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,
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 )
58 import TyCon ( TyCon )
60 import BasicTypes ( Version, initialVersion, Fixity )
62 import HsSyn ( DeprecTxt, tyClDeclName, ifaceRuleDeclName )
63 import RdrHsSyn ( RdrNameInstDecl, RdrNameRuleDecl, RdrNameTyClDecl )
64 import RnHsSyn ( RenamedTyClDecl, RenamedRuleDecl, RenamedInstDecl )
66 import CoreSyn ( IdCoreRule )
68 import FiniteMap ( FiniteMap )
70 import Maybes ( seqMaybe )
72 import SrcLoc ( SrcLoc, isGoodSrcLoc )
73 import Util ( thenCmp, sortLt )
74 import UniqSupply ( UniqSupply )
77 %************************************************************************
79 \subsection{Module locations}
81 %************************************************************************
86 ml_hs_file :: Maybe FilePath,
87 ml_hspp_file :: Maybe FilePath, -- path of preprocessed source
88 ml_hi_file :: Maybe FilePath,
89 ml_obj_file :: Maybe FilePath
93 instance Outputable ModuleLocation where
97 For a module in another package, the hs_file and obj_file
98 components of ModuleLocation are undefined.
100 The locations specified by a ModuleLocation may or may not
101 correspond to actual files yet: for example, even if the object
102 file doesn't exist, the ModuleLocation still contains the path to
103 where the object file will reside if/when it is created.
106 %************************************************************************
108 \subsection{Symbol tables and Module details}
110 %************************************************************************
112 A @ModIface@ plus a @ModDetails@ summarises everything we know
113 about a compiled module. The @ModIface@ is the stuff *before* linking,
114 and can be written out to an interface file. The @ModDetails@ is after
115 linking; it is the "linked" form of the mi_decls field.
120 mi_module :: Module, -- Complete with package info
121 mi_version :: VersionInfo, -- Module version number
122 mi_orphan :: WhetherHasOrphans, -- Whether this module has orphans
123 mi_boot :: IsBootInterface, -- Whether this interface was read from an hi-boot file
125 mi_usages :: [ImportVersion Name], -- Usages; kept sorted so that it's easy
126 -- to decide whether to write a new iface file
127 -- (changing usages doesn't affect the version of
130 mi_exports :: [(ModuleName,Avails)], -- What it exports
131 -- Kept sorted by (mod,occ),
132 -- to make version comparisons easier
134 mi_globals :: GlobalRdrEnv, -- Its top level environment
136 mi_fixities :: NameEnv Fixity, -- Fixities
137 mi_deprecs :: Deprecations, -- Deprecations
139 mi_decls :: IfaceDecls -- The RnDecls form of ModDetails
142 data IfaceDecls = IfaceDecls { dcl_tycl :: [RenamedTyClDecl], -- Sorted
143 dcl_rules :: [RenamedRuleDecl], -- Sorted
144 dcl_insts :: [RenamedInstDecl] } -- Unsorted
146 mkIfaceDecls :: [RenamedTyClDecl] -> [RenamedRuleDecl] -> [RenamedInstDecl] -> IfaceDecls
147 mkIfaceDecls tycls rules insts
148 = IfaceDecls { dcl_tycl = sortLt lt_tycl tycls,
149 dcl_rules = sortLt lt_rule rules,
152 d1 `lt_tycl` d2 = nameOccName (tyClDeclName d1) < nameOccName (tyClDeclName d2)
153 r1 `lt_rule` r2 = nameOccName (ifaceRuleDeclName r1) < nameOccName (ifaceRuleDeclName r2)
155 -- I wanted to sort just by the Name, but there's a problem: we are comparing
156 -- the old version of an interface with the new version. The latter will use
157 -- local names like 'lvl23' that were constructed not by the renamer but by
158 -- the simplifier. So the unqiues aren't going to line up.
160 -- It's ok to compare by OccName because this comparison only drives the
161 -- computation of new version numbers.
163 -- Better solutions: Compare in a way that is insensitive to the name used
164 -- for local things. This would decrease the wobbles due
165 -- to 'lvl23' changing to 'lvl24'.
167 -- NB: there's a related comparision on MkIface.diffDecls!
