-%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
-%
-\section[RnNames]{Extracting imported and top-level names in scope}
-
-\begin{code}
-#include "HsVersions.h"
-
-module RnNames (
- getGlobalNames
- ) where
-
-IMP_Ubiq()
-
-import CmdLineOpts ( opt_SourceUnchanged )
-import HsSyn ( HsModule(..), HsDecl(..), FixityDecl(..), Fixity, Fake, InPat, IE(..), HsTyVar,
- TyDecl, ClassDecl, InstDecl, DefaultDecl, ImportDecl(..), HsBinds, IfaceSig
- )
-import HsBinds ( collectTopBinders )
-import HsImpExp ( ieName )
-import RdrHsSyn ( RdrNameHsDecl(..), RdrName(..), RdrNameIE(..), SYN_IE(RdrNameImportDecl),
- SYN_IE(RdrNameHsModule), SYN_IE(RdrNameFixityDecl),
- rdrNameOcc
- )
-import RnHsSyn ( RenamedHsModule(..), RenamedFixityDecl(..) )
-import RnIfaces ( getInterfaceExports, getDeclBinders, checkUpToDate )
-import RnEnv
-import RnMonad
-import FiniteMap
-import PrelMods
-import UniqFM ( UniqFM, emptyUFM, addListToUFM_C, lookupUFM )
-import Bag ( Bag, bagToList )
-import Maybes ( maybeToBool, expectJust )
-import Name
-import Pretty
-import PprStyle ( PprStyle(..) )
-import Util ( panic, pprTrace )
-\end{code}
-
-
-
-%************************************************************************
-%* *
-\subsection{Get global names}
-%* *
-%************************************************************************
-
-\begin{code}
-getGlobalNames :: RdrNameHsModule
- -> RnMG (Maybe (ExportEnv, RnEnv, [AvailInfo]))
- -- Nothing <=> no need to recompile
-
-getGlobalNames m@(HsModule this_mod _ exports imports _ _ mod_loc)
- = fixRn (\ ~(rec_exp_fn, _) ->
-
- -- PROCESS LOCAL DECLS
- -- Do these *first* so that the correct provenance gets
- -- into the global name cache.
- importsFromLocalDecls rec_exp_fn m `thenRn` \ (local_rn_env, local_mod_avails) ->
-
- -- PROCESS IMPORT DECLS
- mapAndUnzipRn importsFromImportDecl all_imports
- `thenRn` \ (imp_rn_envs, imp_avails_s) ->
-
- -- CHECK FOR EARLY EXIT
- checkEarlyExit this_mod `thenRn` \ early_exit ->
- if early_exit then
- returnRn (junk_exp_fn, Nothing)
- else
-
- -- COMBINE RESULTS
- -- We put the local env first, so that a local provenance
- -- "wins", even if a module imports itself.
- foldlRn plusRnEnv emptyRnEnv imp_rn_envs `thenRn` \ imp_rn_env ->
- plusRnEnv local_rn_env imp_rn_env `thenRn` \ rn_env ->
- let
- all_avails :: ModuleAvails
- all_avails = foldr plusModuleAvails local_mod_avails imp_avails_s
- local_avails = expectJust "getGlobalNames" (lookupModuleAvails local_mod_avails this_mod)
- in
-
- -- PROCESS EXPORT LISTS
- exportsFromAvail this_mod exports all_avails rn_env
- `thenRn` \ (export_fn, export_env) ->
-
- returnRn (export_fn, Just (export_env, rn_env, local_avails))
- ) `thenRn` \ (_, result) ->
- returnRn result
- where
- junk_exp_fn = error "RnNames:export_fn"
-
- all_imports = prel_imports ++ imports
-
- prel_imports | this_mod == pRELUDE ||
- explicit_prelude_import = []
-
- | otherwise = [ImportDecl pRELUDE
- False {- Not qualified -}
- Nothing {- No "as" -}
- Nothing {- No import list -}
- mod_loc]
-
- explicit_prelude_import
- = not (null [ () | (ImportDecl mod qual _ _ _) <- imports, mod == pRELUDE ])
-\end{code}
-
-\begin{code}
-checkEarlyExit mod
- = if not opt_SourceUnchanged then
- -- Source code changed; look no further
- returnRn False
- else
- -- Unchanged source; look further
- -- We check for
- -- (a) errors so far. These can arise if a module imports
- -- something that's no longer exported by the imported module
- -- (b) usage information up to date
- checkErrsRn `thenRn` \ no_errs_so_far ->
- checkUpToDate mod `thenRn` \ up_to_date ->
- returnRn (no_errs_so_far && up_to_date)
-\end{code}
-
-
-\begin{code}
-importsFromImportDecl :: RdrNameImportDecl
- -> RnMG (RnEnv, ModuleAvails)
-
- -- Check for "import M ()", and then don't even look at M.
- -- This makes sense, and is actually rather useful for the Prelude.
-importsFromImportDecl (ImportDecl mod qual as_mod (Just (False,[])) loc)
- = returnRn (emptyRnEnv, emptyModuleAvails)
-
-importsFromImportDecl (ImportDecl mod qual as_mod import_spec loc)
- = pushSrcLocRn loc $
- getInterfaceExports mod `thenRn` \ (avails, fixities) ->
- filterImports mod import_spec avails `thenRn` \ filtered_avails ->
- let
- filtered_avails' = [ Avail (set_name_prov n) (map set_name_prov ns)
- | Avail n ns <- filtered_avails
- ]
- fixities' = [ (occ,fixity,provenance) | (occ,fixity) <- fixities ]
- in
- qualifyImports mod qual as_mod (ExportEnv filtered_avails' fixities')
- where
- set_name_prov name = setNameProvenance name provenance
- provenance = Imported mod loc
-\end{code}
-
-
-\begin{code}
-importsFromLocalDecls rec_exp_fn (HsModule mod _ _ _ fix_decls decls _)
- = foldlRn getLocalDeclBinders [] decls `thenRn` \ avails ->
- mapRn fixityFromFixDecl fix_decls `thenRn` \ fixities ->
- qualifyImports mod
- False -- Not qualified
- Nothing -- No "as M" part
- (ExportEnv avails fixities)
- where
- newLocalName rdr_name loc
- = newLocallyDefinedGlobalName mod (rdrNameOcc rdr_name) rec_exp_fn loc
-
- getLocalDeclBinders avails (ValD binds)
- = mapRn do_one (bagToList (collectTopBinders binds)) `thenRn` \ val_avails ->
- returnRn (val_avails ++ avails)
-
- getLocalDeclBinders avails decl
- = getDeclBinders newLocalName decl `thenRn` \ avail ->
- returnRn (avail : avails)
-
- do_one (rdr_name, loc)
- = newLocalName rdr_name loc `thenRn` \ name ->
- returnRn (Avail name [])
-\end{code}
-
-%************************************************************************
-%* *
-\subsection{Filtering imports}
-%* *
-%************************************************************************
-
-@filterImports@ takes the @ExportEnv@ telling what the imported module makes
-available, and filters it through the import spec (if any).
