName (AClass cl) = getName cl
237 typeEnvClasses env = [cl | AClass cl <- nameEnvElts env]
238 typeEnvTyCons env = [tc | ATyCon tc <- nameEnvElts env]
244 type TypeEnv = NameEnv TyThing
246 emptyTypeEnv = emptyNameEnv
248 mkTypeEnv :: [TyThing] -> TypeEnv
249 mkTypeEnv things = extendTypeEnvList emptyTypeEnv things
251 extendTypeEnvList :: TypeEnv -> [TyThing] -> TypeEnv
252 extendTypeEnvList env things
253 = foldl add_thing env things
255 add_thing :: TypeEnv -> TyThing -> TypeEnv
256 add_thing env thing = extendNameEnv env (getName thing) thing
260 lookupType :: HomeSymbolTable -> PackageTypeEnv -> Name -> Maybe TyThing
261 lookupType hst pte name
262 = ASSERT2( not (isLocallyDefined name), ppr name )
263 case lookupModuleEnv hst (nameModule name) of
264 Just details -> lookupNameEnv (md_types details) name
265 Nothing -> lookupNameEnv pte name
268 %************************************************************************
270 \subsection{Auxiliary types}
272 %************************************************************************
274 These types are defined here because they are mentioned in ModDetails,
275 but they are mostly elaborated elsewhere
280 vers_module :: Version, -- Changes when anything changes
281 vers_exports :: Version, -- Changes when export list changes
282 vers_rules :: Version, -- Changes when any rule changes
283 vers_decls :: NameEnv Version
284 -- Versions for "big" names only (not data constructors, class ops)
285 -- The version of an Id changes if its fixity changes
286 -- Ditto data constructors, class operations, except that the version of
287 -- the parent class/tycon changes
290 initialVersionInfo :: VersionInfo
291 initialVersionInfo = VersionInfo { vers_module = initialVersion,
292 vers_exports = initialVersion,
293 vers_rules = initialVersion,
294 vers_decls = emptyNameEnv }
296 data Deprecations = NoDeprecs
297 | DeprecAll DeprecTxt -- Whole module deprecated
298 | DeprecSome (NameEnv (Name,DeprecTxt)) -- Some things deprecated
300 -- We keep the Name in the range, so we can print them out
302 lookupDeprec :: Deprecations -> Name -> Maybe DeprecTxt
303 lookupDeprec NoDeprecs name = Nothing
304 lookupDeprec (DeprecAll txt) name = Just txt
305 lookupDeprec (DeprecSome env) name = case lookupNameEnv env name of
306 Just (_, txt) -> Just txt
312 type Avails = [AvailInfo]
313 type AvailInfo = GenAvailInfo Name
314 type RdrAvailInfo = GenAvailInfo OccName
316 data GenAvailInfo name = Avail name -- An ordinary identifier
317 | AvailTC name -- The name of the type or class
318 [name] -- The available pieces of type/class.
319 -- NB: If the type or class is itself
320 -- to be in scope, it must be in this list.
321 -- Thus, typically: AvailTC Eq [Eq, ==, /=]
323 -- Equality used when deciding if the interface has changed
325 type AvailEnv = NameEnv AvailInfo -- Maps a Name to the AvailInfo that contains it
327 instance Outputable n => Outputable (GenAvailInfo n) where
330 pprAvail :: Outputable n => GenAvailInfo n -> SDoc
331 pprAvail (AvailTC n ns) = ppr n <> case {- filter (/= n) -} ns of
333 ns' -> braces (hsep (punctuate comma (map ppr ns')))
335 pprAvail (Avail n) = ppr n
339 %************************************************************************
341 \subsection{ModIface}
343 %************************************************************************
346 type WhetherHasOrphans = Bool
348 -- * an instance decl in a module other than the defn module for
349 -- one of the tycons or classes in the instance head
350 -- * a transformation rule in a module other than the one defining
351 -- the function in the head of the rule.
353 type IsBootInterface = Bool
355 type ImportVersion name = (ModuleName, WhetherHasOrphans, IsBootInterface, WhatsImported name)
357 data WhatsImported name = NothingAtAll -- The module is below us in the
358 -- hierarchy, but we import nothing
360 | Everything Version -- Used for modules from other packages;
361 -- we record only the module's version number
364 Version -- Module version
365 (Maybe Version) -- Export-list version, if we depend on it
366 [(name,Version)] -- List guaranteed non-empty
367 Version -- Rules version
370 -- 'Specifically' doesn't let you say "I imported f but none of the rules in
371 -- the module". If you use anything in the module you get its rule version
372 -- So if the rules change, you'll recompile, even if you don't use them.
373 -- This is easy to implement, and it's safer: you might not have used the rules last
374 -- time round, but if someone has added a new rule you might need it this time
376 -- The export list field is (Just v) if we depend on the export list:
377 -- we imported the module without saying exactly what we imported
378 -- We need to recompile if the module exports changes, because we might
379 -- now have a name clash in the importing module.
383 %************************************************************************
385 \subsection{The persistent compiler state}
387 %************************************************************************
390 data PersistentCompilerState
392 pcs_PIT :: PackageIfaceTable, -- Domain = non-home-package modules
393 -- the mi_decls component is empty
395 pcs_PTE :: PackageTypeEnv, -- Domain = non-home-package modules
396 -- except that the InstEnv components is empty
398 pcs_insts :: PackageInstEnv, -- The total InstEnv accumulated from all
399 -- the non-home-package modules
401 pcs_rules :: PackageRuleBase, -- Ditto RuleEnv
403 pcs_PRS :: PersistentRenamerState
408 The @PersistentRenamerState@ persists across successive calls to the
412 * A name supply, which deals with allocating unique names to
413 (Module,OccName) original names,
415 * An accumulated TypeEnv from all the modules in imported packages
417 * An accumulated InstEnv from all the modules in imported packages
418 The point is that we don't want to keep recreating it whenever
419 we compile a new module. The InstEnv component of pcPST is empty.
