\begin{code}
module RnNames (
rnImports, importsFromLocalDecls, exportsFromAvail,
- reportUnusedNames
+ reportUnusedNames, mkModDeps, exportsToAvails
) where
#include "HsVersions.h"
-import {-# SOURCE #-} RnHiFiles ( loadInterface )
-
import CmdLineOpts ( DynFlag(..) )
-
-import HsSyn ( HsDecl(..), IE(..), ieName, ImportDecl(..),
- ForeignDecl(..),
- collectLocatedHsBinders, tyClDeclNames
+import HsSyn ( IE(..), ieName, ImportDecl(..), LImportDecl,
+ ForeignDecl(..), HsGroup(..),
+ collectGroupBinders, tyClDeclNames
)
-import RdrHsSyn ( RdrNameIE, RdrNameImportDecl, RdrNameHsDecl )
import RnEnv
+import IfaceEnv ( lookupOrig, newGlobalBinder )
+import LoadIface ( loadSrcInterface )
import TcRnMonad
import FiniteMap
-import PrelNames ( pRELUDE_Name, mAIN_Name, isBuiltInSyntaxName )
-import Module ( Module, ModuleName, moduleName,
- moduleNameUserString,
- unitModuleEnvByName, lookupModuleEnvByName,
- moduleEnvElts )
-import Name ( Name, nameSrcLoc, nameOccName, nameModule )
+import PrelNames ( pRELUDE_Name, isBuiltInSyntaxName, isUnboundName,
+ main_RDR_Unqual )
+import Module ( Module, ModuleName, moduleName, mkPackageModule,
+ moduleNameUserString, isHomeModule,
+ unitModuleEnvByName, unitModuleEnv,
+ lookupModuleEnvByName, moduleEnvElts )
+import Name ( Name, nameSrcLoc, nameOccName, nameModuleName,
+ nameParent, nameParent_maybe, isExternalName )
import NameSet
import NameEnv
-import OccName ( OccName, dataName, isTcOcc )
-import HscTypes ( Provenance(..), ImportReason(..), GlobalRdrEnv,
- GenAvailInfo(..), AvailInfo, Avails, IsBootInterface,
- availName, availNames, availsToNameSet,
- Deprecations(..), ModIface(..),
- GlobalRdrElt(..), unQualInScope, isLocalGRE
+import OccName ( OccName, srcDataName, isTcOcc )
+import HscTypes ( GenAvailInfo(..), AvailInfo, Avails, GhciMode(..),
+ IsBootInterface, IfaceExport,
+ availName, availNames, availsToNameSet, unQualInScope,
+ Deprecs(..), ModIface(..), Dependencies(..)
)
-import RdrName ( rdrNameOcc, setRdrNameSpace, emptyRdrEnv, foldRdrEnv, isQual )
-import SrcLoc ( noSrcLoc )
+import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace,
+ GlobalRdrEnv, mkGlobalRdrEnv, GlobalRdrElt(..),
+ emptyGlobalRdrEnv, plusGlobalRdrEnv, globalRdrEnvElts,
+ unQualOK, lookupGRE_Name,
+ Provenance(..), ImportSpec(..),
+ isLocalGRE, pprNameProvenance )
import Outputable
-import Maybes ( maybeToBool, catMaybes )
+import Maybes ( isJust, isNothing, catMaybes, mapCatMaybes )
+import SrcLoc ( noSrcLoc, Located(..), mkGeneralSrcSpan,
+ unLoc, noLoc )
import ListSetOps ( removeDups )
import Util ( sortLt, notNull )
-import List ( partition )
+import List ( partition, insert )
import IO ( openFile, IOMode(..) )
\end{code}
%************************************************************************
\begin{code}
-rnImports :: [RdrNameImportDecl]
- -> TcRn m (GlobalRdrEnv, ImportAvails)
+rnImports :: [LImportDecl RdrName]
+ -> RnM (GlobalRdrEnv, ImportAvails)
rnImports imports
= -- PROCESS IMPORT DECLS
-- Do the non {- SOURCE -} ones first, so that we get a helpful
-- warning for {- SOURCE -} ones that are unnecessary
getModule `thenM` \ this_mod ->
- getSrcLocM `thenM` \ loc ->
