%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[RnIfaces]{Cacheing and Renaming of Interfaces}
\begin{code}
-#include "HsVersions.h"
-
module RnIfaces (
- findHiFiles,
- cachedIface,
- cachedDecl,
- readIface,
- rnIfaces,
- finalIfaceInfo,
- IfaceCache(..),
- VersionInfo(..)
- ) where
+ getInterfaceExports,
+ getImportedInstDecls, getImportedRules,
+ lookupFixity, loadHomeInterface,
+ importDecl, recordSlurp,
+ getImportVersions, getSlurped,
-import Ubiq
+ checkUpToDate,
-import LibDirectory
-import PreludeGlaST ( thenPrimIO, seqPrimIO, readVar, writeVar, MutableVar(..) )
+ getDeclBinders, getDeclSysBinders,
+ removeContext -- removeContext probably belongs somewhere else
+ ) where
-import HsSyn
-import HsPragmas ( noGenPragmas )
-import RdrHsSyn
-import RnHsSyn
+#include "HsVersions.h"
+import CmdLineOpts ( opt_NoPruneDecls, opt_IgnoreIfacePragmas )
+import HsSyn ( HsDecl(..), TyClDecl(..), InstDecl(..), IfaceSig(..),
+ HsType(..), ConDecl(..), IE(..), ConDetails(..), Sig(..),
+ ForeignDecl(..), ForKind(..), isDynamicExtName,
+ FixitySig(..), RuleDecl(..),
+ isClassOpSig, Deprecation(..)
+ )
+import BasicTypes ( Version, NewOrData(..), defaultFixity )
+import RdrHsSyn ( RdrNameHsDecl, RdrNameInstDecl, RdrNameTyClDecl, RdrNameRuleDecl,
+ extractHsTyRdrNames, RdrNameDeprecation
+ )
+import RnEnv ( mkImportedGlobalName, newImportedBinder, mkImportedGlobalFromRdrName,
+ lookupOccRn, lookupImplicitOccRn,
+ pprAvail,
+ availName, availNames, addAvailToNameSet, addSysAvails,
+ FreeVars, emptyFVs
+ )
import RnMonad
-import RnSource ( rnTyDecl, rnClassDecl, rnInstDecl, rnPolyType )
-import RnUtils ( RnEnv(..), emptyRnEnv, lookupRnEnv, lookupTcRnEnv, extendGlobalRnEnv )
-import ParseIface ( parseIface )
-import ParseUtils ( ParsedIface(..), RdrIfaceDecl(..), RdrIfaceInst(..) )
-
-import Bag ( emptyBag, consBag, snocBag, unionBags, unionManyBags, isEmptyBag, bagToList )
-import CmdLineOpts ( opt_HiSuffix, opt_SysHiSuffix )
-import ErrUtils ( Error(..), Warning(..) )
-import FiniteMap ( emptyFM, lookupFM, addToFM, addToFM_C, plusFM, eltsFM,
- fmToList, delListFromFM, sizeFM, keysFM{-ToDo:rm-} )
-import Maybes ( maybeToBool )
-import Name ( moduleNamePair, origName, isRdrLexCon,
- RdrName(..){-instance NamedThing-}
+import RnHsSyn ( RenamedHsDecl, RenamedDeprecation )
+import ParseIface ( parseIface, IfaceStuff(..) )
+
+import FiniteMap ( FiniteMap, sizeFM, emptyFM, delFromFM, listToFM,
+ lookupFM, addToFM, addToFM_C, addListToFM,
+ fmToList, elemFM, foldFM
+ )
+import Name ( Name {-instance NamedThing-},
+ nameModule, isLocallyDefined,
+ isWiredInName, nameUnique, NamedThing(..)
+ )
+import Module ( Module, moduleString, pprModule,
+ mkVanillaModule, pprModuleName,
+ moduleUserString, moduleName, isLocalModule,
+ ModuleName, WhereFrom(..),
)
-import PprStyle -- ToDo:rm
-import Outputable -- ToDo:rm
-import PrelInfo ( builtinNameInfo )
-import Pretty
-import Maybes ( MaybeErr(..) )
-import UniqFM ( emptyUFM )
-import UniqSupply ( splitUniqSupply )
-import Util ( sortLt, removeDups, cmpPString, startsWith,
- panic, pprPanic, assertPanic, pprTrace{-ToDo:rm-} )
+import RdrName ( RdrName, rdrNameOcc )
+import NameSet
+import Var ( Id )
+import SrcLoc ( mkSrcLoc, SrcLoc )
+import PrelMods ( pREL_GHC )
+import PrelInfo ( cCallishTyKeys )
+import Bag
+import Maybes ( MaybeErr(..), maybeToBool, orElse )
+import ListSetOps ( unionLists )
+import Outputable
+import Unique ( Unique )
+import StringBuffer ( StringBuffer, hGetStringBuffer )
+import FastString ( mkFastString )
+import ErrUtils ( Message )
+import Lex
+import Outputable
+
+import IO ( isDoesNotExistError )
+import List ( nub )
\end{code}
+
+%*********************************************************
+%* *
+\subsection{Loading a new interface file}
+%* *
+%*********************************************************
+
\begin{code}
-type ModuleToIfaceContents = FiniteMap Module ParsedIface
-type ModuleToIfaceFilePath = FiniteMap Module FilePath
+loadHomeInterface :: SDoc -> Name -> RnM d Ifaces
+loadHomeInterface doc_str name
+ = loadInterface doc_str (moduleName (nameModule name)) ImportBySystem
+
+loadOrphanModules :: [ModuleName] -> RnM d ()
+loadOrphanModules mods
+ | null mods = returnRn ()
+ | otherwise = traceRn (text "Loading orphan modules:" <+>
+ fsep (map pprModuleName mods)) `thenRn_`
+ mapRn_ load mods `thenRn_`
+ returnRn ()
+ where
+ load mod = loadInterface (mk_doc mod) mod ImportBySystem
+ mk_doc mod = pprModuleName mod <+> ptext SLIT("is a orphan-instance module")
+
+
+loadInterface :: SDoc -> ModuleName -> WhereFrom -> RnM d Ifaces
+loadInterface doc mod from
+ = tryLoadInterface doc mod from `thenRn` \ (ifaces, maybe_err) ->
+ case maybe_err of
+ Nothing -> returnRn ifaces
+ Just err -> failWithRn ifaces err
+
+tryLoadInterface :: SDoc -> ModuleName -> WhereFrom -> RnM d (Ifaces, Maybe Message)
+ -- Returns (Just err) if an error happened
+ -- Guarantees to return with iImpModInfo m --> (... Just cts)
+ -- (If the load fails, we plug in a vanilla placeholder
+tryLoadInterface doc_str mod_name from
+ = getIfacesRn `thenRn` \ ifaces ->
+ let
+ mod_map = iImpModInfo ifaces
+ mod_info = lookupFM mod_map mod_name
+
+ hi_boot_file = case from of {
+ ImportByUser -> False ; -- Not hi-boot
+ ImportByUserSource -> True ; -- hi-boot
+ ImportBySystem ->
+ case mod_info of
+ Just (_, _, is_boot, _) -> is_boot
+
+ Nothing -> False
+ -- We're importing a module we know absolutely
+ -- nothing about, so we assume it's from
+ -- another package, where we aren't doing
+ -- dependency tracking. So it won't be a hi-boot file.
+ }
+ redundant_source_import
+ = case (from, mod_info) of
+ (ImportByUserSource, Just (_,_,False,_)) -> True
+ other -> False
+ in
+ -- CHECK WHETHER WE HAVE IT ALREADY
+ case mod_info of {
+ Just (_, _, _, Just _)
+ -> -- We're read it already so don't re-read it
+ returnRn (ifaces, Nothing) ;
+
+ _ ->
+
+ -- Issue a warning for a redundant {- SOURCE -} import
+ -- NB that we arrange to read all the ordinary imports before
+ -- any of the {- SOURCE -} imports
+ warnCheckRn (not redundant_source_import)
+ (warnRedundantSourceImport mod_name) `thenRn_`
+
+ -- READ THE MODULE IN
+ findAndReadIface doc_str mod_name hi_boot_file `thenRn` \ read_result ->
+ case read_result of {
+ Left err -> -- Not found, so add an empty export env to the Ifaces map
+ -- so that we don't look again
+ let
+ mod = mkVanillaModule mod_name
+ new_mod_map = addToFM mod_map mod_name (0, False, False, Just (mod, from, []))
+ new_ifaces = ifaces { iImpModInfo = new_mod_map }
+ in
+ setIfacesRn new_ifaces `thenRn_`
+ returnRn (new_ifaces, Just err) ;
+
+ -- Found and parsed!
+ Right iface ->
+
+ -- LOAD IT INTO Ifaces
+
+ -- NB: *first* we do loadDecl, so that the provenance of all the locally-defined
+ --- names is done correctly (notably, whether this is an .hi file or .hi-boot file).
