\begin{code}
module RnNames (
- getGlobalNames
+ rnImports, importsFromLocalDecls,
+ reportUnusedNames, reportDeprecations,
+ mkModDeps, exportsToAvails, exportsFromAvail
) where
#include "HsVersions.h"
import CmdLineOpts ( DynFlag(..) )
-
-import HsSyn ( HsModule(..), HsDecl(..), IE(..), ieName, ImportDecl(..),
- ForeignDecl(..), ForKind(..), isDynamicExtName,
- collectTopBinders
- )
-import RdrHsSyn ( RdrNameIE, RdrNameImportDecl,
- RdrNameHsModule, RdrNameHsDecl
+import HsSyn ( IE(..), ieName, ImportDecl(..), LImportDecl,
+ ForeignDecl(..), HsGroup(..), HsBindGroup(..),
+ Sig(..), collectGroupBinders, tyClDeclNames
)
-import RnIfaces ( getInterfaceExports, recordLocalSlurps )
-import RnHiFiles ( getTyClDeclBinders )
import RnEnv
-import RnMonad
+import IfaceEnv ( lookupOrig, newGlobalBinder )
+import LoadIface ( loadSrcInterface )
+import TcRnMonad
import FiniteMap
-import PrelNames ( pRELUDE_Name, mAIN_Name, main_RDR_Unqual, isUnboundName )
-import UniqFM ( lookupUFM )
-import Bag ( bagToList )
-import Module ( ModuleName, moduleName, WhereFrom(..) )
+import PrelNames ( pRELUDE, isUnboundName, main_RDR_Unqual )
+import Module ( Module, moduleUserString,
+ unitModuleEnv, unitModuleEnv,
+ lookupModuleEnv, moduleEnvElts, foldModuleEnv )
+import Name ( Name, nameSrcLoc, nameOccName, nameModule, isWiredInName,
+ nameParent, nameParent_maybe, isExternalName,
+ isBuiltInSyntax )
import NameSet
-import Name ( Name, nameSrcLoc,
- setLocalNameSort, nameOccName, nameEnvElts )
-import HscTypes ( Provenance(..), ImportReason(..), GlobalRdrEnv,
- GenAvailInfo(..), AvailInfo, Avails, AvailEnv )
-import RdrName ( RdrName, rdrNameOcc, setRdrNameOcc, mkRdrQual, mkRdrUnqual )
-import OccName ( setOccNameSpace, dataName )
-import NameSet ( elemNameSet, emptyNameSet )
+import NameEnv
+import OccName ( srcDataName, isTcOcc, occNameFlavour, OccEnv,
+ mkOccEnv, lookupOccEnv, emptyOccEnv, extendOccEnv )
+import HscTypes ( GenAvailInfo(..), AvailInfo, GhciMode(..),
+ IfaceExport, HomePackageTable, PackageIfaceTable,
+ availNames, unQualInScope,
+ Deprecs(..), ModIface(..), Dependencies(..),
+ lookupIface, ExternalPackageState(..)
+ )
+import Packages ( PackageIdH(..) )
+import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace,
+ GlobalRdrEnv, mkGlobalRdrEnv, GlobalRdrElt(..),
+ emptyGlobalRdrEnv, plusGlobalRdrEnv, globalRdrEnvElts,
+ unQualOK, lookupGRE_Name,
+ Provenance(..), ImportSpec(..),
+ isLocalGRE, pprNameProvenance )
import Outputable
-import Maybes ( maybeToBool, catMaybes, mapMaybe )
-import UniqFM ( emptyUFM, listToUFM )
+import Maybes ( isNothing, catMaybes, mapCatMaybes, seqMaybe, orElse )
+import SrcLoc ( noSrcLoc, Located(..), mkGeneralSrcSpan,
+ unLoc, noLoc, srcLocSpan, combineSrcSpans, SrcSpan )
+import BasicTypes ( DeprecTxt )
import ListSetOps ( removeDups )
-import Util ( sortLt )
+import Util ( sortLe, notNull, isSingleton )
import List ( partition )
+import IO ( openFile, IOMode(..) )
\end{code}
%************************************************************************
%* *
-\subsection{Get global names}
+ rnImports
%* *
%************************************************************************
\begin{code}
-getGlobalNames :: Module -> RdrNameHsModule
- -> RnMG (GlobalRdrEnv, -- Maps all in-scope things
- GlobalRdrEnv, -- Maps just *local* things
- Avails, -- The exported stuff
- AvailEnv) -- Maps a name to its parent AvailInfo
- -- Just for in-scope things only
-
-getGlobalNames this_mod (HsModule _ _ exports imports decls _ mod_loc)
- = -- These two fix-loops are to get the right
- -- provenance information into a Name
- fixRn ( \ ~(rec_gbl_env, _, rec_export_avails, _) ->
-
- let
- rec_exp_fn :: Name -> Bool
- rec_exp_fn = mk_export_fn (availsToNameSet rec_export_avails)
- in
-
- -- PROCESS LOCAL DECLS
- -- Do these *first* so that the correct provenance gets
- -- into the global name cache.
- importsFromLocalDecls this_mod rec_exp_fn decls `thenRn` \ (local_gbl_env, local_mod_avails) ->
-
- -- PROCESS IMPORT DECLS
+rnImports :: [LImportDecl RdrName]
+ -> RnM (GlobalRdrEnv, ImportAvails)
+
+rnImports imports
+ = do { -- PROCESS IMPORT DECLS
-- Do the non {- SOURCE -} ones first, so that we get a helpful
-- warning for {- SOURCE -} ones that are unnecessary
- doptRn Opt_NoImplicitPrelude `thenRn` \ opt_no_prelude ->
- let
- all_imports = mk_prel_imports opt_no_prelude ++ imports
- (source, ordinary) = partition is_source_import all_imports
- is_source_import (ImportDecl _ ImportByUserSource _ _ _ _) = True
- is_source_import other = False
-
- get_imports = importsFromImportDecl this_mod_name
- in
- mapAndUnzipRn get_imports ordinary `thenRn` \ (imp_gbl_envs1, imp_avails_s1) ->
- mapAndUnzipRn get_imports source `thenRn` \ (imp_gbl_envs2, imp_avails_s2) ->
+ this_mod <- getModule
+ ; implicit_prelude <- doptM Opt_ImplicitPrelude
+ ; let
+ all_imports = mk_prel_imports this_mod implicit_prelude ++ imports
+ (source, ordinary) = partition is_source_import all_imports
+ is_source_import (L _ (ImportDecl _ is_boot _ _ _)) = is_boot
+
+ get_imports = importsFromImportDecl this_mod
+
+ ; stuff1 <- mappM get_imports ordinary
+ ; stuff2 <- mappM get_imports source
-- COMBINE RESULTS
- -- We put the local env second, so that a local provenance
- -- "wins", even if a module imports itself.
- let
+ ; let
+ (imp_gbl_envs, imp_avails) = unzip (stuff1 ++ stuff2)
gbl_env :: GlobalRdrEnv
- imp_gbl_env = foldr plusGlobalRdrEnv emptyRdrEnv (imp_gbl_envs2 ++ imp_gbl_envs1)
- gbl_env = imp_gbl_env `plusGlobalRdrEnv` local_gbl_env
-
- all_avails :: ExportAvails
- all_avails = foldr plusExportAvails local_mod_avails (imp_avails_s2 ++ imp_avails_s1)
-
- (_, global_avail_env) = all_avails
- in
-
- -- PROCESS EXPORT LIST (but not if we've had errors already)
- checkErrsRn `thenRn` \ no_errs_so_far ->
- (if no_errs_so_far then
- exportsFromAvail this_mod_name exports all_avails gbl_env
- else
- returnRn []
- ) `thenRn` \ export_avails ->
-
+ gbl_env = foldr plusGlobalRdrEnv emptyGlobalRdrEnv imp_gbl_envs
+
+ all_avails :: ImportAvails
+ all_avails = foldr plusImportAvails emptyImportAvails imp_avails
+
-- ALL DONE
- returnRn (gbl_env, local_gbl_env, export_avails, global_avail_env)
- )
+ ; return (gbl_env, all_avails) }
where
- this_mod_name = moduleName this_mod
-
-- NB: opt_NoImplicitPrelude is slightly different to import Prelude ();
- -- because the former doesn't even look at Prelude.hi for instance declarations,
- -- whereas the latter does.
