2 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
4 \section[RnIfaces]{Cacheing and Renaming of Interfaces}
9 getImportedInstDecls, getImportedRules,
10 lookupFixity, loadHomeInterface,
11 importDecl, recordSlurp,
12 getImportVersions, getSlurped,
19 #include "HsVersions.h"
21 import CmdLineOpts ( opt_NoPruneDecls, opt_IgnoreIfacePragmas )
22 import HsSyn ( HsDecl(..), TyClDecl(..), InstDecl(..), IfaceSig(..),
23 HsType(..), ConDecl(..), IE(..), ConDetails(..), Sig(..),
24 FixitySig(..), RuleDecl(..),
27 import BasicTypes ( Version, NewOrData(..), defaultFixity )
28 import RdrHsSyn ( RdrNameHsDecl, RdrNameInstDecl, RdrNameTyClDecl, RdrNameRuleDecl,
31 import RnEnv ( mkImportedGlobalName, newImportedBinder, mkImportedGlobalFromRdrName,
34 availName, availNames, addAvailToNameSet,
38 import RnHsSyn ( RenamedHsDecl )
39 import ParseIface ( parseIface, IfaceStuff(..) )
41 import FiniteMap ( FiniteMap, sizeFM, emptyFM, delFromFM,
42 lookupFM, addToFM, addToFM_C, addListToFM,
43 fmToList, elemFM, foldFM
45 import Name ( Name {-instance NamedThing-},
46 nameModule, isLocallyDefined,
47 isWiredInName, nameUnique, NamedThing(..)
49 import Module ( Module, moduleString, pprModule,
50 mkVanillaModule, pprModuleName,
51 moduleUserString, moduleName, isLibModule,
52 ModuleName, WhereFrom(..),
54 import RdrName ( RdrName, rdrNameOcc )
57 import SrcLoc ( mkSrcLoc, SrcLoc )
58 import PrelMods ( pREL_GHC )
59 import PrelInfo ( cCallishTyKeys, thinAirModules )
61 import Maybes ( MaybeErr(..), maybeToBool, orElse )
62 import ListSetOps ( unionLists )
64 import Unique ( Unique )
65 import StringBuffer ( StringBuffer, hGetStringBuffer )
66 import FastString ( mkFastString )
70 import IO ( isDoesNotExistError )
75 %*********************************************************
77 \subsection{Loading a new interface file}
79 %*********************************************************
82 loadHomeInterface :: SDoc -> Name -> RnM d (Module, Ifaces)
83 loadHomeInterface doc_str name
84 = loadInterface doc_str (moduleName (nameModule name)) ImportBySystem
86 loadInterface :: SDoc -> ModuleName -> WhereFrom -> RnM d (Module, Ifaces)
87 loadInterface doc_str mod_name from
88 = getIfacesRn `thenRn` \ ifaces ->
90 mod_map = iImpModInfo ifaces
91 mod_info = lookupFM mod_map mod_name
92 in_map = maybeToBool mod_info
95 -- Issue a warning for a redundant {- SOURCE -} import
96 -- It's redundant if the moduld is in the iImpModInfo at all,
97 -- because we arrange to read all the ordinary imports before
98 -- any of the {- SOURCE -} imports
99 warnCheckRn (not (in_map && case from of {ImportByUserSource -> True; other -> False}))
100 (warnRedundantSourceImport mod_name) `thenRn_`
102 -- CHECK WHETHER WE HAVE IT ALREADY
104 Just (_, _, Just (load_mod, _, _))
105 -> -- We're read it already so don't re-read it
106 returnRn (load_mod, ifaces) ;
110 -- READ THE MODULE IN
111 findAndReadIface doc_str mod_name from in_map `thenRn` \ (hi_boot_read, read_result) ->
112 case read_result of {
113 Nothing -> -- Not found, so add an empty export env to the Ifaces map
114 -- so that we don't look again
116 mod = mkVanillaModule mod_name
117 new_mod_map = addToFM mod_map mod_name (0, False, Just (mod, False, []))
118 new_ifaces = ifaces { iImpModInfo = new_mod_map }
120 setIfacesRn new_ifaces `thenRn_`
121 failWithRn (mod, new_ifaces) (noIfaceErr mod hi_boot_read) ;
126 -- LOAD IT INTO Ifaces
128 -- NB: *first* we do loadDecl, so that the provenance of all the locally-defined
129 --- names is done correctly (notably, whether this is an .hi file or .hi-boot file).