172 -- typechecker should only look at this, not ModIface
173 -- Should be able to construct ModDetails from mi_decls in ModIface
176 -- The next three fields are created by the typechecker
178 md_insts :: [DFunId], -- Dfun-ids for the instances in this module
179 md_rules :: [IdCoreRule] -- Domain may include Ids from other modules
184 emptyModDetails :: ModDetails
186 = ModDetails { md_types = emptyTypeEnv,
191 emptyModIface :: Module -> ModIface
193 = ModIface { mi_module = mod,
194 mi_version = initialVersionInfo,
199 mi_fixities = emptyNameEnv,
200 mi_globals = emptyRdrEnv,
201 mi_deprecs = NoDeprecs,
202 mi_decls = panic "emptyModIface: decls"
206 Symbol tables map modules to ModDetails:
209 type SymbolTable = ModuleEnv ModDetails
210 type IfaceTable = ModuleEnv ModIface
212 type HomeIfaceTable = IfaceTable
213 type PackageIfaceTable = IfaceTable
215 type HomeSymbolTable = SymbolTable -- Domain = modules in the home package
217 emptyIfaceTable :: IfaceTable
218 emptyIfaceTable = emptyModuleEnv
221 Simple lookups in the symbol table.
224 lookupIface :: HomeIfaceTable -> PackageIfaceTable -> Name -> Maybe ModIface
225 -- We often have two IfaceTables, and want to do a lookup
226 lookupIface hit pit name
227 = lookupModuleEnv hit mod `seqMaybe` lookupModuleEnv pit mod
229 mod = nameModule name
231 lookupIfaceByModName :: HomeIfaceTable -> PackageIfaceTable -> ModuleName -> Maybe ModIface
232 -- We often have two IfaceTables, and want to do a lookup
233 lookupIfaceByModName hit pit mod
234 = lookupModuleEnvByName hit mod `seqMaybe` lookupModuleEnvByName pit mod
238 %************************************************************************
240 \subsection{Type environment stuff}
242 %************************************************************************
245 data TyThing = AnId Id
249 isTyClThing :: TyThing -> Bool
250 isTyClThing (ATyCon _) = True
251 isTyClThing (AClass _) = True
252 isTyClThing (AnId _) = False
254 instance NamedThing TyThing where
255 getName (AnId id) = getName id
256 getName (ATyCon tc) = getName tc
257 getName (AClass cl) = getName cl
259 typeEnvClasses env = [cl | AClass cl <- nameEnvElts env]
260 typeEnvTyCons env = [tc | ATyCon tc <- nameEnvElts env]
266 type TypeEnv = NameEnv TyThing
268 emptyTypeEnv = emptyNameEnv
270 mkTypeEnv :: [TyThing] -> TypeEnv
271 mkTypeEnv things = extendTypeEnvList emptyTypeEnv things
273 extendTypeEnvList :: TypeEnv -> [TyThing] -> TypeEnv
274 extendTypeEnvList env things
275 = foldl add_thing env things
277 add_thing :: TypeEnv -> TyThing -> TypeEnv
278 add_thing env thing = extendNameEnv env (getName thing) thing
282 lookupType :: HomeSymbolTable -> PackageTypeEnv -> Name -> Maybe TyThing
283 lookupType hst pte name
284 = case lookupModuleEnv hst (nameModule name) of
285 Just details -> lookupNameEnv (md_types details) name
286 Nothing -> lookupNameEnv pte name
289 %************************************************************************
291 \subsection{Auxiliary types}
293 %************************************************************************
295 These types are defined here because they are mentioned in ModDetails,
296 but they are mostly elaborated elsewhere
301 vers_module :: Version, -- Changes when anything changes
302 vers_exports :: Version, -- Changes when export list changes
303 vers_rules :: Version, -- Changes when any rule changes
304 vers_decls :: NameEnv Version
305 -- Versions for "big" names only (not data constructors, class ops)
306 -- The version of an Id changes if its fixity changes
307 -- Ditto data constructors, class operations, except that the version of
308 -- the parent class/tycon changes
311 initialVersionInfo :: VersionInfo
312 initialVersionInfo = VersionInfo { vers_module = initialVersion,
313 vers_exports = initialVersion,
314 vers_rules = initialVersion,
315 vers_decls = emptyNameEnv }
317 data Deprecations = NoDeprecs
318 | DeprecAll DeprecTxt -- Whole module deprecated
319 | DeprecSome (NameEnv (Name,DeprecTxt)) -- Some things deprecated
321 -- We keep the Name in the range, so we can print them out
323 lookupDeprec :: Deprecations -> Name -> Maybe DeprecTxt
324 lookupDeprec NoDeprecs name = Nothing
325 lookupDeprec (DeprecAll txt) name = Just txt
326 lookupDeprec (DeprecSome env) name = case lookupNameEnv env name of
327 Just (_, txt) -> Just txt
333 type Avails = [AvailInfo]
334 type AvailInfo = GenAvailInfo Name
335 type RdrAvailInfo = GenAvailInfo OccName
337 data GenAvailInfo name = Avail name -- An ordinary identifier
338 | AvailTC name -- The name of the type or class
339 [name] -- The available pieces of type/class.
