%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[RnNames]{Extracting imported and top-level names in scope}
\begin{code}
-#include "HsVersions.h"
-
module RnNames (
- getGlobalNames,
- SYN_IE(GlobalNameInfo)
+ rnImports, importsFromLocalDecls,
+ reportUnusedNames, reportDeprecations,
+ mkModDeps, exportsToAvails, exportsFromAvail
) where
-import PreludeGlaST ( SYN_IE(MutableVar) )
-
-IMP_Ubiq()
-
-import HsSyn
-import RdrHsSyn
-import RnHsSyn
+#include "HsVersions.h"
-import RnMonad
-import RnIfaces ( IfaceCache, cachedIface, cachedDecl, CachingResult(..) )
-import RnUtils ( SYN_IE(RnEnv), emptyRnEnv, initRnEnv, extendGlobalRnEnv,
- lubExportFlag, qualNameErr, dupNamesErr, pprRnEnv
+import CmdLineOpts ( DynFlag(..) )
+import HsSyn ( IE(..), ieName, ImportDecl(..), LImportDecl,
+ ForeignDecl(..), HsGroup(..), HsBindGroup(..),
+ Sig(..), collectGroupBinders, tyClDeclNames
)
-import ParseUtils ( ParsedIface(..), RdrIfaceDecl(..), ExportsMap(..), RdrIfaceInst )
-
-
-import Bag ( emptyBag, unitBag, consBag, snocBag, unionBags,
- unionManyBags, mapBag, foldBag, filterBag, listToBag, bagToList )
-import CmdLineOpts ( opt_NoImplicitPrelude, opt_CompilingGhcInternals )
-import ErrUtils ( SYN_IE(Error), SYN_IE(Warning), addErrLoc, addShortErrLocLine, addShortWarnLocLine )
-import FiniteMap ( emptyFM, addToFM, addListToFM, lookupFM, fmToList, eltsFM, delListFromFM, keysFM{-ToDo:rm-}, FiniteMap )
-import Id ( GenId )
-import Maybes ( maybeToBool, catMaybes, MaybeErr(..) )
-import Name ( RdrName(..), Name, isQual, mkTopLevName, mkWiredInName, origName,
- nameOf, qualToOrigName, mkImportedName,
- nameExportFlag, nameImportFlag,
- getLocalName, getSrcLoc, getImpLocs,
- moduleNamePair, pprNonSym,
- isLexCon, isLexSpecialSym, ExportFlag(..), OrigName(..)
+import RnEnv
+import IfaceEnv ( lookupOrig, newGlobalBinder )
+import LoadIface ( loadSrcInterface )
+import TcRnMonad
+
+import FiniteMap
+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 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 PrelInfo ( SYN_IE(BuiltinNames), SYN_IE(BuiltinKeys) )
-import PrelMods ( pRELUDE, gHC_BUILTINS, modulesWithBuiltins )
-import Pretty
-import SrcLoc ( SrcLoc, mkBuiltinSrcLoc )
-import TyCon ( tyConDataCons )
-import UniqFM ( emptyUFM, addListToUFM_C, lookupUFM )
-import UniqSupply ( splitUniqSupply )
-import Util ( isIn, assoc, cmpPString, sortLt, removeDups,
- equivClasses, panic, assertPanic, pprPanic{-ToDo:rm-}, pprTrace{-ToDo:rm-}
- )
-import PprStyle --ToDo:rm
+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 ( isNothing, catMaybes, mapCatMaybes, seqMaybe, orElse )
+import SrcLoc ( noSrcLoc, Located(..), mkGeneralSrcSpan,
+ unLoc, noLoc, srcLocSpan, combineSrcSpans, SrcSpan )
+import BasicTypes ( DeprecTxt )
+import ListSetOps ( removeDups )
+import Util ( sortLe, notNull, isSingleton )
+import List ( partition )
+import IO ( openFile, IOMode(..) )
\end{code}
-\begin{code}
-type GlobalNameInfo = (BuiltinNames,
- BuiltinKeys,
- Name -> ExportFlag, -- export flag
- Name -> [RdrName]) -- occurrence names
- -- NB: both of the functions are in a *knot* and
- -- must be tugged on oh-so-gently...