+ -- If we do loadExport first the wrong info gets into the cache (unless we
+ -- explicitly tag each export which seems a bit of a bore)
+
+ getModuleRn `thenRn` \ this_mod_nm ->
+ let
+ rd_decls = pi_decls iface
+ mod = pi_mod iface
+ in
+ -- Sanity check. If we're system-importing a module we know nothing at all
+ -- about, it should be from a different package to this one
+ WARN( not (maybeToBool mod_info) &&
+ case from of { ImportBySystem -> True; other -> False } &&
+ isLocalModule mod,
+ ppr mod )
+ foldlRn (loadDecl mod) (iDecls ifaces) rd_decls `thenRn` \ new_decls ->
+ foldlRn (loadInstDecl mod) (iInsts ifaces) (pi_insts iface) `thenRn` \ new_insts ->
+ (if opt_IgnoreIfacePragmas
+ then returnRn emptyBag
+ else foldlRn (loadRule mod) (iRules ifaces) (pi_rules iface)) `thenRn` \ new_rules ->
+ (if opt_IgnoreIfacePragmas
+ then returnRn emptyNameEnv
+ else foldlRn (loadDeprec mod) (iDeprecs ifaces) (pi_deprecs iface)) `thenRn` \ new_deprecs ->
+ foldlRn (loadFixDecl mod_name) (iFixes ifaces) rd_decls `thenRn` \ new_fixities ->
+ mapRn (loadExport this_mod_nm) (pi_exports iface) `thenRn` \ avails_s ->
+ let
+ -- For an explicit user import, add to mod_map info about
+ -- the things the imported module depends on, extracted
+ -- from its usage info.
+ mod_map1 = case from of
+ ImportByUser -> addModDeps mod (pi_usages iface) mod_map
+ other -> mod_map
+
+ -- Now add info about this module
+ mod_map2 = addToFM mod_map1 mod_name mod_details
+ cts = (pi_mod iface, from, concat avails_s)
+ mod_details = (pi_vers iface, pi_orphan iface, hi_boot_file, Just cts)
+
+ new_ifaces = ifaces { iImpModInfo = mod_map2,
+ iDecls = new_decls,
+ iFixes = new_fixities,
+ iInsts = new_insts,
+ iRules = new_rules,
+ iDeprecs = new_deprecs }
+ in
+ setIfacesRn new_ifaces `thenRn_`
+ returnRn (new_ifaces, Nothing)
+ }}
+
+addModDeps :: Module -> [ImportVersion a]
+ -> ImportedModuleInfo -> ImportedModuleInfo
+-- (addModDeps M ivs deps)
+-- We are importing module M, and M.hi contains 'import' decls given by ivs
+addModDeps mod new_deps mod_deps
+ = foldr add mod_deps filtered_new_deps
+ where
+ -- Don't record dependencies when importing a module from another package
+ -- Except for its descendents which contain orphans,
+ -- and in that case, forget about the boot indicator
+ filtered_new_deps
+ | isLocalModule mod = [ (imp_mod, (version, has_orphans, is_boot, Nothing))
+ | (imp_mod, version, has_orphans, is_boot, _) <- new_deps
+ ]
+ | otherwise = [ (imp_mod, (version, True, False, Nothing))
+ | (imp_mod, version, has_orphans, _, _) <- new_deps,
+ has_orphans
+ ]
+ add (imp_mod, dep) deps = addToFM_C combine deps imp_mod dep
+
+ combine old@(_, _, old_is_boot, cts) new
+ | maybeToBool cts || not old_is_boot = old -- Keep the old info if it's already loaded
+ -- or if it's a non-boot pending load
+ | otherwise = new -- Otherwise pick new info
+
+loadExport :: ModuleName -> ExportItem -> RnM d [AvailInfo]
+loadExport this_mod (mod, entities)
+ | mod == this_mod = returnRn []
+ -- If the module exports anything defined in this module, just ignore it.
+ -- Reason: otherwise it looks as if there are two local definition sites
+ -- for the thing, and an error gets reported. Easiest thing is just to
+ -- filter them out up front. This situation only arises if a module
+ -- imports itself, or another module that imported it. (Necessarily,
+ -- this invoves a loop.) Consequence: if you say
+ -- module A where
+ -- import B( AType )
+ -- type AType = ...
+ --
+ -- module B( AType ) where
+ -- import {-# SOURCE #-} A( AType )
+ --
+ -- then you'll get a 'B does not export AType' message. A bit bogus
+ -- but it's a bogus thing to do!
+
+ | otherwise
+ = mapRn (load_entity mod) entities
+ where
+ new_name mod occ = mkImportedGlobalName mod occ
+
+ load_entity mod (Avail occ)
+ = new_name mod occ `thenRn` \ name ->
+ returnRn (Avail name)
+ load_entity mod (AvailTC occ occs)
+ = new_name mod occ `thenRn` \ name ->
+ mapRn (new_name mod) occs `thenRn` \ names ->
+ returnRn (AvailTC name names)
+
+
+loadFixDecl :: ModuleName -> FixityEnv
+ -> (Version, RdrNameHsDecl)
+ -> RnM d FixityEnv
+loadFixDecl mod_name fixity_env (version, FixD sig@(FixitySig rdr_name fixity loc))
+ = -- Ignore the version; when the fixity changes the version of
+ -- its 'host' entity changes, so we don't need a separate version
+ -- number for fixities
+ mkImportedGlobalName mod_name (rdrNameOcc rdr_name) `thenRn` \ name ->
+ let
+ new_fixity_env = addToNameEnv fixity_env name (FixitySig name fixity loc)
+ in
+ returnRn new_fixity_env
-type IfaceCache
- = MutableVar _RealWorld (ModuleToIfaceContents,
- ModuleToIfaceFilePath)
-\end{code}
+ -- Ignore the other sorts of decl
+loadFixDecl mod_name fixity_env other_decl = returnRn fixity_env
-*********************************************************
-* *
-\subsection{Looking for interface files}
-* *
-*********************************************************
+loadDecl :: Module
+ -> DeclsMap
+ -> (Version, RdrNameHsDecl)
+ -> RnM d DeclsMap
-Return a mapping from module-name to
-absolute-filename-for-that-interface.
-\begin{code}
-findHiFiles :: [FilePath] -> [FilePath] -> IO (FiniteMap Module FilePath)
+loadDecl mod decls_map (version, decl)
+ = getDeclBinders new_name decl `thenRn` \ maybe_avail ->
+ case maybe_avail of {
+ Nothing -> returnRn decls_map; -- No bindings
+ Just avail ->
-findHiFiles dirs sysdirs
- = hPutStr stderr " findHiFiles " >>
- do_dirs emptyFM (dirs ++ sysdirs) >>= \ result ->
- hPutStr stderr " done\n" >>
- return result
+ getDeclSysBinders new_name decl `thenRn` \ sys_bndrs ->
+ let
+ full_avail = addSysAvails avail sys_bndrs
+ -- Add the sys-binders to avail. When we import the decl,
+ -- it's full_avail that will get added to the 'already-slurped' set (iSlurp)
+ -- If we miss out sys-binders, we'll read the decl multiple times!
+
+ main_name = availName avail
+ new_decls_map = foldl add_decl decls_map
+ [ (name, (version, full_avail, name==main_name, (mod, decl')))
+ | name <- availNames full_avail]
+ add_decl decls_map (name, stuff)
+ = WARN( name `elemNameEnv` decls_map, ppr name )
+ addToNameEnv decls_map name stuff
+ in
+ returnRn new_decls_map
+ }
where
- do_dirs env [] = return env
- do_dirs env (dir:dirs)
- = do_dir env dir >>= \ new_env ->
- do_dirs new_env dirs
- -------
- do_dir env dir
- = hPutStr stderr "D" >>
- getDirectoryContents dir >>= \ entries ->
- do_entries env entries
- where
- do_entries env [] = return env
- do_entries env (e:es)
- = do_entry env e >>= \ new_env ->
- do_entries new_env es
- -------
- do_entry env e
- = case (acceptable_hi (reverse e)) of
- Nothing -> --trace ("Deemed uncool:"++e) $
- hPutStr stderr "." >>
- return env
- Just mod ->
- let
- pmod = _PK_ mod
- in
- case (lookupFM env pmod) of
- Nothing -> --trace ("Adding "++mod++" -> "++e) $
- hPutStr stderr "!" >>
- return (addToFM env pmod (dir ++ '/':e))
- -- ToDo: use DIR_SEP, not /
-
- Just xx -> ( if de_dot xx /= e then trace ("Already mapped!! "++mod++" -> "++xx++"; ignoring:"++e) else id) $
- hPutStr stderr "." >>
- return env
- -------
- acceptable_hi rev_e -- looking at pathname *backwards*
- = case (startsWith (reverse opt_HiSuffix) rev_e) of
- Nothing -> Nothing
- Just xs -> plausible_modname xs{-reversed-}
-
- -------
- de_dot ('.' : '/' : xs) = xs
- de_dot xs = xs
-
- -------
- plausible_modname rev_e
- = let
- cand = reverse (takeWhile is_modname_char rev_e)
- in
- if null cand || not (isUpper (head cand))
- then Nothing
- else Just cand
- where
- is_modname_char c = isAlphanum c || c == '_'
+ -- newImportedBinder puts into the cache the binder with the
+ -- module information set correctly. When the decl is later renamed,
+ -- the binding site will thereby get the correct module.
+ new_name rdr_name loc = newImportedBinder mod rdr_name
+
+ {-
+ If a signature decl is being loaded, and optIgnoreIfacePragmas is on,
+ we toss away unfolding information.
+
+ Also, if the signature is loaded from a module we're importing from source,
+ we do the same. This is to avoid situations when compiling a pair of mutually
+ recursive modules, peering at unfolding info in the interface file of the other,
+ e.g., you compile A, it looks at B's interface file and may as a result change
+ its interface file. Hence, B is recompiled, maybe changing its interface file,
+ which will the unfolding info used in A to become invalid. Simple way out is to
+ just ignore unfolding info.
