%
-% (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 (
+module RnIfaces
+ (
getInterfaceExports,
- getImportedInstDecls,
- getSpecialInstModules,
- getDecl, getWiredInDecl,
- getImportVersions,
-
- checkUpToDate,
+ recordLocalSlurps,
+ mkImportInfo,
- getDeclBinders,
- mkSearchPath
- ) where
+ slurpImpDecls, closeDecls,
-IMP_Ubiq()
+ RecompileRequired, outOfDate, upToDate, recompileRequired
+ )
+where
+#include "HsVersions.h"
-import HsSyn ( HsDecl(..), TyDecl(..), ClassDecl(..), HsTyVar, Bind, HsExpr, Sig(..),
- HsBinds(..), MonoBinds, DefaultDecl, ConDecl(..), HsType, BangType, IfaceSig(..),
- FixityDecl(..), Fixity, Fake, InPat, InstDecl(..), SYN_IE(Version), HsIdInfo
+import CmdLineOpts ( opt_IgnoreIfacePragmas, opt_NoPruneDecls )
+import HscTypes
+import HsSyn ( HsDecl(..), Sig(..), TyClDecl(..), ConDecl(..), ConDetails(..),
+ InstDecl(..), HsType(..), hsTyVarNames, getBangType
+ )
+import HsImpExp ( ImportDecl(..) )
+import RdrHsSyn ( RdrNameTyClDecl, RdrNameInstDecl, RdrNameRuleDecl )
+import RnHsSyn ( RenamedHsDecl, RenamedTyClDecl,
+ extractHsTyNames, extractHsCtxtTyNames,
+ tyClDeclFVs, ruleDeclFVs, instDeclFVs
)
-import HsPragmas ( noGenPragmas )
-import RdrHsSyn ( SYN_IE(RdrNameHsDecl), SYN_IE(RdrNameInstDecl),
- RdrName, rdrNameOcc
+import RnHiFiles ( tryLoadInterface, loadHomeInterface, loadInterface,
+ loadOrphanModules
)
-import RnEnv ( newGlobalName, lookupRn, addImplicitOccsRn, availNames )
-import RnSource ( rnHsType )
+import RnSource ( rnTyClDecl, rnInstDecl, rnIfaceRuleDecl )
+import RnEnv
import RnMonad
-import ParseIface ( parseIface )
-
-import ErrUtils ( SYN_IE(Error), SYN_IE(Warning) )
-import FiniteMap ( FiniteMap, emptyFM, unitFM, lookupFM, addToFM, addListToFM, fmToList )
-import Name ( Name {-instance NamedThing-}, Provenance, OccName(..),
- modAndOcc, occNameString, moduleString, pprModule,
- NameSet(..), emptyNameSet, unionNameSets, nameSetToList,
- minusNameSet, mkNameSet,
- isWiredInName, maybeWiredInTyConName, maybeWiredInIdName
- )
-import Id ( GenId, Id(..), idType, dataConTyCon, isDataCon )
-import TyCon ( TyCon, tyConDataCons, isSynTyCon, getSynTyConDefn )
+import Id ( idType )
import Type ( namesOfType )
-import TyVar ( GenTyVar )
-import SrcLoc ( mkIfaceSrcLoc )
-import PrelMods ( gHC__ )
+import TyCon ( isSynTyCon, getSynTyConDefn )
+import Name ( Name {-instance NamedThing-}, nameOccName,
+ nameModule, isLocalName, nameUnique,
+ NamedThing(..)
+ )
+import Name ( elemNameEnv, delFromNameEnv )
+import Module ( Module, ModuleEnv,
+ moduleName, isHomeModule,
+ ModuleName, WhereFrom(..),
+ emptyModuleEnv,
+ extendModuleEnv_C, foldModuleEnv, lookupModuleEnv,
+ elemModuleSet, extendModuleSet
+ )
+import NameSet
+import PrelInfo ( wiredInThingEnv, fractionalClassKeys )
+import TysWiredIn ( doubleTyCon )
+import Maybes ( orElse )
+import FiniteMap
+import Outputable
import Bag
-import Maybes ( MaybeErr(..), expectJust, maybeToBool )
-import ListSetOps ( unionLists )
-import Pretty
-import PprStyle ( PprStyle(..) )
-import Util ( pprPanic )
+import Util ( sortLt )
\end{code}
-
%*********************************************************
%* *
-\subsection{Loading a new interface file}
+\subsection{Getting what a module exports}
%* *
%*********************************************************
-\begin{code}
-loadInterface :: Pretty -> Module -> RnMG Ifaces
-loadInterface doc_str load_mod
- = getIfacesRn `thenRn` \ ifaces ->
- let
- Ifaces this_mod mod_vers_map export_env_map vers_map decls_map inst_map inst_mods = ifaces
- in
- -- CHECK WHETHER WE HAVE IT ALREADY
- if maybeToBool (lookupFM export_env_map load_mod)
- then
- returnRn ifaces -- Already in the cache; don't re-read it
- else
+@getInterfaceExports@ is called only for directly-imported modules.
- -- READ THE MODULE IN
- findAndReadIface doc_str load_mod `thenRn` \ read_result ->
- case read_result of {
- -- Check for not found
- Nothing -> -- Not found, so add an empty export env to the Ifaces map
- -- so that we don't look again
- let
- new_export_env_map = addToFM export_env_map load_mod ([],[])
- new_ifaces = Ifaces this_mod mod_vers_map
- new_export_env_map
- vers_map decls_map inst_map inst_mods
- in
- setIfacesRn new_ifaces `thenRn_`
- failWithRn new_ifaces (noIfaceErr load_mod) ;
-
- -- Found and parsed!