-
-type RnM_Info s r = RnMonad GlobalNameInfo s r
-
-getGlobalNames ::
- IfaceCache
- -> GlobalNameInfo
- -> UniqSupply
- -> RdrNameHsModule
- -> IO (RnEnv,
- [Module], -- directly imported modules
- Bag (Module,RnName), -- unqualified imports from module
- Bag RenamedFixityDecl, -- imported fixity decls
- Bag Error,
- Bag Warning)
-
-getGlobalNames iface_cache info us
- (HsModule mod _ _ imports _ ty_decls _ cls_decls _ _ _ binds _ _)
- = let
- (us1, us2) = splitUniqSupply us
- in
- case initRn True mod emptyRnEnv us1
- (setExtraRn info $
- getSourceNames ty_decls cls_decls binds)
- of { ((src_vals, src_tcs), src_errs, src_warns) ->
-
- doImportDecls iface_cache info us2 imports >>=
- \ (imp_vals, imp_tcs, imp_mods, unqual_imps, imp_fixes, imp_errs, imp_warns) ->
- let
- unqual_vals = map (\rn -> (Unqual (getLocalName rn), rn)) (bagToList src_vals)
- unqual_tcs = map (\rn -> (Unqual (getLocalName rn), rn)) (bagToList src_tcs)
- (src_env, src_dups) = extendGlobalRnEnv initRnEnv unqual_vals unqual_tcs
- (all_env, imp_dups) = extendGlobalRnEnv src_env (bagToList imp_vals) (bagToList imp_tcs)
+%************************************************************************
+%* *
+ rnImports
+%* *
+%************************************************************************
- -- remove dups of the same imported thing
- diff_imp_dups = filterBag diff_orig imp_dups
- diff_orig (_,rn1,rn2) = origName "diff_orig" rn1 /= origName "diff_orig" rn2
+\begin{code}
+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
+ 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
+ ; let
+ (imp_gbl_envs, imp_avails) = unzip (stuff1 ++ stuff2)
+ gbl_env :: GlobalRdrEnv
+ gbl_env = foldr plusGlobalRdrEnv emptyGlobalRdrEnv imp_gbl_envs
+
+ all_avails :: ImportAvails
+ all_avails = foldr plusImportAvails emptyImportAvails imp_avails
+
+ -- ALL DONE
+ ; return (gbl_env, all_avails) }
+ where
+ -- 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 implicit_prelude
+ | this_mod == pRELUDE
+ || explicit_prelude_import
+ || not implicit_prelude
+ = []
+
+ | otherwise = [preludeImportDecl]
+
+ explicit_prelude_import
+ = 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 :: Module
+ -> LImportDecl RdrName
+ -> RnM (GlobalRdrEnv, ImportAvails)
- all_dups = bagToList (src_dups `unionBags` diff_imp_dups)
- dup_errs = map dup_err (equivClasses cmp_rdr all_dups)
- cmp_rdr (rdr1,_,_) (rdr2,_,_) = cmp rdr1 rdr2
- dup_err ((rdr,rn1,rn2):rest) = globalDupNamesErr rdr (rn1:rn2: [rn|(_,_,rn)<-rest])
+importsFromImportDecl this_mod
+ (L loc (ImportDecl loc_imp_mod_name want_boot qual_only as_mod imp_details))
+ =
+ setSrcSpan loc $
- all_errs = src_errs `unionBags` imp_errs `unionBags` listToBag dup_errs
- all_warns = src_warns `unionBags` imp_warns
+ -- If there's an error in loadInterface, (e.g. interface
+ -- file not found) we get lots of spurious errors from 'filterImports'
+ let
+ imp_mod_name = unLoc loc_imp_mod_name
+ doc = ppr imp_mod_name <+> ptext SLIT("is directly imported")
in
--- pprTrace "initRnEnv:" (pprRnEnv PprDebug initRnEnv) $
--- pprTrace "src_env:" (pprRnEnv PprDebug src_env) $
--- pprTrace "all_env:" (pprRnEnv PprDebug all_env) $
- return (all_env, imp_mods, unqual_imps, imp_fixes, all_errs, all_warns) }
-\end{code}
+ loadSrcInterface doc imp_mod_name want_boot `thenM` \ iface ->
-*********************************************************
-* *
-\subsection{Top-level source names}
-* *
-*********************************************************