+
+ [Jan 99: I junked the second test above. If we're importing from an hi-boot
+ file there isn't going to *be* any pragma info. Maybe the above comment
+ dates from a time where we picked up a .hi file first if it existed?]
+ -}
+ decl' = case decl of
+ SigD (IfaceSig name tp ls loc) | opt_IgnoreIfacePragmas
+ -> SigD (IfaceSig name tp [] loc)
+ other -> decl
+
+loadInstDecl :: Module
+ -> Bag GatedDecl
+ -> RdrNameInstDecl
+ -> RnM d (Bag GatedDecl)
+loadInstDecl mod insts decl@(InstDecl inst_ty binds uprags dfun_name src_loc)
+ =
+ -- Find out what type constructors and classes are "gates" for the
+ -- instance declaration. If all these "gates" are slurped in then
+ -- we should slurp the instance decl too.
+ --
+ -- We *don't* want to count names in the context part as gates, though.
+ -- For example:
+ -- instance Foo a => Baz (T a) where ...
+ --
+ -- Here the gates are Baz and T, but *not* Foo.
+ let
+ munged_inst_ty = removeContext inst_ty
+ free_names = extractHsTyRdrNames munged_inst_ty
+ in
+ setModuleRn (moduleName mod) $
+ mapRn mkImportedGlobalFromRdrName free_names `thenRn` \ gate_names ->
+ returnRn ((mkNameSet gate_names, (mod, InstD decl)) `consBag` insts)
+
+
+-- In interface files, the instance decls now look like
+-- forall a. Foo a -> Baz (T a)
+-- so we have to strip off function argument types as well
+-- as the bit before the '=>' (which is always empty in interface files)
+removeContext (HsForAllTy tvs cxt ty) = HsForAllTy tvs [] (removeFuns ty)
+removeContext ty = removeFuns ty
+
+removeFuns (MonoFunTy _ ty) = removeFuns ty
+removeFuns ty = ty
+
+
+loadRule :: Module -> Bag GatedDecl
+ -> RdrNameRuleDecl -> RnM d (Bag GatedDecl)
+-- "Gate" the rule simply by whether the rule variable is
+-- needed. We can refine this later.
+loadRule mod rules decl@(IfaceRuleDecl var body src_loc)
+ = setModuleRn (moduleName mod) $
+ mkImportedGlobalFromRdrName var `thenRn` \ var_name ->
+ returnRn ((unitNameSet var_name, (mod, RuleD decl)) `consBag` rules)
+
+-- SUP: TEMPORARY HACK, ignoring module deprecations for now
+loadDeprec :: Module -> DeprecationEnv -> RdrNameDeprecation -> RnM d DeprecationEnv
+loadDeprec mod deprec_env (Deprecation (IEModuleContents _) txt)
+ = traceRn (text "module deprecation not yet implemented:" <+> ppr mod <> colon <+> ppr txt) `thenRn_`
+ returnRn deprec_env
+loadDeprec mod deprec_env (Deprecation ie txt)
+ = setModuleRn (moduleName mod) $
+ mapRn mkImportedGlobalFromRdrName (namesFromIE ie) `thenRn` \ names ->
+ traceRn (text "loaded deprecation(s) for" <+> hcat (punctuate comma (map ppr names)) <> colon <+> ppr txt) `thenRn_`
+ returnRn (extendNameEnv deprec_env (zip names (repeat txt)))
+
+namesFromIE :: IE a -> [a]
+namesFromIE (IEVar n ) = [n]
+namesFromIE (IEThingAbs n ) = [n]
+namesFromIE (IEThingAll n ) = [n]
+namesFromIE (IEThingWith n ns) = n:ns
+namesFromIE (IEModuleContents _ ) = []
\end{code}
-*********************************************************
-* *
-\subsection{Reading interface files}
-* *
-*********************************************************
-Return cached info about a Module's interface; otherwise,
-read the interface (using our @ModuleToIfaceFilePath@ map
-to decide where to look).
+%********************************************************
+%* *
+\subsection{Loading usage information}
+%* *
+%********************************************************
\begin{code}
-cachedIface :: IfaceCache
- -> Module
- -> IO (MaybeErr ParsedIface Error)
-
-cachedIface iface_cache mod
- = readVar iface_cache `thenPrimIO` \ (iface_fm, file_fm) ->
-
- case (lookupFM iface_fm mod) of
- Just iface -> return (Succeeded iface)
- Nothing ->
- case (lookupFM file_fm mod) of
- Nothing -> return (Failed (noIfaceErr mod))
- Just file ->
- readIface file mod >>= \ read_iface ->
- case read_iface of
- Failed err -> -- pprTrace "module-file map:\n" (ppAboves [ppCat [ppPStr m, ppStr f] | (m,f) <- fmToList file_fm]) $
- return (Failed err)
- Succeeded iface ->
- let
- iface_fm' = addToFM iface_fm mod iface
- in
- writeVar iface_cache (iface_fm', file_fm) `seqPrimIO`
- return (Succeeded iface)
-
-----------
-cachedDecl :: IfaceCache
- -> Bool -- True <=> tycon or class name
- -> RdrName
- -> IO (MaybeErr RdrIfaceDecl Error)
-
--- ToDo: this is where the check for Prelude.map being
--- located in PreludeList.map should be done ...
-
-cachedDecl iface_cache class_or_tycon orig
- = cachedIface iface_cache mod >>= \ maybe_iface ->
- case maybe_iface of
- Failed err -> return (Failed err)
- Succeeded (ParsedIface _ _ _ _ exps _ _ tdefs vdefs _ _) ->
- case (lookupFM (if class_or_tycon then tdefs else vdefs) str) of
- Just decl -> return (Succeeded decl)
- Nothing -> return (Failed (noDeclInIfaceErr mod str))
+upToDate = True
+outOfDate = False
+
+checkUpToDate :: ModuleName -> RnMG Bool -- True <=> no need to recompile
+ -- When this guy is called, we already know that the
+ -- source code is unchanged from last time
+checkUpToDate mod_name
+ = getIfacesRn `thenRn` \ ifaces ->
+ findAndReadIface doc_str mod_name
+ False {- Not hi-boot -} `thenRn` \ read_result ->
+
+ -- CHECK WHETHER WE HAVE IT ALREADY
+ case read_result of
+ Left err -> -- Old interface file not found, or garbled, so we'd better bail out
+ traceRn (vcat [ptext SLIT("No old iface") <+> pprModuleName mod_name,
+ err]) `thenRn_`
+ returnRn outOfDate
+
+ Right iface
+ -> -- Found it, so now check it
+ checkModUsage (pi_usages iface)
where
- (mod, str) = moduleNamePair orig
-
-----------
-cachedDeclByType :: IfaceCache
- -> RnName{-NB: diff type than cachedDecl -}
- -> IO (MaybeErr RdrIfaceDecl Error)
-
-cachedDeclByType iface_cache rn
- -- the idea is: check that, e.g., if we're given an
- -- RnClass, then we really get back a ClassDecl from
- -- the cache (not an RnData, or something silly)
- = cachedDecl iface_cache (isRnTyConOrClass rn) (origName rn) >>= \ maybe_decl ->
+ -- Only look in current directory, with suffix .hi
+ doc_str = sep [ptext SLIT("need usage info from"), pprModuleName mod_name]
+
+checkModUsage [] = returnRn upToDate -- Yes! Everything is up to date!
+
+checkModUsage ((mod_name, old_mod_vers, _, _, Specifically []) : rest)
+ -- If CurrentModule.hi contains
+ -- import Foo :: ;
+ -- then that simply records that Foo lies below CurrentModule in the
+ -- hierarchy, but CurrentModule doesn't depend in any way on Foo.
+ -- In this case we don't even want to open Foo's interface.