doptM Opt_NoImplicitPrelude `thenM` \ opt_no_prelude ->
let
- all_imports = mk_prel_imports this_mod loc opt_no_prelude ++ imports
+ all_imports = mk_prel_imports this_mod opt_no_prelude ++ imports
(source, ordinary) = partition is_source_import all_imports
- is_source_import (ImportDecl _ is_boot _ _ _ _) = is_boot
+ is_source_import (L _ (ImportDecl _ is_boot _ _ _)) = is_boot
- get_imports = importsFromImportDecl (moduleName this_mod)
+ get_imports = importsFromImportDecl this_mod
in
mappM get_imports ordinary `thenM` \ stuff1 ->
mappM get_imports source `thenM` \ stuff2 ->
let
(imp_gbl_envs, imp_avails) = unzip (stuff1 ++ stuff2)
gbl_env :: GlobalRdrEnv
- gbl_env = foldr plusGlobalRdrEnv emptyRdrEnv imp_gbl_envs
+ gbl_env = foldr plusGlobalRdrEnv emptyGlobalRdrEnv imp_gbl_envs
all_avails :: ImportAvails
all_avails = foldr plusImportAvails emptyImportAvails imp_avails
-- 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 this_mod loc no_prelude
+ mk_prel_imports this_mod no_prelude
| moduleName this_mod == pRELUDE_Name
|| explicit_prelude_import
|| no_prelude
= []
- | otherwise = [preludeImportDecl loc]
+ | otherwise = [preludeImportDecl]
explicit_prelude_import
- = notNull [ () | (ImportDecl mod _ _ _ _ _) <- imports,
- mod == pRELUDE_Name ]
+ = notNull [ () | L _ (ImportDecl mod _ _ _ _) <- imports,
+ unLoc mod == pRELUDE_Name ]
-preludeImportDecl loc
- = ImportDecl pRELUDE_Name
+preludeImportDecl
+ = L loc $
+ ImportDecl (L loc pRELUDE_Name)
False {- Not a boot interface -}
False {- Not qualified -}
Nothing {- No "as" -}
Nothing {- No import list -}
- loc
+ where
+ loc = mkGeneralSrcSpan FSLIT("Implicit import declaration")
\end{code}
\begin{code}
-importsFromImportDecl :: ModuleName
- -> RdrNameImportDecl
- -> TcRn m (GlobalRdrEnv, ImportAvails)
+importsFromImportDecl :: Module
+ -> LImportDecl RdrName
+ -> RnM (GlobalRdrEnv, ImportAvails)
-importsFromImportDecl this_mod_name
- (ImportDecl imp_mod_name is_boot qual_only as_mod import_spec iloc)
- = addSrcLoc iloc $
- let
- doc = ppr imp_mod_name <+> ptext SLIT("is directly imported")
- in
+importsFromImportDecl this_mod
+ (L loc (ImportDecl loc_imp_mod_name want_boot qual_only as_mod imp_details))
+ =
+ addSrcSpan loc $
-- If there's an error in loadInterface, (e.g. interface
-- file not found) we get lots of spurious errors from 'filterImports'
- recoverM (returnM Nothing)
- (loadInterface doc imp_mod_name (ImportByUser is_boot) `thenM` \ iface ->
- returnM (Just iface)) `thenM` \ mb_iface ->
+ let
+ imp_mod_name = unLoc loc_imp_mod_name
+ this_mod_name = moduleName this_mod
+ 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 )
- case mb_iface of {
- Nothing -> returnM (emptyRdrEnv, emptyImportAvails ) ;
- Just iface ->
+ -- 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
- imp_mod = mi_module iface
- avails_by_module = mi_exports iface
- deprecs = mi_deprecs iface
- dir_imp = unitModuleEnvByName imp_mod_name (imp_mod, import_all import_spec)
-
- 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_name
-- 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
-- import {-# SOURCE #-} A( AType )
--
-- then you'll get a 'B does not export AType' message. Oh well.