130 -- If we do loadExport first the wrong info gets into the cache (unless we
131 -- explicitly tag each export which seems a bit of a bore)
133 getModuleRn `thenRn` \ this_mod_nm ->
135 rd_decls = pi_decls iface
137 foldlRn (loadDecl mod) (iDecls ifaces) rd_decls `thenRn` \ new_decls ->
138 foldlRn (loadInstDecl mod) (iInsts ifaces) (pi_insts iface) `thenRn` \ new_insts ->
139 foldlRn (loadRule mod) (iRules ifaces) (pi_rules iface) `thenRn` \ new_rules ->
140 foldlRn (loadFixDecl mod_name) (iFixes ifaces) rd_decls `thenRn` \ new_fixities ->
141 mapRn (loadExport this_mod_nm) (pi_exports iface) `thenRn` \ avails_s ->
143 -- For an explicit user import, add to mod_map info about
144 -- the things the imported module depends on, extracted
145 -- from its usage info.
146 mod_map1 = case from of
147 ImportByUser -> addModDeps mod mod_map (pi_usages iface)
150 -- Now add info about this module
151 mod_map2 = addToFM mod_map1 mod_name mod_details
152 mod_details = (pi_mod iface, pi_orphan iface, Just (mod, hi_boot_read, concat avails_s))
154 new_ifaces = ifaces { iImpModInfo = mod_map2,
156 iFixes = new_fixities,
160 setIfacesRn new_ifaces `thenRn_`
161 returnRn (mod, new_ifaces)
164 addModDeps :: Module -> ImportedModuleInfo
165 -> [ImportVersion a] -> ImportedModuleInfo
166 addModDeps mod mod_deps new_deps
167 = foldr add mod_deps new_deps
169 is_lib = isLibModule mod -- Don't record dependencies when importing a library module
170 add (imp_mod, version, has_orphans, _) deps
171 | is_lib && not has_orphans = deps
172 | otherwise = addToFM_C combine deps imp_mod (version, has_orphans, Nothing)
173 -- Record dependencies for modules that are
174 -- either are dependent via a non-library module
175 -- or contain orphan rules or instance decls
177 -- Don't ditch a module that's already loaded!!
178 combine old@(_, _, Just _) new = old
179 combine old@(_, _, Nothing) new = new
181 loadExport :: ModuleName -> ExportItem -> RnM d [AvailInfo]
182 loadExport this_mod (mod, entities)
183 | mod == this_mod = returnRn []
184 -- If the module exports anything defined in this module, just ignore it.
185 -- Reason: otherwise it looks as if there are two local definition sites
186 -- for the thing, and an error gets reported. Easiest thing is just to
187 -- filter them out up front. This situation only arises if a module
188 -- imports itself, or another module that imported it. (Necessarily,
189 -- this invoves a loop.) Consequence: if you say
194 -- module B( AType ) where
195 -- import {-# SOURCE #-} A( AType )
197 -- then you'll get a 'B does not export AType' message. A bit bogus
198 -- but it's a bogus thing to do!
201 = mapRn (load_entity mod) entities
203 new_name mod occ = mkImportedGlobalName mod occ
205 load_entity mod (Avail occ)
206 = new_name mod occ `thenRn` \ name ->
207 returnRn (Avail name)
208 load_entity mod (AvailTC occ occs)
209 = new_name mod occ `thenRn` \ name ->
210 mapRn (new_name mod) occs `thenRn` \ names ->
211 returnRn (AvailTC name names)
214 loadFixDecl :: ModuleName -> FixityEnv
215 -> (Version, RdrNameHsDecl)
217 loadFixDecl mod_name fixity_env (version, FixD sig@(FixitySig rdr_name fixity loc))
218 = -- Ignore the version; when the fixity changes the version of
219 -- its 'host' entity changes, so we don't need a separate version
220 -- number for fixities
221 mkImportedGlobalName mod_name (rdrNameOcc rdr_name) `thenRn` \ name ->
223 new_fixity_env = addToNameEnv fixity_env name (FixitySig name fixity loc)
225 returnRn new_fixity_env
227 -- Ignore the other sorts of decl
228 loadFixDecl mod_name fixity_env other_decl = returnRn fixity_env
232 -> (Version, RdrNameHsDecl)
235 loadDecl mod decls_map (version, decl)
236 = getDeclBinders new_name decl `thenRn` \ maybe_avail ->
237 case maybe_avail of {
238 Nothing -> returnRn decls_map; -- No bindings
241 getDeclSysBinders new_name decl `thenRn` \ sys_bndrs ->
243 main_name = availName avail
244 new_decls_map = foldl add_decl decls_map
245 [ (name, (version, avail, name==main_name, (mod, decl')))
246 | name <- sys_bndrs ++ availNames avail]
247 add_decl decls_map (name, stuff)
248 = WARN( name `elemNameEnv` decls_map, ppr name )
249 addToNameEnv decls_map name stuff
251 returnRn new_decls_map
254 -- newImportedBinder puts into the cache the binder with the
255 -- module information set correctly. When the decl is later renamed,
256 -- the binding site will thereby get the correct module.