- mk_prel_imports no_prelude
- | this_mod_name == pRELUDE_Name ||
- explicit_prelude_import ||
- no_prelude
+ -- because the former doesn't even look at Prelude.hi for instance
+ -- declarations, whereas the latter does.
+ mk_prel_imports this_mod implicit_prelude
+ | this_mod == pRELUDE
+ || explicit_prelude_import
+ || not implicit_prelude
= []
- | otherwise = [ImportDecl pRELUDE_Name
- ImportByUser
- False {- Not qualified -}
- Nothing {- No "as" -}
- Nothing {- No import list -}
- mod_loc]
-
+ | otherwise = [preludeImportDecl]
+
explicit_prelude_import
- = not (null [ () | (ImportDecl mod _ _ _ _ _) <- imports, mod == pRELUDE_Name ])
+ = notNull [ () | L _ (ImportDecl mod _ _ _ _) <- imports,
+ unLoc mod == pRELUDE ]
+
+preludeImportDecl
+ = L loc $
+ ImportDecl (L loc pRELUDE)
+ False {- Not a boot interface -}
+ False {- Not qualified -}
+ Nothing {- No "as" -}
+ Nothing {- No import list -}
+ where
+ loc = mkGeneralSrcSpan FSLIT("Implicit import declaration")
\end{code}
\begin{code}
-importsFromImportDecl :: ModuleName
- -> RdrNameImportDecl
- -> RnMG (GlobalRdrEnv,
- ExportAvails)
+importsFromImportDecl :: Module
+ -> LImportDecl RdrName
+ -> RnM (GlobalRdrEnv, ImportAvails)
-importsFromImportDecl this_mod_name (ImportDecl imp_mod_name from qual_only as_mod import_spec iloc)
- = pushSrcLocRn iloc $
- getInterfaceExports imp_mod_name from `thenRn` \ (imp_mod, avails_by_module) ->
+importsFromImportDecl this_mod
+ (L loc (ImportDecl loc_imp_mod_name want_boot qual_only as_mod imp_details))
+ =
+ setSrcSpan loc $
- if null avails_by_module then
- -- If there's an error in getInterfaceExports, (e.g. interface
+ -- If there's an error in loadInterface, (e.g. interface
-- file not found) we get lots of spurious errors from 'filterImports'
- returnRn (emptyRdrEnv, mkEmptyExportAvails imp_mod_name)
- else
+ let
+ imp_mod_name = unLoc loc_imp_mod_name
+ doc = ppr imp_mod_name <+> ptext SLIT("is directly imported")
+ in
+ loadSrcInterface doc imp_mod_name want_boot `thenM` \ iface ->
+
+ -- Compiler sanity check: if the import didn't say
+ -- {-# SOURCE #-} we should not get a hi-boot file
+ WARN( not want_boot && mi_boot iface, ppr imp_mod_name )
+
+ -- Issue a user warning for a redundant {- SOURCE -} import
+ -- NB that we arrange to read all the ordinary imports before
+ -- any of the {- SOURCE -} imports
+ warnIf (want_boot && not (mi_boot iface))
+ (warnRedundantSourceImport imp_mod_name) `thenM_`
let
- avails :: Avails
- avails = [ avail | (mod_name, avails) <- avails_by_module,
- mod_name /= this_mod_name,
- avail <- avails ]
+ imp_mod = mi_module iface
+ deprecs = mi_deprecs iface
+ is_orph = mi_orphan iface
+ deps = mi_deps iface
+
+ filtered_exports = filter not_this_mod (mi_exports iface)
+ not_this_mod (mod,_) = mod /= this_mod
-- 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
--
-- then you'll get a 'B does not export AType' message. Oh well.
+ qual_mod_name = case as_mod of
+ Nothing -> imp_mod_name
+ Just another_name -> another_name
+ imp_spec = ImportSpec { is_mod = imp_mod_name, is_qual = qual_only,
+ is_loc = loc, is_as = qual_mod_name }
in
- filterImports imp_mod_name from import_spec avails `thenRn` \ (filtered_avails, hides, explicits) ->
+ -- Get the total imports, and filter them according to the import list
+ exportsToAvails filtered_exports `thenM` \ total_avails ->
+ filterImports iface imp_spec
+ imp_details total_avails `thenM` \ (avail_env, gbl_env) ->
+
+ getDOpts `thenM` \ dflags ->
let
- mk_provenance name = NonLocalDef (UserImport imp_mod iloc (name `elemNameSet` explicits))
- in
+ -- Compute new transitive dependencies
+
+ orphans | is_orph = ASSERT( not (imp_mod_name `elem` dep_orphs deps) )
+ imp_mod_name : dep_orphs deps
+ | otherwise = dep_orphs deps
+
+ (dependent_mods, dependent_pkgs)
+ = case mi_package iface of
+ HomePackage ->
+ -- Imported module is from the home package
+ -- Take its dependent modules and add imp_mod itself
+ -- Take its dependent packages unchanged
+ --
+ -- NB: (dep_mods deps) might include a hi-boot file
+ -- for the module being compiled, CM. Do *not* filter
+ -- this out (as we used to), because when we've
+ -- finished dealing with the direct imports we want to
+ -- know if any of them depended on CM.hi-boot, in
+ -- which case we should do the hi-boot consistency
+ -- check. See LoadIface.loadHiBootInterface
+ ((imp_mod_name, want_boot) : dep_mods deps, dep_pkgs deps)
+
+ ExtPackage pkg ->
+ -- Imported module is from another package
+ -- Dump the dependent modules
+ -- Add the package imp_mod comes from to the dependent packages
+ ASSERT2( not (pkg `elem` dep_pkgs deps), ppr pkg <+> ppr (dep_pkgs deps) )
+ ([], pkg : dep_pkgs deps)
+
+ import_all = case imp_details of
+ Just (is_hiding, ls) -- Imports are spec'd explicitly
+ | not is_hiding -> Just (not (null ls))
+ _ -> Nothing -- Everything is imported,
+ -- (or almost everything [hiding])
+
+ -- unqual_avails is the Avails that are visible in *unqualified* form
+ -- We need to know this so we know what to export when we see
+ -- module M ( module P ) where ...
+ -- Then we must export whatever came from P unqualified.
+ imports = ImportAvails {
+ imp_env = unitModuleEnv qual_mod_name avail_env,
+ imp_mods = unitModuleEnv imp_mod (imp_mod, import_all, loc),
+ imp_orphs = orphans,
+ imp_dep_mods = mkModDeps dependent_mods,
+ imp_dep_pkgs = dependent_pkgs }
- qualifyImports imp_mod_name
- (not qual_only) -- Maybe want unqualified names
- as_mod hides
- mk_provenance
- filtered_avails
+ in
+ -- Complain if we import a deprecated module
+ ifOptM Opt_WarnDeprecations (
+ case deprecs of
+ DeprecAll txt -> addWarn (moduleDeprec imp_mod_name txt)
+ other -> returnM ()
+ ) `thenM_`
+
+ returnM (gbl_env, imports)
+
+exportsToAvails :: [IfaceExport] -> TcRnIf gbl lcl NameSet
+exportsToAvails exports
+ = foldlM do_one emptyNameSet exports
+ where
+ do_one acc (mod, exports) = foldlM (do_avail mod) acc exports
+ do_avail mod acc (Avail n) = do { n' <- lookupOrig mod n;
+ ; return (addOneToNameSet acc n') }
+ do_avail mod acc (AvailTC p_occ occs)
+ = do { p_name <- lookupOrig mod p_occ
+ ; ns <- mappM (lookup_sub p_name) occs
+ ; return (addListToNameSet acc ns) }
+ -- Remember that 'occs' is all the exported things, including
+ -- the parent. It's possible to export just class ops without
+ -- the class, via C( op ). If the class was exported too we'd
+ -- have C( C, op )
+ where
+ lookup_sub parent occ
+ = newGlobalBinder mod occ mb_parent noSrcLoc
+ where
+ mb_parent | occ == p_occ = Nothing
+ | otherwise = Just parent
+
+ -- The use of newGlobalBinder here (rather than lookupOrig)
+ -- ensures that the subordinate names record their parent;
+ -- and that in turn ensures that the GlobalRdrEnv
+ -- has the correct parent for all the names in its range.