-
-\begin{code}
-filterImports :: Module
- -> Maybe (Bool, [RdrNameIE]) -- Import spec; True => hidin
- -> [AvailInfo] -- What's available
- -> RnMG [AvailInfo] -- What's actually imported
- -- Complains if import spec mentions things the
- -- module doesn't export
-
-filterImports mod Nothing imports
- = returnRn imports
-
-filterImports mod (Just (want_hiding, import_items)) avails
- = -- Check that each import item mentions things that are actually available
- mapRn check_import_item import_items `thenRn_`
-
- -- Return filtered environment; no need to filter fixities
- returnRn (map new_avail avails)
-
- where
- import_fm :: FiniteMap OccName RdrNameIE
- import_fm = listToFM [(ieOcc ie, ie) | ie <- import_items]
-
- avail_fm :: FiniteMap OccName AvailInfo
- avail_fm = listToFM [(nameOccName name, avail) | avail@(Avail name ns) <- avails]
-
- new_avail NotAvailable = NotAvailable
- new_avail avail@(Avail name _)
- | not in_import_items && want_hiding = avail
- | not in_import_items && not want_hiding = NotAvailable
- | in_import_items && want_hiding = NotAvailable
- | in_import_items && not want_hiding = filtered_avail
- where
- maybe_import_item = lookupFM import_fm (nameOccName name)
- in_import_items = maybeToBool maybe_import_item
- Just import_item = maybe_import_item
- filtered_avail = filterAvail import_item avail
-
- check_import_item :: RdrNameIE -> RnMG ()
- check_import_item item
- = checkRn (maybeToBool maybe_matching_avail && sub_names_ok item avail)
- (badImportItemErr mod item)
- where
- item_name = ieOcc item
- maybe_matching_avail = lookupFM avail_fm item_name
- Just avail = maybe_matching_avail
-
- sub_names_ok (IEVar _) _ = True
- sub_names_ok (IEThingAbs _) _ = True
- sub_names_ok (IEThingAll _) _ = True
- sub_names_ok (IEThingWith _ wanted) (Avail _ has) = all ((`elem` has_list) . rdrNameOcc) wanted
- where
- has_list = map nameOccName has
- sub_names_ok other1 other2 = False
-\end{code}
-
-
-
-%************************************************************************
-%* *
-\subsection{Qualifiying imports}
-%* *
-%************************************************************************
-
-@qualifyImports@ takes the @ExportEnv@ after filtering through the import spec
-of an import decl, and deals with producing an @RnEnv@ with the
-right qaulified names. It also turns the @Names@ in the @ExportEnv@ into
-fully fledged @Names@.
-
-\begin{code}
-qualifyImports :: Module -- Improrted module
- -> Bool -- True <=> qualified import
- -> Maybe Module -- Optional "as M" part
- -> ExportEnv -- What's imported
- -> RnMG (RnEnv, ModuleAvails)
-
-qualifyImports this_mod qual as_mod (ExportEnv avails fixities)
- = -- Make the qualified-name environments, checking of course for clashes
- foldlRn add_name emptyNameEnv avails `thenRn` \ name_env ->
- foldlRn (add_fixity name_env) emptyFixityEnv fixities `thenRn` \ fixity_env ->
-
- -- Deal with the "qualified" part; if not qualifies then add unqualfied bindings
- if qual then
- returnRn (RnEnv name_env fixity_env, mod_avail_env)
- else
- returnRn (RnEnv (unQualify name_env) (unQualify fixity_env), mod_avail_env)
-
- where
- mod_avail_env = unitFM this_mod avails
-
- add_name name_env NotAvailable = returnRn name_env
- add_name name_env (Avail n ns) = foldlRn add_one name_env (n : ns)
-
- add_one :: NameEnv -> Name -> RnMG NameEnv
- add_one env name = addOneToNameEnvRn env (Qual this_mod occ_name) name
- where
- occ_name = nameOccName name
-
- add_fixity name_env fixity_env (occ_name, fixity, provenance)
- | maybeToBool (lookupFM name_env qual_name) -- The name is imported
- = addOneToFixityEnvRn fixity_env qual_name (fixity,provenance)
- | otherwise -- It ain't imported
- = returnRn fixity_env
- where
- qual_name = Qual this_mod occ_name
-\end{code}
-
-unQualify adds an Unqual binding for every existing Qual binding.
-
-\begin{code}
-unQualify :: FiniteMap RdrName elt -> FiniteMap RdrName elt
-unQualify fm = addListToFM fm [(Unqual occ, elt) | (Qual _ occ, elt) <- fmToList fm]
-\end{code}
-
-%************************************************************************
-%* *
-\subsection{Local declarations}
-%* *
-%************************************************************************
-
-
-\begin{code}
-fixityFromFixDecl :: RdrNameFixityDecl -> RnMG (OccName, Fixity, Provenance)
-
-fixityFromFixDecl (FixityDecl rdr_name fixity loc)
- = returnRn (rdrNameOcc rdr_name, fixity, LocalDef (panic "export-flag") loc)
-\end{code}
-
-
-%************************************************************************
-%* *
-\subsection{Export list processing
-%* *
-%************************************************************************
-
-The @AvailEnv@ type is just used internally in @exportsFromAvail@.
-When exporting we need to combine the availabilities for a particular
-exported thing, and we also need to check for name clashes -- that
-is: two exported things must have different @OccNames@.