+ in
+ exportsToAvails filtered_exports `thenM` \ avails ->
+
+ -- Filter the imports according to the import list
+ filterImports imp_mod want_boot imp_details avails `thenM` \ (filtered_avails, explicits) ->
+
+ let
+ -- Compute new transitive dependencies
+ orphans | is_orph = insert imp_mod_name (dep_orphs deps)
+ | otherwise = dep_orphs deps
+
+ (dependent_mods, dependent_pkgs)
+ | isHomeModule imp_mod
+ = -- Imported module is from the home package
+ -- Take its dependent modules and
+ -- (a) remove this_mod (might be there as a hi-boot)
+ -- (b) add imp_mod itself
+ -- Take its dependent packages unchanged
+ ((imp_mod_name, want_boot) : filter not_self (dep_mods deps), dep_pkgs deps)
+
+ | otherwise
+ = -- Imported module is from another package
+ -- Dump the dependent modules
+ -- Add the package imp_mod comes from to the dependent packages
+ -- from imp_mod
+ ([], insert (mi_package iface) (dep_pkgs deps))
+
+ not_self (m, _) = m /= this_mod_name
+
+ 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])
+
+ qual_mod_name = case as_mod of
+ Nothing -> imp_mod_name
+ Just another_name -> another_name
+
+ -- 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.
+ imp_spec = ImportSpec { is_mod = imp_mod_name, is_qual = qual_only,
+ is_loc = loc, is_as = qual_mod_name }
+ mk_deprec = mi_dep_fn iface
+ gres = [ GRE { gre_name = name,
+ gre_prov = Imported [imp_spec] (name `elemNameSet` explicits),
+ gre_deprec = mk_deprec name }
+ | avail <- filtered_avails, name <- availNames avail ]
+ gbl_env = mkGlobalRdrEnv gres
+
+ avail_env = mkAvailEnv filtered_avails
+ imports = ImportAvails {
+ imp_qual = unitModuleEnvByName qual_mod_name avail_env,
+ imp_env = avail_env,
+ imp_mods = unitModuleEnv imp_mod (imp_mod, import_all),
+ imp_orphs = orphans,
+ imp_dep_mods = mkModDeps dependent_mods,
+ imp_dep_pkgs = dependent_pkgs }
in
-- Complain if we import a deprecated module
other -> returnM ()
) `thenM_`
- -- Filter the imports according to the import list
- filterImports imp_mod_name is_boot import_spec avails `thenM` \ (filtered_avails, explicits) ->
-
- let
- unqual_imp = not qual_only -- Maybe want unqualified names
- qual_mod = case as_mod of
- Nothing -> imp_mod_name
- Just another_name -> another_name
-
- mk_prov name = NonLocalDef (UserImport imp_mod iloc (name `elemNameSet` explicits))
- gbl_env = mkGlobalRdrEnv qual_mod unqual_imp mk_prov filtered_avails deprecs
- imports = mkImportAvails qual_mod unqual_imp gbl_env filtered_avails
- in
- returnM (gbl_env, imports { imp_mods = dir_imp})
- }
+ returnM (gbl_env, imports)
-import_all (Just (False, _)) = False -- Imports are spec'd explicitly
-import_all other = True -- Everything is imported
+exportsToAvails :: [IfaceExport] -> TcRnIf gbl lcl Avails
+exportsToAvails exports
+ = do { avails_by_module <- mappM do_one exports
+ ; return (concat avails_by_module) }
+ where
+ do_one (mod_name, exports) = mapM (do_avail mod_name) exports
+ do_avail mod_nm (Avail n) = do { n' <- lookupOrig mod_nm n;
+ ; return (Avail n') }
+ do_avail mod_nm (AvailTC n ns) = do { n' <- lookupOrig mod_nm n
+ ; ns' <- mappM (lookup_sub n') ns
+ ; return (AvailTC n' ns') }
+ where
+ mod = mkPackageModule mod_nm -- Not necessarily right yet
+ lookup_sub parent occ = newGlobalBinder mod occ (Just parent) noSrcLoc
+ -- Hack alert! Notice the newGlobalBinder. It 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 only suck in the binding site 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}
