%
-% (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,
- cacheInterface,
- readInterface,
- rnInterfaces,
- finalIfaceInfo,
- IfaceCache(..),
- VersionInfo(..),
- ParsedIface(..)
- ) where
+ getInterfaceExports,
+ getImportedInstDecls, getImportedRules,
+ lookupFixity, loadHomeInterface,
+ importDecl, recordSlurp,
+ getImportVersions, getSlurped,
-import PreludeGlaST ( returnPrimIO, thenPrimIO,
- readVar, writeVar, MutableVar(..) )
+ checkUpToDate,
-import Ubiq
+ getDeclBinders, getDeclSysBinders,
+ removeContext -- removeContext probably belongs somewhere else
+ ) where
-import HsSyn
-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 RnUtils ( RnEnv(..) )
+import RnHsSyn ( RenamedHsDecl, RenamedDeprecation )
+import ParseIface ( parseIface, IfaceStuff(..) )
-import Bag ( emptyBag )
-import ErrUtils ( Error(..), Warning(..) )
-import FiniteMap ( emptyFM, lookupFM, addToFM )
-import Pretty
-import Maybes ( MaybeErr(..) )
-import Util ( panic )
+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, isPrelModule,
+ ModuleName, WhereFrom(..),
+ )
+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 IfaceCache = MutableVar _RealWorld (FiniteMap Module ParsedIface,
- FiniteMap Module String)
+loadHomeInterface :: SDoc -> Name -> RnM d Ifaces
+loadHomeInterface doc_str name
+ = loadInterface doc_str (moduleName (nameModule name)) ImportBySystem `thenRn` \ (_, ifaces) ->
+ returnRn ifaces
+
+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 (pprModuleName mod <+> ptext SLIT("is a orphan-instance module")) mod ImportBySystem
+
+loadInterface :: SDoc -> ModuleName -> WhereFrom -> RnM d (Module, Ifaces)
+loadInterface doc_str mod_name from
+ = getIfacesRn `thenRn` \ ifaces ->
+ let
+ mod_map = iImpModInfo ifaces
+ mod_info = lookupFM mod_map mod_name
+ below_me = case mod_info of
+ Nothing -> False
+ Just (_, _, is_boot, _) -> not is_boot
+ in
+
+ -- Issue a warning for a redundant {- SOURCE -} import
+ -- It's redundant if the moduld is in the iImpModInfo at all,
+ -- because we arrange to read all the ordinary imports before
+ -- any of the {- SOURCE -} imports
+ warnCheckRn (not (below_me && case from of {ImportByUserSource -> True; other -> False}))
+ (warnRedundantSourceImport mod_name) `thenRn_`
+
+ -- CHECK WHETHER WE HAVE IT ALREADY
+ case mod_info of {
+ Just (_, _, _, Just (load_mod, _))
+ -> -- We're read it already so don't re-read it
+ returnRn (load_mod, ifaces) ;
+
+ mod_map_result ->
+
+ -- READ THE MODULE IN
+ findAndReadIface doc_str mod_name from below_me `thenRn` \ (hi_boot_read, read_result) ->
+ case read_result of {
+ Nothing -> -- 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, []))
+ new_ifaces = ifaces { iImpModInfo = new_mod_map }
+ in
+ setIfacesRn new_ifaces `thenRn_`
+ failWithRn (mod, new_ifaces) (noIfaceErr mod hi_boot_read) ;
+
+ -- Found and parsed!