-
-\begin{code}
-type AvailEnv = FiniteMap OccName (RdrNameIE, AvailInfo)
- -- The FM maps each OccName to the RdrNameIE that gave rise to it,
- -- for error reporting, as well as to its AvailInfo
-
-emptyAvailEnv = emptyFM
-
-unitAvailEnv :: RdrNameIE -> AvailInfo -> AvailEnv
-unitAvailEnv ie NotAvailable
- = emptyFM
-unitAvailEnv ie avail@(Avail n ns)
- = unitFM (nameOccName n) (ie,avail)
-
-plusAvailEnv a1 a2
- = mapRn (addErrRn.availClashErr) (conflictsFM bad_avail a1 a2) `thenRn_`
- returnRn (plusFM_C plus_avail a1 a2)
-
-listToAvailEnv :: RdrNameIE -> [AvailInfo] -> RnM s d AvailEnv
-listToAvailEnv ie items
- = foldlRn plusAvailEnv emptyAvailEnv (map (unitAvailEnv ie) items)
-
-bad_avail (ie1,Avail n1 _) (ie2,Avail n2 _) = n1 /= n2 -- Same OccName, different Name
-plus_avail (ie1,a1) (ie2,a2) = (ie1, a1 `plusAvail` a2)
-\end{code}
-
-
-\begin{code}
-exportsFromAvail :: Module
- -> Maybe [RdrNameIE] -- Export spec
- -> ModuleAvails
- -> RnEnv
- -> RnMG (Name -> ExportFlag, ExportEnv)
- -- Complains if two distinct exports have same OccName
- -- Complains about exports items not in scope
-exportsFromAvail this_mod Nothing all_avails rn_env
- = exportsFromAvail this_mod (Just [IEModuleContents this_mod]) all_avails rn_env
-
-exportsFromAvail this_mod (Just export_items) all_avails (RnEnv name_env fixity_env)
- = mapRn exports_from_item export_items `thenRn` \ avail_envs ->
- foldlRn plusAvailEnv emptyAvailEnv avail_envs `thenRn` \ export_avail_env ->
- let
- export_avails = map snd (eltsFM export_avail_env)
- export_fixities = mk_exported_fixities (availsToNameSet export_avails)
- export_fn = mk_export_fn export_avails
- in
- returnRn (export_fn, ExportEnv export_avails export_fixities)
-
- where
- full_avail_env :: UniqFM AvailInfo
- full_avail_env = addListToUFM_C plusAvail emptyUFM
- [(name,avail) | avail@(Avail name _) <- concat (eltsFM all_avails)]
- -- NB: full_avail_env won't contain bindings for data constructors and class ops,
- -- which is right and proper; attempts to export them on their own will provoke an error
-
- exports_from_item :: RdrNameIE -> RnMG AvailEnv
- exports_from_item ie@(IEModuleContents mod)
- = case lookupFM all_avails mod of
- Nothing -> failWithRn emptyAvailEnv (modExportErr mod)
- Just avails -> addOccurrenceNames Compulsory [n | Avail n _ <- avails] `thenRn_`
- listToAvailEnv ie avails
-
- exports_from_item ie
- | not (maybeToBool maybe_in_scope)
- = failWithRn emptyAvailEnv (unknownNameErr (ieName ie))
-
-#ifdef DEBUG
- -- I can't see why this should ever happen; if the thing is in scope
- -- at all it ought to have some availability
- | not (maybeToBool maybe_avail)
- = pprTrace "exportsFromAvail: curious Nothing:" (ppr PprDebug name)
- returnRn emptyAvailEnv
-#endif
-
- | not enough_avail
- = failWithRn emptyAvailEnv (exportItemErr ie export_avail)
-
- | otherwise -- Phew! It's OK!
- = addOccurrenceName Compulsory name `thenRn_`
- returnRn (unitAvailEnv ie export_avail)
- where
- maybe_in_scope = lookupNameEnv name_env (ieName ie)
- Just name = maybe_in_scope
- maybe_avail = lookupUFM full_avail_env name
- Just avail = maybe_avail
- export_avail = filterAvail ie avail
- enough_avail = case export_avail of {NotAvailable -> False; other -> True}
-
- -- We export a fixity iff we export a thing with the same (qualified) RdrName
- mk_exported_fixities :: NameSet -> [(OccName, Fixity, Provenance)]
- mk_exported_fixities exports
- = [ (rdrNameOcc rdr_name, fixity, prov)
- | (rdr_name, (fixity, prov)) <- fmToList fixity_env,
- export_fixity name_env exports rdr_name
- ]
-
-mk_export_fn :: [AvailInfo] -> (Name -> ExportFlag)
-mk_export_fn avails
- = \name -> if name `elemNameSet` exported_names
- then Exported
- else NotExported
- where
- exported_names :: NameSet
- exported_names = availsToNameSet avails
-
-export_fixity :: NameEnv -> NameSet -> RdrName -> Bool
-export_fixity name_env exports (Unqual _)
- = False -- The qualified fixity is always there as well
-export_fixity name_env exports rdr_name@(Qual _ occ)
- = case lookupFM name_env rdr_name of
- Just fixity_name -> fixity_name `elemNameSet` exports
- -- Check whether the exported thing is
- -- the one to which the fixity attaches
- other -> False -- Not even in scope
-\end{code}
-
-
-%************************************************************************
-%* *
-\subsection{Errors}
-%* *
-%************************************************************************
-
-\begin{code}
-ieOcc ie = rdrNameOcc (ieName ie)
-
-badImportItemErr mod ie sty
- = ppSep [ppStr "Module", pprModule sty mod, ppStr "does not export", ppr sty ie]
-
-modExportErr mod sty
- = ppCat [ ppStr "Unknown module in export list: module", ppPStr mod]
-
-exportItemErr export_item NotAvailable sty
- = ppSep [ ppStr "Export item not in scope:", ppr sty export_item ]
-
-exportItemErr export_item avail sty
- = ppHang (ppStr "Export item not fully in scope:")
- 4 (ppAboves [ppCat [ppStr "Wanted: ", ppr sty export_item],