Complain about duplicate bindings
\begin{code}
-importsFromLocalDecls :: [RdrNameHsDecl]
- -> TcRn m (GlobalRdrEnv, ImportAvails)
-importsFromLocalDecls decls
- = getModule `thenM` \ this_mod ->
- mappM (getLocalDeclBinders this_mod) decls `thenM` \ avails_s ->
+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
- avails = concat avails_s
-
all_names :: [Name] -- All the defns; no dups eliminated
all_names = [name | avail <- avails, name <- availNames avail]
doptM Opt_NoImplicitPrelude `thenM` \ implicit_prelude ->
let
- mod_name = moduleName this_mod
- unqual_imp = True -- Want unqualified names
- mk_prov n = LocalDef -- Provenance is local
-
- gbl_env = mkGlobalRdrEnv mod_name unqual_imp mk_prov avails NoDeprecs
- -- NoDeprecs: don't complain about locally defined names
+ mod_name = moduleName this_mod
+ prov = LocalDef mod_name
+ gbl_env = mkGlobalRdrEnv gres
+ gres = [ GRE { gre_name = name, gre_prov = prov, gre_deprec = Nothing}
+ | name <- all_names]
+ -- gre_deprecs = Nothing: 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
-- 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 type,
+ -- 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 Base and Tuple.
+ -- 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
-- defn of gbl_env 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. Sigh.
- -- It doesn't matter because it only affects the Data.Tuple really.
+ -- 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.
- imports = mkImportAvails mod_name unqual_imp gbl_env avails'
+
avails' | implicit_prelude = filter not_built_in_syntax avails
| otherwise = avails
not_built_in_syntax a = not (all isBuiltInSyntaxName (availNames a))
-- Only filter it if all the names of the avail are built-in
-- In particular, lists have (:) which is not built in syntax
- -- so we don't filter it out.
+ -- so we don't filter it out. [Sept 03: wrong: see isBuiltInSyntaxName]
+
+ avail_env = mkAvailEnv avails'
+ imports = emptyImportAvails {
+ imp_qual = unitModuleEnv this_mod avail_env,
+ imp_env = avail_env
+ }
in
returnM (gbl_env, imports)
\end{code}
%* *
%*********************************************************
-@getLocalDeclBinders@ returns the names for a @RdrNameHsDecl@. It's
-used for both source code (from @importsFromLocalDecls@) and interface
-files (@loadDecl@ calls @getTyClDeclBinders@).
+@getLocalDeclBinders@ returns the names for an @HsDecl@. It's
+used for source code.
*** See "THE NAMING STORY" in HsDecls ****
\begin{code}
-getLocalDeclBinders :: Module -> RdrNameHsDecl -> TcRn m [AvailInfo]
-getLocalDeclBinders mod (TyClD tycl_decl)
+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.
- mapM new (tyClDeclNames tycl_decl) `thenM` \ names@(main_name:_) ->
- returnM [AvailTC main_name names]
- where
- new (nm,loc) = newTopBinder mod nm loc
-getLocalDeclBinders mod (ValD binds)
- = mappM new (collectLocatedHsBinders binds) `thenM` \ avails ->
- returnM avails
+ mappM new_tc tycl_decls `thenM` \ tc_avails ->
+ mappM new_simple (for_hs_bndrs ++ val_hs_bndrs) `thenM` \ simple_avails ->
+ returnM (tc_avails ++ simple_avails)
where
- new (rdr_name, loc) = newTopBinder mod rdr_name loc `thenM` \ name ->
+ new_simple rdr_name = newTopSrcBinder mod Nothing rdr_name `thenM` \ name ->
returnM (Avail name)
-getLocalDeclBinders mod (ForD (ForeignImport nm _ _ _ loc))
- = newTopBinder mod nm loc `thenM` \ name ->
- returnM [Avail name]
-getLocalDeclBinders mod (ForD _)