257 new_name rdr_name loc = newImportedBinder mod rdr_name
260 If a signature decl is being loaded, and optIgnoreIfacePragmas is on,
261 we toss away unfolding information.
263 Also, if the signature is loaded from a module we're importing from source,
264 we do the same. This is to avoid situations when compiling a pair of mutually
265 recursive modules, peering at unfolding info in the interface file of the other,
266 e.g., you compile A, it looks at B's interface file and may as a result change
267 its interface file. Hence, B is recompiled, maybe changing its interface file,
268 which will the unfolding info used in A to become invalid. Simple way out is to
269 just ignore unfolding info.
271 [Jan 99: I junked the second test above. If we're importing from an hi-boot
272 file there isn't going to *be* any pragma info. Maybe the above comment
273 dates from a time where we picked up a .hi file first if it existed?]
276 SigD (IfaceSig name tp ls loc) | opt_IgnoreIfacePragmas -> SigD (IfaceSig name tp [] loc)
279 loadInstDecl :: Module
282 -> RnM d (Bag GatedDecl)
283 loadInstDecl mod insts decl@(InstDecl inst_ty binds uprags dfun_name src_loc)
285 -- Find out what type constructors and classes are "gates" for the
286 -- instance declaration. If all these "gates" are slurped in then
287 -- we should slurp the instance decl too.
289 -- We *don't* want to count names in the context part as gates, though.
291 -- instance Foo a => Baz (T a) where ...
293 -- Here the gates are Baz and T, but *not* Foo.
295 munged_inst_ty = removeContext inst_ty
296 free_names = extractHsTyRdrNames munged_inst_ty
298 setModuleRn (moduleName mod) $
299 mapRn mkImportedGlobalFromRdrName free_names `thenRn` \ gate_names ->
300 returnRn ((mkNameSet gate_names, (mod, InstD decl)) `consBag` insts)
303 -- In interface files, the instance decls now look like
304 -- forall a. Foo a -> Baz (T a)
305 -- so we have to strip off function argument types as well
306 -- as the bit before the '=>' (which is always empty in interface files)
307 removeContext (HsForAllTy tvs cxt ty) = HsForAllTy tvs [] (removeFuns ty)
308 removeContext ty = removeFuns ty
310 removeFuns (MonoFunTy _ ty) = removeFuns ty
314 loadRule :: Module -> Bag GatedDecl
315 -> RdrNameRuleDecl -> RnM d (Bag GatedDecl)
316 -- "Gate" the rule simply by whether the rule variable is
317 -- needed. We can refine this later.
318 loadRule mod rules decl@(IfaceRuleDecl var body src_loc)
319 = setModuleRn (moduleName mod) $
320 mkImportedGlobalFromRdrName var `thenRn` \ var_name ->
321 returnRn ((unitNameSet var_name, (mod, RuleD decl)) `consBag` rules)
325 %********************************************************
327 \subsection{Loading usage information}
329 %********************************************************
332 checkUpToDate :: ModuleName -> RnMG Bool -- True <=> no need to recompile
333 checkUpToDate mod_name
334 = getIfacesRn `thenRn` \ ifaces ->
335 findAndReadIface doc_str mod_name
337 (error "checkUpToDate") `thenRn` \ (_, read_result) ->
339 -- CHECK WHETHER WE HAVE IT ALREADY
341 Nothing -> -- Old interface file not found, so we'd better bail out
342 traceRn (sep [ptext SLIT("Didnt find old iface"),
343 pprModuleName mod_name]) `thenRn_`
347 -> -- Found it, so now check it
348 checkModUsage (pi_usages iface)
350 -- Only look in current directory, with suffix .hi
351 doc_str = sep [ptext SLIT("need usage info from"), pprModuleName mod_name]
353 checkModUsage [] = returnRn True -- Yes! Everything is up to date!