- Just (ParsedIface _ mod_vers usages exports rd_inst_mods fixs decls insts) ->
-
- -- LOAD IT INTO Ifaces
- mapRn loadExport exports `thenRn` \ avails_s ->
- foldlRn (loadDecl load_mod) (decls_map,vers_map) decls `thenRn` \ (new_decls_map, new_vers_map) ->
- foldlRn (loadInstDecl load_mod) inst_map insts `thenRn` \ new_insts_map ->
- let
- export_env = (concat avails_s, fixs)
-
- -- Exclude this module from the "special-inst" modules
- new_inst_mods = inst_mods `unionLists` (filter (/= this_mod) rd_inst_mods)
-
- new_ifaces = Ifaces this_mod
- (addToFM mod_vers_map load_mod mod_vers)
- (addToFM export_env_map load_mod export_env)
- new_vers_map
- new_decls_map
- new_insts_map
- new_inst_mods
- in
- setIfacesRn new_ifaces `thenRn_`
- returnRn new_ifaces
- }
-
-loadExport :: ExportItem -> RnMG [AvailInfo]
-loadExport (mod, entities)
- = mapRn load_entity entities
- where
- new_name occ = newGlobalName mod occ
-
- load_entity (occ, occs)
- = new_name occ `thenRn` \ name ->
- mapRn new_name occs `thenRn` \ names ->
- returnRn (Avail name names)
-
-loadVersion :: Module -> VersionMap -> (OccName,Version) -> RnMG VersionMap
-loadVersion mod vers_map (occ, version)
- = newGlobalName mod occ `thenRn` \ name ->
- returnRn (addToFM vers_map name version)
-
-
-loadDecl :: Module -> (DeclsMap, VersionMap)
- -> (Version, RdrNameHsDecl)
- -> RnMG (DeclsMap, VersionMap)
-loadDecl mod (decls_map, vers_map) (version, decl)
- = getDeclBinders new_implicit_name decl `thenRn` \ avail@(Avail name _) ->
- returnRn (addListToFM decls_map
- [(name,(avail,decl)) | name <- availNames avail],
- addToFM vers_map name version
- )
+\begin{code}
+getInterfaceExports :: ModuleName -> WhereFrom -> RnMG (Module, [(ModuleName,Avails)])
+getInterfaceExports mod_name from
+ = loadInterface doc_str mod_name from `thenRn` \ iface ->
+ returnRn (mi_module iface, mi_exports iface)
where
- new_implicit_name rdr_name loc = newGlobalName mod (rdrNameOcc rdr_name)
-
-loadInstDecl :: Module -> Bag IfaceInst -> RdrNameInstDecl -> RnMG (Bag IfaceInst)
-loadInstDecl mod_name insts decl@(InstDecl inst_ty binds uprags dfun_name src_loc)
- = initRnMS emptyRnEnv mod_name InterfaceMode $
-
- -- Find out what type constructors and classes are mentioned in the
- -- instance declaration. We have to be a bit clever.
- --
- -- We want to rename the type so that we can find what
- -- (free) type constructors are inside it. But we must *not* thereby
- -- put new occurrences into the global pool because otherwise we'll force
- -- them all to be loaded. We kill two birds with ones stone by renaming
- -- with a fresh occurrence pool.
- findOccurrencesRn (rnHsType inst_ty) `thenRn` \ ty_names ->
-
- returnRn ((ty_names, mod_name, decl) `consBag` insts)
+ doc_str = sep [ppr mod_name, ptext SLIT("is directly imported")]
\end{code}
-%********************************************************
+%*********************************************************
%* *
-\subsection{Loading usage information}
+\subsection{Keeping track of what we've slurped, and version numbers}
%* *
-%********************************************************
+%*********************************************************
-\begin{code}
-checkUpToDate :: Module -> RnMG Bool -- True <=> no need to recompile
-checkUpToDate mod_name
- = findAndReadIface doc_str mod_name `thenRn` \ read_result ->
- case read_result of
- Nothing -> -- Old interface file not found, so we'd better bale out
- traceRn (ppSep [ppStr "Didnt find old iface", pprModule PprDebug mod_name]) `thenRn_`
- returnRn False
-
- Just (ParsedIface _ _ usages _ _ _ _ _)
- -> -- Found it, so now check it
- checkModUsage usages
- where
- -- Only look in current directory, with suffix .hi
- doc_str = ppSep [ppStr "Need usage info from", pprModule PprDebug mod_name]
+mkImportInof 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.
+We produce a line for every module B below the module, A, currently being
+compiled:
+ import B <n> ;
+to record the fact that A does import B indireclty. 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.
-checkModUsage [] = returnRn True -- Yes! Everything is up to date!
+\begin{code}
+mkImportInfo :: ModuleName -- Name of this module
+ -> [ImportDecl n] -- The import decls
+ -> RnMG [ImportVersion Name]
-checkModUsage ((mod, old_mod_vers, old_local_vers) : rest)
- = loadInterface doc_str mod `thenRn` \ ifaces ->
+mkImportInfo this_mod imports
+ = getIfacesRn `thenRn` \ ifaces ->
+ getHomeIfaceTableRn `thenRn` \ hit ->
let
- Ifaces _ mod_vers_map _ new_vers_map _ _ _ = ifaces
- maybe_new_mod_vers = lookupFM mod_vers_map mod
- Just new_mod_vers = maybe_new_mod_vers
+ (imp_pkg_mods, imp_home_names) = iVSlurp ifaces
+ pit = iPIT ifaces
+
+ import_all_mods :: [ModuleName]
+ -- Modules where we imported all the names
+ -- (apart from hiding some, perhaps)
+ import_all_mods = [ m | ImportDecl m _ _ _ imp_list _ <- imports,
+ import_all imp_list ]
+ where
+ import_all (Just (False, _)) = False -- Imports are specified explicitly
+ import_all other = True -- Everything is imported
+
+ -- mv_map groups together all the things imported and used
+ -- from a particular module in this package
+ -- We use a finite map because we want the domain
+ mv_map :: ModuleEnv [Name]
+ mv_map = foldNameSet add_mv emptyModuleEnv imp_home_names
+ add_mv name mv_map = extendModuleEnv_C add_item mv_map mod [name]
+ where
+ mod = nameModule name
+ add_item names _ = name:names
+
+ -- In our usage list we record
+ -- a) Specifically: Detailed version info for imports from modules in this package
+ -- Gotten from iVSlurp plus import_all_mods
+ --
+ -- b) Everything: Just the module version for imports from modules in other packages
+ -- Gotten from iVSlurp plus import_all_mods
+ --
+ -- c) NothingAtAll: The name only of modules, Baz, in this package that are 'below' us,
+ -- but which we didn't need at all (this is needed only to decide whether
+ -- to open Baz.hi or Baz.hi-boot higher up the tree).
+ -- 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 info.