- = returnM []
-
-getLocalDeclBinders mod (FixD _) = returnM []
-getLocalDeclBinders mod (DeprecD _) = returnM []
-getLocalDeclBinders mod (DefD _) = returnM []
-getLocalDeclBinders mod (InstD _) = returnM []
-getLocalDeclBinders mod (RuleD _) = returnM []
+ 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
+filterImports :: Module -- The module being imported
-> IsBootInterface -- Tells whether it's a {-# SOURCE #-} import
- -> Maybe (Bool, [RdrNameIE]) -- Import spec; True => hiding
+ -> Maybe (Bool, [Located (IE RdrName)]) -- Import spec; True => hiding
-> [AvailInfo] -- What's available
- -> TcRn m ([AvailInfo], -- What's imported
+ -> RnM ([AvailInfo], -- What's imported
NameSet) -- What was imported explicitly
-- Complains if import spec mentions things that the module doesn't export
= returnM (imports, emptyNameSet)
filterImports mod from (Just (want_hiding, import_items)) total_avails
- = mappM get_item import_items `thenM` \ avails_w_explicits_s ->
+ = mappM (addLocM get_item) import_items `thenM` \ avails_w_explicits_s ->
let
(item_avails, explicits_s) = unzip (concat avails_w_explicits_s)
explicits = foldl addListToNameSet emptyNameSet explicits_s
bale_out item = addErr (badImportItemErr mod from item) `thenM_`
returnM []
- get_item :: RdrNameIE -> TcRn m [(AvailInfo, [Name])]
+ get_item :: IE RdrName -> RnM [(AvailInfo, [Name])]
-- Empty list for a bad item.
-- Singleton is typical case.
-- Can have two when we are hiding, and mention C which might be
-- The [Name] is the list of explicitly-mentioned names
get_item item@(IEModuleContents _) = bale_out item
- get_item item@(IEThingAll _)
+ 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
- ifOptM Opt_WarnMisc (addWarn (dodgyImportWarn mod item)) `thenM_`
+ ifOptM Opt_WarnMisc (addWarn (dodgyImportWarn mod tc)) `thenM_`
returnM [(avail, [availName avail])]
Just avail -> returnM [(avail, [availName avail])]
avails -> returnM [(a, []) | a <- avails]
-- The 'explicits' list is irrelevant when hiding
where
- data_n = setRdrNameSpace n dataName
+ data_n = setRdrNameSpace n srcDataName
get_item item
= case check_item item of
Just avail -> returnM [(avail, availNames avail)]
check_item item
- | not (maybeToBool maybe_in_import_avails) ||
- not (maybeToBool maybe_filtered_avail)
+ | isNothing maybe_in_import_avails ||
+ isNothing maybe_filtered_avail
= Nothing
| otherwise
\end{code}
\begin{code}
-filterAvail :: RdrNameIE -- Wanted
+filterAvail :: IE RdrName -- Wanted
-> AvailInfo -- Available
-> Maybe AvailInfo -- Resulting available;
-- Nothing if (any of the) wanted stuff isn't there
-- so we can common-up related AvailInfos
emptyExportAccum = ([], emptyFM, emptyAvailEnv)
-type ExportOccMap = FiniteMap OccName (Name, RdrNameIE)
+type ExportOccMap = FiniteMap OccName (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 :: Maybe [RdrNameIE] -> TcRn m Avails
+exportsFromAvail :: Bool -- False => no 'module M(..) where' header at all
+ -> Maybe [Located (IE RdrName)] -- Nothing => no explicit export list
+ -> RnM Avails
-- Complains if two distinct exports have same OccName
-- Warns about identical exports.
-- Complains about exports items not in scope
-exportsFromAvail Nothing
- = do { this_mod <- getModule ;
- if moduleName this_mod == mAIN_Name then
- return []
- -- Export nothing; Main.$main is automatically exported
- else
- exportsFromAvail (Just [IEModuleContents (moduleName this_mod)])
- -- but for all other modules export everything.