+ -- For imported things, we may only suck in the interface later, if ever.
+ -- Reason for all this:
+ -- Suppose module M exports type A.T, and constructor A.MkT
+ -- Then, we know that A.MkT is a subordinate name of A.T,
+ -- even though we aren't at the binding site of A.T
+ -- And it's important, because we may simply re-export A.T
+ -- without ever sucking in the declaration itself.
+
+warnRedundantSourceImport mod_name
+ = ptext SLIT("Unnecessary {- SOURCE -} in the import of module")
+ <+> quotes (ppr mod_name)
\end{code}
-\begin{code}
-importsFromLocalDecls this_mod rec_exp_fn decls
- = mapRn (getLocalDeclBinders this_mod rec_exp_fn) decls `thenRn` \ avails_s ->
+%************************************************************************
+%* *
+ importsFromLocalDecls
+%* *
+%************************************************************************
- let
- avails = concat avails_s
+From the top-level declarations of this module produce
+ * the lexical environment
+ * the ImportAvails
+created by its bindings.
+
+Complain about duplicate bindings
+\begin{code}
+importsFromLocalDecls :: HsGroup RdrName
+ -> RnM (GlobalRdrEnv, ImportAvails)
+importsFromLocalDecls group
+ = getModule `thenM` \ this_mod ->
+ getLocalDeclBinders this_mod group `thenM` \ avails ->
+ -- The avails that are returned don't include the "system" names
+ let
all_names :: [Name] -- All the defns; no dups eliminated
all_names = [name | avail <- avails, name <- availNames avail]
(_, dups) = removeDups compare all_names
in
-- Check for duplicate definitions
- mapRn_ (addErrRn . dupDeclErr) dups `thenRn_`
-
- -- Record that locally-defined things are available
- recordLocalSlurps avails `thenRn_`
-
- -- Build the environment
- qualifyImports (moduleName this_mod)
- True -- Want unqualified names
- Nothing -- no 'as M'
- [] -- Hide nothing
- (\n -> LocalDef) -- Provenance is local
- avails
-
----------------------------
-getLocalDeclBinders :: Module
- -> (Name -> Bool) -- Whether exported
- -> RdrNameHsDecl -> RnMG Avails
-getLocalDeclBinders mod rec_exp_fn (TyClD tycl_decl)
+ -- The complaint will come out as "Multiple declarations of Foo.f" because
+ -- since 'f' is in the env twice, the unQualInScope used by the error-msg
+ -- printer returns False. It seems awkward to fix, unfortunately.
+ mappM_ addDupDeclErr dups `thenM_`
+
+ doptM Opt_ImplicitPrelude `thenM` \ implicit_prelude ->
+ let
+ prov = LocalDef this_mod
+ gbl_env = mkGlobalRdrEnv gres
+ gres = [ GRE { gre_name = name, gre_prov = prov}
+ | name <- all_names]
+
+ -- Optimisation: filter out names for built-in syntax
+ -- They just clutter up the environment (esp tuples), and the parser
+ -- will generate Exact RdrNames for them, so the cluttered
+ -- envt is no use. To avoid doing this filter all the time,
+ -- we use -fno-implicit-prelude as a clue that the filter is
+ -- worth while. Really, it's only useful for GHC.Base and GHC.Tuple.
+ --
+ -- It's worth doing because it makes the environment smaller for
+ -- every module that imports the Prelude
+ --
+ -- Note: don't filter the gbl_env (hence all_names, not filered_all_names
+ -- in defn of gres above). Stupid reason: when parsing
+ -- data type decls, the constructors start as Exact tycon-names,
+ -- and then get turned into data con names by zapping the name space;
+ -- but that stops them being Exact, so they get looked up.
+ -- Ditto in fixity decls; e.g. infix 5 :
+ -- Sigh. It doesn't matter because it only affects the Data.Tuple really.
+ -- The important thing is to trim down the exports.
+ filtered_names
+ | implicit_prelude = all_names
+ | otherwise = filter (not . isBuiltInSyntax) all_names
+
+ imports = emptyImportAvails {
+ imp_env = unitModuleEnv this_mod $
+ mkNameSet filtered_names
+ }
+ in
+ returnM (gbl_env, imports)
+\end{code}
+
+
+%*********************************************************
+%* *
+\subsection{Getting binders out of a declaration}
+%* *
+%*********************************************************
+
+@getLocalDeclBinders@ returns the names for an @HsDecl@. It's
+used for source code.
+
+ *** See "THE NAMING STORY" in HsDecls ****
+
+\begin{code}
+getLocalDeclBinders :: Module -> HsGroup RdrName -> RnM [AvailInfo]
+getLocalDeclBinders mod (HsGroup {hs_valds = val_decls,
+ hs_tyclds = tycl_decls,
+ hs_fords = foreign_decls })
= -- For type and class decls, we generate Global names, with
-- no export indicator. They need to be global because they get
-- permanently bound into the TyCons and Classes. They don't need
-- an export indicator because they are all implicitly exported.
- getTyClDeclBinders mod tycl_decl `thenRn` \ avail ->
- returnRn [avail]
-
-getLocalDeclBinders mod rec_exp_fn (ValD binds)
- = mapRn (newLocalBinder mod rec_exp_fn)
- (bagToList (collectTopBinders binds))
-getLocalDeclBinders mod rec_exp_fn (ForD (ForeignDecl nm kind _ ext_nm _ loc))
- | binds_haskell_name kind
- = newLocalBinder mod rec_exp_fn (nm, loc) `thenRn` \ avail ->
- returnRn [avail]
+ mappM new_tc tycl_decls `thenM` \ tc_avails ->
+
+ -- In a hs-boot file, the value binders come from the
+ -- *signatures*, and there should be no foreign binders
+ tcIsHsBoot `thenM` \ is_hs_boot ->
+ let val_bndrs | is_hs_boot = sig_hs_bndrs
+ | otherwise = for_hs_bndrs ++ val_hs_bndrs
+ in
+ mappM new_simple val_bndrs `thenM` \ names ->
- | otherwise -- a foreign export
- = returnRn []
+ returnM (tc_avails ++ map Avail names)
where
- binds_haskell_name (FoImport _) = True
- binds_haskell_name FoLabel = True
- binds_haskell_name FoExport = isDynamicExtName ext_nm
-
-getLocalDeclBinders mod rec_exp_fn (FixD _) = returnRn []
-getLocalDeclBinders mod rec_exp_fn (DeprecD _) = returnRn []
-getLocalDeclBinders mod rec_exp_fn (DefD _) = returnRn []
-getLocalDeclBinders mod rec_exp_fn (InstD _) = returnRn []
-getLocalDeclBinders mod rec_exp_fn (RuleD _) = returnRn []
-
----------------------------
-newLocalBinder mod rec_exp_fn (rdr_name, loc)
- = -- Generate a local name, and with a suitable export indicator
- newTopBinder mod rdr_name loc `thenRn` \ name ->
- returnRn (Avail (setLocalNameSort name (rec_exp_fn name)))
+ new_simple rdr_name = newTopSrcBinder mod Nothing rdr_name
+
+ sig_hs_bndrs = [nm | HsBindGroup _ lsigs _ <- val_decls,
+ L _ (Sig nm _) <- lsigs]
+ val_hs_bndrs = collectGroupBinders val_decls
+ for_hs_bndrs = [nm | L _ (ForeignImport nm _ _ _) <- foreign_decls]
+
+ new_tc tc_decl
+ = newTopSrcBinder mod Nothing main_rdr `thenM` \ main_name ->
+ mappM (newTopSrcBinder mod (Just main_name)) sub_rdrs `thenM` \ sub_names ->
+ returnM (AvailTC main_name (main_name : sub_names))
+ where
+ (main_rdr : sub_rdrs) = tyClDeclNames (unLoc tc_decl)
\end{code}
available, and filters it through the import spec (if any).