+ -- These modules are in a combination of HIT/PIT and iImpModInfo
+ --
+ -- d) NothingAtAll: The name only of all orphan modules we know of (this is needed
+ -- so that anyone who imports us can find the orphan modules)
+ -- These modules are in a combination of HIT/PIT and iImpModInfo
+
+ import_info0 = foldModuleEnv mk_imp_info [] pit
+ import_info1 = foldModuleEnv mk_imp_info import_info0 hit
+ import_info = [ (mod_name, orphans, is_boot, NothingAtAll)
+ | (mod_name, (orphans, is_boot)) <- fmToList (iImpModInfo ifaces) ] ++
+ import_info1
+
+ mk_imp_info :: ModIface -> [ImportVersion Name] -> [ImportVersion Name]
+ mk_imp_info iface so_far
+
+ | Just ns <- lookupModuleEnv mv_map mod -- Case (a)
+ = go_for_it (Specifically mod_vers maybe_export_vers
+ (mk_import_items ns) rules_vers)
+
+ | mod `elemModuleSet` imp_pkg_mods -- Case (b)
+ = go_for_it (Everything mod_vers)
+
+ | import_all_mod -- Case (a) and (b); the import-all part
+ = if is_home_pkg_mod then
+ go_for_it (Specifically mod_vers (Just export_vers) [] rules_vers)
+ else
+ go_for_it (Everything mod_vers)
+
+ | is_home_pkg_mod || has_orphans -- Case (c) or (d)
+ = go_for_it NothingAtAll
+
+ | otherwise = so_far
+ where
+ go_for_it exports = (mod_name, has_orphans, mi_boot iface, exports) : so_far
+
+ mod = mi_module iface
+ mod_name = moduleName mod
+ is_home_pkg_mod = isHomeModule mod
+ version_info = mi_version iface
+ version_env = vers_decls version_info
+ mod_vers = vers_module version_info
+ rules_vers = vers_rules version_info
+ export_vers = vers_exports version_info
+ import_all_mod = mod_name `elem` import_all_mods
+ has_orphans = mi_orphan iface
+
+ -- The sort is to put them into canonical order
+ mk_import_items ns = [(n,v) | n <- sortLt lt_occ ns,
+ let v = lookupNameEnv version_env n `orElse`
+ pprPanic "mk_whats_imported" (ppr n)
+ ]
+ where
+ lt_occ n1 n2 = nameOccName n1 < nameOccName n2
+
+ maybe_export_vers | import_all_mod = Just (vers_exports version_info)
+ | otherwise = Nothing
in
- -- If we can't find a version number for the old module then
- -- bale out saying things aren't up to date
- if not (maybeToBool maybe_new_mod_vers) then
- returnRn False
- else
+ returnRn import_info
+\end{code}
- -- If the module version hasn't changed, just move on
- if new_mod_vers == old_mod_vers then
- traceRn (ppSep [ppStr "Module version unchanged:", pprModule PprDebug mod]) `thenRn_`
- checkModUsage rest
- else
- traceRn (ppSep [ppStr "Module version has changed:", pprModule PprDebug mod]) `thenRn_`
+%*********************************************************
+%* *
+\subsection{Slurping declarations}
+%* *
+%*********************************************************
- -- New module version, so check entities inside
- checkEntityUsage mod new_vers_map old_local_vers `thenRn` \ up_to_date ->
- if up_to_date then
- traceRn (ppStr "...but the bits I use havn'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 = ppSep [ppStr "need version info for", pprModule PprDebug mod]
+\begin{code}
+-------------------------------------------------------
+slurpImpDecls source_fvs
+ = traceRn (text "slurpImp" <+> fsep (map ppr (nameSetToList source_fvs))) `thenRn_`
+ -- The current slurped-set records all local things
+ slurpSourceRefs source_fvs `thenRn` \ (decls, needed) ->
-checkEntityUsage mod new_vers_map []
- = returnRn True -- Yes! All up to date!
+ -- Then get everything else
+ closeDecls decls needed
-checkEntityUsage mod new_vers_map ((occ_name,old_vers) : rest)
- = newGlobalName mod occ_name `thenRn` \ name ->
- case lookupFM new_vers_map name of
- Nothing -> -- We used it before, but it ain't there now
- traceRn (ppSep [ppStr "...and this no longer exported:", ppr PprDebug name]) `thenRn_`
- returnRn False
-
- Just new_vers -> -- It's there, but is it up to date?
- if new_vers == old_vers then
- -- Up to date, so check the rest
- checkEntityUsage mod new_vers_map rest
- else
- traceRn (ppSep [ppStr "...and this is out of date:", ppr PprDebug name]) `thenRn_`
- returnRn False -- Out of date, so bale out
-\end{code}
+-------------------------------------------------------
+slurpSourceRefs :: FreeVars -- Variables referenced in source
+ -> RnMG ([RenamedHsDecl],
+ FreeVars) -- Un-satisfied needs
+-- The declaration (and hence home module) of each gate has
+-- already been loaded
+slurpSourceRefs source_fvs
+ = go_outer [] -- Accumulating decls
+ emptyFVs -- Unsatisfied needs
+ emptyFVs -- Accumulating gates
+ (nameSetToList source_fvs) -- Things whose defn hasn't been loaded yet
+ where
+ -- The outer loop repeatedly slurps the decls for the current gates
+ -- and the instance decls
+
+ -- The outer loop is needed because consider
+
+ go_outer decls fvs all_gates []
+ = returnRn (decls, fvs)
+
+ go_outer decls fvs all_gates refs -- refs are not necessarily slurped yet
+ = traceRn (text "go_outer" <+> ppr refs) `thenRn_`
+ foldlRn go_inner (decls, fvs, emptyFVs) refs `thenRn` \ (decls1, fvs1, gates1) ->
+ getImportedInstDecls (all_gates `plusFV` gates1) `thenRn` \ inst_decls ->
+ rnIfaceInstDecls decls1 fvs1 gates1 inst_decls `thenRn` \ (decls2, fvs2, gates2) ->
+ go_outer decls2 fvs2 (all_gates `plusFV` gates2)
+ (nameSetToList (gates2 `minusNameSet` all_gates))
+ -- Knock out the all_gates because even if we don't slurp any new
+ -- decls we can get some apparently-new gates from wired-in names
+
+ go_inner (decls, fvs, gates) wanted_name
+ = importDecl wanted_name `thenRn` \ import_result ->
+ case import_result of
+ AlreadySlurped -> returnRn (decls, fvs, gates)
+ InTypeEnv ty_thing -> returnRn (decls, fvs, gates `plusFV` getWiredInGates ty_thing)
+
+ HereItIs decl -> rnIfaceTyClDecl decl `thenRn` \ (new_decl, fvs1) ->
+ returnRn (TyClD new_decl : decls,
+ fvs1 `plusFV` fvs,
+ gates `plusFV` getGates source_fvs new_decl)
+\end{code}
-%*********************************************************
-%* *
-\subsection{Getting in a declaration}
-%* *
-%*********************************************************
\begin{code}
-getDecl :: Name -> RnMG (AvailInfo, RdrNameHsDecl)
-getDecl name
- = traceRn doc_str `thenRn_`
- loadInterface doc_str mod `thenRn` \ (Ifaces _ _ _ _ decls_map _ _) ->
- case lookupFM decls_map name of
+-------------------------------------------------------
+-- closeDecls keeps going until the free-var set is empty
+closeDecls decls needed
+ | not (isEmptyFVs needed)
+ = slurpDecls decls needed `thenRn` \ (decls1, needed1) ->
+ closeDecls decls1 needed1
+
+ | otherwise
+ = getImportedRules `thenRn` \ rule_decls ->
+ case rule_decls of
+ [] -> returnRn decls -- No new rules, so we are done
+ other -> rnIfaceDecls rnIfaceRuleDecl rule_decls `thenRn` \ rule_decls' ->
+ let
+ rule_fvs = plusFVs (map ruleDeclFVs rule_decls')
+ in
+ traceRn (text "closeRules" <+> ppr rule_decls' $$ fsep (map ppr (nameSetToList rule_fvs))) `thenRn_`
+ closeDecls (map RuleD rule_decls' ++ decls) rule_fvs
+
+
+
+-------------------------------------------------------
+-- Augment decls with any decls needed by needed.