+ = traceRn (ptext SLIT("Nothing used from:") <+> ppr mod_name) `thenRn_`
+ checkModUsage rest -- This one's ok, so check the rest
+
+checkModUsage ((mod_name, old_mod_vers, _, _, whats_imported) : rest)
+ = tryLoadInterface doc_str mod_name ImportBySystem `thenRn` \ (ifaces, maybe_err) ->
+ case maybe_err of {
+ Just err -> traceRn (sep [ptext SLIT("Can't find version number for module"),
+ pprModuleName mod_name]) `thenRn_`
+ returnRn outOfDate ;
+ -- Couldn't find or parse a module mentioned in the
+ -- old interface file. Don't complain -- it might just be that
+ -- the current module doesn't need that import and it's been deleted
+ Nothing ->
let
- return_maybe_decl = return maybe_decl
- return_failed msg = return (Failed msg)
+ new_mod_vers = case lookupFM (iImpModInfo ifaces) mod_name of
+ Just (version, _, _, _) -> version
in
- case maybe_decl of
- Failed _ -> return_maybe_decl
- Succeeded if_decl ->
- case rn of
- WiredInId _ -> return_failed (ifaceLookupWiredErr "value" rn)
- WiredInTyCon _ -> return_failed (ifaceLookupWiredErr "type constructor" rn)
- RnUnbound _ -> pprPanic "cachedDeclByType:" (ppr PprDebug rn)
-
- RnSyn _ -> return_maybe_decl
- RnData _ _ _ -> return_maybe_decl
- RnImplicitTyCon _ -> if is_tycon_decl if_decl
- then return_maybe_decl
- else return_failed (badIfaceLookupErr "type constructor" rn if_decl)
-
- RnClass _ _ -> return_maybe_decl
- RnImplicitClass _ -> if is_class_decl if_decl
- then return_maybe_decl
- else return_failed (badIfaceLookupErr "class" rn if_decl)
-
- RnName _ -> return_maybe_decl
- RnConstr _ _ -> return_maybe_decl
- RnField _ _ -> return_maybe_decl
- RnClassOp _ _ -> return_maybe_decl
- RnImplicit _ -> if is_val_decl if_decl
- then return_maybe_decl
- else return_failed (badIfaceLookupErr "value" rn if_decl)
+ -- If the module version hasn't changed, just move on
+ if new_mod_vers == old_mod_vers then
+ traceRn (sep [ptext SLIT("Module version unchanged:"), pprModuleName mod_name])
+ `thenRn_` checkModUsage rest
+ else
+ traceRn (sep [ptext SLIT("Module version has changed:"), pprModuleName mod_name])
+ `thenRn_`
+ -- Module version changed, so check entities inside
+
+ -- If the usage info wants to say "I imported everything from this module"
+ -- it does so by making whats_imported equal to Everything
+ -- In that case, we must recompile
+ case whats_imported of {
+ Everything -> traceRn (ptext SLIT("...and I needed the whole module")) `thenRn_`
+ returnRn outOfDate; -- Bale out
+
+ Specifically old_local_vers ->
+
+ -- Non-empty usage list, so check item by item
+ checkEntityUsage mod_name (iDecls ifaces) old_local_vers `thenRn` \ up_to_date ->
+ if up_to_date then
+ traceRn (ptext SLIT("...but the bits I use haven't.")) `thenRn_`
+ checkModUsage rest -- This one's ok, so check the rest
+ else
+ returnRn outOfDate -- This one failed, so just bail out now
+ }}
where
- is_tycon_decl (TypeSig _ _ _) = True
- is_tycon_decl (NewTypeSig _ _ _ _) = True
- is_tycon_decl (DataSig _ _ _ _ _) = True
- is_tycon_decl _ = False
-
- is_class_decl (ClassSig _ _ _ _) = True
- is_class_decl _ = False
-
- is_val_decl (ValSig _ _ _) = True
- is_val_decl (DataSig _ _ _ _ _) = True -- may be a constr or field
- is_val_decl (NewTypeSig _ _ _ _) = True -- may be a constr
- is_val_decl (ClassSig _ _ _ _) = True -- may be a method
- is_val_decl _ = False
-\end{code}
+ doc_str = sep [ptext SLIT("need version info for"), pprModuleName mod_name]
-\begin{code}
-readIface :: FilePath -> Module
- -> IO (MaybeErr ParsedIface Error)
-readIface file mod
- = hPutStr stderr (" reading "++file) >>
- readFile file `thenPrimIO` \ read_result ->
- case read_result of
- Left err -> return (Failed (cannaeReadErr file err))
- Right contents -> hPutStr stderr " parsing" >>
- let parsed = parseIface contents in
- hPutStr stderr " done\n" >>
- return parsed
+checkEntityUsage mod decls []
+ = returnRn upToDate -- Yes! All up to date!
+
+checkEntityUsage mod decls ((occ_name,old_vers) : rest)
+ = mkImportedGlobalName mod occ_name `thenRn` \ name ->
+ case lookupNameEnv decls name of
+
+ Nothing -> -- We used it before, but it ain't there now
+ traceRn (sep [ptext SLIT("No longer exported:"), ppr name])
+ `thenRn_` returnRn outOfDate
+
+ Just (new_vers,_,_,_) -- It's there, but is it up to date?
+ | new_vers == old_vers
+ -- Up to date, so check the rest
+ -> checkEntityUsage mod decls rest
+
+ | otherwise
+ -- Out of date, so bale out
+ -> traceRn (sep [ptext SLIT("Out of date:"), ppr name]) `thenRn_`
+ returnRn outOfDate
\end{code}
+%*********************************************************
+%* *
+\subsection{Getting in a declaration}
+%* *
+%*********************************************************
+
\begin{code}
-rnIfaces :: IfaceCache -- iface cache (mutvar)
- -> [Module] -- directly imported modules
- -> UniqSupply
- -> RnEnv -- defined (in the source) name env
- -> RnEnv -- mentioned (in the source) name env
- -> RenamedHsModule -- module to extend with iface decls
- -> [RnName] -- imported names required (really the
- -- same info as in mentioned name env)
- -- Also, all the things we may look up
- -- later by key (Unique).
- -> IO (RenamedHsModule, -- extended module
- RnEnv, -- final env (for renaming derivings)
- ImplicitEnv, -- implicit names used (for usage info)
- (Bag Error, Bag Warning))
-
-rnIfaces iface_cache imp_mods us
- def_env@((dqual, dunqual, dtc_qual, dtc_unqual), dstack)
- occ_env@((qual, unqual, tc_qual, tc_unqual), stack)
- rn_module@(HsModule modname iface_version exports imports fixities
- typedecls typesigs classdecls instdecls instsigs
- defdecls binds sigs src_loc)
- todo
- = {-
- pprTrace "rnIfaces:going after:" (ppCat (map (ppr PprDebug) todo)) $
-
- pprTrace "rnIfaces:qual:" (ppCat [ppBesides[ppPStr m,ppChar '.',ppPStr n] | (m,n) <- keysFM qual]) $
- pprTrace "rnIfaces:unqual:" (ppCat (map ppPStr (keysFM unqual))) $
- pprTrace "rnIfaces:tc_qual:" (ppCat [ppBesides[ppPStr m,ppChar '.',ppPStr n] | (m,n) <- keysFM tc_qual]) $
- pprTrace "rnIfaces:tc_unqual:" (ppCat (map ppPStr (keysFM tc_unqual))) $
-
- pprTrace "rnIfaces:dqual:" (ppCat [ppBesides[ppPStr m,ppChar '.',ppPStr n] | (m,n) <- keysFM dqual]) $
- pprTrace "rnIfaces:dunqual:" (ppCat (map ppPStr (keysFM dunqual))) $
- pprTrace "rnIfaces:dtc_qual:" (ppCat [ppBesides[ppPStr m,ppChar '.',ppPStr n] | (m,n) <- keysFM dtc_qual]) $
- pprTrace "rnIfaces:dtc_unqual:"(ppCat (map ppPStr (keysFM dtc_unqual))) $
- -}
+importDecl :: Name -> RnMG (Maybe (Module, RdrNameHsDecl))
+ -- Returns Nothing for
+ -- (a) wired in name
+ -- (b) local decl
+ -- (c) already slurped
+
+importDecl name
+ | isWiredInName name
+ = returnRn Nothing
+ | otherwise
+ = getSlurped `thenRn` \ already_slurped ->
+ if name `elemNameSet` already_slurped then
+ returnRn Nothing -- Already dealt with
+ else
+ if isLocallyDefined name then -- Don't bring in decls from
+ -- the renamed module's own interface file
+ addWarnRn (importDeclWarn name) `thenRn_`
+ returnRn Nothing
+ else
+ getNonWiredInDecl name
+\end{code}
- -- do transitive closure to bring in all needed names/defns and insts:
-
- decls_and_insts todo def_env occ_env empty_return us
- >>= \ (((if_typedecls, if_classdecls, if_instdecls, if_sigs),
- if_implicits,
- if_errs_warns),
- if_final_env) ->
-
- return (HsModule modname iface_version exports imports fixities
- (typedecls ++ if_typedecls)
- typesigs
- (classdecls ++ if_classdecls)
- (instdecls ++ if_instdecls)
- instsigs defdecls binds
- (sigs ++ if_sigs)
- src_loc,
- if_final_env,
- if_implicits,
- if_errs_warns)
+\begin{code}
+getNonWiredInDecl :: Name -> RnMG (Maybe (Module, RdrNameHsDecl))
+getNonWiredInDecl needed_name
+ = traceRn doc_str `thenRn_`
+ loadHomeInterface doc_str needed_name `thenRn` \ ifaces ->
+ case lookupNameEnv (iDecls ifaces) needed_name of
+
+ Just (version,avail,_,decl)
+ -> recordSlurp (Just version) avail `thenRn_`
+ returnRn (Just decl)
+
+ Nothing -- Can happen legitimately for "Optional" occurrences
+ -> addErrRn (getDeclErr needed_name) `thenRn_`
+ returnRn Nothing
where
- decls_and_insts todo def_env occ_env to_return us
- = do_decls todo -- initial batch of names to process
- (def_env, occ_env, us1) -- init stuff down
- to_return -- acc results
- >>= \ (decls_return,
- decls_def_env,
- decls_occ_env) ->
-
- cacheInstModules iface_cache imp_mods >>= \ errs ->
-
- do_insts decls_def_env decls_occ_env emptyRnEnv emptyFM
- (add_errs errs decls_return) us2
- where
- (us1,us2) = splitUniqSupply us
-
- do_insts def_env occ_env prev_env done_insts to_return us
- | size_tc_env occ_env == size_tc_env prev_env
- = return (to_return, occ_env)
-
- | otherwise
- = rnIfaceInstStuff iface_cache modname us1 occ_env done_insts to_return
- >>= \ (insts_return,
- new_insts,
- insts_occ_env,
- new_unknowns) ->
-
- do_decls new_unknowns -- new batch of names to process
- (def_env, insts_occ_env, us2) -- init stuff down
- insts_return -- acc results
- >>= \ (decls_return,
- decls_def_env,
- decls_occ_env) ->
-
- do_insts decls_def_env decls_occ_env occ_env new_insts decls_return us3
- where
- (us1,us') = splitUniqSupply us
- (us2,us3) = splitUniqSupply us'
-
- size_tc_env ((_, _, qual, unqual), _)
- = sizeFM qual + sizeFM unqual
-
-
- do_decls :: [RnName] -- Names we're looking for; we keep adding/deleting
- -- from this list; we're done when empty (nothing
- -- more needs to be looked for)
- -> Go_Down -- see defn below
- -> To_Return -- accumulated result
- -> IO (To_Return,
- RnEnv, -- extended decl env
- RnEnv) -- extended occ env
-
- do_decls to_find@[] down to_return
- = return (to_return, defenv down, occenv down)
-
- do_decls to_find@(n:ns) down to_return
- = case (lookup_defd down n) of
- Just _ -> -- previous processing must've found the stuff for this name;
- -- continue with the rest:
- -- pprTrace "do_decls:done:" (ppr PprDebug n) $
- do_decls ns down to_return
-
- Nothing -> -- OK, see what the cache has for us...