\begin{code}
-filterImports :: ModuleName -- The module being imported
- -> WhereFrom -- Tells whether it's a {-# SOURCE #-} import
- -> Maybe (Bool, [RdrNameIE]) -- Import spec; True => hiding
- -> [AvailInfo] -- What's available
- -> RnMG ([AvailInfo], -- What's actually imported
- [AvailInfo], -- What's to be hidden
- -- (the unqualified version, that is)
- -- (We need to return both the above sets, because
- -- the qualified version is never hidden; so we can't
- -- implement hiding by reducing what's imported.)
- NameSet) -- What was imported explicitly
+filterImports :: ModIface
+ -> ImportSpec -- The span for the entire import decl
+ -> Maybe (Bool, [Located (IE RdrName)]) -- Import spec; True => hiding
+ -> NameSet -- What's available
+ -> RnM (NameSet, -- What's imported (qualified or unqualified)
+ GlobalRdrEnv) -- Same again, but in GRE form
-- Complains if import spec mentions things that the module doesn't export
-- Warns/informs if import spec contains duplicates.
-filterImports mod from Nothing imports
- = returnRn (imports, [], emptyNameSet)
+
+mkGenericRdrEnv imp_spec names
+ = mkGlobalRdrEnv [ GRE { gre_name = name, gre_prov = Imported [imp_spec] False }
+ | name <- nameSetToList names ]
+
+filterImports iface imp_spec Nothing all_names
+ = returnM (all_names, mkGenericRdrEnv imp_spec all_names)
-filterImports mod from (Just (want_hiding, import_items)) total_avails
- = flatMapRn get_item import_items `thenRn` \ avails_w_explicits ->
+filterImports iface imp_spec (Just (want_hiding, import_items)) all_names
+ = mappM (addLocM get_item) import_items `thenM` \ gres_s ->
let
- (item_avails, explicits_s) = unzip avails_w_explicits
- explicits = foldl addListToNameSet emptyNameSet explicits_s
+ gres = concat gres_s
+ specified_names = mkNameSet (map gre_name gres)
in
- if want_hiding
- then
- -- All imported; item_avails to be hidden
- returnRn (total_avails, item_avails, emptyNameSet)
+ if not want_hiding then
+ return (specified_names, mkGlobalRdrEnv gres)
else
- -- Just item_avails imported; nothing to be hidden
- returnRn (item_avails, [], explicits)
+ let
+ keep n = not (n `elemNameSet` specified_names)
+ pruned_avails = filterNameSet keep all_names
+ in
+ return (pruned_avails, mkGenericRdrEnv imp_spec pruned_avails)
+
where
- import_fm :: FiniteMap OccName AvailInfo
- import_fm = listToFM [ (nameOccName name, avail)
- | avail <- total_avails,
- name <- availNames avail]
- -- Even though availNames returns data constructors too,
+ occ_env :: OccEnv Name -- Maps OccName to corresponding Name
+ occ_env = mkOccEnv [(nameOccName n, n) | n <- nameSetToList all_names]
+ -- This env will have entries for data constructors too,
-- they won't make any difference because naked entities like T
-- in an import list map to TcOccs, not VarOccs.
- bale_out item = addErrRn (badImportItemErr mod from item) `thenRn_`
- returnRn []
+ sub_env :: NameEnv [Name]
+ sub_env = mkSubNameEnv all_names
- get_item item@(IEModuleContents _) = bale_out item
+ bale_out item = addErr (badImportItemErr iface imp_spec item) `thenM_`
+ returnM []
- get_item item@(IEThingAll _)
+ succeed_with :: Bool -> [Name] -> RnM [GlobalRdrElt]
+ succeed_with all_explicit names
+ = do { loc <- getSrcSpanM
+ ; returnM (map (mk_gre loc) names) }
+ where
+ mk_gre loc name = GRE { gre_name = name,
+ gre_prov = Imported [this_imp_spec loc] (explicit name) }
+ this_imp_spec loc = imp_spec { is_loc = loc }
+ explicit name = all_explicit || isNothing (nameParent_maybe name)
+
+ get_item :: IE RdrName -> RnM [GlobalRdrElt]
+ -- Empty result for a bad item.
+ -- Singleton result is typical case.
+ -- Can have two when we are hiding, and mention C which might be
+ -- both a class and a data constructor.
+ get_item item@(IEModuleContents _)
+ = bale_out item
+
+ get_item item@(IEThingAll tc)
= case check_item item of
- Nothing -> bale_out item
- Just avail@(AvailTC _ [n]) -> -- This occurs when you import T(..), but
- -- only export T abstractly. The single [n]
- -- in the AvailTC is the type or class itself
- addWarnRn (dodgyImportWarn mod item) `thenRn_`
- returnRn [(avail, [availName avail])]
- Just avail -> returnRn [(avail, [availName avail])]
+ [] -> bale_out item
+
+ [n] -> -- This occurs when you import T(..), but
+ -- only export T abstractly. The single [n]
+ -- in the AvailTC is the type or class itself
+ ifOptM Opt_WarnDodgyImports (addWarn (dodgyImportWarn tc)) `thenM_`
+ succeed_with False [n]
+
+ names -> succeed_with False names
get_item item@(IEThingAbs n)
| want_hiding -- hiding( C )
- -- Here the 'C' can be a data constructor *or* a type/class
- = case catMaybes [check_item item, check_item (IEThingAbs data_n)] of
- [] -> bale_out item
- avails -> returnRn [(a, []) | a <- avails]
- -- The 'explicits' list is irrelevant when hiding
+ -- Here the 'C' can be a data constructor
+ -- *or* a type/class, or even both
+ = case concat [check_item item, check_item (IEVar data_n)] of
+ [] -> bale_out item
+ names -> succeed_with True names
where
- data_n = setRdrNameOcc n (setOccNameSpace (rdrNameOcc n) dataName)
+ data_n = setRdrNameSpace n srcDataName
get_item item
= case check_item item of
- Nothing -> bale_out item
- Just avail -> returnRn [(avail, availNames avail)]
-
- check_item item
- | not (maybeToBool maybe_in_import_avails) ||
- not (maybeToBool maybe_filtered_avail)
- = Nothing
-
- | otherwise
- = Just filtered_avail
-
- where
- wanted_occ = rdrNameOcc (ieName item)
- maybe_in_import_avails = lookupFM import_fm wanted_occ
-
- Just avail = maybe_in_import_avails
- maybe_filtered_avail = filterAvail item avail
- Just filtered_avail = maybe_filtered_avail
-\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 qualified names. It also turns the @Names@ in the @ExportEnv@ into
-fully fledged @Names@.
-
-\begin{code}
-qualifyImports :: ModuleName -- Imported module
- -> Bool -- True <=> want unqualified import
- -> Maybe ModuleName -- Optional "as M" part
- -> [AvailInfo] -- What's to be hidden
- -> (Name -> Provenance)
- -> Avails -- Whats imported and how
- -> RnMG (GlobalRdrEnv, ExportAvails)
-
-qualifyImports this_mod unqual_imp as_mod hides mk_provenance avails
- =
- -- Make the name environment. We're talking about a
- -- single module here, so there must be no name clashes.