+-- Return also free vars of the new decls (only)
+slurpDecls decls needed
+ = go decls emptyFVs (nameSetToList needed)
+ where
+ go decls fvs [] = returnRn (decls, fvs)
+ go decls fvs (ref:refs) = slurpDecl decls fvs ref `thenRn` \ (decls1, fvs1) ->
+ go decls1 fvs1 refs
+
+-------------------------------------------------------
+slurpDecl decls fvs wanted_name
+ = importDecl wanted_name `thenRn` \ import_result ->
+ case import_result of
+ -- Found a declaration... rename it
+ HereItIs decl -> rnIfaceTyClDecl decl `thenRn` \ (new_decl, fvs1) ->
+ returnRn (TyClD new_decl:decls, fvs1 `plusFV` fvs)
+
+ -- No declaration... (wired in thing, or deferred, or already slurped)
+ other -> returnRn (decls, fvs)
+
+
+-------------------------------------------------------
+rnIfaceDecls rn decls = mapRn (rnIfaceDecl rn) decls
+rnIfaceDecl rn (mod, decl) = initIfaceRnMS mod (rn decl)
+
+rnIfaceInstDecls decls fvs gates inst_decls
+ = rnIfaceDecls rnInstDecl inst_decls `thenRn` \ inst_decls' ->
+ returnRn (map InstD inst_decls' ++ decls,
+ fvs `plusFV` plusFVs (map instDeclFVs inst_decls'),
+ gates `plusFV` plusFVs (map getInstDeclGates inst_decls'))
+
+rnIfaceTyClDecl (mod, decl) = initIfaceRnMS mod (rnTyClDecl decl) `thenRn` \ decl' ->
+ returnRn (decl', tyClDeclFVs decl')
+\end{code}
- Just avail_w_decl -> returnRn avail_w_decl
- Nothing -> -- Can happen legitimately for "Optional" occurrences
- returnRn (NotAvailable, ValD EmptyBinds)
+\begin{code}
+getSlurped
+ = getIfacesRn `thenRn` \ ifaces ->
+ returnRn (iSlurp ifaces)
+
+recordSlurp ifaces@(Ifaces { iDecls = (decls_map, n_slurped),
+ iSlurp = slurped_names,
+ iVSlurp = (imp_mods, imp_names) })
+ avail
+ = ASSERT2( not (isLocalName (availName avail)), ppr avail )
+ ifaces { iDecls = (decls_map', n_slurped+1),
+ iSlurp = new_slurped_names,
+ iVSlurp = new_vslurp }
where
- (mod,_) = modAndOcc name
- doc_str = ppSep [ppStr "Need decl for", ppr PprDebug name]
+ decls_map' = foldl delFromNameEnv decls_map (availNames avail)
+ main_name = availName avail
+ mod = nameModule main_name
+ new_slurped_names = addAvailToNameSet slurped_names avail
+ new_vslurp | isHomeModule mod = (imp_mods, addOneToNameSet imp_names main_name)
+ | otherwise = (extendModuleSet imp_mods mod, imp_names)
+
+recordLocalSlurps new_names
+ = getIfacesRn `thenRn` \ ifaces ->
+ setIfacesRn (ifaces { iSlurp = iSlurp ifaces `unionNameSets` new_names })
\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,
- * 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.
- * similarly for synonum type constructor
- * if the wired-in name is another wired-in Id, it marks as "occurrences"
- the free vars of the Id's type.
+%*********************************************************
+%* *
+\subsection{Extracting the `gates'}
+%* *
+%*********************************************************
+
+The gating story
+~~~~~~~~~~~~~~~~~
+We want to avoid sucking in too many instance declarations.
+An instance decl is only useful if the types and classes mentioned in
+its 'head' are all available in the program being compiled. E.g.
+
+ instance (..) => C (T1 a) (T2 b) where ...
+
+is only useful if C, T1 and T2 are all "available". So we keep
+instance decls that have been parsed from .hi files, but not yet
+slurped in, in a pool called the 'gated instance pool'.
+Each has its set of 'gates': {C, T1, T2} in the above example.
- * it loads the interface file for the wired-in thing for the
- sole purpose of making sure that its instance declarations are available
+More precisely, the gates of a module are the types and classes
+that are mentioned in:
-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.
+ a) the source code
+ b) the type of an Id that's mentioned in the source code
+ [includes constructors and selectors]
+ c) the RHS of a type synonym that is a gate
+ d) the superclasses of a class that is a gate
+ e) the context of an instance decl that is slurped in
+
+We slurp in an instance decl from the gated instance pool iff
+ all its gates are either in the gates of the module,
+ or are a previously-loaded class.
+
+The latter constraint is because there might have been an instance
+decl slurped in during an earlier compilation, like this:
+
+ instance Foo a => Baz (Maybe a) where ...