-
- cachedDeclByType iface_cache n >>= \ maybe_ans ->
- case maybe_ans of
- Failed err -> -- add the error, but keep going:
- -- pprTrace "do_decls:cache error:" (ppr PprDebug n) $
- do_decls ns down (add_err err to_return)
-
- Succeeded iface_decl -> -- something needing renaming!
- let
- (us1, us2) = splitUniqSupply (uniqsupply down)
- in
- case (initRn False{-iface-} modname (occenv down) us1 (
- setExtraRn emptyUFM{-no fixities-} $
- rnIfaceDecl iface_decl)) of {
- ((if_decl, if_defd, if_implicits), if_errs, if_warns) ->
- let
- new_unknowns = eltsFM (fst if_implicits) ++ eltsFM (snd if_implicits)
- in
- {-
- pprTrace "do_decls:renamed:" (ppAboves [ppr PprDebug n
- , ppCat [ppStr "new unknowns:", interpp'SP PprDebug new_unknowns]
- , ppCat [ppStr "defd vals:", interpp'SP PprDebug [n | (_,n) <- fst if_defd] ]
- , ppCat [ppStr "defd tcs:", interpp'SP PprDebug [n | (_,n) <- snd if_defd] ]
- ]) $
- -}
- do_decls (new_unknowns ++ ns)
- (add_occs if_defd if_implicits $
- new_uniqsupply us2 down)
- (add_decl if_decl $
- add_implicits if_implicits $
- add_errs if_errs $
- add_warns if_warns to_return)
- }
-
------------
-type Go_Down = (RnEnv, -- stuff we already have defns for;
- -- to check quickly if we've already
- -- found something for the name under consideration,
- -- due to previous processing.
- -- It starts off just w/ the defns for
- -- the things in this module.
- RnEnv, -- occurrence env; this gets added to as
- -- we process new iface decls. It includes
- -- entries for *all* occurrences, including those
- -- for which we have definitions.
- UniqSupply -- the obvious
- )
-
-lookup_defd (def_env, _, _) n
- | isRnTyConOrClass n
- = lookupTcRnEnv def_env (origName n)
- | otherwise
- = lookupRnEnv def_env (origName n)
-
-defenv (def_env, _, _) = def_env
-occenv (_, occ_env, _) = occ_env
-uniqsupply (_, _, us) = us
-
-new_uniqsupply us (def_env, occ_env, _) = (def_env, occ_env, us)
-
-add_occs (val_defds, tc_defds) (val_imps, tc_imps) (def_env, occ_env, us)
- = case (extendGlobalRnEnv def_env val_defds tc_defds) of { (new_def_env, def_dups) ->
- ASSERT(isEmptyBag def_dups)
- let
- val_occs = val_defds ++ fmToList val_imps
- tc_occs = tc_defds ++ fmToList tc_imps
- in
- case (extendGlobalRnEnv occ_env val_occs tc_occs) of { (new_occ_env, occ_dups) ->
+ doc_str = ptext SLIT("need decl for") <+> ppr needed_name
+\end{code}
--- ASSERT(isEmptyBag occ_dups)
--- False because we may get a dup on the name we just shoved in
+@getWiredInDecl@ maps a wired-in @Name@ to what it makes available.
+It behaves exactly as if the wired in decl were actually in an interface file.
+Specifically,
+\begin{itemize}
+\item if the wired-in name is a data type constructor or a data constructor,
+ it brings in the type constructor and all the data constructors; and
+ marks as ``occurrences'' any free vars of the data con.
- (new_def_env, new_occ_env, us) }}
+\item similarly for synonum type constructor
-----------------
-type To_Return = (([RenamedTyDecl], [RenamedClassDecl], [RenamedInstDecl], [RenamedSig]),
- ImplicitEnv, -- new names used implicitly
- (Bag Error, Bag Warning)
- )
+\item if the wired-in name is another wired-in Id, it marks as ``occurrences''
+ the free vars of the Id's type.
-empty_return :: To_Return
-empty_return = (([],[],[],[]), emptyImplicitEnv, (emptyBag,emptyBag))
+\item it loads the interface file for the wired-in thing for the
+ sole purpose of making sure that its instance declarations are available
+\end{itemize}
+All this is necessary so that we know all types that are ``in play'', so
+that we know just what instances to bring into scope.
+
-add_decl decl ((tydecls, classdecls, instdecls, sigs), implicit, msgs)
- = case decl of
- AddedTy t -> ((t:tydecls, classdecls, instdecls, sigs), implicit, msgs)
- AddedClass c -> ((tydecls, c:classdecls, instdecls, sigs), implicit, msgs)
- AddedSig s -> ((tydecls, classdecls, instdecls, s:sigs), implicit, msgs)
-add_insts is ((tydecls, classdecls, instdecls, sigs), implicit, msgs)
- = ((tydecls, classdecls, is ++ instdecls, sigs), implicit, msgs)
+
+%*********************************************************
+%* *
+\subsection{Getting what a module exports}
+%* *
+%*********************************************************
-add_implicits (val_imps, tc_imps) (decls, (val_fm, tc_fm), msgs)
- = (decls, (val_fm `plusFM` val_imps, tc_fm `plusFM` tc_imps), msgs)
+@getInterfaceExports@ is called only for directly-imported modules.
-add_err err (decls,implicit,(errs,warns)) = (decls,implicit,(errs `snocBag` err,warns))
-add_errs ers (decls,implicit,(errs,warns)) = (decls,implicit,(errs `unionBags` ers,warns))
-add_warns ws (decls,implicit,(errs,warns)) = (decls,implicit,(errs, warns `unionBags` ws))
+\begin{code}
+getInterfaceExports :: ModuleName -> WhereFrom -> RnMG (Module, Avails)
+getInterfaceExports mod_name from
+ = loadInterface doc_str mod_name from `thenRn` \ ifaces ->
+ case lookupFM (iImpModInfo ifaces) mod_name of
+ Just (_, _, _, Just (mod, _, avails)) -> returnRn (mod, avails)
+ -- loadInterface always puts something in the map
+ -- even if it's a fake
+ where
+ doc_str = sep [pprModuleName mod_name, ptext SLIT("is directly imported")]
\end{code}
+
+%*********************************************************
+%* *
+\subsection{Instance declarations are handled specially}
+%* *
+%*********************************************************
+
\begin{code}
-data AddedDecl -- purely local
- = AddedTy RenamedTyDecl
- | AddedClass RenamedClassDecl
- | AddedSig RenamedSig
-
-rnIfaceDecl :: RdrIfaceDecl
- -> RnM_Fixes _RealWorld
- (AddedDecl, -- the resulting decl to add to the pot
- ([(RdrName,RnName)], [(RdrName,RnName)]),
- -- new val/tycon-class names that have
- -- *been defined* while processing this decl
- ImplicitEnv -- new implicit val/tycon-class names that we
- -- stumbled into
- )
-
-rnIfaceDecl (TypeSig tc _ decl)
- = rnTyDecl decl `thenRn` \ rn_decl ->
- lookupTyCon tc `thenRn` \ rn_tc ->
- getImplicitUpRn `thenRn` \ mentioned ->
+getImportedInstDecls :: NameSet -> RnMG [(Module,RdrNameHsDecl)]
+getImportedInstDecls gates
+ = -- First, load any orphan-instance modules that aren't aready loaded
+ -- Orphan-instance modules are recorded in the module dependecnies
+ getIfacesRn `thenRn` \ ifaces ->
let
- defds = ([], [(tc, rn_tc)])
- implicits = mentioned `sub` defds
+ orphan_mods =
+ [mod | (mod, (_, True, _, Nothing)) <- fmToList (iImpModInfo ifaces)]
in
- returnRn (AddedTy rn_decl, defds, implicits)
+ loadOrphanModules orphan_mods `thenRn_`
-rnIfaceDecl (NewTypeSig tc dc _ decl)
- = rnTyDecl decl `thenRn` \ rn_decl ->
- lookupTyCon tc `thenRn` \ rn_tc ->
- lookupValue dc `thenRn` \ rn_dc ->
- getImplicitUpRn `thenRn` \ mentioned ->
+ -- Now we're ready to grab the instance declarations
+ -- Find the un-gated ones and return them,
+ -- removing them from the bag kept in Ifaces
+ getIfacesRn `thenRn` \ ifaces ->
let
- defds = ([(dc, rn_dc)], [(tc, rn_tc)])
- implicits = mentioned `sub` defds
+ (decls, new_insts) = selectGated gates (iInsts ifaces)
in
- returnRn (AddedTy rn_decl, defds, implicits)
-
-rnIfaceDecl (DataSig tc dcs fcs _ decl)
- = rnTyDecl decl `thenRn` \ rn_decl ->
- lookupTyCon tc `thenRn` \ rn_tc ->
- mapRn lookupValue dcs `thenRn` \ rn_dcs ->
- mapRn lookupValue fcs `thenRn` \ rn_fcs ->
- getImplicitUpRn `thenRn` \ mentioned ->
+ setIfacesRn (ifaces { iInsts = new_insts }) `thenRn_`
+
+ traceRn (sep [text "getImportedInstDecls:",
+ nest 4 (fsep (map ppr gate_list)),