+ -- 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_`
-\begin{code}
-getSourceNames :: -- Collects global *binders* (not uses)
- [RdrNameTyDecl]
- -> [RdrNameClassDecl]
- -> RdrNameHsBinds
- -> RnM_Info s (Bag RnName, -- values
- Bag RnName) -- tycons/classes
-
-getSourceNames ty_decls cls_decls binds
- = mapAndUnzip3Rn getTyDeclNames ty_decls `thenRn` \ (tycon_s, constrs_s, fields_s) ->
- mapAndUnzipRn getClassNames cls_decls `thenRn` \ (cls_s, cls_ops_s) ->
- getTopBindsNames binds `thenRn` \ bind_names ->
- returnRn (unionManyBags constrs_s `unionBags`
- unionManyBags fields_s `unionBags`
- unionManyBags cls_ops_s `unionBags` bind_names,
- listToBag tycon_s `unionBags` listToBag cls_s)
-
---------------
-getTyDeclNames :: RdrNameTyDecl
- -> RnM_Info s (RnName, Bag RnName, Bag RnName) -- tycon, constrs and fields
-
-getTyDeclNames (TyData _ tycon _ condecls _ _ src_loc)
- = --getExtraRn `thenRn` \ ((b_val_names,b_tc_names),b_keys,rec_exp_fn,rec_occ_fn) ->
- --pprTrace "getTyDeclNames:" (ppr PprDebug tycon) $
- --pprTrace "getTDN1:" (ppAboves [ ppCat [ppPStr m, ppPStr n] | ((OrigName m n), _) <- fmToList b_tc_names]) $
-
- newGlobalName src_loc Nothing False{-not val-} tycon `thenRn` \ tycon_name ->
- getConFieldNames (Just (nameExportFlag tycon_name)) emptyBag emptyBag emptyFM
- condecls `thenRn` \ (con_names, field_names) ->
let
- rn_tycon = RnData tycon_name con_names field_names
- rn_constrs = [ RnConstr name tycon_name | name <- con_names]
- rn_fields = [ RnField name tycon_name | name <- field_names]
+ 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
+ -- filter them out up front. This situation only arises if a module
+ -- imports itself, or another module that imported it. (Necessarily,
+ -- this invoves a loop.)
+ --
+ -- Tiresome consequence: if you say
+ -- module A where
+ -- import B( AType )
+ -- type AType = ...
+ --
+ -- module B( AType ) where
+ -- import {-# SOURCE #-} A( AType )
+ --
+ -- then you'll get a 'B does not export AType' message. 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
- returnRn (rn_tycon, listToBag rn_constrs, listToBag rn_fields)
-
-getTyDeclNames (TyNew _ tycon _ [NewConDecl con _ con_loc] _ _ src_loc)
- = newGlobalName src_loc Nothing False{-not val-} tycon `thenRn` \ tycon_name ->
- newGlobalName con_loc (Just (nameExportFlag tycon_name)) True{-val-} con
- `thenRn` \ con_name ->
- returnRn (RnData tycon_name [con_name] [],
- unitBag (RnConstr con_name tycon_name),
- emptyBag)
-
-getTyDeclNames (TySynonym tycon _ _ src_loc)
- = newGlobalName src_loc Nothing False{-not val-} tycon `thenRn` \ tycon_name ->
- returnRn (RnSyn tycon_name, emptyBag, emptyBag)
-
-----------------
-getConFieldNames :: Maybe ExportFlag
- -> Bag Name -> Bag Name
- -> FiniteMap RdrName ()
- -> [RdrNameConDecl]
- -> RnM_Info s ([Name], [Name])
-
-getConFieldNames exp constrs fields have []
- = returnRn (bagToList constrs, bagToList fields)
-
-getConFieldNames exp constrs fields have (ConDecl con _ src_loc : rest)
- = newGlobalName src_loc exp True{-val-} con `thenRn` \ con_name ->
- getConFieldNames exp (constrs `snocBag` con_name) fields have rest
-
-getConFieldNames exp constrs fields have (ConOpDecl _ con _ src_loc : rest)
- = newGlobalName src_loc exp True{-val-} con `thenRn` \ con_name ->
- getConFieldNames exp (constrs `snocBag` con_name) fields have rest
-
-getConFieldNames exp constrs fields have (RecConDecl con fielddecls src_loc : rest)