+
+In the module being compiled we might need (Baz (Maybe T)), where T
+is defined in this module, and hence we need (Foo T). So @Foo@ becomes
+a gate. But there's no way to 'see' that, so we simply treat all
+previously-loaded classes as gates.
+
+Consructors and class operations
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+When we import a declaration like
+
+ data T = T1 Wibble | T2 Wobble
+
+we don't want to treat @Wibble@ and @Wobble@ as gates {\em unless}
+@T1@, @T2@ respectively are mentioned by the user program. If only
+@T@ is mentioned we want only @T@ to be a gate; that way we don't suck
+in useless instance decls for (say) @Eq Wibble@, when they can't
+possibly be useful.
+
+And that's just what (b) says: we only treat T1's type as a gate if
+T1 is mentioned. getGates, which deals with decls we are slurping in,
+has to be a bit careful, because a mention of T1 will slurp in T's whole
+declaration.
+
+-----------------------------
+@getGates@ takes a newly imported (and renamed) decl, and the free
+vars of the source program, and extracts from the decl the gate names.
+
\begin{code}
-getWiredInDecl :: Name -> RnMG AvailInfo
-getWiredInDecl name
- = -- Force in the home module in case it has instance decls for
- -- the thing we are interested in
- (if mod == gHC__ then
- returnRn () -- Mini hack; GHC is guaranteed not to have
- -- instance decls, so it's a waste of time
- -- to read it
- else
- loadInterface doc_str mod `thenRn_`
- returnRn ()
- ) `thenRn_`
-
- if (maybeToBool maybe_wired_in_tycon) then
- get_wired_tycon the_tycon
- else -- Must be a wired-in-Id
- if (isDataCon the_id) then -- ... a wired-in data constructor
- get_wired_tycon (dataConTyCon the_id)
- else -- ... a wired-in non data-constructor
- get_wired_id the_id
+getGates :: FreeVars -- Things mentioned in the source program
+ -> RenamedTyClDecl
+ -> FreeVars
+
+getGates source_fvs decl
+ = get_gates (\n -> n `elemNameSet` source_fvs) decl
+
+get_gates is_used (IfaceSig _ ty _ _)
+ = extractHsTyNames ty
+
+get_gates is_used (ClassDecl ctxt cls tvs _ sigs _ _ _ )
+ = (delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) sigs)
+ (hsTyVarNames tvs)
+ `addOneToNameSet` cls)
+ `plusFV` maybe_double
where
- doc_str = ppSep [ppStr "Need home module for wired in thing", ppr PprDebug name]
- (mod,_) = modAndOcc name
- maybe_wired_in_tycon = maybeWiredInTyConName name
- maybe_wired_in_id = maybeWiredInIdName name
- Just the_tycon = maybe_wired_in_tycon
- Just the_id = maybe_wired_in_id
-
-get_wired_id id
- = addImplicitOccsRn (nameSetToList id_mentioned) `thenRn_`
- returnRn (Avail (getName id) [])
+ get (ClassOpSig n _ ty _)
+ | is_used n = extractHsTyNames ty
+ | otherwise = emptyFVs
+
+ -- If we load any numeric class that doesn't have
+ -- Int as an instance, add Double to the gates.
+ -- This takes account of the fact that Double might be needed for
+ -- defaulting, but we don't want to load Double (and all its baggage)
+ -- if the more exotic classes aren't used at all.
+ maybe_double | nameUnique cls `elem` fractionalClassKeys
+ = unitFV (getName doubleTyCon)
+ | otherwise
+ = emptyFVs
+
+get_gates is_used (TySynonym tycon tvs ty _)
+ = delListFromNameSet (extractHsTyNames ty) (hsTyVarNames tvs)
+ -- A type synonym type constructor isn't a "gate" for instance decls
+
+get_gates is_used (TyData _ ctxt tycon tvs cons _ _ _ _ _)
+ = delListFromNameSet (foldr (plusFV . get) (extractHsCtxtTyNames ctxt) cons)
+ (hsTyVarNames tvs)
+ `addOneToNameSet` tycon
where
- id_mentioned = namesOfType (idType id)
+ get (ConDecl n _ tvs ctxt details _)
+ | is_used n
+ -- If the constructor is method, get fvs from all its fields
+ = delListFromNameSet (get_details details `plusFV`
+ extractHsCtxtTyNames ctxt)
+ (hsTyVarNames tvs)
+ get (ConDecl n _ tvs ctxt (RecCon fields) _)
+ -- Even if the constructor isn't mentioned, the fields
+ -- might be, as selectors. They can't mention existentially
+ -- bound tyvars (typechecker checks for that) so no need for
+ -- the deleteListFromNameSet part
+ = foldr (plusFV . get_field) emptyFVs fields
+
+ get other_con = emptyFVs
-get_wired_tycon tycon
- | isSynTyCon tycon
- = addImplicitOccsRn (nameSetToList mentioned) `thenRn_`
- returnRn (Avail (getName tycon) [])
- where
- (tyvars,ty) = getSynTyConDefn tycon
- mentioned = namesOfType ty `minusNameSet` mkNameSet (map getName tyvars)
+ get_details (VanillaCon tys) = plusFVs (map get_bang tys)
+ get_details (InfixCon t1 t2) = get_bang t1 `plusFV` get_bang t2
+ get_details (RecCon fields) = plusFVs [get_bang t | (_, t) <- fields]
-get_wired_tycon tycon
- | otherwise -- data or newtype
- = addImplicitOccsRn (nameSetToList mentioned) `thenRn_`
- returnRn (Avail (getName tycon) (map getName data_cons))
- where
- data_cons = tyConDataCons tycon
- mentioned = foldr (unionNameSets . namesOfType . idType) emptyNameSet data_cons
-\end{code}
+ get_field (fs,t) | any is_used fs = get_bang t
+ | otherwise = emptyFVs
+ get_bang bty = extractHsTyNames (getBangType bty)
+\end{code}
-%*********************************************************
-%* *
-\subsection{Getting other stuff}
-%* *
-%*********************************************************
+@getWiredInGates@ is just like @getGates@, but it sees a previously-loaded
+thing rather than a declaration.
\begin{code}
-getInterfaceExports :: Module -> RnMG (Avails, [(OccName,Fixity)])
-getInterfaceExports mod
- = loadInterface doc_str mod `thenRn` \ (Ifaces _ _ export_envs _ _ _ _) ->
- case lookupFM export_envs mod 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 ([],[])
-
- Just stuff -> returnRn stuff
+getWiredInGates :: TyThing -> FreeVars
+-- The TyThing is one that we already have in our type environment, either
+-- a) because the TyCon or Id is wired in, or
+-- b) from a previous compile
+-- Either way, we might have instance decls in the (persistent) collection
+-- of parsed-but-not-slurped instance decls that should be slurped in.