+ text "Slurped" <+> int (length decls) <+> text "instance declarations",
+ nest 4 (vcat (map ppr_brief_inst_decl decls))]) `thenRn_`
+ returnRn decls
+ where
+ gate_list = nameSetToList gates
+
+ppr_brief_inst_decl (mod, InstD (InstDecl inst_ty _ _ _ _))
+ = case inst_ty of
+ HsForAllTy _ _ tau -> ppr tau
+ other -> ppr inst_ty
+
+getImportedRules :: RnMG [(Module,RdrNameHsDecl)]
+getImportedRules
+ | opt_IgnoreIfacePragmas = returnRn []
+ | otherwise
+ = getIfacesRn `thenRn` \ ifaces ->
let
- defds = (zip dcs rn_dcs ++ zip fcs rn_fcs , [(tc, rn_tc)])
- implicits = mentioned `sub` defds
+ gates = iSlurp ifaces -- Anything at all that's been slurped
+ (decls, new_rules) = selectGated gates (iRules ifaces)
in
- returnRn (AddedTy rn_decl, defds, implicits)
+ setIfacesRn (ifaces { iRules = new_rules }) `thenRn_`
+ traceRn (sep [text "getImportedRules:",
+ text "Slurped" <+> int (length decls) <+> text "rules"]) `thenRn_`
+ returnRn decls
+
+selectGated gates decl_bag
+ -- Select only those decls whose gates are *all* in 'gates'
+#ifdef DEBUG
+ | opt_NoPruneDecls -- Just to try the effect of not gating at all
+ = (foldrBag (\ (_,d) ds -> d:ds) [] decl_bag, emptyBag) -- Grab them all
+
+ | otherwise
+#endif
+ = foldrBag select ([], emptyBag) decl_bag
+ where
+ select (reqd, decl) (yes, no)
+ | isEmptyNameSet (reqd `minusNameSet` gates) = (decl:yes, no)
+ | otherwise = (yes, (reqd,decl) `consBag` no)
+
+lookupFixity :: Name -> RnMS Fixity
+lookupFixity name
+ | isLocallyDefined name
+ = getFixityEnv `thenRn` \ local_fix_env ->
+ case lookupNameEnv local_fix_env name of
+ Just (FixitySig _ fix _) -> returnRn fix
+ Nothing -> returnRn defaultFixity
+
+ | otherwise -- Imported
+ -- For imported names, we have to get their fixities by doing a loadHomeInterface,
+ -- and consulting the Ifaces that comes back from that, because the interface
+ -- file for the Name might not have been loaded yet. Why not? Suppose you import module A,
+ -- which exports a function 'f', which is defined in module B. Then B isn't loaded
+ -- right away (after all, it's possible that nothing from B will be used).
+ -- When we come across a use of 'f', we need to know its fixity, and it's then,
+ -- and only then, that we load B.hi. That is what's happening here.
+ = loadHomeInterface doc name `thenRn` \ ifaces ->
+ case lookupNameEnv (iFixes ifaces) name of
+ Just (FixitySig _ fix _) -> returnRn fix
+ Nothing -> returnRn defaultFixity
+ where
+ doc = ptext SLIT("Checking fixity for") <+> ppr name
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Keeping track of what we've slurped, and version numbers}
+%* *
+%*********************************************************
+
+getImportVersions figures out what the ``usage information'' for this
+moudule is; that is, what it must record in its interface file as the
+things it uses. It records:
+
+\begin{itemize}
+\item (a) anything reachable from its body code
+\item (b) any module exported with a @module Foo@
+\item (c) anything reachable from an exported item
+\end{itemize}
+
+Why (b)? Because if @Foo@ changes then this module's export list
+will change, so we must recompile this module at least as far as
+making a new interface file --- but in practice that means complete
+recompilation.
+
+Why (c)? Consider this:
+\begin{verbatim}
+ module A( f, g ) where | module B( f ) where
+ import B( f ) | f = h 3
+ g = ... | h = ...
+\end{verbatim}
+
+Here, @B.f@ isn't used in A. Should we nevertheless record @B.f@ in
+@A@'s usages? Our idea is that we aren't going to touch A.hi if it is
+*identical* to what it was before. If anything about @B.f@ changes
+than anyone who imports @A@ should be recompiled in case they use
+@B.f@ (they'll get an early exit if they don't). So, if anything
+about @B.f@ changes we'd better make sure that something in A.hi
+changes, and the convenient way to do that is to record the version
+number @B.f@ in A.hi in the usage list. If B.f changes that'll force a
+complete recompiation of A, which is overkill but it's the only way to
+write a new, slightly different, A.hi.
+
+But the example is tricker. Even if @B.f@ doesn't change at all,
+@B.h@ may do so, and this change may not be reflected in @f@'s version
+number. But with -O, a module that imports A must be recompiled if
+@B.h@ changes! So A must record a dependency on @B.h@. So we treat
+the occurrence of @B.f@ in the export list *just as if* it were in the
+code of A, and thereby haul in all the stuff reachable from it.
+
+[NB: If B was compiled with -O, but A isn't, we should really *still*
+haul in all the unfoldings for B, in case the module that imports A *is*
+compiled with -O. I think this is the case.]
+
+Even if B is used at all we get a usage line for B
+ import B <n> :: ... ;
+in A.hi, to record the fact that A does import B. This is used to decide
+to look to look for B.hi rather than B.hi-boot when compiling a module that
+imports A. This line says that A imports B, but uses nothing in it.
+So we'll get an early bale-out when compiling A if B's version changes.
-rnIfaceDecl (ClassSig clas ops _ decl)
- = rnClassDecl decl `thenRn` \ rn_decl ->
- lookupClass clas `thenRn` \ rn_clas ->
- mapRn (lookupClassOp rn_clas) ops `thenRn` \ rn_ops ->
- getImplicitUpRn `thenRn` \ mentioned ->
+\begin{code}
+getImportVersions :: ModuleName -- Name of this module
+ -> ExportEnv -- Info about exports
+ -> RnMG (VersionInfo Name) -- Version info for these names
+
+getImportVersions this_mod (ExportEnv _ _ export_all_mods)
+ = getIfacesRn `thenRn` \ ifaces ->
let
- defds = (ops `zip` rn_ops, [(clas, rn_clas)])
- implicits = mentioned `sub` defds
+ mod_map = iImpModInfo ifaces
+ imp_names = iVSlurp ifaces
+
+ -- mv_map groups together all the things imported from a particular module.
+ mv_map :: FiniteMap ModuleName [(Name,Version)]
+ mv_map = foldr add_mv emptyFM imp_names
+
+ -- Build the result list by adding info for each module.
+ -- For (a) a library module, we don't record it at all unless it contains orphans
+ -- (We must never lose track of orphans.)
+ --
+ -- (b) a source-imported module, don't record the dependency at all
+ --
+ -- (b) may seem a bit strange. The idea is that the usages in a .hi file records
+ -- *all* the module's dependencies other than the loop-breakers. We use
+ -- this info in findAndReadInterface to decide whether to look for a .hi file or
+ -- a .hi-boot file.
+ --
+ -- This means we won't track version changes, or orphans, from .hi-boot files.
+ -- The former is potentially rather bad news. It could be fixed by recording
+ -- whether something is a boot file along with the usage info for it, but
+ -- I can't be bothered just now.
+
+ mk_version_info mod_name (version, has_orphans, is_boot, contents) so_far
+ | mod_name == this_mod -- Check if M appears in the set of modules 'below' M
+ -- This seems like a convenient place to check
+ = WARN( not is_boot, ptext SLIT("Wierd:") <+> ppr this_mod <+>
+ ptext SLIT("imports itself (perhaps indirectly)") )
+ so_far
+
+ | otherwise
+ = let
+ go_for_it exports = (mod_name, version, has_orphans, is_boot, exports)
+ : so_far
+ in
+ case contents of
+ Nothing -> -- We didn't even open the interface
+ -- This happens when a module, Foo, that we explicitly imported has
+ -- 'import Baz' in its interface file, recording that Baz is below
+ -- Foo in the module dependency hierarchy. We want to propagate this
+ -- information. The Nothing says that we didn't even open the interface
+ -- file but we must still propagate the dependeny info.