+ Just (mod, 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
+ in
+ 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 mod_map (pi_usages iface)
+ other -> mod_map
+
+ -- Now add info about this module
+ mod_map2 = addToFM mod_map1 mod_name mod_details
+ mod_details = (pi_mod iface, pi_orphan iface, hi_boot_read, Just (mod, concat avails_s))
+
+ 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 (mod, new_ifaces)
+ }}
+
+addModDeps :: Module -> ImportedModuleInfo
+ -> [ImportVersion a] -> ImportedModuleInfo
+addModDeps mod mod_deps new_deps
+ = foldr add mod_deps new_deps
+ where
+ is_lib = isPrelModule mod -- Don't record dependencies when importing a prelude module
+ add (imp_mod, version, has_orphans, is_boot, _) deps
+ | is_lib && not has_orphans = deps
+ | otherwise = addToFM_C combine deps imp_mod (version, has_orphans, is_boot, Nothing)
+ -- Record dependencies for modules that are
+ -- either are dependent via a non-library module
+ -- or contain orphan rules or instance decls
+
+ 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
+
+ -- Ignore the other sorts of decl
+loadFixDecl mod_name fixity_env other_decl = returnRn fixity_env
+
+loadDecl :: Module
+ -> DeclsMap
+ -> (Version, RdrNameHsDecl)
+ -> RnM d DeclsMap
+
+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 ->
+
+ 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
+ -- 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)
-data ParsedIface = ParsedIface
+-- 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{Looking for interface files}
-* *
-*********************************************************
+
+%********************************************************
+%* *
+\subsection{Loading usage information}
+%* *
+%********************************************************
\begin{code}
-findHiFiles :: [String] -> PrimIO (FiniteMap Module String)
-findHiFiles dirs = returnPrimIO emptyFM
+checkUpToDate :: ModuleName -> RnMG Bool -- True <=> no need to recompile
+checkUpToDate mod_name
+ = getIfacesRn `thenRn` \ ifaces ->
+ findAndReadIface doc_str mod_name
+ ImportByUser
+ (error "checkUpToDate") `thenRn` \ (_, read_result) ->
+
+ -- CHECK WHETHER WE HAVE IT ALREADY
+ case read_result of
+ Nothing -> -- Old interface file not found, so we'd better bail out
+ traceRn (sep [ptext SLIT("Didnt find old iface"),
+ pprModuleName mod_name]) `thenRn_`
+ returnRn False
+
+ Just (_, iface)
+ -> -- Found it, so now check it
+ checkModUsage (pi_usages iface)
+ where
+ -- Only look in current directory, with suffix .hi
+ doc_str = sep [ptext SLIT("need usage info from"), pprModuleName mod_name]
+
+checkModUsage [] = returnRn True -- 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)
+ = loadInterface doc_str mod_name ImportBySystem `thenRn` \ (mod, ifaces) ->
+ let
+ maybe_mod_vers = case lookupFM (iImpModInfo ifaces) mod_name of
+ Just (version, _, _, Just (_, _)) -> Just version
+ other -> Nothing
+ in
+ case maybe_mod_vers of {
+ Nothing -> -- If we can't find a version number for the old module then
+ -- bail out saying things aren't up to date
+ traceRn (sep [ptext SLIT("Can't find version number for module"),
+ pprModuleName mod_name])
+ `thenRn_` returnRn False ;
+
+ Just new_mod_vers ->
+
+ -- 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 False; -- 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 False -- This one failed, so just bail out now
+ }}
+ where
+ doc_str = sep [ptext SLIT("need version info for"), pprModuleName mod_name]
+
+
+checkEntityUsage mod decls []
+ = returnRn True -- 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 False
+
+ 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 False
\end{code}
-*********************************************************
-* *
-\subsection{Reading interface files}
-* *
-*********************************************************
+
+%*********************************************************
+%* *
+\subsection{Getting in a declaration}
+%* *
+%*********************************************************
\begin{code}
-cacheInterface :: IfaceCache -> Module
- -> PrimIO (MaybeErr ParsedIface Error)
-
-cacheInterface iface_var mod
- = readVar iface_var `thenPrimIO` \ (iface_fm, file_fm) ->
- case lookupFM iface_fm mod of
- Just iface -> returnPrimIO (Succeeded iface)
- Nothing ->
- case lookupFM file_fm mod of
- Nothing -> returnPrimIO (Failed (noIfaceErr mod))
- Just file ->
- readInterface file mod `thenPrimIO` \ read_iface ->
- case read_iface of
- Failed err -> returnPrimIO (Failed err)
- Succeeded iface ->
- let
- iface_fm' = addToFM iface_fm mod iface
- in
- writeVar iface_var (iface_fm', file_fm) `thenPrimIO` \ _ ->
- returnPrimIO (Succeeded iface)
-
-
-readInterface :: String -> Module
- -> PrimIO (MaybeErr ParsedIface Error)
-
-readInterface file mod = panic "readInterface"
+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}
+\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
+ doc_str = ptext SLIT("need decl for") <+> ppr needed_name
+\end{code}
+
+@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.
+
+\item similarly for synonum type constructor
+
+\item if the wired-in name is another wired-in Id, it marks as ``occurrences''
+ the free vars of the Id's type.
+
+\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.