- = mapRn (addErrRn . dupFieldErr con src_loc) dups `thenRn_`
- newGlobalName src_loc exp True{-val-} con `thenRn` \ con_name ->
- mapRn (newGlobalName src_loc exp True{-val-}) new_fields `thenRn` \ field_names ->
+ -- 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
- all_constrs = constrs `snocBag` con_name
- all_fields = fields `unionBags` listToBag field_names
+ -- 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 }
+
in
- getConFieldNames exp all_constrs all_fields new_have rest
+ -- 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
- (uniq_fields, dups) = removeDups cmp (concat (map fst fielddecls))
- new_fields = filter (not . maybeToBool . lookupFM have) uniq_fields
- new_have = addListToFM have (zip new_fields (repeat ()))
-
--------------
-getClassNames :: RdrNameClassDecl
- -> RnM_Info s (RnName, Bag RnName) -- class and class ops
-
-getClassNames (ClassDecl _ cname _ sigs _ _ src_loc)
- = newGlobalName src_loc Nothing False{-notval-} cname `thenRn` \ class_name ->
- getClassOpNames (Just (nameExportFlag class_name))
- sigs `thenRn` \ op_names ->
- returnRn (RnClass class_name op_names,
- listToBag (map (\ n -> RnClassOp n class_name) op_names))
-
----------------
-getClassOpNames :: Maybe ExportFlag
- -> [RdrNameSig]
- -> RnM_Info s [Name]
-
-getClassOpNames exp [] = returnRn []
-
-getClassOpNames exp (ClassOpSig op _ _ src_loc : sigs)
- = newGlobalName src_loc exp True{-val-} op `thenRn` \ op_name ->
- getClassOpNames exp sigs `thenRn` \ op_names ->
- returnRn (op_name : op_names)
-getClassOpNames exp (_ : sigs)
- = getClassOpNames exp sigs
+ 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}
-*********************************************************
-* *
-\subsection{Bindings}
-* *
-*********************************************************
-\begin{code}
-getTopBindsNames :: RdrNameHsBinds
- -> RnM_Info s (Bag RnName)
-
-getTopBindsNames binds = doBinds binds
-
-doBinds EmptyBinds = returnRn emptyBag
-doBinds (SingleBind bind) = doBind bind
-doBinds (BindWith bind sigs) = doBind bind
-doBinds (ThenBinds binds1 binds2)
- = andRn unionBags (doBinds binds1) (doBinds binds2)
-
-doBind EmptyBind = returnRn emptyBag
-doBind (NonRecBind mbind) = doMBinds mbind
-doBind (RecBind mbind) = doMBinds mbind
-
-doMBinds EmptyMonoBinds = returnRn emptyBag
-doMBinds (PatMonoBind pat grhss_and_binds locn) = doPat locn pat
-doMBinds (FunMonoBind p_name _ _ locn) = doName locn p_name
-doMBinds (AndMonoBinds mbinds1 mbinds2)
- = andRn unionBags (doMBinds mbinds1) (doMBinds mbinds2)
-
-doPats locn pats
- = mapRn (doPat locn) pats `thenRn` \ pats_s ->
- returnRn (unionManyBags pats_s)
-
-doPat locn WildPatIn = returnRn emptyBag
-doPat locn (LitPatIn _) = returnRn emptyBag
-doPat locn (LazyPatIn pat) = doPat locn pat
-doPat locn (VarPatIn var) = doName locn var
-doPat locn (NegPatIn pat) = doPat locn pat
-doPat locn (ParPatIn pat) = doPat locn pat
-doPat locn (ListPatIn pats) = doPats locn pats
-doPat locn (TuplePatIn pats) = doPats locn pats
-doPat locn (ConPatIn name pats) = doPats locn pats
-doPat locn (ConOpPatIn p1 op p2)
- = andRn unionBags (doPat locn p1) (doPat locn p2)
-doPat locn (AsPatIn as_name pat)
- = andRn unionBags (doName locn as_name) (doPat locn pat)
-doPat locn (RecPatIn name fields)
- = mapRn (doField locn) fields `thenRn` \ fields_s ->
- returnRn (unionManyBags fields_s)
-
-doField locn (_, pat, _) = doPat locn pat
-
-doName locn rdr