- }
-
-exportsFromAvail (Just exports)
- = do { TcGblEnv { tcg_imports = imports } <- getGblEnv ;
- warn_dup_exports <- doptM Opt_WarnDuplicateExports ;
- exports_from_avail exports warn_dup_exports imports }
-
-exports_from_avail export_items warn_dup_exports
- (ImportAvails { imp_unqual = mod_avail_env,
- imp_env = entity_avail_env })
- = foldlM exports_from_item emptyExportAccum
+
+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@(ImportAvails { imp_env = entity_avail_env })
+ = -- Export all locally-defined things
+ -- We do this by filtering the global RdrEnv,
+ -- keeping only things that are (a) qualified,
+ -- (b) locally defined, (c) a 'main' name
+ -- Then we look up in the entity-avail-env
+ return [ lookupAvailEnv entity_avail_env name
+ | gre <- globalRdrEnvElts rdr_env,
+ isLocalGRE gre,
+ let name = gre_name gre,
+ isNothing (nameParent_maybe name) -- Main things only
+ ]
+
+exports_from_avail (Just export_items) rdr_env
+ (ImportAvails { imp_qual = mod_avail_env,
+ imp_env = entity_avail_env })
+ = foldlM (exports_from_litem) emptyExportAccum
export_items `thenM` \ (_, _, export_avail_map) ->
returnM (nameEnvElts export_avail_map)
where
- exports_from_item :: ExportAccum -> RdrNameIE -> TcRn m ExportAccum
+ exports_from_litem :: ExportAccum -> Located (IE RdrName) -> RnM ExportAccum
+ exports_from_litem acc = addLocM (exports_from_item acc)
+ exports_from_item :: ExportAccum -> IE RdrName -> RnM ExportAccum
exports_from_item acc@(mods, occs, avails) ie@(IEModuleContents mod)
| mod `elem` mods -- Duplicate export of M
- = warnIf warn_dup_exports (dupModuleExport mod) `thenM_`
- returnM acc
+ = do { warn_dup_exports <- doptM Opt_WarnDuplicateExports ;
+ warnIf warn_dup_exports (dupModuleExport mod) ;
+ returnM acc }
| otherwise
= case lookupModuleEnvByName mod_avail_env mod of
- Nothing -> addErr (modExportErr mod) `thenM_`
- returnM acc
- Just mod_avails
- -> foldlM (check_occs warn_dup_exports ie)
- occs mod_avails `thenM` \ occs' ->
- let
+ Nothing -> addErr (modExportErr mod) `thenM_`
+ returnM acc
+
+ Just avail_env
+ -> let
+ mod_avails = [ filtered_avail
+ | avail <- availEnvElts avail_env,
+ let mb_avail = filter_unqual rdr_env avail,
+ isJust mb_avail,
+ let Just filtered_avail = mb_avail]
+
avails' = foldl addAvail avails mod_avails
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.
+
+ foldlM (check_occs ie) occs mod_avails `thenM` \ occs' ->
returnM (mod:mods, occs', avails')
exports_from_item acc@(mods, occs, avails) ie
- = lookupGRE (ieName ie) `thenM` \ mb_gre ->
- case mb_gre of {
- Nothing -> addErr (unknownNameErr (ieName ie)) `thenM_`
- returnM acc ;
- Just gre ->
-
+ = lookupGlobalOccRn (ieName ie) `thenM` \ name ->
+ if isUnboundName name then
+ returnM acc -- Avoid error cascade
+ else
-- Get the AvailInfo for the parent of the specified name
- case lookupAvailEnv entity_avail_env (gre_parent gre) of {
- Nothing -> pprPanic "exportsFromAvail"
- ((ppr (ieName ie)) <+> ppr gre) ;
- Just avail ->
-
+ let
+ parent = nameParent name
+ avail = lookupAvailEnv entity_avail_env parent
+ in
-- Filter out the bits we want
case filterAvail ie avail of {
Nothing -> -- Not enough availability
Just export_avail ->
-- Phew! It's OK! Now to check the occurrence stuff!