340 -- NB: If the type or class is itself
341 -- to be in scope, it must be in this list.
342 -- Thus, typically: AvailTC Eq [Eq, ==, /=]
344 -- Equality used when deciding if the interface has changed
346 type AvailEnv = NameEnv AvailInfo -- Maps a Name to the AvailInfo that contains it
348 instance Outputable n => Outputable (GenAvailInfo n) where
351 pprAvail :: Outputable n => GenAvailInfo n -> SDoc
352 pprAvail (AvailTC n ns) = ppr n <> case {- filter (/= n) -} ns of
354 ns' -> braces (hsep (punctuate comma (map ppr ns')))
356 pprAvail (Avail n) = ppr n
360 %************************************************************************
362 \subsection{ModIface}
364 %************************************************************************
367 type WhetherHasOrphans = Bool
369 -- * an instance decl in a module other than the defn module for
370 -- one of the tycons or classes in the instance head
371 -- * a transformation rule in a module other than the one defining
372 -- the function in the head of the rule.
374 type IsBootInterface = Bool
376 type ImportVersion name = (ModuleName, WhetherHasOrphans, IsBootInterface, WhatsImported name)
378 data WhatsImported name = NothingAtAll -- The module is below us in the
379 -- hierarchy, but we import nothing
381 | Everything Version -- Used for modules from other packages;
382 -- we record only the module's version number
385 Version -- Module version
386 (Maybe Version) -- Export-list version, if we depend on it
387 [(name,Version)] -- List guaranteed non-empty
388 Version -- Rules version
391 -- 'Specifically' doesn't let you say "I imported f but none of the rules in
392 -- the module". If you use anything in the module you get its rule version
393 -- So if the rules change, you'll recompile, even if you don't use them.
394 -- This is easy to implement, and it's safer: you might not have used the rules last
395 -- time round, but if someone has added a new rule you might need it this time
397 -- The export list field is (Just v) if we depend on the export list:
398 -- we imported the module without saying exactly what we imported
399 -- We need to recompile if the module exports changes, because we might
400 -- now have a name clash in the importing module.
402 type IsExported = Name -> Bool -- True for names that are exported from this module
406 %************************************************************************
408 \subsection{The persistent compiler state}
410 %************************************************************************
413 data PersistentCompilerState
415 pcs_PIT :: PackageIfaceTable, -- Domain = non-home-package modules
416 -- the mi_decls component is empty
418 pcs_PTE :: PackageTypeEnv, -- Domain = non-home-package modules
419 -- except that the InstEnv components is empty
421 pcs_insts :: PackageInstEnv, -- The total InstEnv accumulated from all
422 -- the non-home-package modules
424 pcs_rules :: PackageRuleBase, -- Ditto RuleEnv
426 pcs_PRS :: PersistentRenamerState
431 The @PersistentRenamerState@ persists across successive calls to the
435 * A name supply, which deals with allocating unique names to
436 (Module,OccName) original names,
438 * An accumulated TypeEnv from all the modules in imported packages
440 * An accumulated InstEnv from all the modules in imported packages
441 The point is that we don't want to keep recreating it whenever
442 we compile a new module. The InstEnv component of pcPST is empty.
443 (This means we might "see" instances that we shouldn't "really" see;
444 but the Haskell Report is vague on what is meant to be visible,
445 so we just take the easy road here.)
449 * A "holding pen" for declarations that have been read out of
450 interface files but not yet sucked in, renamed, and typechecked
453 type PackageTypeEnv = TypeEnv
454 type PackageRuleBase = RuleBase
455 type PackageInstEnv = InstEnv
457 data PersistentRenamerState
458 = PRS { prsOrig :: OrigNameEnv,
459 prsDecls :: DeclsMap,
460 prsInsts :: IfaceInsts,
461 prsRules :: IfaceRules,
466 The OrigNameEnv makes sure that there is just one Unique assigned for
467 each original name; i.e. (module-name, occ-name) pair. The Name is
468 always stored as a Global, and has the SrcLoc of its binding location.
469 Actually that's not quite right. When we first encounter the original
470 name, we might not be at its binding site (e.g. we are reading an
471 interface file); so we give it 'noSrcLoc' then. Later, when we find
472 its binding site, we fix it up.