- = newGlobalName locn Nothing True{-val-} rdr `thenRn` \ name ->
- returnRn (unitBag (RnName name))
-\end{code}
+%************************************************************************
+%* *
+ importsFromLocalDecls
+%* *
+%************************************************************************
-*********************************************************
-* *
-\subsection{Creating a new global name}
-* *
-*********************************************************
+From the top-level declarations of this module produce
+ * the lexical environment
+ * the ImportAvails
+created by its bindings.
+
+Complain about duplicate bindings
\begin{code}
-newGlobalName :: SrcLoc
- -> Maybe ExportFlag
- -> Bool{-True<=>value name,False<=>tycon/class-}
- -> RdrName
- -> RnM_Info s Name
-
-newGlobalName locn maybe_exp is_val_name (Unqual name)
- = getExtraRn `thenRn` \ ((b_val_names,b_tc_names),b_keys,rec_exp_fn,rec_occ_fn) ->
- getModuleRn `thenRn` \ mod ->
- rnGetUnique `thenRn` \ u ->
+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
- orig = OrigName mod name
-
- (uniq, is_toplev)
- = case (lookupFM b_keys orig) of
- Just (key,_) -> (key, True)
- Nothing -> if not opt_CompilingGhcInternals then (u,True) else -- really here just to save gratuitous lookup
- case (lookupFM (if is_val_name then b_val_names else b_tc_names) orig) of
- Nothing -> (u, True)
- Just xx -> (uniqueOf xx, False{-builtin!-})
-
- exp = case maybe_exp of
- Just flag -> flag
- Nothing -> rec_exp_fn n
-
- n = if is_toplev
- then mkTopLevName uniq orig locn exp (rec_occ_fn n) -- NB: two "n"s
- else mkWiredInName uniq orig exp
- in
- returnRn n
+ all_names :: [Name] -- All the defns; no dups eliminated
+ all_names = [name | avail <- avails, name <- availNames avail]
-newGlobalName locn maybe_exp is_val_name rdr@(Qual mod name)
- | opt_CompilingGhcInternals
- -- we are actually defining something that compiler knows about (e.g., Bool)
+ dups :: [[Name]]
+ (_, dups) = removeDups compare all_names
+ in
+ -- Check for duplicate definitions
+ -- 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_`
- = getExtraRn `thenRn` \ ((b_val_names,b_tc_names),b_keys,rec_exp_fn,rec_occ_fn) ->
+ doptM Opt_ImplicitPrelude `thenM` \ implicit_prelude ->
let
- orig = OrigName mod name
-
- (uniq, is_toplev)
- = case (lookupFM b_keys orig) of
- Just (key,_) -> (key, True)
- Nothing -> case (lookupFM (if is_val_name then b_val_names else b_tc_names) orig) of
- Nothing -> (pprPanic "newGlobalName:Qual:uniq:" (ppr PprDebug rdr), True)
- Just xx -> (uniqueOf xx, False{-builtin!-})
-
- exp = case maybe_exp of
- Just flag -> flag
- Nothing -> rec_exp_fn n
-
- n = if is_toplev
- then mkTopLevName uniq orig locn exp (rec_occ_fn n) -- NB: two "n"s
- else mkWiredInName uniq orig exp
+ 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
- returnRn n
-
- | otherwise
- = addErrRn (qualNameErr "name in definition" (rdr, locn)) `thenRn_`
- returnRn (pprPanic "newGlobalName:Qual:" (ppr PprDebug rdr))
+ returnM (gbl_env, imports)
\end{code}
-*********************************************************
-* *
-\subsection{Imported names}
-* *
-*********************************************************
-\begin{code}
-type ImportNameInfo
- = (GlobalNameInfo,
- FiniteMap OrigName RnName, -- values imported so far
- FiniteMap OrigName RnName, -- tycons/classes imported so far
- Name -> (ExportFlag, [SrcLoc])) -- import flag and src locns;
- -- NB: this last field is in a knot
- -- and mustn't be tugged on!