- ppCat [ppStr "Available: ", ppr sty (ieOcc export_item), pprAvail sty avail]])
-
-availClashErr (occ_name, ((ie1,avail1), (ie2,avail2))) sty
- = ppHang (ppCat [ppStr "Conflicting exports for local name: ", ppr sty occ_name])
- 4 (ppAboves [ppr sty ie1, ppr sty ie2])
-\end{code}
-
+%\r
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998\r
+%\r
+\section[RnNames]{Extracting imported and top-level names in scope}\r
+\r
+\begin{code}\r
+module RnNames (\r
+ getGlobalNames\r
+ ) where\r
+\r
+#include "HsVersions.h"\r
+\r
+import CmdLineOpts ( opt_NoImplicitPrelude, opt_WarnDuplicateExports, \r
+ opt_SourceUnchanged, opt_WarnUnusedBinds\r
+ )\r
+\r
+import HsSyn ( HsModule(..), HsDecl(..), TyClDecl(..),\r
+ IE(..), ieName, \r
+ ForeignDecl(..), ForKind(..), isDynamic,\r
+ FixitySig(..), Sig(..), ImportDecl(..),\r
+ collectTopBinders\r
+ )\r
+import RdrHsSyn ( RdrNameIE, RdrNameImportDecl,\r
+ RdrNameHsModule, RdrNameHsDecl\r
+ )\r
+import RnIfaces ( getInterfaceExports, getDeclBinders,\r
+ recordSlurp, checkUpToDate\r
+ )\r
+import RnEnv\r
+import RnMonad\r
+\r
+import FiniteMap\r
+import PrelMods\r
+import PrelInfo ( main_RDR )\r
+import UniqFM ( lookupUFM )\r
+import Bag ( bagToList )\r
+import Maybes ( maybeToBool )\r
+import Module ( ModuleName, mkThisModule, pprModuleName, WhereFrom(..) )\r
+import NameSet\r
+import Name ( Name, ExportFlag(..), ImportReason(..), Provenance(..),\r
+ isLocallyDefined, setNameProvenance,\r
+ nameOccName, getSrcLoc, pprProvenance, getNameProvenance\r
+ )\r
+import RdrName ( RdrName, rdrNameOcc, mkRdrQual, mkRdrUnqual, isQual )\r
+import SrcLoc ( SrcLoc )\r
+import NameSet ( elemNameSet, emptyNameSet )\r
+import Outputable\r
+import Unique ( getUnique )\r
+import Util ( removeDups, equivClassesByUniq, sortLt )\r
+import List ( partition )\r
+\end{code}\r
+\r
+\r
+\r
+%************************************************************************\r
+%* *\r
+\subsection{Get global names}\r
+%* *\r
+%************************************************************************\r
+\r
+\begin{code}\r
+getGlobalNames :: RdrNameHsModule\r
+ -> RnMG (Maybe (ExportEnv, \r
+ GlobalRdrEnv,\r
+ FixityEnv, -- Fixities for local decls only\r
+ NameEnv AvailInfo -- Maps a name to its parent AvailInfo\r
+ -- Just for in-scope things only\r
+ ))\r
+ -- Nothing => no need to recompile\r
+\r
+getGlobalNames (HsModule this_mod _ exports imports decls mod_loc)\r
+ = -- These two fix-loops are to get the right\r
+ -- provenance information into a Name\r
+ fixRn (\ ~(rec_gbl_env, rec_exported_avails, _) ->\r
+\r
+ let\r
+ rec_unqual_fn :: Name -> Bool -- Is this chap in scope unqualified?\r
+ rec_unqual_fn = unQualInScope rec_gbl_env\r
+\r
+ rec_exp_fn :: Name -> ExportFlag\r
+ rec_exp_fn = mk_export_fn (availsToNameSet rec_exported_avails)\r
+ in\r
+ setModuleRn this_mod $\r
+\r
+ -- PROCESS LOCAL DECLS\r
+ -- Do these *first* so that the correct provenance gets\r
+ -- into the global name cache.\r
+ importsFromLocalDecls this_mod rec_exp_fn decls `thenRn` \ (local_gbl_env, local_mod_avails) ->\r
+\r
+ -- PROCESS IMPORT DECLS\r
+ -- Do the non {- SOURCE -} ones first, so that we get a helpful\r
+ -- warning for {- SOURCE -} ones that are unnecessary\r
+ let\r
+ (source, ordinary) = partition is_source_import all_imports\r
+ is_source_import (ImportDecl _ ImportByUserSource _ _ _ _) = True\r
+ is_source_import other = False\r
+ in\r
+ mapAndUnzipRn (importsFromImportDecl rec_unqual_fn) ordinary `thenRn` \ (imp_gbl_envs1, imp_avails_s1) ->\r
+ mapAndUnzipRn (importsFromImportDecl rec_unqual_fn) source `thenRn` \ (imp_gbl_envs2, imp_avails_s2) ->\r
+\r
+ -- COMBINE RESULTS\r
+ -- We put the local env second, so that a local provenance\r
+ -- "wins", even if a module imports itself.\r
+ let\r
+ gbl_env :: GlobalRdrEnv\r
+ imp_gbl_env = foldr plusGlobalRdrEnv emptyRdrEnv (imp_gbl_envs2 ++ imp_gbl_envs1)\r
+ gbl_env = imp_gbl_env `plusGlobalRdrEnv` local_gbl_env\r
+\r
+ all_avails :: ExportAvails\r
+ all_avails = foldr plusExportAvails local_mod_avails (imp_avails_s2 ++ imp_avails_s1)\r
+ in\r
+\r
+ -- TRY FOR EARLY EXIT\r
+ -- We can't go for an early exit before this because we have to check\r
+ -- for name clashes. Consider:\r
+ --\r
+ -- module A where module B where\r
+ -- import B h = True\r
+ -- f = h\r
+ --\r
+ -- Suppose I've compiled everything up, and then I add a\r
+ -- new definition to module B, that defines "f".\r
+ --\r
+ -- Then I must detect the name clash in A before going for an early\r
+ -- exit. The early-exit code checks what's actually needed from B\r
+ -- to compile A, and of course that doesn't include B.f. That's\r
+ -- why we wait till after the plusEnv stuff to do the early-exit.\r
+ checkEarlyExit this_mod `thenRn` \ up_to_date ->\r
+ if up_to_date then\r
+ returnRn (gbl_env, junk_exp_fn, Nothing)\r
+ else\r
+ \r
+ -- RECORD BETTER PROVENANCES IN THE CACHE\r
+ -- The names in the envirnoment have better provenances (e.g. imported on line x)\r