- -- In practice there only ever will be if it's the module
- -- being compiled.
- let
- -- Add the things that are available
- name_env1 = foldl add_avail emptyRdrEnv avails
-
- -- Delete things that are hidden
- name_env2 = foldl del_avail name_env1 hides
-
- -- Create the export-availability info
- export_avails = mkExportAvails qual_mod unqual_imp name_env2 avails
- in
- returnRn (name_env2, export_avails)
-
- where
- qual_mod = case as_mod of
- Nothing -> this_mod
- Just another_name -> another_name
-
- add_avail :: GlobalRdrEnv -> AvailInfo -> GlobalRdrEnv
- add_avail env avail = foldl add_name env (availNames avail)
-
- add_name env name
- | unqual_imp = env2
- | otherwise = env1
- where
- env1 = addOneToGlobalRdrEnv env (mkRdrQual qual_mod occ) (name,prov)
- env2 = addOneToGlobalRdrEnv env1 (mkRdrUnqual occ) (name,prov)
- occ = nameOccName name
- prov = mk_provenance name
-
- del_avail env avail = foldl delOneFromGlobalRdrEnv env rdr_names
- where
- rdr_names = map (mkRdrUnqual . nameOccName) (availNames avail)
-
-
-mkEmptyExportAvails :: ModuleName -> ExportAvails
-mkEmptyExportAvails mod_name = (unitFM mod_name [], emptyUFM)
-
-mkExportAvails :: ModuleName -> Bool -> GlobalRdrEnv -> [AvailInfo] -> ExportAvails
-mkExportAvails mod_name unqual_imp name_env avails
- = (mod_avail_env, entity_avail_env)
- where
- mod_avail_env = unitFM mod_name unqual_avails
-
- -- unqual_avails is the Avails that are visible in *unqualfied* form
- -- (1.4 Report, Section 5.1.1)
- -- For example, in
- -- import T hiding( f )
- -- we delete f from avails
-
- unqual_avails | not unqual_imp = [] -- Short cut when no unqualified imports
- | otherwise = mapMaybe prune avails
-
- prune (Avail n) | unqual_in_scope n = Just (Avail n)
- prune (Avail n) | otherwise = Nothing
- prune (AvailTC n ns) | null uqs = Nothing
- | otherwise = Just (AvailTC n uqs)
- where
- uqs = filter unqual_in_scope ns
-
- unqual_in_scope n = unQualInScope name_env n
-
- entity_avail_env = listToUFM [ (name,avail) | avail <- avails,
- name <- availNames avail]
-
-plusExportAvails :: ExportAvails -> ExportAvails -> ExportAvails
-plusExportAvails (m1, e1) (m2, e2)
- = (plusFM_C (++) m1 m2, plusAvailEnv e1 e2)
- -- ToDo: wasteful: we do this once for each constructor!
+ [] -> bale_out item
+ names -> succeed_with True names
+
+ check_item :: IE RdrName -> [Name]
+ check_item item
+ = case lookupOccEnv occ_env (rdrNameOcc (ieName item)) of
+ Nothing -> []
+ Just name -> filterAvail item name sub_env
\end{code}
Processing the export list.
-You might think that we should record things that appear in the export list
-as ``occurrences'' (using @addOccurrenceName@), but you'd be wrong.
-We do check (here) that they are in scope,
-but there is no need to slurp in their actual declaration
-(which is what @addOccurrenceName@ forces).
+You might think that we should record things that appear in the export
+list as ``occurrences'' (using @addOccurrenceName@), but you'd be
+wrong. We do check (here) that they are in scope, but there is no
+need to slurp in their actual declaration (which is what
+@addOccurrenceName@ forces).
-Indeed, doing so would big trouble when
-compiling @PrelBase@, because it re-exports @GHC@, which includes @takeMVar#@,
-whose type includes @ConcBase.StateAndSynchVar#@, and so on...
+Indeed, doing so would big trouble when compiling @PrelBase@, because
+it re-exports @GHC@, which includes @takeMVar#@, whose type includes
+@ConcBase.StateAndSynchVar#@, and so on...
\begin{code}
type ExportAccum -- The type of the accumulating parameter of
-- the main worker function in exportsFromAvail
- = ([ModuleName], -- 'module M's seen so far
+ = ([Module], -- 'module M's seen so far
ExportOccMap, -- Tracks exported occurrence names
- AvailEnv) -- The accumulated exported stuff, kept in an env
- -- so we can common-up related AvailInfos
+ NameSet) -- The accumulated exported stuff
+emptyExportAccum = ([], emptyOccEnv, emptyNameSet)
-type ExportOccMap = FiniteMap OccName (Name, RdrNameIE)
+type ExportOccMap = OccEnv (Name, IE RdrName)
-- Tracks what a particular exported OccName
-- in an export list refers to, and which item
-- it came from. It's illegal to export two distinct things
-- that have the same occurrence name
-exportsFromAvail :: ModuleName
- -> Maybe [RdrNameIE] -- Export spec
- -> ExportAvails
- -> GlobalRdrEnv
- -> RnMG Avails
+exportsFromAvail :: Bool -- False => no 'module M(..) where' header at all
+ -> Maybe [Located (IE RdrName)] -- Nothing => no explicit export list
+ -> RnM NameSet
-- Complains if two distinct exports have same OccName
-- Warns about identical exports.
-- Complains about exports items not in scope
-exportsFromAvail this_mod Nothing export_avails global_name_env
- = exportsFromAvail this_mod true_exports export_avails global_name_env
- where
- true_exports = Just $ if this_mod == mAIN_Name
- then [IEVar main_RDR_Unqual]
- -- export Main.main *only* unless otherwise specified,
- else [IEModuleContents this_mod]
- -- but for all other modules export everything.
-
-exportsFromAvail this_mod (Just export_items)
- (mod_avail_env, entity_avail_env)
- global_name_env
- = doptRn Opt_WarnDuplicateExports `thenRn` \ warn_dup_exports ->
- foldlRn (exports_from_item warn_dup_exports)
- ([], emptyFM, emptyAvailEnv) export_items
- `thenRn` \ (_, _, export_avail_map) ->
- let
- export_avails :: [AvailInfo]
- export_avails = nameEnvElts export_avail_map
- in
- returnRn export_avails
+exportsFromAvail explicit_mod exports
+ = do { TcGblEnv { tcg_rdr_env = rdr_env,
+ tcg_imports = imports } <- getGblEnv ;
+
+ -- If the module header is omitted altogether, then behave
+ -- as if the user had written "module Main(main) where..."
+ -- EXCEPT in interactive mode, when we behave as if he had
+ -- written "module Main where ..."