355 checkModUsage ((mod_name, old_mod_vers, _, whats_imported) : rest)
356 = loadInterface doc_str mod_name ImportBySystem `thenRn` \ (mod, ifaces) ->
358 maybe_mod_vers = case lookupFM (iImpModInfo ifaces) mod_name of
359 Just (version, _, Just (_, _, _)) -> Just version
362 case maybe_mod_vers of {
363 Nothing -> -- If we can't find a version number for the old module then
364 -- bail out saying things aren't up to date
365 traceRn (sep [ptext SLIT("Can't find version number for module"),
366 pprModuleName mod_name]) `thenRn_`
371 -- If the module version hasn't changed, just move on
372 if new_mod_vers == old_mod_vers then
373 traceRn (sep [ptext SLIT("Module version unchanged:"), pprModuleName mod_name]) `thenRn_`
376 traceRn (sep [ptext SLIT("Module version has changed:"), pprModuleName mod_name]) `thenRn_`
378 -- Module version changed, so check entities inside
380 -- If the usage info wants to say "I imported everything from this module"
381 -- it does so by making whats_imported equal to Everything
382 -- In that case, we must recompile
383 case whats_imported of {
384 Everything -> traceRn (ptext SLIT("...and I needed the whole module")) `thenRn_`
385 returnRn False; -- Bale out
387 Specifically old_local_vers ->
389 -- Non-empty usage list, so check item by item
390 checkEntityUsage mod_name (iDecls ifaces) old_local_vers `thenRn` \ up_to_date ->
392 traceRn (ptext SLIT("...but the bits I use haven't.")) `thenRn_`
393 checkModUsage rest -- This one's ok, so check the rest
395 returnRn False -- This one failed, so just bail out now
398 doc_str = sep [ptext SLIT("need version info for"), pprModuleName mod_name]
401 checkEntityUsage mod decls []
402 = returnRn True -- Yes! All up to date!
404 checkEntityUsage mod decls ((occ_name,old_vers) : rest)
405 = mkImportedGlobalName mod occ_name `thenRn` \ name ->
406 case lookupNameEnv decls name of
408 Nothing -> -- We used it before, but it ain't there now
409 putDocRn (sep [ptext SLIT("No longer exported:"), ppr name]) `thenRn_`
412 Just (new_vers,_,_,_) -- It's there, but is it up to date?
413 | new_vers == old_vers
414 -- Up to date, so check the rest
415 -> checkEntityUsage mod decls rest
418 -- Out of date, so bale out
419 -> putDocRn (sep [ptext SLIT("Out of date:"), ppr name]) `thenRn_`
424 %*********************************************************
426 \subsection{Getting in a declaration}
428 %*********************************************************
431 importDecl :: Name -> RnMG (Maybe (Module, RdrNameHsDecl))
432 -- Returns Nothing for
435 -- (c) already slurped
441 = getSlurped `thenRn` \ already_slurped ->
442 if name `elemNameSet` already_slurped then
443 returnRn Nothing -- Already dealt with
445 getModuleRn `thenRn` \ this_mod ->
447 mod = moduleName (nameModule name)
449 if mod == this_mod then -- Don't bring in decls from
450 -- the renamed module's own interface file
451 addWarnRn (importDeclWarn mod name) `thenRn_`
454 getNonWiredInDecl name
458 getNonWiredInDecl :: Name -> RnMG (Maybe (Module, RdrNameHsDecl))
459 getNonWiredInDecl needed_name
460 = traceRn doc_str `thenRn_`
461 loadHomeInterface doc_str needed_name `thenRn` \ (_, ifaces) ->
462 case lookupNameEnv (iDecls ifaces) needed_name of
464 Just (version,avail,_,decl)
465 -> recordSlurp (Just version) avail `thenRn_`
468 Nothing -- Can happen legitimately for "Optional" occurrences
469 -> addErrRn (getDeclErr needed_name) `thenRn_`
472 doc_str = ptext SLIT("need decl for") <+> ppr needed_name
475 @getWiredInDecl@ maps a wired-in @Name@ to what it makes available.