+ -- than the names in the name cache. We update the latter now, so that we\r
+ -- we start renaming declarations we'll get the good names\r
+ -- The isQual is because the qualified name is always in scope\r
+ updateProvenances (concat [names | (rdr_name, names) <- rdrEnvToList imp_gbl_env, \r
+ isQual rdr_name]) `thenRn_`\r
+\r
+ -- PROCESS EXPORT LISTS\r
+ exportsFromAvail this_mod exports all_avails gbl_env `thenRn` \ exported_avails ->\r
+\r
+ -- DONE\r
+ returnRn (gbl_env, exported_avails, Just all_avails)\r
+ ) `thenRn` \ (gbl_env, exported_avails, maybe_stuff) ->\r
+\r
+ case maybe_stuff of {\r
+ Nothing -> returnRn Nothing ;\r
+ Just all_avails ->\r
+\r
+ traceRn (text "updateProv" <+> fsep (map ppr (rdrEnvElts gbl_env))) `thenRn_`\r
+ \r
+ -- DEAL WITH FIXITIES\r
+ fixitiesFromLocalDecls gbl_env decls `thenRn` \ local_fixity_env ->\r
+ let\r
+ -- Export only those fixities that are for names that are\r
+ -- (a) defined in this module\r
+ -- (b) exported\r
+ exported_fixities :: [(Name,Fixity)]\r
+ exported_fixities = [(name,fixity) | FixitySig name fixity _ <- nameEnvElts local_fixity_env,\r
+ isLocallyDefined name\r
+ ]\r
+ in\r
+ traceRn (text "fixity env" <+> vcat (map ppr (nameEnvElts local_fixity_env))) `thenRn_`\r
+\r
+ --- TIDY UP \r
+ let\r
+ export_env = ExportEnv exported_avails exported_fixities\r
+ (_, global_avail_env) = all_avails\r
+ in\r
+ returnRn (Just (export_env, gbl_env, local_fixity_env, global_avail_env))\r
+ }\r
+ where\r
+ junk_exp_fn = error "RnNames:export_fn"\r
+\r
+ all_imports = prel_imports ++ imports\r
+\r
+ -- NB: opt_NoImplicitPrelude is slightly different to import Prelude ();\r
+ -- because the former doesn't even look at Prelude.hi for instance declarations,\r
+ -- whereas the latter does.\r
+ prel_imports | this_mod == pRELUDE_Name ||\r
+ explicit_prelude_import ||\r
+ opt_NoImplicitPrelude\r
+ = []\r
+\r
+ | otherwise = [ImportDecl pRELUDE_Name\r
+ ImportByUser\r
+ False {- Not qualified -}\r
+ Nothing {- No "as" -}\r
+ Nothing {- No import list -}\r
+ mod_loc]\r
+ \r
+ explicit_prelude_import\r
+ = not (null [ () | (ImportDecl mod _ _ _ _ _) <- imports, mod == pRELUDE_Name ])\r
+\end{code}\r
+ \r
+\begin{code}\r
+checkEarlyExit mod\r
+ = checkErrsRn `thenRn` \ no_errs_so_far ->\r
+ if not no_errs_so_far then\r
+ -- Found errors already, so exit now\r
+ returnRn True\r
+ else\r
+\r
+ traceRn (text "Considering whether compilation is required...") `thenRn_`\r
+ if not opt_SourceUnchanged then\r
+ -- Source code changed and no errors yet... carry on \r
+ traceRn (nest 4 (text "source file changed or recompilation check turned off")) `thenRn_` \r
+ returnRn False\r
+ else\r
+\r
+ -- Unchanged source, and no errors yet; see if usage info\r
+ -- up to date, and exit if so\r
+ checkUpToDate mod `thenRn` \ up_to_date ->\r
+ putDocRn (text "Compilation" <+> \r
+ text (if up_to_date then "IS NOT" else "IS") <+>\r
+ text "required") `thenRn_`\r
+ returnRn up_to_date\r
+\end{code}\r
+ \r
+\begin{code}\r
+importsFromImportDecl :: (Name -> Bool) -- OK to omit qualifier\r
+ -> RdrNameImportDecl\r
+ -> RnMG (GlobalRdrEnv, \r
+ ExportAvails) \r
+\r
+importsFromImportDecl is_unqual (ImportDecl imp_mod_name from qual_only as_mod import_spec iloc)\r
+ = pushSrcLocRn iloc $\r
+ getInterfaceExports imp_mod_name from `thenRn` \ (imp_mod, avails) ->\r
+\r
+ if null avails then\r
+ -- If there's an error in getInterfaceExports, (e.g. interface\r
+ -- file not found) we get lots of spurious errors from 'filterImports'\r
+ returnRn (emptyRdrEnv, mkEmptyExportAvails imp_mod_name)\r
+ else\r
+\r
+ filterImports imp_mod_name import_spec avails `thenRn` \ (filtered_avails, hides, explicits) ->\r
+\r
+ -- We 'improve' the provenance by setting\r
+ -- (a) the import-reason field, so that the Name says how it came into scope\r
+ -- including whether it's explicitly imported\r
+ -- (b) the print-unqualified field\r
+ -- But don't fiddle with wired-in things or we get in a twist\r
+ let\r
+ improve_prov name = setNameProvenance name (NonLocalDef (UserImport imp_mod iloc (is_explicit name)) \r
+ (is_unqual name))\r
+ is_explicit name = name `elemNameSet` explicits\r
+ in\r
+ qualifyImports imp_mod_name\r
+ (not qual_only) -- Maybe want unqualified names\r
+ as_mod hides\r
+ filtered_avails improve_prov `thenRn` \ (rdr_name_env, mod_avails) ->\r
+\r
+ returnRn (rdr_name_env, mod_avails)\r
+\end{code}\r
+\r
+\r
+\begin{code}\r
+importsFromLocalDecls mod_name rec_exp_fn decls\r
+ = mapRn (getLocalDeclBinders newLocalName) decls `thenRn` \ avails_s ->\r
+\r
+ let\r
+ avails = concat avails_s\r
+\r
+ all_names :: [Name] -- All the defns; no dups eliminated\r
+ all_names = [name | avail <- avails, name <- availNames avail]\r
+\r
+ dups :: [[Name]]\r
+ dups = filter non_singleton (equivClassesByUniq getUnique all_names)\r
+ where\r
+ non_singleton (x1:x2:xs) = True\r
+ non_singleton other = False\r
+ in\r
+ -- Check for duplicate definitions\r