+-- This might be the first module that mentions both the type and the class
+-- for that instance decl, even though both the type and the class were
+-- mentioned in other modules, and hence are in the type environment
+
+getWiredInGates (AnId the_id) = namesOfType (idType the_id)
+getWiredInGates (AClass cl) = emptyFVs -- The superclasses must also be previously
+ -- loaded, and hence are automatically gates
+getWiredInGates (ATyCon tc)
+ | isSynTyCon tc = delListFromNameSet (namesOfType ty) (map getName tyvars)
+ | otherwise = unitFV (getName tc)
where
- doc_str = ppSep [pprModule PprDebug mod, ppStr "is directly imported"]
+ (tyvars,ty) = getSynTyConDefn tc
+getInstDeclGates (InstDecl inst_ty _ _ _ _) = extractHsTyNames inst_ty
+\end{code}
-getImportedInstDecls :: RnMG [IfaceInst]
-getImportedInstDecls
- = -- First load any special-instance modules that aren't aready loaded
- getSpecialInstModules `thenRn` \ inst_mods ->
- mapRn load_it inst_mods `thenRn_`
+\begin{code}
+getImportedInstDecls :: NameSet -> RnMG [(Module,RdrNameInstDecl)]
+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, _)) <- fmToList (iImpModInfo ifaces)]
+ in
+ loadOrphanModules orphan_mods `thenRn_`
-- Now we're ready to grab the instance declarations
- getIfacesRn `thenRn` \ ifaces ->
+ -- Find the un-gated ones and return them,
+ -- removing them from the bag kept in Ifaces
+ getIfacesRn `thenRn` \ ifaces ->
+ getTypeEnvRn `thenRn` \ lookup ->
let
- Ifaces _ _ _ _ _ insts _ = ifaces
+ (decls, new_insts) = selectGated gates lookup (iInsts ifaces)
in
- returnRn (bagToList insts)
- where
- load_it mod = loadInterface (doc_str mod) mod
- doc_str mod = ppSep [pprModule PprDebug mod, ppStr "is a special-instance module"]
+ setIfacesRn (ifaces { iInsts = new_insts }) `thenRn_`
-getSpecialInstModules :: RnMG [Module]
-getSpecialInstModules
- = getIfacesRn `thenRn` \ ifaces ->
+ 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, InstDecl inst_ty _ _ _ _)
+ = case inst_ty of
+ HsForAllTy _ _ tau -> ppr tau
+ other -> ppr inst_ty
+
+getImportedRules :: RnMG [(Module,RdrNameRuleDecl)]
+getImportedRules
+ | opt_IgnoreIfacePragmas = returnRn []
+ | otherwise
+ = getIfacesRn `thenRn` \ ifaces ->
+ getTypeEnvRn `thenRn` \ lookup ->
let
- Ifaces _ _ _ _ _ _ inst_mods = ifaces
+ gates = iSlurp ifaces -- Anything at all that's been slurped
+ rules = iRules ifaces
+ (decls, new_rules) = selectGated gates lookup rules
in
- returnRn inst_mods
-\end{code}
+ if null decls then
+ returnRn []
+ else
+ setIfacesRn (ifaces { iRules = new_rules }) `thenRn_`
+ traceRn (sep [text "getImportedRules:",
+ text "Slurped" <+> int (length decls) <+> text "rules"]) `thenRn_`
+ returnRn decls
+
+selectGated gates lookup (decl_bag, n_slurped)
+ -- Select only those decls whose gates are *all* in 'gates'
+ -- or are a class in 'lookup'
+#ifdef DEBUG
+ | opt_NoPruneDecls -- Just to try the effect of not gating at all
+ = let
+ decls = foldrBag (\ (_,d) ds -> d:ds) [] decl_bag -- Grab them all
+ in
+ (decls, (emptyBag, n_slurped + length decls))
-\begin{code}
-getImportVersions :: [AvailInfo] -- Imported avails
- -> RnMG (VersionInfo Name) -- Version info for these names
+ | otherwise
+#endif
+ = case foldrBag select ([], emptyBag) decl_bag of
+ (decls, new_bag) -> (decls, (new_bag, n_slurped + length decls))
+ where
+ available n = n `elemNameSet` gates
+ || case lookup n of { Just (AClass c) -> True; other -> False }
-getImportVersions imported_avails
- = getIfacesRn `thenRn` \ ifaces ->
- let
- Ifaces _ mod_versions_map _ version_map _ _ _ = ifaces
-
- -- import_versions is harder: we have to group together all the things imported
- -- from a particular module. We do this with yet another finite map
-
- mv_map :: FiniteMap Module [LocalVersion Name]
- mv_map = foldl add_mv emptyFM imported_avails
- add_mv mv_map (Avail name _)
- | isWiredInName name = mv_map -- Don't record versions for wired-in names
- | otherwise = case lookupFM mv_map mod of
- Just versions -> addToFM mv_map mod ((name,version):versions)
- Nothing -> addToFM mv_map mod [(name,version)]
- where
- (mod,_) = modAndOcc name
- version = case lookupFM version_map name of
- Just v -> v
- Nothing -> pprPanic "getVersionInfo:" (ppr PprDebug name)
-
- import_versions = [ (mod, expectJust "import_versions" (lookupFM mod_versions_map mod), local_versions)
- | (mod, local_versions) <- fmToList mv_map
- ]
-
- -- Question: should we filter the builtins out of import_versions?
- in
- returnRn import_versions
+ select (reqd, decl) (yes, no)
+ | all available reqd = (decl:yes, no)
+ | otherwise = (yes, (reqd,decl) `consBag` no)
\end{code}
+
%*********************************************************
%* *
-\subsection{Getting binders out of a declaration}
+\subsection{Getting in a declaration}
%* *
%*********************************************************
-@getDeclBinders@ returns the names for a @RdrNameHsDecl@.
-It's used for both source code (from @availsFromDecl@) and interface files
-(from @loadDecl@).