420 (This means we might "see" instances that we shouldn't "really" see;
421 but the Haskell Report is vague on what is meant to be visible,
422 so we just take the easy road here.)
426 * A "holding pen" for declarations that have been read out of
427 interface files but not yet sucked in, renamed, and typechecked
430 type PackageTypeEnv = TypeEnv
431 type PackageRuleBase = RuleBase
432 type PackageInstEnv = InstEnv
434 data PersistentRenamerState
435 = PRS { prsOrig :: OrigNameEnv,
436 prsDecls :: DeclsMap,
437 prsInsts :: IfaceInsts,
438 prsRules :: IfaceRules,
443 The OrigNameEnv makes sure that there is just one Unique assigned for
444 each original name; i.e. (module-name, occ-name) pair. The Name is
445 always stored as a Global, and has the SrcLoc of its binding location.
446 Actually that's not quite right. When we first encounter the original
447 name, we might not be at its binding site (e.g. we are reading an
448 interface file); so we give it 'noSrcLoc' then. Later, when we find
449 its binding site, we fix it up.
451 Exactly the same is true of the Module stored in the Name. When we first
452 encounter the occurrence, we may not know the details of the module, so
453 we just store junk. Then when we find the binding site, we fix it up.
457 = Orig { origNames :: OrigNameNameEnv,
458 -- Ensures that one original name gets one unique
459 origIParam :: OrigNameIParamEnv
460 -- Ensures that one implicit parameter name gets one unique
463 type OrigNameNameEnv = FiniteMap (ModuleName,OccName) Name
464 type OrigNameIParamEnv = FiniteMap OccName Name
468 A DeclsMap contains a binding for each Name in the declaration
469 including the constructors of a type decl etc. The Bool is True just
473 type DeclsMap = (NameEnv (AvailInfo, Bool, (Module, RdrNameTyClDecl)), Int)
474 -- The Int says how many have been sucked in
476 type IfaceInsts = GatedDecls RdrNameInstDecl
477 type IfaceRules = GatedDecls RdrNameRuleDecl
479 type GatedDecls d = (Bag (GatedDecl d), Int) -- The Int says how many have been sucked in
480 type GatedDecl d = ([Name], (Module, d))
484 %************************************************************************
486 \subsection{Provenance and export info}
488 %************************************************************************
490 The GlobalRdrEnv gives maps RdrNames to Names. There is a separate
491 one for each module, corresponding to that module's top-level scope.
494 type GlobalRdrEnv = RdrNameEnv [(Name,Provenance)] -- The list is because there may be name clashes
495 -- These only get reported on lookup,
496 -- not on construction
499 The "provenance" of something says how it came to be in scope.
503 = LocalDef -- Defined locally
505 | NonLocalDef -- Defined non-locally
509 -- Just used for grouping error messages (in RnEnv.warnUnusedBinds)
510 instance Eq Provenance where
511 p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False
513 instance Eq ImportReason where
514 p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False
516 instance Ord Provenance where
517 compare LocalDef LocalDef = EQ
518 compare LocalDef (NonLocalDef _ _) = LT
519 compare (NonLocalDef _ _) LocalDef = GT
521 compare (NonLocalDef reason1 _) (NonLocalDef reason2 _)
522 = compare reason1 reason2
524 instance Ord ImportReason where
525 compare ImplicitImport ImplicitImport = EQ
526 compare ImplicitImport (UserImport _ _ _) = LT
527 compare (UserImport _ _ _) ImplicitImport = GT
528 compare (UserImport m1 loc1 _) (UserImport m2 loc2 _)
529 = (m1 `compare` m2) `thenCmp` (loc1 `compare` loc2)
533 = UserImport Module SrcLoc Bool -- Imported from module M on line L
534 -- Note the M may well not be the defining module
536 -- The Bool is true iff the thing was named *explicitly* in the import spec,
537 -- rather than being imported as part of a group; e.g.
540 -- Here, everything imported by B, and the constructors of T
541 -- are not named explicitly; only T is named explicitly.
542 -- This info is used when warning of unused names.
544 | ImplicitImport -- Imported implicitly for some other reason
547 type PrintUnqualified = Bool -- True <=> the unqualified name of this thing is
548 -- in scope in this module, so print it
549 -- unqualified in error messages
553 hasBetterProv :: Provenance -> Provenance -> Bool
555 -- a local thing over an imported thing
556 -- a user-imported thing over a non-user-imported thing
557 -- an explicitly-imported thing over an implicitly imported thing
558 hasBetterProv LocalDef _ = True
559 hasBetterProv (NonLocalDef (UserImport _ _ True) _) _ = True
560 hasBetterProv (NonLocalDef (UserImport _ _ _ ) _) (NonLocalDef ImplicitImport _) = True
561 hasBetterProv _ _ = False
563 pprNameProvenance :: Name -> Provenance -> SDoc
564 pprNameProvenance name LocalDef = ptext SLIT("defined at") <+> ppr (nameSrcLoc name)
565 pprNameProvenance name (NonLocalDef why _) = sep [ppr_reason why,
566 nest 2 (parens (ppr_defn (nameSrcLoc name)))]
568 ppr_reason ImplicitImport = ptext SLIT("implicitly imported")
569 ppr_reason (UserImport mod loc _) = ptext SLIT("imported from") <+> ppr mod <+> ptext SLIT("at") <+> ppr loc
571 ppr_defn loc | isGoodSrcLoc loc = ptext SLIT("at") <+> ppr loc