+ mapRn_ (addErrRn . dupDeclErr) dups `thenRn_` \r
+\r
+ -- Record that locally-defined things are available\r
+ mapRn_ (recordSlurp Nothing) avails `thenRn_`\r
+\r
+ -- Build the environment\r
+ qualifyImports mod_name \r
+ True -- Want unqualified names\r
+ Nothing -- no 'as M'\r
+ [] -- Hide nothing\r
+ avails\r
+ (\n -> n)\r
+\r
+ where\r
+ newLocalName rdr_name loc = newLocalTopBinder mod (rdrNameOcc rdr_name)\r
+ rec_exp_fn loc\r
+ mod = mkThisModule mod_name\r
+\r
+getLocalDeclBinders :: (RdrName -> SrcLoc -> RnMG Name) -- New-name function\r
+ -> RdrNameHsDecl\r
+ -> RnMG Avails\r
+getLocalDeclBinders new_name (ValD binds)\r
+ = mapRn do_one (bagToList (collectTopBinders binds))\r
+ where\r
+ do_one (rdr_name, loc) = new_name rdr_name loc `thenRn` \ name ->\r
+ returnRn (Avail name)\r
+\r
+ -- foreign declarations\r
+getLocalDeclBinders new_name (ForD (ForeignDecl nm kind _ dyn _ loc))\r
+ | binds_haskell_name kind dyn\r
+ = new_name nm loc `thenRn` \ name ->\r
+ returnRn [Avail name]\r
+\r
+ | otherwise\r
+ = returnRn []\r
+\r
+getLocalDeclBinders new_name decl\r
+ = getDeclBinders new_name decl `thenRn` \ maybe_avail ->\r
+ case maybe_avail of\r
+ Nothing -> returnRn [] -- Instance decls and suchlike\r
+ Just avail -> returnRn [avail]\r
+\r
+binds_haskell_name (FoImport _) _ = True\r
+binds_haskell_name FoLabel _ = True\r
+binds_haskell_name FoExport ext_nm = isDynamic ext_nm\r
+\r
+fixitiesFromLocalDecls :: GlobalRdrEnv -> [RdrNameHsDecl] -> RnMG FixityEnv\r
+fixitiesFromLocalDecls gbl_env decls\r
+ = foldlRn getFixities emptyNameEnv decls\r
+ where\r
+ getFixities :: FixityEnv -> RdrNameHsDecl -> RnMG FixityEnv\r
+ getFixities acc (FixD fix)\r
+ = fix_decl acc fix\r
+\r
+ getFixities acc (TyClD (ClassDecl _ _ _ sigs _ _ _ _ _ _))\r
+ = foldlRn fix_decl acc [sig | FixSig sig <- sigs]\r
+ -- Get fixities from class decl sigs too.\r
+ getFixities acc other_decl\r
+ = returnRn acc\r
+\r
+ fix_decl acc sig@(FixitySig rdr_name fixity loc)\r
+ = -- Check for fixity decl for something not declared\r
+ case lookupRdrEnv gbl_env rdr_name of {\r
+ Nothing | opt_WarnUnusedBinds \r
+ -> pushSrcLocRn loc (addWarnRn (unusedFixityDecl rdr_name fixity)) `thenRn_`\r
+ returnRn acc \r
+ | otherwise -> returnRn acc ;\r
+ \r
+ Just (name:_) ->\r
+\r
+ -- Check for duplicate fixity decl\r
+ case lookupNameEnv acc name of {\r
+ Just (FixitySig _ _ loc') -> addErrRn (dupFixityDecl rdr_name loc loc') `thenRn_`\r
+ returnRn acc ;\r
+\r
+ Nothing -> returnRn (addToNameEnv acc name (FixitySig name fixity loc))\r
+ }}\r
+\end{code}\r
+\r
+%************************************************************************\r
+%* *\r
+\subsection{Filtering imports}\r
+%* *\r
+%************************************************************************\r
+\r
+@filterImports@ takes the @ExportEnv@ telling what the imported module makes\r
+available, and filters it through the import spec (if any).\r
+\r
+\begin{code}\r
+filterImports :: ModuleName -- The module being imported\r
+ -> Maybe (Bool, [RdrNameIE]) -- Import spec; True => hiding\r
+ -> [AvailInfo] -- What's available\r
+ -> RnMG ([AvailInfo], -- What's actually imported\r
+ [AvailInfo], -- What's to be hidden (the unqualified version, that is)\r
+ NameSet) -- What was imported explicitly\r
+\r
+ -- Complains if import spec mentions things that the module doesn't export\r
+ -- Warns/informs if import spec contains duplicates.\r
+filterImports mod Nothing imports\r
+ = returnRn (imports, [], emptyNameSet)\r
+\r
+filterImports mod (Just (want_hiding, import_items)) avails\r
+ = mapMaybeRn check_item import_items `thenRn` \ avails_w_explicits ->\r
+ let\r
+ (item_avails, explicits_s) = unzip avails_w_explicits\r
+ explicits = foldl addListToNameSet emptyNameSet explicits_s\r
+ in\r
+ if want_hiding \r
+ then \r
+ -- All imported; item_avails to be hidden\r
+ returnRn (avails, item_avails, emptyNameSet)\r
+ else\r
+ -- Just item_avails imported; nothing to be hidden\r
+ returnRn (item_avails, [], explicits)\r
+ where\r
+ import_fm :: FiniteMap OccName AvailInfo\r
+ import_fm = listToFM [ (nameOccName name, avail) \r
+ | avail <- avails,\r
+ name <- availNames avail]\r
+ -- Even though availNames returns data constructors too,\r
+ -- they won't make any difference because naked entities like T\r
+ -- in an import list map to TcOccs, not VarOccs.\r
+\r
+ check_item item@(IEModuleContents _)\r
+ = addErrRn (badImportItemErr mod item) `thenRn_`\r
+ returnRn Nothing\r
+\r
+ check_item item\r
+ | not (maybeToBool maybe_in_import_avails) ||\r
+ not (maybeToBool maybe_filtered_avail)\r
+ = addErrRn (badImportItemErr mod item) `thenRn_`\r
+ returnRn Nothing\r
+\r
+ | dodgy_import = addWarnRn (dodgyImportWarn mod item) `thenRn_`\r
+ returnRn (Just (filtered_avail, explicits))\r
+\r
+ | otherwise = returnRn (Just (filtered_avail, explicits))\r
+ \r
+ where\r
+ wanted_occ = rdrNameOcc (ieName item)\r
+ maybe_in_import_avails = lookupFM import_fm wanted_occ\r
+\r