+ -- Reason: don't want to complain about 'main' not in scope
+ -- in interactive mode
+ ghci_mode <- getGhciMode ;
+ let { real_exports
+ | explicit_mod = exports
+ | ghci_mode == Interactive = Nothing
+ | otherwise = Just [noLoc (IEVar main_RDR_Unqual)] } ;
+ exports_from_avail real_exports rdr_env imports }
+
+
+exports_from_avail Nothing rdr_env imports
+ = -- Export all locally-defined things
+ -- We do this by filtering the global RdrEnv,
+ -- keeping only things that are locally-defined
+ return (mkNameSet [ gre_name gre
+ | gre <- globalRdrEnvElts rdr_env,
+ isLocalGRE gre ])
+
+exports_from_avail (Just items) rdr_env (ImportAvails { imp_env = imp_env })
+ = foldlM do_litem emptyExportAccum items `thenM` \ (_, _, exports) ->
+ returnM exports
where
- exports_from_item :: Bool -> ExportAccum -> RdrNameIE -> RnMG ExportAccum
+ sub_env :: NameEnv [Name] -- Classify each name by its parent
+ sub_env = mkSubNameEnv (foldModuleEnv unionNameSets emptyNameSet imp_env)
+
+ do_litem :: ExportAccum -> Located (IE RdrName) -> RnM ExportAccum
+ do_litem acc = addLocM (exports_from_item acc)
- exports_from_item warn_dups acc@(mods, occs, avails) ie@(IEModuleContents mod)
+ exports_from_item :: ExportAccum -> IE RdrName -> RnM ExportAccum
+ exports_from_item acc@(mods, occs, exports) ie@(IEModuleContents mod)
| mod `elem` mods -- Duplicate export of M
- = warnCheckRn warn_dups (dupModuleExport mod) `thenRn_`
- returnRn acc
+ = do { warn_dup_exports <- doptM Opt_WarnDuplicateExports ;
+ warnIf warn_dup_exports (dupModuleExport mod) ;
+ returnM acc }
| otherwise
- = case lookupFM mod_avail_env mod of
- Nothing -> failWithRn acc (modExportErr mod)
- Just mod_avails -> foldlRn (check_occs ie) occs mod_avails
- `thenRn` \ occs' ->
- let
- avails' = foldl addAvail avails mod_avails
- in
- returnRn (mod:mods, occs', avails')
-
- exports_from_item warn_dups acc@(mods, occs, avails) ie
- = lookupSrcName global_name_env (ieName ie) `thenRn` \ name ->
-
- -- See what's available in the current environment
- case lookupUFM entity_avail_env name of {
- Nothing -> -- Presumably this happens because lookupSrcName didn't find
- -- the name and returned an unboundName, which won't be in
- -- the entity_avail_env, of course
- WARN( not (isUnboundName name), ppr name )
- returnRn acc ;
-
- Just avail ->
-
- -- Filter out the bits we want
- case filterAvail ie avail of {
- Nothing -> -- Not enough availability
- failWithRn acc (exportItemErr ie) ;
-
- Just export_avail ->
-
- -- Phew! It's OK! Now to check the occurrence stuff!
- warnCheckRn (ok_item ie avail) (dodgyExportWarn ie) `thenRn_`
- check_occs ie occs export_avail `thenRn` \ occs' ->
- returnRn (mods, occs', addAvail avails export_avail)
- }}
-
-
-
-ok_item (IEThingAll _) (AvailTC _ [n]) = False
- -- This occurs when you import T(..), but
- -- only export T abstractly. The single [n]
- -- in the AvailTC is the type or class itself
-ok_item _ _ = True
-
-check_occs :: RdrNameIE -> ExportOccMap -> AvailInfo -> RnMG ExportOccMap
-check_occs ie occs avail
- = doptRn Opt_WarnDuplicateExports `thenRn` \ warn_dup_exports ->
- foldlRn (check warn_dup_exports) occs (availNames avail)
+ = case lookupModuleEnv imp_env mod of
+ Nothing -> addErr (modExportErr mod) `thenM_`
+ returnM acc
+ Just names
+ -> let
+ new_exports = filterNameSet (inScopeUnqual rdr_env) names
+ in
+
+ -- This check_occs not only finds conflicts between this item
+ -- and others, but also internally within this item. That is,
+ -- if 'M.x' is in scope in several ways, we'll have several
+ -- members of mod_avails with the same OccName.
+ check_occs ie occs (nameSetToList new_exports) `thenM` \ occs' ->
+ returnM (mod:mods, occs', exports `unionNameSets` new_exports)
+
+ exports_from_item acc@(mods, occs, exports) ie
+ = lookupGlobalOccRn (ieName ie) `thenM` \ name ->
+ if isUnboundName name then
+ returnM acc -- Avoid error cascade
+ else let
+ new_exports = filterAvail ie name sub_env
+ in
+ checkErr (not (null new_exports)) (exportItemErr ie) `thenM_`
+ checkForDodgyExport ie new_exports `thenM_`
+ check_occs ie occs new_exports `thenM` \ occs' ->
+ returnM (mods, occs', addListToNameSet exports new_exports)
+
+-------------------------------
+filterAvail :: IE RdrName -- Wanted
+ -> Name -- The Name of the ieName of the item
+ -> NameEnv [Name] -- Maps type/class names to their sub-names
+ -> [Name] -- Empty if even one thing reqd is missing
+
+filterAvail (IEVar _) n subs = [n]
+filterAvail (IEThingAbs _) n subs = [n]
+filterAvail (IEThingAll _) n subs = n : subNames subs n
+filterAvail (IEThingWith _ rdrs) n subs
+ | any isNothing mb_names = []
+ | otherwise = n : catMaybes mb_names
where
- check warn_dup occs name
- = case lookupFM occs name_occ of
- Nothing -> returnRn (addToFM occs name_occ (name, ie))
- Just (name', ie')
- | name == name' -> -- Duplicate export
- warnCheckRn warn_dup
- (dupExportWarn name_occ ie ie')
- `thenRn_` returnRn occs
+ env = mkOccEnv [(nameOccName s, s) | s <- subNames subs n]
+ mb_names = map (lookupOccEnv env . rdrNameOcc) rdrs
- | otherwise -> -- Same occ name but different names: an error
- failWithRn occs (exportClashErr name_occ ie ie')
+subNames :: NameEnv [Name] -> Name -> [Name]
+subNames env n = lookupNameEnv env n `orElse` []
+
+mkSubNameEnv :: NameSet -> NameEnv [Name]
+-- Maps types and classes to their constructors/classops respectively
+-- This mapping just makes it easier to deal with A(..) export items
+mkSubNameEnv names
+ = foldNameSet add_name emptyNameEnv names
+ where
+ add_name name env
+ | Just parent <- nameParent_maybe name
+ = extendNameEnv_C (\ns _ -> name:ns) env parent [name]
+ | otherwise = env
+
+-------------------------------
+inScopeUnqual :: GlobalRdrEnv -> Name -> Bool
+-- Checks whether the Name is in scope unqualified,
+-- regardless of whether it's ambiguous or not
+inScopeUnqual env n = any unQualOK (lookupGRE_Name env n)
+
+-------------------------------
+checkForDodgyExport :: IE RdrName -> [Name] -> RnM ()
+checkForDodgyExport ie@(IEThingAll tc) [n]
+ | isTcOcc (nameOccName n) = addWarn (dodgyExportWarn tc)
+ -- This occurs when you export T(..), but
+ -- only import T abstractly, or T is a synonym.