- warnIf (not (ok_item ie avail)) (dodgyExportWarn ie) `thenM_`
- check_occs warn_dup_exports ie occs export_avail `thenM` \ occs' ->
+ checkForDodgyExport ie avail `thenM_`
+ check_occs ie occs export_avail `thenM` \ occs' ->
returnM (mods, occs', addAvail avails export_avail)
- }}}
-
+ }
+
+
+-------------------------------
+filter_unqual :: GlobalRdrEnv -> AvailInfo -> Maybe AvailInfo
+-- Filter the Avail by what's in scope unqualified
+filter_unqual env (Avail n)
+ | in_scope env n = Just (Avail n)
+ | otherwise = Nothing
+filter_unqual env (AvailTC n ns)
+ | not (null ns') = Just (AvailTC n ns')
+ | otherwise = Nothing
+ where
+ ns' = filter (in_scope env) ns
+in_scope :: GlobalRdrEnv -> Name -> Bool
+-- Checks whether the Name is in scope unqualified,
+-- regardless of whether it's ambiguous or not
+in_scope env n = any unQualOK (lookupGRE_Name env n)
-ok_item (IEThingAll _) (AvailTC _ [n]) = False
+-------------------------------
+checkForDodgyExport :: IE RdrName -> AvailInfo -> RnM ()
+checkForDodgyExport (IEThingAll tc) (AvailTC _ [n]) = addWarn (dodgyExportWarn tc)
-- 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
+checkForDodgyExport _ _ = return ()
-check_occs :: Bool -> RdrNameIE -> ExportOccMap -> AvailInfo -> TcRn m ExportOccMap
-check_occs warn_dup_exports ie occs avail
+-------------------------------
+check_occs :: IE RdrName -> ExportOccMap -> AvailInfo -> RnM ExportOccMap
+check_occs ie occs avail
= foldlM check occs (availNames avail)
where
check occs name
= case lookupFM occs name_occ of
- Nothing -> returnM (addToFM occs name_occ (name, ie))
+ Nothing -> returnM (addToFM occs name_occ (name, ie))
+
Just (name', ie')
- | name == name' -> -- Duplicate export
- warnIf warn_dup_exports
- (dupExportWarn name_occ ie ie')
- `thenM_` returnM occs
-
- | otherwise -> -- Same occ name but different names: an error
- addErr (exportClashErr name_occ ie ie') `thenM_`
- returnM occs
+ | 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
\end{code}
%*********************************************************
\begin{code}
-reportUnusedNames :: TcGblEnv
- -> NameSet -- Used in this module
- -> TcRn m ()
-reportUnusedNames gbl_env used_names
- = warnUnusedModules unused_imp_mods `thenM_`
- warnUnusedTopBinds bad_locals `thenM_`
- warnUnusedImports bad_imports `thenM_`
+reportUnusedNames :: TcGblEnv -> RnM ()
+reportUnusedNames gbl_env
+ = warnUnusedModules unused_imp_mods `thenM_`
+ warnUnusedTopBinds bad_locals `thenM_`
+ warnUnusedImports bad_imports `thenM_`
printMinimalImports minimal_imports
where
- direct_import_mods :: [ModuleName]
- direct_import_mods = map (moduleName . fst)
- (moduleEnvElts (imp_mods (tcg_imports gbl_env)))
-
- -- Now, a use of C implies a use of T,
- -- if C was brought into scope by T(..) or T(C)
- really_used_names :: NameSet
- really_used_names = used_names `unionNameSets`
- mkNameSet [ gre_parent gre
- | gre <- defined_names,
- gre_name gre `elemNameSet` used_names]
+ 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
- -- Look for the qualified ones only, else get duplicates
defined_names :: [GlobalRdrElt]
- defined_names = foldRdrEnv add [] (tcg_rdr_env gbl_env)
- add rdr_name ns acc | isQual rdr_name = ns ++ acc
- | otherwise = acc
+ defined_names = globalRdrEnvElts (tcg_rdr_env gbl_env)
defined_and_used, defined_but_not_used :: [GlobalRdrElt]
- (defined_and_used, defined_but_not_used) = partition used defined_names
- used gre = gre_name gre `elemNameSet` really_used_names
+ (defined_and_used, defined_but_not_used) = partition is_used defined_names
+
+ is_used gre = gre_name gre `elemNameSet` all_used_names
- -- Filter out the ones only defined implicitly
+ -- 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