+
+
+
+
+%*********************************************************
+%* *
+\subsection{Getting what a module exports}
+%* *
+%*********************************************************
+
+@getInterfaceExports@ is called only for directly-imported modules.
\begin{code}
-rnInterfaces ::
- IfaceCache -- iface cache
- -> RnEnv -- original name env
- -> UniqSupply
- -> RenamedHsModule -- module to extend with iface decls
- -> [RnName] -- imported names required
- -> PrimIO (RenamedHsModule, -- extended module
- ImplicitEnv, -- implicit names required
- Bag Error,
- Bag Warning)
-
-rnInterfaces iface_var occ_env us rn_module todo
- = returnPrimIO (rn_module, (emptyFM, emptyFM), emptyBag, emptyBag)
+getInterfaceExports :: ModuleName -> WhereFrom -> RnMG (Module, Avails)
+getInterfaceExports mod_name from
+ = loadInterface doc_str mod_name from `thenRn` \ (mod, ifaces) ->
+ case lookupFM (iImpModInfo ifaces) mod_name of
+ Nothing -> -- Not there; it must be that the interface file wasn't found;
+ -- the error will have been reported already.
+ -- (Actually loadInterface should put the empty export env in there
+ -- anyway, but this does no harm.)
+ returnRn (mod, [])
+
+ Just (_, _, _, Just (mod, avails)) -> returnRn (mod, avails)
+ where
+ doc_str = sep [pprModuleName mod_name, ptext SLIT("is directly imported")]
\end{code}
+%*********************************************************
+%* *
+\subsection{Instance declarations are handled specially}
+%* *
+%*********************************************************
+
\begin{code}
-finalIfaceInfo ::
- IfaceCache -- iface cache
- -> [RnName] -- all imported names required
- -> [Module] -- directly imported modules
- -> PrimIO (VersionInfo, -- info about version numbers
- [Module]) -- special instance modules
+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
+ orphan_mods =
+ [mod | (mod, (_, True, _, Nothing)) <- fmToList (iImpModInfo ifaces)]
+ in
+ loadOrphanModules orphan_mods `thenRn_`
+
+ -- 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
+ (decls, new_insts) = selectGated gates (iInsts ifaces)
+ in
+ 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
+
+ load_home gate | isLocallyDefined gate
+ = returnRn ()
+ | otherwise
+ = loadHomeInterface (ppr gate <+> text "is an instance gate") gate `thenRn_`
+ returnRn ()
+
+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
+ gates = iSlurp ifaces -- Anything at all that's been slurped
+ (decls, new_rules) = selectGated gates (iRules ifaces)
+ in
+ 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
-type VersionInfo = [(Module, Version, [(FAST_STRING, Version)])]
+ | 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)
-finalIfaceInfo iface_var imps_reqd imp_mods
- = returnPrimIO ([], [])
+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.
+
+\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
+ 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.
+ go_for_it (Specifically [])
+
+ Just (mod, _) -- We did open the interface
+ | 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 = isPrelModule mod
+
+ in
+
+ 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}
-noIfaceErr mod sty
- = ppCat [ppStr "Could not find interface for", ppPStr mod]
+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
+ 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
+ setIfacesRn (ifaces { iSlurp = new_slurped_names,
+ iVSlurp = new_imp_names })
+\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@).
+
+It doesn't deal with source-code specific things: @ValD@, @DefD@. They
+are handled by the sourc-code specific stuff in @RnNames@.
+
+\begin{code}
+getDeclBinders :: (RdrName -> SrcLoc -> RnM d Name) -- New-name function
+ -> RdrNameHsDecl
+ -> RnM d (Maybe AvailInfo)
+
+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
+
+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
+ -- just want class-op sigs
+ op_sigs = filter isClassOpSig sigs
+ in
+ mapRn (getClassOpNames new_name) op_sigs `thenRn` \ sub_names ->
+
+ 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))
+
+getDeclBinders new_name (FixD _) = returnRn Nothing
+
+ -- 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))
+
+ | otherwise -- a foreign export
+ = lookupImplicitOccRn nm `thenRn_`
+ returnRn Nothing
+
+getDeclBinders new_name (DefD _) = returnRn Nothing
+getDeclBinders new_name (InstD _) = returnRn Nothing
+getDeclBinders new_name (RuleD _) = returnRn Nothing
+
+binds_haskell_name (FoImport _) _ = True
+binds_haskell_name FoLabel _ = True
+binds_haskell_name FoExport ext_nm = isDynamicExtName ext_nm
+
+----------------
+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)
+
+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)
+
+getConFieldNames new_name [] = returnRn []
+
+getClassOpNames new_name (ClassOpSig op _ _ _ src_loc) = new_name op src_loc
+\end{code}
+
+@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.