+ -- The single [n] is the type or class itself
+ | otherwise = addErr (exportItemErr ie)
+ -- This happes if you export x(..), which is bogus
+checkForDodgyExport _ _ = return ()
+
+-------------------------------
+check_occs :: IE RdrName -> ExportOccMap -> [Name] -> RnM ExportOccMap
+check_occs ie occs names
+ = foldlM check occs names
+ where
+ check occs name
+ = case lookupOccEnv occs name_occ of
+ Nothing -> returnM (extendOccEnv occs name_occ (name, ie))
+
+ Just (name', ie')
+ | name == name' -- Duplicate export
+ -> do { warn_dup_exports <- doptM Opt_WarnDuplicateExports ;
+ warnIf warn_dup_exports (dupExportWarn name_occ ie ie') ;
+ returnM occs }
+
+ | otherwise -- Same occ name but different names: an error
+ -> do { global_env <- getGlobalRdrEnv ;
+ addErr (exportClashErr global_env name name' ie ie') ;
+ returnM occs }
where
name_occ = nameOccName name
-
-mk_export_fn :: NameSet -> (Name -> Bool) -- True => exported
-mk_export_fn exported_names = \name -> name `elemNameSet` exported_names
\end{code}
+%*********************************************************
+%* *
+ Deprecations
+%* *
+%*********************************************************
+
+\begin{code}
+reportDeprecations :: TcGblEnv -> RnM ()
+reportDeprecations tcg_env
+ = ifOptM Opt_WarnDeprecations $
+ do { (eps,hpt) <- getEpsAndHpt
+ ; mapM_ (check hpt (eps_PIT eps)) all_gres }
+ where
+ used_names = findUses (tcg_dus tcg_env) emptyNameSet
+ all_gres = globalRdrEnvElts (tcg_rdr_env tcg_env)
+
+ check hpt pit (GRE {gre_name = name, gre_prov = Imported (imp_spec:_) _})
+ | name `elemNameSet` used_names
+ , Just deprec_txt <- lookupDeprec hpt pit name
+ = setSrcSpan (is_loc imp_spec) $
+ addWarn (sep [ptext SLIT("Deprecated use of") <+>
+ occNameFlavour (nameOccName name) <+>
+ quotes (ppr name),
+ (parens imp_msg),
+ (ppr deprec_txt) ])
+ where
+ name_mod = nameModule name
+ imp_mod = is_mod imp_spec
+ imp_msg = ptext SLIT("imported from") <+> ppr imp_mod <> extra
+ extra | imp_mod == name_mod = empty
+ | otherwise = ptext SLIT(", but defined in") <+> ppr name_mod
+
+ check hpt pit ok_gre = returnM () -- Local, or not used, or not deprectated
+ -- The Imported pattern-match: don't deprecate locally defined names
+ -- For a start, we may be exporting a deprecated thing
+ -- Also we may use a deprecated thing in the defn of another
+ -- deprecated things. We may even use a deprecated thing in
+ -- the defn of a non-deprecated thing, when changing a module's
+ -- interface
+
+lookupDeprec :: HomePackageTable -> PackageIfaceTable
+ -> Name -> Maybe DeprecTxt
+lookupDeprec hpt pit n
+ = case lookupIface hpt pit (nameModule n) of
+ Just iface -> mi_dep_fn iface n `seqMaybe` -- Bleat if the thing, *or
+ mi_dep_fn iface (nameParent n) -- its parent*, is deprec'd
+ Nothing
+ | isWiredInName n -> Nothing
+ -- We have not necessarily loaded the .hi file for a
+ -- wired-in name (yet), although we *could*.
+ -- And we never deprecate them
+
+ | otherwise -> pprPanic "lookupDeprec" (ppr n)
+ -- By now all the interfaces should have been loaded
+
+gre_is_used :: NameSet -> GlobalRdrElt -> Bool
+gre_is_used used_names gre = gre_name gre `elemNameSet` used_names
+\end{code}
+
+%*********************************************************
+%* *
+ Unused names
+%* *
+%*********************************************************
+
+\begin{code}
+reportUnusedNames :: Maybe [Located (IE RdrName)] -- Export list
+ -> TcGblEnv -> RnM ()
+reportUnusedNames export_decls gbl_env
+ = do { warnUnusedTopBinds unused_locals
+ ; warnUnusedModules unused_imp_mods
+ ; warnUnusedImports unused_imports
+ ; warnDuplicateImports dup_imps
+ ; printMinimalImports minimal_imports }
+ where
+ used_names, all_used_names :: NameSet
+ used_names = findUses (tcg_dus gbl_env) emptyNameSet
+ all_used_names = used_names `unionNameSets`
+ mkNameSet (mapCatMaybes nameParent_maybe (nameSetToList used_names))
+ -- A use of C implies a use of T,
+ -- if C was brought into scope by T(..) or T(C)
+
+ -- Collect the defined names from the in-scope environment
+ defined_names :: [GlobalRdrElt]
+ defined_names = globalRdrEnvElts (tcg_rdr_env gbl_env)
+
+ -- Note that defined_and_used, defined_but_not_used
+ -- are both [GRE]; that's why we need defined_and_used
+ -- rather than just all_used_names
+ defined_and_used, defined_but_not_used :: [GlobalRdrElt]
+ (defined_and_used, defined_but_not_used)
+ = partition (gre_is_used all_used_names) defined_names
+
+ -- Find the duplicate imports
+ dup_imps = filter is_dup defined_and_used
+ is_dup (GRE {gre_prov = Imported imp_spec True}) = not (isSingleton imp_spec)
+ is_dup other = False
+
+ -- Filter out the ones that are
+ -- (a) defined in this module, and
+ -- (b) not defined by a 'deriving' clause
+ -- The latter have an Internal Name, so we can filter them out easily
+ unused_locals :: [GlobalRdrElt]
+ unused_locals = filter is_unused_local defined_but_not_used
+ is_unused_local :: GlobalRdrElt -> Bool
+ is_unused_local gre = isLocalGRE gre && isExternalName (gre_name gre)
+
+ unused_imports :: [GlobalRdrElt]
+ unused_imports = filter unused_imp defined_but_not_used
+ unused_imp (GRE {gre_prov = Imported imp_specs True})
+ = not (all (module_unused . is_mod) imp_specs)
+ -- Don't complain about unused imports if we've already said the
+ -- entire import is unused
+ unused_imp other = False
+
+ -- To figure out the minimal set of imports, start with the things
+ -- that are in scope (i.e. in gbl_env). Then just combine them
+ -- into a bunch of avails, so they are properly grouped
+ --
+ -- BUG WARNING: this does not deal properly with qualified imports!
+ minimal_imports :: FiniteMap Module AvailEnv
+ minimal_imports0 = foldr add_expall emptyFM expall_mods
+ minimal_imports1 = foldr add_name minimal_imports0 defined_and_used
+ minimal_imports = foldr add_inst_mod minimal_imports1 direct_import_mods
+ -- The last line makes sure that we retain all direct imports
+ -- even if we import nothing explicitly.
+ -- It's not necessarily redundant to import such modules. Consider
+ -- module This
+ -- import M ()
+ --
+ -- The import M() is not *necessarily* redundant, even if
+ -- we suck in no instance decls from M (e.g. it contains
+ -- no instance decls, or This contains no code). It may be
+ -- that we import M solely to ensure that M's orphan instance
+ -- decls (or those in its imports) are visible to people who
+ -- import This. Sigh.
+ -- There's really no good way to detect this, so the error message
+ -- in RnEnv.warnUnusedModules is weakened instead
+
+ -- We've carefully preserved the provenance so that we can
+ -- construct minimal imports that import the name by (one of)
+ -- the same route(s) as the programmer originally did.
+ add_name (GRE {gre_name = n, gre_prov = Imported imp_specs _}) acc
+ = addToFM_C plusAvailEnv acc (is_mod (head imp_specs))
+ (unitAvailEnv (mk_avail n (nameParent_maybe n)))
+ add_name other acc
+ = acc
+
+ -- Modules mentioned as 'module M' in the export list
+ expall_mods = case export_decls of
+ Nothing -> []
+ Just es -> [m | L _ (IEModuleContents m) <- es]
+
+ -- This is really bogus. The idea is that if we see 'module M' in
+ -- the export list we must retain the import decls that drive it
+ -- If we aren't careful we might see
+ -- module A( module M ) where
+ -- import M
+ -- import N
+ -- and suppose that N exports everything that M does. Then we
+ -- must not drop the import of M even though N brings it all into
+ -- scope.
+ --
+ -- BUG WARNING: 'module M' exports aside, what if M.x is mentioned?!
+ --
+ -- The reason that add_expall is bogus is that it doesn't take
+ -- qualified imports into account. But it's an improvement.