bad_locals :: [GlobalRdrElt]
- bad_locals = filter isLocalGRE defined_but_not_used
+ bad_locals = filter is_bad defined_but_not_used
+ is_bad :: GlobalRdrElt -> Bool
+ is_bad gre = isLocalGRE gre && isExternalName (gre_name gre)
bad_imports :: [GlobalRdrElt]
bad_imports = filter bad_imp defined_but_not_used
- bad_imp (GRE {gre_prov = NonLocalDef (UserImport mod _ True)}) = not (module_unused mod)
- bad_imp other = False
+ bad_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
+ bad_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
-- 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_parent = p,
- gre_prov = NonLocalDef (UserImport m _ _)}) acc
- = addToFM_C plusAvailEnv acc (moduleName m)
- (unitAvailEnv (mk_avail n p))
+ 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
-- n is the name of the thing, p is the name of its parent
- mk_avail n p | n/=p = AvailTC p [p,n]
- | isTcOcc (nameOccName p) = AvailTC n [n]
- | otherwise = Avail n
+ 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 m acc
| m `elemFM` acc = acc -- We import something already
-- 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 :: [ModuleName]
+ direct_import_mods = map (moduleName . fst)
+ (moduleEnvElts (imp_mods imports))
+
+ hasEmptyImpList :: ModuleName -> Bool
+ hasEmptyImpList m =
+ case lookupModuleEnvByName (imp_mods imports) m of
+ Just (_,Just x) -> not x
+ _ -> False
+
-- unused_imp_mods are the directly-imported modules
-- that are not mentioned in minimal_imports1
- -- [Note: not 'minimal_imports', because that includes direcly-imported
+ -- [Note: not 'minimal_imports', because that includes directly-imported
-- modules even if we use nothing from them; see notes above]
unused_imp_mods = [m | m <- direct_import_mods,
- not (maybeToBool (lookupFM minimal_imports1 m)),
- m /= pRELUDE_Name]
+ isNothing (lookupFM minimal_imports1 m),
+ m /= pRELUDE_Name,
+ not (hasEmptyImpList m)]
+ -- hasEmptyImpList arranges not to complain about
+ -- import M (), which is an idiom for importing
+ -- instance declarations
- module_unused :: Module -> Bool
- module_unused mod = moduleName mod `elem` unused_imp_mods
+ module_unused :: ModuleName -> Bool
+ module_unused mod = mod `elem` unused_imp_mods
-- ToDo: deal with original imports with 'qualified' and 'as M' clauses
printMinimalImports :: FiniteMap ModuleName AvailEnv -- Minimal imports
- -> TcRn m ()
+ -> RnM ()
printMinimalImports imps
= ifOptM Opt_D_dump_minimal_imports $ do {
to_ies (mod, avail_env) = mappM to_ie (availEnvElts avail_env) `thenM` \ ies ->
returnM (mod, ies)
- to_ie :: AvailInfo -> TcRn m (IE Name)
+ 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 (AvailTC n [m]) = ASSERT( n==m )
returnM (IEThingAbs n)
to_ie (AvailTC n ns)
- = loadInterface (text "Compute minimal imports from" <+> ppr n_mod)
- n_mod ImportBySystem `thenM` \ iface ->
+ = loadSrcInterface doc n_mod False `thenM` \ iface ->
case [xs | (m,as) <- mi_exports iface,
m == n_mod,
AvailTC x xs <- as,
- x == n] of
- [xs] | all (`elem` ns) xs -> returnM (IEThingAll n)
- | otherwise -> returnM (IEThingWith n (filter (/= n) ns))
- other -> pprTrace "to_ie" (ppr n <+> ppr (nameModule n) <+> ppr other) $
- returnM (IEVar n)
+ 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
- n_mod = moduleName (nameModule n)
+ all_used avail_occs = all (`elem` map nameOccName ns) avail_occs
+ doc = text "Compute minimal imports from" <+> ppr n
+ n_mod = nameModuleName n
\end{code}
dodgyImportWarn mod 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)]
+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
+ 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)
dupDeclErr (n:ns)
= vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr n),