+
+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}
+getDeclSysBinders new_name (TyClD (ClassDecl _ cname _ _ sigs _ _ tname dname dwname snames src_loc))
+ = sequenceRn [new_name n src_loc | n <- (tname : dname : dwname : snames)]
+
+getDeclSysBinders new_name (TyClD (TyData _ _ _ _ cons _ _ _))
+ = sequenceRn [new_name wkr_name src_loc | ConDecl _ wkr_name _ _ _ src_loc <- cons]
+
+getDeclSysBinders new_name other_decl
+ = returnRn []
+\end{code}
+
+%*********************************************************
+%* *
+\subsection{Reading an interface file}
+%* *
+%*********************************************************
+
+\begin{code}
+findAndReadIface :: SDoc -> ModuleName -> WhereFrom
+ -> Bool -- Only relevant for SystemImport
+ -- True <=> Look for a .hi file
+ -- False <=> Look for .hi-boot file unless there's
+ -- a library .hi file
+ -> RnM d (Bool, Maybe (Module, ParsedIface))
+ -- Bool is True if the interface actually read was a .hi-boot one
+ -- Nothing <=> file not found, or unreadable, or illegible
+ -- Just x <=> successfully found and parsed
+
+findAndReadIface doc_str mod_name from hi_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` \ hi_maps ->
+
+ case find_path from hi_maps of
+ -- Found the file
+ (hi_boot, Just (fpath, mod)) -> traceRn (ptext SLIT("...reading from") <+> text fpath)
+ `thenRn_`
+ readIface mod fpath `thenRn` \ result ->
+ returnRn (hi_boot, result)
+ (hi_boot, Nothing) -> traceRn (ptext SLIT("...not found")) `thenRn_`
+ returnRn (hi_boot, Nothing)
+ where
+ find_path ImportByUser (hi_map, _) = (False, lookupFM hi_map mod_name)
+ find_path ImportByUserSource (_, hiboot_map) = (True, lookupFM hiboot_map mod_name)
+
+ find_path ImportBySystem (hi_map, hiboot_map)
+ | hi_file
+ = -- If the module we seek is in our dependent set,
+ -- Look for a .hi file
+ (False, lookupFM hi_map mod_name)
+
+ | otherwise
+ -- Check if there's a prelude module of that name
+ -- If not, look for an hi-boot file
+ = case lookupFM hi_map mod_name of
+ stuff@(Just (_, mod)) | isPrelModule mod -> (False, stuff)
+ other -> (True, lookupFM hiboot_map mod_name)
+
+ trace_msg = sep [hsep [ptext SLIT("Reading"),
+ ppr from,
+ ptext SLIT("interface for"),
+ pprModuleName mod_name <> semi],
+ nest 4 (ptext SLIT("reason:") <+> doc_str)]
+\end{code}
+
+@readIface@ tries just the one file.
+
+\begin{code}
+readIface :: Module -> String -> RnM d (Maybe (Module, ParsedIface))
+ -- Nothing <=> file not found, or unreadable, or illegible
+ -- Just x <=> successfully found and parsed
+readIface the_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 mod_nm iface) ->
+ warnCheckRn (mod_nm == moduleName the_mod)
+ (hiModuleNameMismatchWarn the_mod mod_nm) `thenRn_`
+ returnRn (Just (the_mod, iface))
+
+ PFailed err -> failWithRn Nothing err
+ other -> failWithRn Nothing (ptext SLIT("Unrecognisable interface file"))
+ -- 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 err
+ | isDoesNotExistError err -> returnRn Nothing
+ | otherwise -> failWithRn Nothing (cannaeReadFile file_path err)
+\end{code}
+
+%*********************************************************
+%* *
+\subsection{Errors}
+%* *
+%*********************************************************
+
+\begin{code}
+noIfaceErr filename boot_file
+ = hsep [ptext SLIT("Could not find valid"), boot,
+ ptext SLIT("interface file"), quotes (pprModule filename)]
+ where
+ boot | boot_file = ptext SLIT("[boot]")
+ | otherwise = empty
+
+cannaeReadFile file err
+ = hcat [ptext SLIT("Failed in reading file: "),
+ text file,
+ ptext SLIT("; error="),
+ text (show 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 :: Module -> ModuleName -> Message
+hiModuleNameMismatchWarn requested_mod mod_nm =
+ hsep [ ptext SLIT("Something is amiss; requested module name")
+ , pprModule requested_mod
+ , ptext SLIT("differs from name found in the interface file ")
+ , pprModuleName mod_nm
+ ]
+
\end{code}