+\begin{code}
+importDecl :: Name -> RnMG ImportDeclResult
+
+data ImportDeclResult
+ = AlreadySlurped
+ | InTypeEnv TyThing
+ | HereItIs (Module, RdrNameTyClDecl)
+
+importDecl name
+ = -- STEP 1: Check if we've slurped it in while compiling this module
+ getIfacesRn `thenRn` \ ifaces ->
+ if name `elemNameSet` iSlurp ifaces then
+ returnRn AlreadySlurped
+ else
+
+ -- STEP 2: Check if it's already in the type environment
+ getTypeEnvRn `thenRn` \ lookup ->
+ case lookup name of {
+ Just ty_thing | name `elemNameEnv` wiredInThingEnv
+ -> -- When we find a wired-in name we must load its home
+ -- module so that we find any instance decls lurking therein
+ loadHomeInterface wi_doc name `thenRn_`
+ returnRn (InTypeEnv ty_thing)
-It doesn't deal with source-code specific things: ValD, DefD. They
-are handled by the sourc-code specific stuff in RnNames.
+ | otherwise
+ -> returnRn (InTypeEnv ty_thing) ;
-\begin{code}
-getDeclBinders :: (RdrName -> SrcLoc -> RnMG Name) -- New-name function
- -> RdrNameHsDecl
- -> RnMG AvailInfo
-
-getDeclBinders new_name (TyD (TyData _ tycon _ condecls _ _ src_loc))
- = new_name tycon src_loc `thenRn` \ tycon_name ->
- getConFieldNames new_name condecls `thenRn` \ sub_names ->
- returnRn (Avail tycon_name sub_names)
-
-getDeclBinders new_name (TyD (TyNew _ tycon _ (NewConDecl con _ con_loc) _ _ src_loc))
- = new_name tycon src_loc `thenRn` \ tycon_name ->
- new_name con src_loc `thenRn` \ con_name ->
- returnRn (Avail tycon_name [con_name])
-
-getDeclBinders new_name (TyD (TySynonym tycon _ _ src_loc))
- = new_name tycon src_loc `thenRn` \ tycon_name ->
- returnRn (Avail tycon_name [])
-
-getDeclBinders new_name (ClD (ClassDecl _ cname _ sigs _ _ src_loc))
- = new_name cname src_loc `thenRn` \ class_name ->
- mapRn (getClassOpNames new_name) sigs `thenRn` \ sub_names ->
- returnRn (Avail class_name sub_names)
-
-getDeclBinders new_name (SigD (IfaceSig var ty prags src_loc))
- = new_name var src_loc `thenRn` \ var_name ->
- returnRn (Avail var_name [])
-
-getDeclBinders new_name (DefD _) = returnRn NotAvailable
-getDeclBinders new_name (InstD _) = returnRn NotAvailable
-
-----------------
-getConFieldNames new_name (ConDecl con _ src_loc : rest)
- = new_name con src_loc `thenRn` \ n ->
- getConFieldNames new_name rest `thenRn` \ ns ->
- returnRn (n:ns)
-
-getConFieldNames new_name (NewConDecl con _ src_loc : rest)
- = new_name con src_loc `thenRn` \ n ->
- getConFieldNames new_name rest `thenRn` \ ns ->
- returnRn (n:ns)
-
-getConFieldNames new_name (ConOpDecl _ con _ src_loc : rest)
- = new_name con src_loc `thenRn` \ n ->
- getConFieldNames new_name rest `thenRn` \ ns ->
- returnRn (n:ns)
-
-getConFieldNames new_name (RecConDecl con 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)
+ Nothing ->
+
+ -- STEP 3: OK, we have to slurp it in from an interface file
+ -- First load the interface file
+ traceRn nd_doc `thenRn_`
+ loadHomeInterface nd_doc name `thenRn_`
+ getIfacesRn `thenRn` \ ifaces ->
-getConFieldNames new_name [] = returnRn []
+ -- STEP 4: Get the declaration out
+ let
+ (decls_map, _) = iDecls ifaces
+ in
+ case lookupNameEnv decls_map name of
+ Just (avail,_,decl)
+ -> setIfacesRn (recordSlurp ifaces avail) `thenRn_`
+ returnRn (HereItIs decl)
+
+ Nothing
+ -> addErrRn (getDeclErr name) `thenRn_`
+ returnRn AlreadySlurped
+ }
+ where
+ wi_doc = ptext SLIT("need home module for wired in thing") <+> ppr name
+ nd_doc = ptext SLIT("need decl for") <+> ppr name
-getClassOpNames new_name (ClassOpSig op _ _ src_loc) = new_name op src_loc
\end{code}
-%*********************************************************
+%********************************************************
%* *
-\subsection{Reading an interface file}
+\subsection{Checking usage information}
%* *
-%*********************************************************
+%********************************************************
+
+@recompileRequired@ is called from the HscMain. It checks whether
+a recompilation is required. It needs access to the persistent state,
+finder, etc, because it may have to load lots of interface files to
+check their versions.
\begin{code}
-findAndReadIface :: Pretty -> Module -> RnMG (Maybe ParsedIface)
- -- Nothing <=> file not found, or unreadable, or illegible
- -- Just x <=> successfully found and parsed
-findAndReadIface doc_str mod
- = traceRn trace_msg `thenRn_`
- getSearchPathRn `thenRn` \ dirs ->
- try dirs dirs
- where
- trace_msg = ppHang (ppBesides [ppStr "Reading interface for ",
- pprModule PprDebug mod, ppSemi])
- 4 (ppBesides [ppStr "reason: ", doc_str])
-
- try all_dirs [] = traceRn (ppStr "...failed") `thenRn_`
- returnRn Nothing
-
- try all_dirs (dir:dirs)
- = readIface file_path `thenRn` \ read_result ->
- case read_result of
- Nothing -> try all_dirs dirs
- Just iface -> traceRn (ppStr "...done") `thenRn_`
- returnRn (Just iface)
- where
- file_path = dir ++ "/" ++ moduleString mod ++ ".hi"
-\end{code}
+type RecompileRequired = Bool
+upToDate = False -- Recompile not required
+outOfDate = True -- Recompile required
+
+recompileRequired :: FilePath -- Only needed for debug msgs
+ -> Bool -- Source unchanged
+ -> ModIface -- Old interface
+ -> RnMG RecompileRequired
+recompileRequired iface_path source_unchanged iface
+ = traceHiDiffsRn (text "Considering whether compilation is required for" <+> text iface_path <> colon) `thenRn_`
+
+ -- CHECK WHETHER THE SOURCE HAS CHANGED
+ if not source_unchanged then
+ traceHiDiffsRn (nest 4 (text "Source file changed or recompilation check turned off")) `thenRn_`
+ returnRn outOfDate
+ else
-@readIface@ trys just one file.