+ Just avail = maybe_in_import_avails\r
+ maybe_filtered_avail = filterAvail item avail\r
+ Just filtered_avail = maybe_filtered_avail\r
+ explicits | dot_dot = [availName filtered_avail]\r
+ | otherwise = availNames filtered_avail\r
+\r
+ dot_dot = case item of \r
+ IEThingAll _ -> True\r
+ other -> False\r
+\r
+ dodgy_import = case (item, avail) of\r
+ (IEThingAll _, AvailTC _ [n]) -> True\r
+ -- This occurs when you import T(..), but\r
+ -- only export T abstractly. The single [n]\r
+ -- in the AvailTC is the type or class itself\r
+ \r
+ other -> False\r
+\end{code}\r
+\r
+\r
+\r
+%************************************************************************\r
+%* *\r
+\subsection{Qualifiying imports}\r
+%* *\r
+%************************************************************************\r
+\r
+@qualifyImports@ takes the @ExportEnv@ after filtering through the import spec\r
+of an import decl, and deals with producing an @RnEnv@ with the \r
+right qualified names. It also turns the @Names@ in the @ExportEnv@ into\r
+fully fledged @Names@.\r
+\r
+\begin{code}\r
+qualifyImports :: ModuleName -- Imported module\r
+ -> Bool -- True <=> want unqualified import\r
+ -> Maybe ModuleName -- Optional "as M" part \r
+ -> [AvailInfo] -- What's to be hidden\r
+ -> Avails -- Whats imported and how\r
+ -> (Name -> Name) -- Improves the provenance on imported things\r
+ -> RnMG (GlobalRdrEnv, ExportAvails)\r
+ -- NB: the Names in ExportAvails don't have the improve-provenance\r
+ -- function applied to them\r
+ -- We could fix that, but I don't think it matters\r
+\r
+qualifyImports this_mod unqual_imp as_mod hides\r
+ avails improve_prov\r
+ = \r
+ -- Make the name environment. We're talking about a \r
+ -- single module here, so there must be no name clashes.\r
+ -- In practice there only ever will be if it's the module\r
+ -- being compiled.\r
+ let\r
+ -- Add the things that are available\r
+ name_env1 = foldl add_avail emptyRdrEnv avails\r
+\r
+ -- Delete things that are hidden\r
+ name_env2 = foldl del_avail name_env1 hides\r
+\r
+ -- Create the export-availability info\r
+ export_avails = mkExportAvails qual_mod unqual_imp name_env2 avails\r
+ in\r
+ returnRn (name_env2, export_avails)\r
+\r
+ where\r
+ qual_mod = case as_mod of\r
+ Nothing -> this_mod\r
+ Just another_name -> another_name\r
+\r
+ add_avail :: GlobalRdrEnv -> AvailInfo -> GlobalRdrEnv\r
+ add_avail env avail = foldl add_name env (availNames avail)\r
+\r
+ add_name env name\r
+ | unqual_imp = env2\r
+ | otherwise = env1\r
+ where\r
+ env1 = addOneToGlobalRdrEnv env (mkRdrQual qual_mod occ) better_name\r
+ env2 = addOneToGlobalRdrEnv env1 (mkRdrUnqual occ) better_name\r
+ occ = nameOccName name\r
+ better_name = improve_prov name\r
+\r
+ del_avail env avail = foldl delOneFromGlobalRdrEnv env rdr_names\r
+ where\r
+ rdr_names = map (mkRdrUnqual . nameOccName) (availNames avail)\r
+\end{code}\r
+\r
+\r
+%************************************************************************\r
+%* *\r
+\subsection{Export list processing\r
+%* *\r
+%************************************************************************\r
+\r
+Processing the export list.\r
+\r
+You might think that we should record things that appear in the export list as\r
+``occurrences'' (using addOccurrenceName), but you'd be wrong. We do check (here)\r
+that they are in scope, but there is no need to slurp in their actual declaration\r
+(which is what addOccurrenceName forces). Indeed, doing so would big trouble when\r
+compiling PrelBase, because it re-exports GHC, which includes takeMVar#, whose type\r
+includes ConcBase.StateAndSynchVar#, and so on...\r
+\r
+\begin{code}\r
+type ExportAccum -- The type of the accumulating parameter of\r
+ -- the main worker function in exportsFromAvail\r
+ = ([ModuleName], -- 'module M's seen so far\r
+ ExportOccMap, -- Tracks exported occurrence names\r
+ NameEnv AvailInfo) -- The accumulated exported stuff, kept in an env\r
+ -- so we can common-up related AvailInfos\r
+\r
+type ExportOccMap = FiniteMap OccName (Name, RdrNameIE)\r
+ -- Tracks what a particular exported OccName\r
+ -- in an export list refers to, and which item\r
+ -- it came from. It's illegal to export two distinct things\r
+ -- that have the same occurrence name\r
+\r
+\r
+exportsFromAvail :: ModuleName\r
+ -> Maybe [RdrNameIE] -- Export spec\r
+ -> ExportAvails\r
+ -> GlobalRdrEnv \r
+ -> RnMG Avails\r
+ -- Complains if two distinct exports have same OccName\r
+ -- Warns about identical exports.\r
+ -- Complains about exports items not in scope\r
+exportsFromAvail this_mod Nothing export_avails global_name_env\r
+ = exportsFromAvail this_mod true_exports export_avails global_name_env\r
+ where\r
+ true_exports = Just $ if this_mod == mAIN_Name\r
+ then [IEVar main_RDR]\r
+ -- export Main.main *only* unless otherwise specified,\r
+ else [IEModuleContents this_mod]\r
+ -- but for all other modules export everything.\r
+\r
+exportsFromAvail this_mod (Just export_items) \r