476 It behaves exactly as if the wired in decl were actually in an interface file.
479 * if the wired-in name is a data type constructor or a data constructor,
480 it brings in the type constructor and all the data constructors; and
481 marks as "occurrences" any free vars of the data con.
483 * similarly for synonum type constructor
485 * if the wired-in name is another wired-in Id, it marks as "occurrences"
486 the free vars of the Id's type.
488 * it loads the interface file for the wired-in thing for the
489 sole purpose of making sure that its instance declarations are available
491 All this is necessary so that we know all types that are "in play", so
492 that we know just what instances to bring into scope.
497 %*********************************************************
499 \subsection{Getting what a module exports}
501 %*********************************************************
503 @getInterfaceExports@ is called only for directly-imported modules
506 getInterfaceExports :: ModuleName -> WhereFrom -> RnMG (Module, Avails)
507 getInterfaceExports mod_name from
508 = loadInterface doc_str mod_name from `thenRn` \ (mod, ifaces) ->
509 case lookupFM (iImpModInfo ifaces) mod_name of
510 Nothing -> -- Not there; it must be that the interface file wasn't found;
511 -- the error will have been reported already.
512 -- (Actually loadInterface should put the empty export env in there
513 -- anyway, but this does no harm.)
516 Just (_, _, Just (mod, _, avails)) -> returnRn (mod, avails)
518 doc_str = sep [pprModuleName mod_name, ptext SLIT("is directly imported")]
522 %*********************************************************
524 \subsection{Instance declarations are handled specially}
526 %*********************************************************
529 getImportedInstDecls :: NameSet -> RnMG [(Module,RdrNameHsDecl)]
530 getImportedInstDecls gates
531 = -- First load any orphan-instance modules that aren't aready loaded
532 -- Orphan-instance modules are recorded in the module dependecnies
533 getIfacesRn `thenRn` \ ifaces ->
535 orphan_mods = [mod | (mod, (_, True, Nothing)) <- fmToList (iImpModInfo ifaces)]
537 traceRn (text "Loading orphan modules" <+> fsep (map pprModuleName orphan_mods)) `thenRn_`
538 mapRn_ load_it orphan_mods `thenRn_`
540 -- Now we're ready to grab the instance declarations
541 -- Find the un-gated ones and return them,
542 -- removing them from the bag kept in Ifaces
543 getIfacesRn `thenRn` \ ifaces ->
545 (decls, new_insts) = selectGated gates (iInsts ifaces)
547 setIfacesRn (ifaces { iInsts = new_insts }) `thenRn_`
549 traceRn (sep [text "getImportedInstDecls:",
550 nest 4 (fsep (map ppr (nameSetToList gates))),
551 text "Slurped" <+> int (length decls) <+> text "instance declarations"]) `thenRn_`
554 load_it mod = loadInterface (doc_str mod) mod ImportBySystem
555 doc_str mod = sep [pprModuleName mod, ptext SLIT("is a orphan-instance module")]
557 getImportedRules :: RnMG [(Module,RdrNameHsDecl)]
559 = getIfacesRn `thenRn` \ ifaces ->
561 gates = iSlurp ifaces -- Anything at all that's been slurped
562 (decls, new_rules) = selectGated gates (iRules ifaces)
564 setIfacesRn (ifaces { iRules = new_rules }) `thenRn_`
565 traceRn (sep [text "getImportedRules:",
566 text "Slurped" <+> int (length decls) <+> text "rules"]) `thenRn_`
569 selectGated gates decl_bag
571 | opt_NoPruneDecls -- Just to try the effect of not gating at all
572 = (foldrBag (\ (_,d) ds -> d:ds) [] decl_bag, emptyBag) -- Grab them all
576 = foldrBag select ([], emptyBag) decl_bag
578 select (reqd, decl) (yes, no)
579 | isEmptyNameSet (reqd `minusNameSet` gates) = (decl:yes, no)
580 | otherwise = (yes, (reqd,decl) `consBag` no)
582 lookupFixity :: Name -> RnMS Fixity
584 | isLocallyDefined name
585 = getFixityEnv `thenRn` \ local_fix_env ->
586 case lookupNameEnv local_fix_env name of
587 Just (FixitySig _ fix _) -> returnRn fix
588 Nothing -> returnRn defaultFixity
590 | otherwise -- Imported
591 = loadHomeInterface doc name `thenRn` \ (_, ifaces) ->
592 case lookupNameEnv (iFixes ifaces) name of
593 Just (FixitySig _ fix _) -> returnRn fix
594 Nothing -> returnRn defaultFixity
596 doc = ptext SLIT("Checking fixity for") <+> ppr name
600 %*********************************************************
602 \subsection{Keeping track of what we've slurped, and version numbers}
604 %*********************************************************
606 getImportVersions figures out what the "usage information" for this moudule is;
607 that is, what it must record in its interface file as the things it uses.