+ -- Source code unchanged and no errors yet... carry on
+ checkList [checkModUsage u | u <- mi_usages iface]
+checkList :: [RnMG RecompileRequired] -> RnMG RecompileRequired
+checkList [] = returnRn upToDate
+checkList (check:checks) = check `thenRn` \ recompile ->
+ if recompile then
+ returnRn outOfDate
+ else
+ checkList checks
+\end{code}
+
\begin{code}
-readIface :: String -> RnMG (Maybe ParsedIface)
- -- Nothing <=> file not found, or unreadable, or illegible
- -- Just x <=> successfully found and parsed
-readIface file_path
- = ioToRnMG (readFile file_path) `thenRn` \ read_result ->
- case read_result of
- Right contents -> case parseIface contents of
- Failed err -> failWithRn Nothing err
- Succeeded iface -> returnRn (Just iface)
+checkModUsage :: ImportVersion Name -> RnMG RecompileRequired
+-- Given the usage information extracted from the old
+-- M.hi file for the module being compiled, figure out
+-- whether M needs to be recompiled.
+
+checkModUsage (mod_name, _, _, NothingAtAll)
+ -- 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.
+ = up_to_date (ptext SLIT("Nothing used from:") <+> ppr mod_name)
+
+checkModUsage (mod_name, _, is_boot, whats_imported)
+ = -- Load the imported interface is possible
+ -- We use tryLoadInterface, because failure is not an error
+ -- (might just be that the old .hi file for this module is out of date)
+ -- We use ImportByUser/ImportByUserSource as the 'from' flag,
+ -- a) because we need to know whether to load the .hi-boot file
+ -- b) because loadInterface things matters are amiss if we
+ -- ImportBySystem an interface it knows nothing about
+ let
+ doc_str = sep [ptext SLIT("need version info for"), ppr mod_name]
+ from | is_boot = ImportByUserSource
+ | otherwise = ImportByUser
+ in
+ tryLoadInterface doc_str mod_name from `thenRn` \ (iface, maybe_err) ->
- Left (NoSuchThing _) -> returnRn Nothing
+ case maybe_err of {
+ Just err -> out_of_date (sep [ptext SLIT("Can't find version number for module"),
+ ppr mod_name]) ;
+ -- 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
- Left err -> failWithRn Nothing
- (cannaeReadFile file_path err)
+ Nothing ->
+ let
+ new_vers = mi_version iface
+ new_decl_vers = vers_decls new_vers
+ in
+ case whats_imported of { -- NothingAtAll dealt with earlier
-\end{code}
+ Everything old_mod_vers -> checkModuleVersion old_mod_vers new_vers `thenRn` \ recompile ->
+ if recompile then
+ out_of_date (ptext SLIT("...and I needed the whole module"))
+ else
+ returnRn upToDate ;
-mkSearchPath takes a string consisting of a colon-separated list of directories, and turns it into
-a list of directories. For example:
+ Specifically old_mod_vers maybe_old_export_vers old_decl_vers old_rule_vers ->
- mkSearchPath "foo:.:baz" = ["foo", ".", "baz"]
+ -- CHECK MODULE
+ checkModuleVersion old_mod_vers new_vers `thenRn` \ recompile ->
+ if not recompile then
+ returnRn upToDate
+ else
+
+ -- CHECK EXPORT LIST
+ if checkExportList maybe_old_export_vers new_vers then
+ out_of_date (ptext SLIT("Export list changed"))
+ else
-\begin{code}
-mkSearchPath :: Maybe String -> SearchPath
-mkSearchPath Nothing = ["."]
-mkSearchPath (Just s)
- = go s
- where
- go "" = []
- go s = first : go (drop 1 rest)
- where
- (first,rest) = span (/= ':') s
+ -- CHECK RULES
+ if old_rule_vers /= vers_rules new_vers then
+ out_of_date (ptext SLIT("Rules changed"))
+ else
+
+ -- CHECK ITEMS ONE BY ONE
+ checkList [checkEntityUsage new_decl_vers u | u <- old_decl_vers] `thenRn` \ recompile ->
+ if recompile then
+ returnRn outOfDate -- This one failed, so just bail out now
+ else
+ up_to_date (ptext SLIT("...but the bits I use haven't."))
+
+ }}
+
+------------------------
+checkModuleVersion old_mod_vers new_vers
+ | vers_module new_vers == old_mod_vers
+ = up_to_date (ptext SLIT("Module version unchanged"))
+
+ | otherwise
+ = out_of_date (ptext SLIT("Module version has changed"))
+
+------------------------
+checkExportList Nothing new_vers = upToDate
+checkExportList (Just v) new_vers = v /= vers_exports new_vers
+
+------------------------
+checkEntityUsage new_vers (name,old_vers)
+ = case lookupNameEnv new_vers name of
+
+ Nothing -> -- We used it before, but it ain't there now
+ out_of_date (sep [ptext SLIT("No longer exported:"), ppr name])
+
+ Just new_vers -- It's there, but is it up to date?
+ | new_vers == old_vers -> returnRn upToDate
+ | otherwise -> out_of_date (sep [ptext SLIT("Out of date:"), ppr name])
+
+up_to_date msg = traceHiDiffsRn msg `thenRn_` returnRn upToDate
+out_of_date msg = traceHiDiffsRn msg `thenRn_` returnRn outOfDate
\end{code}
+
%*********************************************************
-%* *
+%* *
\subsection{Errors}
-%* *
+%* *
%*********************************************************
\begin{code}
-noIfaceErr mod sty
- = ppBesides [ppStr "Could not find interface for ", ppQuote (pprModule sty mod)]
--- , ppStr " in"]) 4 (ppAboves (map ppStr dirs))
-
-cannaeReadFile file err sty
- = ppBesides [ppPStr SLIT("Failed in reading file: "), ppStr file, ppStr "; error=", ppStr (show err)]
+getDeclErr name
+ = vcat [ptext SLIT("Failed to find interface decl for") <+> quotes (ppr name),
+ ptext SLIT("from module") <+> quotes (ppr (nameModule name))
+ ]
\end{code}
projects / ghc-hetmet.git / blobdiff