+ -- The module in question must be a local module (in the same package)
+ go_for_it (Specifically [])
+
+ Just (mod, how_imported, _)
+ | is_sys_import && is_lib_module && not has_orphans
+ -> so_far
+
+ | is_lib_module -- Record the module but not detailed
+ || mod_name `elem` export_all_mods -- version information for the imports
+ -> go_for_it Everything
+
+ | otherwise
+ -> case lookupFM mv_map mod_name of
+ Just whats_imported -> go_for_it (Specifically whats_imported)
+ Nothing -> go_for_it (Specifically [])
+ -- This happens if you have
+ -- import Foo
+ -- but don't actually *use* anything from Foo
+ -- In which case record an empty dependency list
+ where
+ is_lib_module = not (isLocalModule mod)
+ is_sys_import = case how_imported of
+ ImportBySystem -> True
+ other -> False
+
in
- returnRn (AddedClass rn_decl, defds, implicits)
-
-rnIfaceDecl (ValSig f src_loc ty)
- -- should rename_sig in RnBinds be used here? ToDo
- = lookupValue f `thenRn` \ rn_f ->
- -- pprTrace "rnIfaceDecl:ValSig:" (ppr PprDebug ty) $
- rnPolyType nullTyVarNamesEnv ty `thenRn` \ rn_ty ->
- getImplicitUpRn `thenRn` \ mentioned ->
+
+ returnRn (foldFM mk_version_info [] mod_map)
+ where
+ add_mv v@(name, version) mv_map
+ = addToFM_C add_item mv_map mod [v]
+ where
+ mod = moduleName (nameModule name)
+ add_item vs _ = (v:vs)
+\end{code}
+
+\begin{code}
+getSlurped
+ = getIfacesRn `thenRn` \ ifaces ->
+ returnRn (iSlurp ifaces)
+
+recordSlurp maybe_version avail
+-- Nothing for locally defined names
+-- Just version for imported names
+ = getIfacesRn `thenRn` \ ifaces@(Ifaces { iSlurp = slurped_names,
+ iVSlurp = imp_names }) ->
let
- defds = ([(f, rn_f)], [])
- implicits = mentioned `sub` defds
+ new_slurped_names = addAvailToNameSet slurped_names avail
+
+ new_imp_names = case maybe_version of
+ Just version -> (availName avail, version) : imp_names
+ Nothing -> imp_names
in
- returnRn (AddedSig (Sig rn_f rn_ty noGenPragmas src_loc), defds, implicits)
+ setIfacesRn (ifaces { iSlurp = new_slurped_names,
+ iVSlurp = new_imp_names })
+\end{code}
-----
-sub :: ImplicitEnv -> ([(RdrName,RnName)], [(RdrName,RnName)]) -> ImplicitEnv
-sub (val_ment, tc_ment) (val_defds, tc_defds)
- = (delListFromFM val_ment (map fst val_defds),
- delListFromFM tc_ment (map fst tc_defds))
-\end{code}
+%*********************************************************
+%* *
+\subsection{Getting binders out of a declaration}
+%* *
+%*********************************************************
-% ------------------------------
+@getDeclBinders@ returns the names for a @RdrNameHsDecl@.
+It's used for both source code (from @availsFromDecl@) and interface files
+(from @loadDecl@).
-@cacheInstModules@: cache instance modules specified in imports
+It doesn't deal with source-code specific things: @ValD@, @DefD@. They
+are handled by the sourc-code specific stuff in @RnNames@.
\begin{code}
-cacheInstModules :: IfaceCache -> [Module] -> IO (Bag Error)
-cacheInstModules iface_cache imp_mods
- = readVar iface_cache `thenPrimIO` \ (iface_fm, _) ->
- let
- imp_ifaces = [ iface | Just iface <- map (lookupFM iface_fm) imp_mods ]
- (imp_imods, _) = removeDups cmpPString (bagToList (unionManyBags (map get_ims imp_ifaces)))
- get_ims (ParsedIface _ _ _ _ _ ims _ _ _ _ _) = ims
- in
- accumulate (map (cachedIface iface_cache) imp_imods) >>= \ err_or_ifaces ->
+getDeclBinders :: (RdrName -> SrcLoc -> RnM d Name) -- New-name function
+ -> RdrNameHsDecl
+ -> RnM d (Maybe AvailInfo)
- -- Sanity Check:
- -- Assert that instance modules given by direct imports contains
- -- instance modules extracted from all visited modules
+getDeclBinders new_name (TyClD (TyData _ _ tycon _ condecls _ _ src_loc))
+ = new_name tycon src_loc `thenRn` \ tycon_name ->
+ getConFieldNames new_name condecls `thenRn` \ sub_names ->
+ returnRn (Just (AvailTC tycon_name (tycon_name : nub sub_names)))
+ -- The "nub" is because getConFieldNames can legitimately return duplicates,
+ -- when a record declaration has the same field in multiple constructors
- readVar iface_cache `thenPrimIO` \ (all_iface_fm, _) ->
+getDeclBinders new_name (TyClD (TySynonym tycon _ _ src_loc))
+ = new_name tycon src_loc `thenRn` \ tycon_name ->
+ returnRn (Just (AvailTC tycon_name [tycon_name]))
+
+getDeclBinders new_name (TyClD (ClassDecl _ cname _ _ sigs _ _ _ _ _ _ src_loc))
+ = new_name cname src_loc `thenRn` \ class_name ->
+
+ -- Record the names for the class ops
let
- all_ifaces = eltsFM all_iface_fm
- (all_imods, _) = removeDups cmpPString (bagToList (unionManyBags (map get_ims (all_ifaces))))
+ -- just want class-op sigs
+ op_sigs = filter isClassOpSig sigs
in
- ASSERT(sortLt (<) imp_imods == sortLt (<) all_imods)
+ mapRn (getClassOpNames new_name) op_sigs `thenRn` \ sub_names ->
- return (bag_errs err_or_ifaces)
- where
- bag_errs [] = emptyBag
- bag_errs (Failed err :rest) = err `consBag` bag_errs rest
- bag_errs (Succeeded _:rest) = bag_errs rest
-\end{code}
+ returnRn (Just (AvailTC class_name (class_name : sub_names)))
+getDeclBinders new_name (SigD (IfaceSig var ty prags src_loc))
+ = new_name var src_loc `thenRn` \ var_name ->
+ returnRn (Just (Avail var_name))
-@rnIfaceInstStuff@: Deal with instance declarations from interface files.
+getDeclBinders new_name (FixD _) = returnRn Nothing
-\begin{code}
-type InstanceEnv = FiniteMap (RdrName, RdrName) Int
-
-rnIfaceInstStuff
- :: IfaceCache -- all about ifaces we've read
- -> Module
- -> UniqSupply
- -> RnEnv -- current occ env
- -> InstanceEnv -- instances for these tycon/class pairs done
- -> To_Return
- -> IO (To_Return,
- InstanceEnv, -- extended instance env
- RnEnv, -- final occ env
- [RnName]) -- new unknown names
-
-rnIfaceInstStuff iface_cache modname us occ_env done_inst_env to_return
- = -- all the instance decls we might even want to consider
- -- are in the ParsedIfaces that are in our cache
-
- readVar iface_cache `thenPrimIO` \ (iface_fm, _) ->
- let
- all_ifaces = eltsFM iface_fm
- all_insts = unionManyBags (map get_insts all_ifaces)
- interesting_insts = filter want_inst (bagToList all_insts)
+ -- foreign declarations
+getDeclBinders new_name (ForD (ForeignDecl nm kind _ dyn _ loc))
+ | binds_haskell_name kind dyn
+ = new_name nm loc `thenRn` \ name ->
+ returnRn (Just (Avail name))
- -- Sanity Check:
- -- Assert that there are no more instances for the done instances
+ | otherwise -- a foreign export
+ = lookupImplicitOccRn nm `thenRn_`
+ returnRn Nothing
- claim_done = filter is_done_inst (bagToList all_insts)
- claim_done_env = foldr add_done_inst emptyFM claim_done
- has_val fm (k,i) = case lookupFM fm k of { Nothing -> False; Just v -> i == v }
- in
- {-
- pprTrace "all_insts:\n" (ppr_insts (bagToList all_insts)) $
- pprTrace "interesting_insts:\n" (ppr_insts interesting_insts) $
- -}
- ASSERT(sizeFM done_inst_env == sizeFM claim_done_env)
- ASSERT(all (has_val claim_done_env) (fmToList done_inst_env))
-
- case (initRn False{-iface-} modname occ_env us (
- setExtraRn emptyUFM{-no fixities-} $
- mapRn rnIfaceInst interesting_insts `thenRn` \ insts ->
- getImplicitUpRn `thenRn` \ implicits ->
- returnRn (insts, implicits))) of {
- ((if_insts, if_implicits), if_errs, if_warns) ->
-
- return (add_insts if_insts $
- add_implicits if_implicits $
- add_errs if_errs $
- add_warns if_warns to_return,
- foldr add_done_inst done_inst_env interesting_insts,
- add_imp_occs if_implicits occ_env,
- eltsFM (fst if_implicits) ++ eltsFM (snd if_implicits))
- }
- where
- get_insts (ParsedIface _ _ _ _ _ _ _ _ _ insts _) = insts
+getDeclBinders new_name (DefD _) = returnRn Nothing
+getDeclBinders new_name (InstD _) = returnRn Nothing
+getDeclBinders new_name (RuleD _) = returnRn Nothing
- add_done_inst (InstSig clas tycon _ _) inst_env
- = addToFM_C (+) inst_env (tycon,clas) 1
+binds_haskell_name (FoImport _) _ = True
+binds_haskell_name FoLabel _ = True
+binds_haskell_name FoExport ext_nm = isDynamicExtName ext_nm
- is_done_inst (InstSig clas tycon _ _)
- = maybeToBool (lookupFM done_inst_env (tycon,clas))
+----------------
+getConFieldNames new_name (ConDecl con _ _ _ (RecCon fielddecls) src_loc : rest)
+ = mapRn (\n -> new_name n src_loc) (con:fields) `thenRn` \ cfs ->
+ getConFieldNames new_name rest `thenRn` \ ns ->
+ returnRn (cfs ++ ns)
+ where
+ fields = concat (map fst fielddecls)
- add_imp_occs (val_imps, tc_imps) occ_env
- = case extendGlobalRnEnv occ_env (fmToList val_imps) (fmToList tc_imps) of
- (ext_occ_env, occ_dups) -> ASSERT(isEmptyBag occ_dups)
- ext_occ_env
+getConFieldNames new_name (ConDecl con _ _ _ condecl src_loc : rest)
+ = new_name con src_loc `thenRn` \ n ->
+ (case condecl of
+ NewCon _ (Just f) ->
+ new_name f src_loc `thenRn` \ new_f ->
+ returnRn [n,new_f]
+ _ -> returnRn [n]) `thenRn` \ nn ->
+ getConFieldNames new_name rest `thenRn` \ ns ->
+ returnRn (nn ++ ns)
- want_inst i@(InstSig clas tycon _ _)
- = -- it's a "good instance" (one to hang onto) if we have a
- -- chance of referring to *both* the class and tycon later on ...