609 - anything reachable from its body code
610 - any module exported with a "module Foo".
612 Why the latter? Because if Foo changes then this module's export list
613 will change, so we must recompile this module at least as far as
614 making a new interface file --- but in practice that means complete
618 module A( f, g ) where module B( f ) where
619 import B( f ) f = h 3
622 Should we record B.f in A's usages? In fact we don't. Certainly, if
623 anything about B.f changes than anyone who imports A should be recompiled;
624 they'll get an early exit if they don't use B.f. However, even if B.f
625 doesn't change at all, B.h may do so, and this change may not be reflected
626 in f's version number. So there are two things going on when compiling module A:
628 1. Are A.o and A.hi correct? Then we can bale out early.
629 2. Should modules that import A be recompiled?
631 For (1) it is slightly harmful to record B.f in A's usages, because a change in
632 B.f's version will provoke full recompilation of A, producing an identical A.o,
633 and A.hi differing only in its usage-version of B.f (which isn't used by any importer).
635 For (2), because of the tricky B.h question above, we ensure that A.hi is touched
636 (even if identical to its previous version) if A's recompilation was triggered by
637 an imported .hi file date change. Given that, there's no need to record B.f in
640 On the other hand, if A exports "module B" then we *do* count module B among
641 A's usages, because we must recompile A to ensure that A.hi changes appropriately.
644 getImportVersions :: ModuleName -- Name of this module
645 -> Maybe [IE any] -- Export list for this module
646 -> RnMG (VersionInfo Name) -- Version info for these names
648 getImportVersions this_mod exports
649 = getIfacesRn `thenRn` \ ifaces ->
651 mod_map = iImpModInfo ifaces
652 imp_names = iVSlurp ifaces
654 -- mv_map groups together all the things imported from a particular module.
655 mv_map1, mv_map2 :: FiniteMap ModuleName (WhatsImported Name)
657 -- mv_map1 records all the modules that have a "module M"
658 -- in this module's export list with an "Everything"
659 mv_map1 = foldr add_mod emptyFM export_mods
661 -- mv_map2 adds the version numbers of things exported individually
662 mv_map2 = foldr add_mv mv_map1 imp_names
664 -- Build the result list by adding info for each module,
665 -- *omitting* (a) library modules
666 -- (b) source-imported modules
667 mk_version_info mod_name (version, has_orphans, cts) so_far
668 | omit cts = so_far -- Don't record usage info for this module
669 | otherwise = (mod_name, version, has_orphans, whats_imported) : so_far
671 whats_imported = case lookupFM mv_map2 mod_name of
673 Nothing -> Specifically []
675 omit (Just (mod, boot_import, _)) = isLibModule mod || boot_import
678 returnRn (foldFM mk_version_info [] mod_map)
680 export_mods = case exports of
682 Just es -> [mod | IEModuleContents mod <- es, mod /= this_mod]
684 add_mv v@(name, version) mv_map
685 = addToFM_C add_item mv_map mod (Specifically [v])
687 mod = moduleName (nameModule name)
689 add_item Everything _ = Everything
690 add_item (Specifically xs) _ = Specifically (v:xs)
692 add_mod mod mv_map = addToFM mv_map mod Everything
697 = getIfacesRn `thenRn` \ ifaces ->
698 returnRn (iSlurp ifaces)
700 recordSlurp maybe_version avail
701 = getIfacesRn `thenRn` \ ifaces@(Ifaces { iSlurp = slurped_names,
702 iVSlurp = imp_names }) ->
704 new_slurped_names = addAvailToNameSet slurped_names avail
706 new_imp_names = case maybe_version of
707 Just version -> (availName avail, version) : imp_names
710 setIfacesRn (ifaces { iSlurp = new_slurped_names,
711 iVSlurp = new_imp_names })
715 %*********************************************************
717 \subsection{Getting binders out of a declaration}
719 %*********************************************************
721 @getDeclBinders@ returns the names for a @RdrNameHsDecl@.