+ (mod_avail_env, entity_avail_env)\r
+ global_name_env\r
+ = foldlRn exports_from_item\r
+ ([], emptyFM, emptyNameEnv) export_items `thenRn` \ (_, _, export_avail_map) ->\r
+ let\r
+ export_avails :: [AvailInfo]\r
+ export_avails = nameEnvElts export_avail_map\r
+ in\r
+ returnRn export_avails\r
+\r
+ where\r
+ exports_from_item :: ExportAccum -> RdrNameIE -> RnMG ExportAccum\r
+\r
+ exports_from_item acc@(mods, occs, avails) ie@(IEModuleContents mod)\r
+ | mod `elem` mods -- Duplicate export of M\r
+ = warnCheckRn opt_WarnDuplicateExports\r
+ (dupModuleExport mod) `thenRn_`\r
+ returnRn acc\r
+\r
+ | otherwise\r
+ = case lookupFM mod_avail_env mod of\r
+ Nothing -> failWithRn acc (modExportErr mod)\r
+ Just mod_avails -> foldlRn (check_occs ie) occs mod_avails `thenRn` \ occs' ->\r
+ let\r
+ avails' = foldl add_avail avails mod_avails\r
+ in\r
+ returnRn (mod:mods, occs', avails')\r
+\r
+ exports_from_item acc@(mods, occs, avails) ie\r
+ | not (maybeToBool maybe_in_scope) \r
+ = failWithRn acc (unknownNameErr (ieName ie))\r
+\r
+ | not (null dup_names)\r
+ = addNameClashErrRn rdr_name (name:dup_names) `thenRn_`\r
+ returnRn acc\r
+\r
+#ifdef DEBUG\r
+ -- I can't see why this should ever happen; if the thing is in scope\r
+ -- at all it ought to have some availability\r
+ | not (maybeToBool maybe_avail)\r
+ = pprTrace "exportsFromAvail: curious Nothing:" (ppr name)\r
+ returnRn acc\r
+#endif\r
+\r
+ | not enough_avail\r
+ = failWithRn acc (exportItemErr ie)\r
+\r
+ | otherwise -- Phew! It's OK! Now to check the occurrence stuff!\r
+ = check_occs ie occs export_avail `thenRn` \ occs' ->\r
+ returnRn (mods, occs', add_avail avails export_avail)\r
+\r
+ where\r
+ rdr_name = ieName ie\r
+ maybe_in_scope = lookupFM global_name_env rdr_name\r
+ Just (name:dup_names) = maybe_in_scope\r
+ maybe_avail = lookupUFM entity_avail_env name\r
+ Just avail = maybe_avail\r
+ maybe_export_avail = filterAvail ie avail\r
+ enough_avail = maybeToBool maybe_export_avail\r
+ Just export_avail = maybe_export_avail\r
+\r
+add_avail avails avail = addToNameEnv_C plusAvail avails (availName avail) avail\r
+\r
+check_occs :: RdrNameIE -> ExportOccMap -> AvailInfo -> RnMG ExportOccMap\r
+check_occs ie occs avail \r
+ = foldlRn check occs (availNames avail)\r
+ where\r
+ check occs name\r
+ = case lookupFM occs name_occ of\r
+ Nothing -> returnRn (addToFM occs name_occ (name, ie))\r
+ Just (name', ie') \r
+ | name == name' -> -- Duplicate export\r
+ warnCheckRn opt_WarnDuplicateExports\r
+ (dupExportWarn name_occ ie ie') `thenRn_`\r
+ returnRn occs\r
+\r
+ | otherwise -> -- Same occ name but different names: an error\r
+ failWithRn occs (exportClashErr name_occ ie ie')\r
+ where\r
+ name_occ = nameOccName name\r
+ \r
+mk_export_fn :: NameSet -> (Name -> ExportFlag)\r
+mk_export_fn exported_names\r
+ = \name -> if name `elemNameSet` exported_names\r
+ then Exported\r
+ else NotExported\r
+\end{code}\r
+\r
+%************************************************************************\r
+%* *\r
+\subsection{Errors}\r
+%* *\r
+%************************************************************************\r
+\r
+\begin{code}\r
+badImportItemErr mod ie\r
+ = sep [ptext SLIT("Module"), quotes (pprModuleName mod), \r
+ ptext SLIT("does not export"), quotes (ppr ie)]\r
+\r
+dodgyImportWarn mod (IEThingAll tc)\r
+ = sep [ptext SLIT("Module") <+> quotes (pprModuleName mod) <+> ptext SLIT("exports") <+> quotes (ppr tc), \r
+ ptext SLIT("with no constructors/class operations;"),\r
+ ptext SLIT("yet it is imported with a (..)")]\r
+\r
+modExportErr mod\r
+ = hsep [ ptext SLIT("Unknown module in export list: module"), quotes (pprModuleName mod)]\r
+\r
+exportItemErr export_item\r
+ = sep [ ptext SLIT("Bad export item"), quotes (ppr export_item)]\r
+\r
+exportClashErr occ_name ie1 ie2\r
+ = hsep [ptext SLIT("The export items"), quotes (ppr ie1), ptext SLIT("and"), quotes (ppr ie2),\r
+ ptext SLIT("create conflicting exports for"), quotes (ppr occ_name)]\r
+\r
+dupDeclErr (n:ns)\r
+ = vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr n),\r
+ nest 4 (vcat (map pp sorted_ns))]\r
+ where\r
+ sorted_ns = sortLt occ'ed_before (n:ns)\r
+\r
+ occ'ed_before a b = LT == compare (getSrcLoc a) (getSrcLoc b)\r
+\r
+ pp n = pprProvenance (getNameProvenance n)\r
+\r
+dupExportWarn occ_name ie1 ie2\r
+ = hsep [quotes (ppr occ_name), \r
+ ptext SLIT("is exported by"), quotes (ppr ie1),\r
+ ptext SLIT("and"), quotes (ppr ie2)]\r
+\r
+dupModuleExport mod\r
+ = hsep [ptext SLIT("Duplicate"),\r
+ quotes (ptext SLIT("Module") <+> pprModuleName mod), \r
+ ptext SLIT("in export list")]\r
+\r
+unusedFixityDecl rdr_name fixity\r
+ = hsep [ptext SLIT("Unused fixity declaration for"), quotes (ppr rdr_name)]\r
+\r
+dupFixityDecl rdr_name loc1 loc2\r
+ = vcat [ptext SLIT("Multiple fixity declarations for") <+> quotes (ppr rdr_name),\r
+ ptext SLIT("at ") <+> ppr loc1,\r
+ ptext SLIT("and") <+> ppr loc2]\r
+\r
+\end{code}\r