+ add_expall mod acc = addToFM_C plusAvailEnv acc mod emptyAvailEnv
+
+ -- n is the name of the thing, p is the name of its parent
+ mk_avail n (Just p) = AvailTC p [p,n]
+ mk_avail n Nothing | isTcOcc (nameOccName n) = AvailTC n [n]
+ | otherwise = Avail n
+
+ add_inst_mod (mod,_,_) acc
+ | mod `elemFM` acc = acc -- We import something already
+ | otherwise = addToFM acc mod emptyAvailEnv
+ where
+ -- Add an empty collection of imports for a module
+ -- from which we have sucked only instance decls
+
+ imports = tcg_imports gbl_env
+
+ direct_import_mods :: [(Module, Maybe Bool, SrcSpan)]
+ -- See the type of the imp_mods for this triple
+ direct_import_mods = moduleEnvElts (imp_mods imports)
+
+ -- unused_imp_mods are the directly-imported modules
+ -- that are not mentioned in minimal_imports1
+ -- [Note: not 'minimal_imports', because that includes directly-imported
+ -- modules even if we use nothing from them; see notes above]
+ --
+ -- BUG WARNING: does not deal correctly with multiple imports of the same module
+ -- becuase direct_import_mods has only one entry per module
+ unused_imp_mods = [(mod,loc) | (mod,imp,loc) <- direct_import_mods,
+ not (mod `elemFM` minimal_imports1),
+ mod /= pRELUDE,
+ imp /= Just False]
+ -- The Just False part is not to complain about
+ -- import M (), which is an idiom for importing
+ -- instance declarations
+
+ module_unused :: Module -> Bool
+ module_unused mod = any (((==) mod) . fst) unused_imp_mods
+
+---------------------
+warnDuplicateImports :: [GlobalRdrElt] -> RnM ()
+warnDuplicateImports gres
+ = ifOptM Opt_WarnUnusedImports (mapM_ warn gres)
+ where
+ warn (GRE { gre_name = name, gre_prov = Imported imps _ })
+ = addWarn ((quotes (ppr name) <+> ptext SLIT("is imported more than once:"))
+ $$ nest 2 (vcat (map ppr imps)))
+
+
+-- ToDo: deal with original imports with 'qualified' and 'as M' clauses
+printMinimalImports :: FiniteMap Module AvailEnv -- Minimal imports
+ -> RnM ()
+printMinimalImports imps
+ = ifOptM Opt_D_dump_minimal_imports $ do {
+
+ mod_ies <- mappM to_ies (fmToList imps) ;
+ this_mod <- getModule ;
+ rdr_env <- getGlobalRdrEnv ;
+ ioToTcRn (do { h <- openFile (mkFilename this_mod) WriteMode ;
+ printForUser h (unQualInScope rdr_env)
+ (vcat (map ppr_mod_ie mod_ies)) })
+ }
+ where
+ mkFilename this_mod = moduleUserString this_mod ++ ".imports"
+ ppr_mod_ie (mod_name, ies)
+ | mod_name == pRELUDE
+ = empty
+ | null ies -- Nothing except instances comes from here
+ = ptext SLIT("import") <+> ppr mod_name <> ptext SLIT("() -- Instances only")
+ | otherwise
+ = ptext SLIT("import") <+> ppr mod_name <>
+ parens (fsep (punctuate comma (map ppr ies)))
+
+ to_ies (mod, avail_env) = mappM to_ie (availEnvElts avail_env) `thenM` \ ies ->
+ returnM (mod, ies)
+
+ to_ie :: AvailInfo -> RnM (IE Name)
+ -- The main trick here is that if we're importing all the constructors
+ -- we want to say "T(..)", but if we're importing only a subset we want
+ -- to say "T(A,B,C)". So we have to find out what the module exports.
+ to_ie (Avail n) = returnM (IEVar n)
+ to_ie (AvailTC n [m]) = ASSERT( n==m )
+ returnM (IEThingAbs n)
+ to_ie (AvailTC n ns)
+ = loadSrcInterface doc n_mod False `thenM` \ iface ->
+ case [xs | (m,as) <- mi_exports iface,
+ m == n_mod,
+ AvailTC x xs <- as,
+ x == nameOccName n] of
+ [xs] | all_used xs -> returnM (IEThingAll n)
+ | otherwise -> returnM (IEThingWith n (filter (/= n) ns))
+ other -> pprTrace "to_ie" (ppr n <+> ppr n_mod <+> ppr other) $
+ returnM (IEVar n)
+ where
+ all_used avail_occs = all (`elem` map nameOccName ns) avail_occs
+ doc = text "Compute minimal imports from" <+> ppr n
+ n_mod = nameModule n
+\end{code}
+
+
%************************************************************************
%* *
\subsection{Errors}
%************************************************************************
\begin{code}
-badImportItemErr mod from ie
- = sep [ptext SLIT("Module"), quotes (ppr mod), source_import,
+badImportItemErr iface imp_spec ie
+ = sep [ptext SLIT("Module"), quotes (ppr (is_mod imp_spec)), source_import,
ptext SLIT("does not export"), quotes (ppr ie)]
where
- source_import = case from of
- ImportByUserSource -> ptext SLIT("(hi-boot interface)")
- other -> empty
+ source_import | mi_boot iface = ptext SLIT("(hi-boot interface)")
+ | otherwise = empty
-dodgyImportWarn mod item = dodgyMsg (ptext SLIT("import")) item
-dodgyExportWarn item = dodgyMsg (ptext SLIT("export")) item
+dodgyImportWarn item = dodgyMsg (ptext SLIT("import")) item
+dodgyExportWarn item = dodgyMsg (ptext SLIT("export")) item
-dodgyMsg kind item@(IEThingAll tc)
- = sep [ ptext SLIT("The") <+> kind <+> ptext SLIT("item") <+> quotes (ppr item),
+dodgyMsg kind tc
+ = sep [ ptext SLIT("The") <+> kind <+> ptext SLIT("item") <+> quotes (ppr (IEThingAll tc)),
ptext SLIT("suggests that") <+> quotes (ppr tc) <+> ptext SLIT("has constructor or class methods"),
ptext SLIT("but it has none; it is a type synonym or abstract type or class") ]
= sep [ ptext SLIT("The export item") <+> quotes (ppr export_item),
ptext SLIT("attempts to export constructors or class methods that are not visible here") ]
-exportClashErr occ_name ie1 ie2
- = hsep [ptext SLIT("The export items"), quotes (ppr ie1)
- ,ptext SLIT("and"), quotes (ppr ie2)
- ,ptext SLIT("create conflicting exports for"), quotes (ppr occ_name)]
-
-dupDeclErr (n:ns)
- = vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr n),
- nest 4 (vcat (map ppr sorted_locs))]
+exportClashErr global_env name1 name2 ie1 ie2
+ = vcat [ ptext SLIT("Conflicting exports for") <+> quotes (ppr occ) <> colon
+ , ppr_export ie1 name1
+ , ppr_export ie2 name2 ]
where
- sorted_locs = sortLt occ'ed_before (map nameSrcLoc (n:ns))
- occ'ed_before a b = LT == compare a b
+ occ = nameOccName name1
+ ppr_export ie name = nest 2 (quotes (ppr ie) <+> ptext SLIT("exports") <+>
+ quotes (ppr name) <+> pprNameProvenance (get_gre name))
+
+ -- get_gre finds a GRE for the Name, so that we can show its provenance
+ get_gre name
+ = case lookupGRE_Name global_env name of
+ (gre:_) -> gre
+ [] -> pprPanic "exportClashErr" (ppr name)
+
+addDupDeclErr :: [Name] -> TcRn ()
+addDupDeclErr names
+ = addErrAt big_loc $
+ vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr name1),
+ ptext SLIT("Declared at:") <+> vcat (map ppr sorted_locs)]
+ where
+ locs = map nameSrcLoc names
+ big_loc = foldr1 combineSrcSpans (map srcLocSpan locs)
+ name1 = head names
+ sorted_locs = sortLe (<=) (sortLe (<=) locs)
dupExportWarn occ_name ie1 ie2
= hsep [quotes (ppr occ_name),
= hsep [ptext SLIT("Duplicate"),
quotes (ptext SLIT("Module") <+> ppr mod),
ptext SLIT("in export list")]
+
+moduleDeprec mod txt
+ = sep [ ptext SLIT("Module") <+> quotes (ppr mod) <+> ptext SLIT("is deprecated:"),
+ nest 4 (ppr txt) ]
\end{code}
projects / ghc-hetmet.git / blobdiff