722 It's used for both source code (from @availsFromDecl@) and interface files
725 It doesn't deal with source-code specific things: ValD, DefD. They
726 are handled by the sourc-code specific stuff in RnNames.
729 getDeclBinders :: (RdrName -> SrcLoc -> RnM d Name) -- New-name function
731 -> RnM d (Maybe AvailInfo)
733 getDeclBinders new_name (TyClD (TyData _ _ tycon _ condecls _ _ src_loc))
734 = new_name tycon src_loc `thenRn` \ tycon_name ->
735 getConFieldNames new_name condecls `thenRn` \ sub_names ->
736 returnRn (Just (AvailTC tycon_name (tycon_name : nub sub_names)))
737 -- The "nub" is because getConFieldNames can legitimately return duplicates,
738 -- when a record declaration has the same field in multiple constructors
740 getDeclBinders new_name (TyClD (TySynonym tycon _ _ src_loc))
741 = new_name tycon src_loc `thenRn` \ tycon_name ->
742 returnRn (Just (AvailTC tycon_name [tycon_name]))
744 getDeclBinders new_name (TyClD (ClassDecl _ cname _ sigs _ _ _ _ _ src_loc))
745 = new_name cname src_loc `thenRn` \ class_name ->
747 -- Record the names for the class ops
749 -- just want class-op sigs
750 op_sigs = filter isClassOpSig sigs
752 mapRn (getClassOpNames new_name) op_sigs `thenRn` \ sub_names ->
754 returnRn (Just (AvailTC class_name (class_name : sub_names)))
756 getDeclBinders new_name (SigD (IfaceSig var ty prags src_loc))
757 = new_name var src_loc `thenRn` \ var_name ->
758 returnRn (Just (Avail var_name))
760 getDeclBinders new_name (FixD _) = returnRn Nothing
761 getDeclBinders new_name (ForD _) = returnRn Nothing
762 getDeclBinders new_name (DefD _) = returnRn Nothing
763 getDeclBinders new_name (InstD _) = returnRn Nothing
764 getDeclBinders new_name (RuleD _) = returnRn Nothing
767 getConFieldNames new_name (ConDecl con _ _ (RecCon fielddecls) src_loc : rest)
768 = mapRn (\n -> new_name n src_loc) (con:fields) `thenRn` \ cfs ->
769 getConFieldNames new_name rest `thenRn` \ ns ->
772 fields = concat (map fst fielddecls)
774 getConFieldNames new_name (ConDecl con _ _ condecl src_loc : rest)
775 = new_name con src_loc `thenRn` \ n ->
778 new_name f src_loc `thenRn` \ new_f ->
780 _ -> returnRn [n]) `thenRn` \ nn ->
781 getConFieldNames new_name rest `thenRn` \ ns ->
784 getConFieldNames new_name [] = returnRn []
786 getClassOpNames new_name (ClassOpSig op _ _ src_loc) = new_name op src_loc
789 @getDeclSysBinders@ gets the implicit binders introduced by a decl.
790 A the moment that's just the tycon and datacon that come with a class decl.
791 They aren'te returned by getDeclBinders because they aren't in scope;
792 but they *should* be put into the DeclsMap of this module.
794 Note that this excludes the default-method names of a class decl,
795 and the dict fun of an instance decl, because both of these have
796 bindings of their own elsewhere.
799 getDeclSysBinders new_name (TyClD (ClassDecl _ cname _ sigs _ _ tname dname snames src_loc))
800 = new_name dname src_loc `thenRn` \ datacon_name ->
801 new_name tname src_loc `thenRn` \ tycon_name ->
802 sequenceRn [new_name n src_loc | n <- snames] `thenRn` \ scsel_names ->
803 returnRn (tycon_name : datacon_name : scsel_names)
805 getDeclSysBinders new_name other_decl
809 %*********************************************************
811 \subsection{Reading an interface file}
813 %*********************************************************
816 findAndReadIface :: SDoc -> ModuleName -> WhereFrom
817 -> Bool -- Only relevant for SystemImport
818 -- True <=> Look for a .hi file
819 -- False <=> Look for .hi-boot file unless there's
820 -- a library .hi file
821 -> RnM d (Bool, Maybe (Module, ParsedIface))
822 -- Bool is True if the interface actually read was a .hi-boot one
823 -- Nothing <=> file not found, or unreadable, or illegible
824 -- Just x <=> successfully found and parsed
826 findAndReadIface doc_str mod_name from hi_file
827 = traceRn trace_msg `thenRn_`
828 -- we keep two maps for interface files,
829 -- one for 'normal' ones, the other for .hi-boot files,
830 -- hence the need to signal which kind we're interested.