+getConFieldNames new_name [] = returnRn []
- mentionable tycon && mentionable clas && not (is_done_inst i)
- where
- mentionable nm
- = case lookupTcRnEnv occ_env nm of
- Just _ -> True
- Nothing -> -- maybe it's builtin
- case nm of
- Qual _ _ -> False
- Unqual n ->
- case (lookupFM b_tc_names n) of
- Just _ -> True
- Nothing -> maybeToBool (lookupFM b_keys n)
-
- (b_tc_names, b_keys) -- pretty UGLY ...
- = case builtinNameInfo of ((_,builtin_tcs),b_keys,_) -> (builtin_tcs,b_keys)
-
- ppr_insts insts
- = ppAboves (map ppr_inst insts)
- where
- ppr_inst (InstSig c t _ inst_decl)
- = ppCat [ppr PprDebug c, ppr PprDebug t, ppr PprDebug inst_decl]
+getClassOpNames new_name (ClassOpSig op _ _ _ src_loc) = new_name op src_loc
\end{code}
-\begin{code}
-rnIfaceInst :: RdrIfaceInst -> RnM_Fixes _RealWorld RenamedInstDecl
+@getDeclSysBinders@ gets the implicit binders introduced by a decl.
+A the moment that's just the tycon and datacon that come with a class decl.
+They aren't returned by @getDeclBinders@ because they aren't in scope;
+but they {\em should} be put into the @DeclsMap@ of this module.
-rnIfaceInst (InstSig _ _ _ inst_decl) = rnInstDecl inst_decl
-\end{code}
+Note that this excludes the default-method names of a class decl,
+and the dict fun of an instance decl, because both of these have
+bindings of their own elsewhere.
\begin{code}
-finalIfaceInfo ::
- IfaceCache -- iface cache
- -> [RnName] -- all imported names required
- -> [Module] -- directly imported modules
- -> IO (VersionInfo, -- info about version numbers
- [Module]) -- special instance modules
+getDeclSysBinders new_name (TyClD (ClassDecl _ cname _ _ sigs _ _ tname dname dwname snames src_loc))
+ = sequenceRn [new_name n src_loc | n <- (tname : dname : dwname : snames)]
-type VersionInfo = [(Module, Version, [(FAST_STRING, Version)])]
+getDeclSysBinders new_name (TyClD (TyData _ _ _ _ cons _ _ _))
+ = sequenceRn [new_name wkr_name src_loc | ConDecl _ wkr_name _ _ _ src_loc <- cons]
-finalIfaceInfo iface_cache imps_reqd imp_mods
- = return ([], [])
+getDeclSysBinders new_name other_decl
+ = returnRn []
\end{code}
+%*********************************************************
+%* *
+\subsection{Reading an interface file}
+%* *
+%*********************************************************
\begin{code}
-noIfaceErr mod sty
- = ppCat [ppPStr SLIT("Could not find interface for:"), ppPStr mod]
+findAndReadIface :: SDoc -> ModuleName
+ -> IsBootInterface -- True <=> Look for a .hi-boot file
+ -- False <=> Look for .hi file
+ -> RnM d (Either Message ParsedIface)
+ -- Nothing <=> file not found, or unreadable, or illegible
+ -- Just x <=> successfully found and parsed
+
+findAndReadIface doc_str mod_name hi_boot_file
+ = traceRn trace_msg `thenRn_`
+ -- we keep two maps for interface files,
+ -- one for 'normal' ones, the other for .hi-boot files,
+ -- hence the need to signal which kind we're interested.
+
+ getHiMaps `thenRn` \ (search_path, hi_map, hiboot_map) ->
+ let
+ relevant_map | hi_boot_file = hiboot_map
+ | otherwise = hi_map
+ in
+ case lookupFM relevant_map mod_name of
+ -- Found the file
+ Just fpath -> traceRn (ptext SLIT("...reading from") <+> text fpath) `thenRn_`
+ readIface mod_name fpath
+
+ -- Can't find it
+ Nothing -> traceRn (ptext SLIT("...not found")) `thenRn_`
+ returnRn (Left (noIfaceErr mod_name hi_boot_file search_path))
+
+ where
+ trace_msg = sep [hsep [ptext SLIT("Reading"),
+ if hi_boot_file then ptext SLIT("[boot]") else empty,
+ ptext SLIT("interface for"),
+ pprModuleName mod_name <> semi],
+ nest 4 (ptext SLIT("reason:") <+> doc_str)]
+\end{code}
+
+@readIface@ tries just the one file.
-noDeclInIfaceErr mod str sty
- = ppBesides [ppPStr SLIT("Could not find interface declaration of: "),
- ppPStr mod, ppStr ".", ppPStr str]
+\begin{code}
+readIface :: ModuleName -> String -> RnM d (Either Message ParsedIface)
+ -- Nothing <=> file not found, or unreadable, or illegible
+ -- Just x <=> successfully found and parsed
+readIface wanted_mod file_path
+ = ioToRnM (hGetStringBuffer False file_path) `thenRn` \ read_result ->
+ case read_result of
+ Right contents ->
+ case parseIface contents
+ PState{ bol = 0#, atbol = 1#,
+ context = [],
+ glasgow_exts = 1#,
+ loc = mkSrcLoc (mkFastString file_path) 1 } of
+ POk _ (PIface iface) ->
+ warnCheckRn (read_mod == wanted_mod)
+ (hiModuleNameMismatchWarn wanted_mod read_mod) `thenRn_`
+ returnRn (Right iface)
+ where
+ read_mod = moduleName (pi_mod iface)
+
+ PFailed err -> bale_out err
+ parse_result -> bale_out empty
+ -- This last case can happen if the interface file is (say) empty
+ -- in which case the parser thinks it looks like an IdInfo or
+ -- something like that. Just an artefact of the fact that the
+ -- parser is used for several purposes at once.
+
+ Left io_err -> bale_out (text (show io_err))
+ where
+ bale_out err = returnRn (Left (badIfaceFile file_path err))
+\end{code}
-cannaeReadErr file err sty
- = ppBesides [ppPStr SLIT("Failed in reading file: "), ppStr file, ppStr "; error=", ppStr (show err)]
+%*********************************************************
+%* *
+\subsection{Errors}
+%* *
+%*********************************************************
-ifaceLookupWiredErr msg n sty
- = ppBesides [ppPStr SLIT("Why am I looking up a wired-in "), ppStr msg, ppChar ':', ppr sty n]
+\begin{code}
+noIfaceErr mod_name boot_file search_path
+ = vcat [ptext SLIT("Could not find interface file for") <+> quotes (pprModuleName mod_name),
+ ptext SLIT("in the directories") <+>
+ -- \& to avoid cpp interpreting this string as a
+ -- comment starter with a pre-4.06 mkdependHS --SDM
+ vcat [ text dir <> text "/\&*" <> pp_suffix suffix
+ | (dir,suffix) <- search_path]
+ ]
+ where
+ pp_suffix suffix | boot_file = ptext SLIT(".hi-boot")
+ | otherwise = text suffix
+
+badIfaceFile file err
+ = vcat [ptext SLIT("Bad interface file:") <+> text file,
+ nest 4 err]
+
+getDeclErr name
+ = vcat [ptext SLIT("Failed to find interface decl for") <+> quotes (ppr name),
+ ptext SLIT("from module") <+> quotes (ppr (nameModule name))
+ ]
+
+getDeclWarn name loc
+ = sep [ptext SLIT("Failed to find (optional) interface decl for") <+> quotes (ppr name),
+ ptext SLIT("desired at") <+> ppr loc]
+
+importDeclWarn name
+ = sep [ptext SLIT(
+ "Compiler tried to import decl from interface file with same name as module."),
+ ptext SLIT(
+ "(possible cause: module name clashes with interface file already in scope.)")
+ ] $$
+ hsep [ptext SLIT("name:"), quotes (ppr name)]
+
+warnRedundantSourceImport mod_name
+ = ptext SLIT("Unnecessary {- SOURCE -} in the import of module")
+ <+> quotes (pprModuleName mod_name)
+
+hiModuleNameMismatchWarn :: ModuleName -> ModuleName -> Message
+hiModuleNameMismatchWarn requested_mod read_mod =
+ hsep [ ptext SLIT("Something is amiss; requested module name")
+ , pprModuleName requested_mod
+ , ptext SLIT("differs from name found in the interface file")
+ , pprModuleName read_mod
+ ]
-badIfaceLookupErr msg name decl sty
- = ppBesides [ppPStr SLIT("Expected a "), ppStr msg, ppPStr SLIT(" declaration, but got this: ???")]
\end{code}