474 Exactly the same is true of the Module stored in the Name. When we first
475 encounter the occurrence, we may not know the details of the module, so
476 we just store junk. Then when we find the binding site, we fix it up.
480 = Orig { origNames :: OrigNameNameEnv,
481 -- Ensures that one original name gets one unique
482 origIParam :: OrigNameIParamEnv
483 -- Ensures that one implicit parameter name gets one unique
486 type OrigNameNameEnv = FiniteMap (ModuleName,OccName) Name
487 type OrigNameIParamEnv = FiniteMap OccName Name
491 A DeclsMap contains a binding for each Name in the declaration
492 including the constructors of a type decl etc. The Bool is True just
496 type DeclsMap = (NameEnv (AvailInfo, Bool, (Module, RdrNameTyClDecl)), Int)
497 -- The Int says how many have been sucked in
499 type IfaceInsts = GatedDecls RdrNameInstDecl
500 type IfaceRules = GatedDecls RdrNameRuleDecl
502 type GatedDecls d = (Bag (GatedDecl d), Int) -- The Int says how many have been sucked in
503 type GatedDecl d = ([Name], (Module, d))
507 %************************************************************************
509 \subsection{Provenance and export info}
511 %************************************************************************
513 The GlobalRdrEnv gives maps RdrNames to Names. There is a separate
514 one for each module, corresponding to that module's top-level scope.
517 type GlobalRdrEnv = RdrNameEnv [(Name,Provenance)] -- The list is because there may be name clashes
518 -- These only get reported on lookup,
519 -- not on construction
522 = vcat (map pp (rdrEnvToList env))
524 pp (rn, nps) = ppr rn <> colon <+>
525 vcat [ppr n <+> pprNameProvenance n p | (n,p) <- nps]
528 The "provenance" of something says how it came to be in scope.
532 = LocalDef -- Defined locally
534 | NonLocalDef -- Defined non-locally
537 -- Just used for grouping error messages (in RnEnv.warnUnusedBinds)
538 instance Eq Provenance where
539 p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False
541 instance Eq ImportReason where
542 p1 == p2 = case p1 `compare` p2 of EQ -> True; _ -> False
544 instance Ord Provenance where
545 compare LocalDef LocalDef = EQ
546 compare LocalDef (NonLocalDef _) = LT
547 compare (NonLocalDef _) LocalDef = GT
549 compare (NonLocalDef reason1) (NonLocalDef reason2)
550 = compare reason1 reason2
552 instance Ord ImportReason where
553 compare ImplicitImport ImplicitImport = EQ
554 compare ImplicitImport (UserImport _ _ _) = LT
555 compare (UserImport _ _ _) ImplicitImport = GT
556 compare (UserImport m1 loc1 _) (UserImport m2 loc2 _)
557 = (m1 `compare` m2) `thenCmp` (loc1 `compare` loc2)
561 = UserImport Module SrcLoc Bool -- Imported from module M on line L
562 -- Note the M may well not be the defining module
564 -- The Bool is true iff the thing was named *explicitly* in the import spec,
565 -- rather than being imported as part of a group; e.g.
568 -- Here, everything imported by B, and the constructors of T
569 -- are not named explicitly; only T is named explicitly.
570 -- This info is used when warning of unused names.
572 | ImplicitImport -- Imported implicitly for some other reason
576 hasBetterProv :: Provenance -> Provenance -> Bool
578 -- a local thing over an imported thing
579 -- a user-imported thing over a non-user-imported thing
580 -- an explicitly-imported thing over an implicitly imported thing
581 hasBetterProv LocalDef _ = True
582 hasBetterProv (NonLocalDef (UserImport _ _ _ )) (NonLocalDef ImplicitImport) = True
583 hasBetterProv _ _ = False
585 pprNameProvenance :: Name -> Provenance -> SDoc
586 pprNameProvenance name LocalDef = ptext SLIT("defined at") <+> ppr (nameSrcLoc name)
587 pprNameProvenance name (NonLocalDef why) = sep [ppr_reason why,
588 nest 2 (parens (ppr_defn (nameSrcLoc name)))]
590 ppr_reason ImplicitImport = ptext SLIT("implicitly imported")
591 ppr_reason (UserImport mod loc _) = ptext SLIT("imported from") <+> ppr mod <+> ptext SLIT("at") <+> ppr loc
593 ppr_defn loc | isGoodSrcLoc loc = ptext SLIT("at") <+> ppr loc