832 getHiMaps `thenRn` \ hi_maps ->
834 case find_path from hi_maps of
836 (hi_boot, Just (fpath, mod)) -> traceRn (ptext SLIT("...reading from") <+> text fpath) `thenRn_`
837 readIface mod fpath `thenRn` \ result ->
838 returnRn (hi_boot, result)
839 (hi_boot, Nothing) -> traceRn (ptext SLIT("...not found")) `thenRn_`
840 returnRn (hi_boot, Nothing)
842 find_path ImportByUser (hi_map, _) = (False, lookupFM hi_map mod_name)
843 find_path ImportByUserSource (_, hiboot_map) = (True, lookupFM hiboot_map mod_name)
845 find_path ImportBySystem (hi_map, hiboot_map)
847 = -- If the module we seek is in our dependent set,
848 -- Look for a .hi file
849 (False, lookupFM hi_map mod_name)
852 -- Check if there's a library module of that name
853 -- If not, look for an hi-boot file
854 = case lookupFM hi_map mod_name of
855 stuff@(Just (_, mod)) | isLibModule mod -> (False, stuff)
856 other -> (True, lookupFM hiboot_map mod_name)
858 trace_msg = sep [hsep [ptext SLIT("Reading"),
860 ptext SLIT("interface for"),
861 pprModuleName mod_name <> semi],
862 nest 4 (ptext SLIT("reason:") <+> doc_str)]
865 @readIface@ tries just the one file.
868 readIface :: Module -> String -> RnM d (Maybe (Module, ParsedIface))
869 -- Nothing <=> file not found, or unreadable, or illegible
870 -- Just x <=> successfully found and parsed
871 readIface the_mod file_path
872 = ioToRnM (hGetStringBuffer False file_path) `thenRn` \ read_result ->
875 case parseIface contents
876 PState{ bol = 0#, atbol = 1#,
879 loc = mkSrcLoc (mkFastString file_path) 1 } of
880 PFailed err -> failWithRn Nothing err
881 POk _ (PIface mod_nm iface) ->
882 warnCheckRn (mod_nm == moduleName the_mod)
883 (hsep [ ptext SLIT("Something is amiss; requested module name")
885 , ptext SLIT("differs from name found in the interface file ")
886 , pprModuleName mod_nm
888 returnRn (Just (the_mod, iface))
891 | isDoesNotExistError err -> returnRn Nothing
892 | otherwise -> failWithRn Nothing (cannaeReadFile file_path err)
895 %*********************************************************
899 %*********************************************************
902 noIfaceErr filename boot_file
903 = hsep [ptext SLIT("Could not find valid"), boot,
904 ptext SLIT("interface file"), quotes (pprModule filename)]
906 boot | boot_file = ptext SLIT("[boot]")
909 cannaeReadFile file err
910 = hcat [ptext SLIT("Failed in reading file: "),
912 ptext SLIT("; error="),
916 = ptext SLIT("Failed to find interface decl for") <+> quotes (ppr name)
919 = sep [ptext SLIT("Failed to find (optional) interface decl for") <+> quotes (ppr name),
920 ptext SLIT("desired at") <+> ppr loc]
922 importDeclWarn mod name
923 = sep [ptext SLIT("Compiler tried to import decl from interface file with same name as module."),
924 ptext SLIT("(possible cause: module name clashes with interface file already in scope.)")
926 hsep [ptext SLIT("Interface:"), quotes (pprModuleName mod),
927 comma, ptext SLIT("name:"), quotes (ppr name)]
929 warnRedundantSourceImport mod_name
930 = ptext SLIT("Unnecessary {- SOURCE -} in the import of module") <+> quotes (pprModuleName mod_name)