-
-type RnM_IInfo s r = RnMonad ImportNameInfo s r
-
-------------------------------------------------------------------
-doImportDecls ::
- IfaceCache
- -> GlobalNameInfo -- builtin and knot name info
- -> UniqSupply
- -> [RdrNameImportDecl] -- import declarations
- -> IO (Bag (RdrName,RnName), -- imported values in scope
- Bag (RdrName,RnName), -- imported tycons/classes in scope
- [Module], -- directly imported modules
- Bag (Module,RnName), -- unqualified import from module
- Bag RenamedFixityDecl, -- fixity info for imported names
- Bag Error,
- Bag Warning)
-
-doImportDecls iface_cache g_info us src_imps
- = fixIO ( \ ~(_, _, _, _, _, _, rec_imp_stuff) ->
- let
- rec_imp_fm = addListToUFM_C add_stuff emptyUFM (bagToList rec_imp_stuff)
- add_stuff (imp1,locns1) (imp2,locns2) = (lubExportFlag imp1 imp2, locns1 `unionBags` locns2)
-
- rec_imp_fn :: Name -> (ExportFlag, [SrcLoc])
- rec_imp_fn n = case lookupUFM rec_imp_fm n of
- Nothing -> panic "RnNames:rec_imp_fn"
- Just (flag, locns) -> (flag, bagToList locns)
-
- i_info = (g_info, emptyFM, emptyFM, rec_imp_fn)
- in
- -- cache the imported modules
- -- this ensures that all directly imported modules
- -- will have their original name iface in scope
- -- pprTrace "doImportDecls:" (ppCat (map ppPStr imp_mods)) $
- accumulate (map (cachedIface iface_cache False SLIT("doImportDecls")) imp_mods) >>
-
- -- process the imports
- doImports iface_cache i_info us all_imps
-
- ) >>= \ (vals, tcs, unquals, fixes, errs, warns, _) ->
-
- return (vals, tcs, imp_mods, unquals, fixes,
- imp_errs `unionBags` errs,
- imp_warns `unionBags` warns)
- where
- all_imps = implicit_prel ++ src_imps
--- all_imps = implicit_qprel ++ the_imps
+%*********************************************************
+%* *
+\subsection{Getting binders out of a declaration}
+%* *
+%*********************************************************
- explicit_prelude_imp
- = not (null [ () | (ImportDecl mod qual _ _ _) <- src_imps, mod == pRELUDE ])
+@getLocalDeclBinders@ returns the names for an @HsDecl@. It's
+used for source code.
- implicit_prel | opt_NoImplicitPrelude = []
- | explicit_prelude_imp = [ImportDecl pRELUDE True Nothing Nothing prel_loc]
- | otherwise = [ImportDecl pRELUDE False Nothing Nothing prel_loc]
+ *** See "THE NAMING STORY" in HsDecls ****
- prel_loc = mkBuiltinSrcLoc
+\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.
+
+ 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 ->
- (uniq_imps, imp_dups) = removeDups cmp_mod all_imps
- cmp_mod (ImportDecl m1 _ _ _ _) (ImportDecl m2 _ _ _ _) = cmpPString m1 m2
+ returnM (tc_avails ++ map Avail names)
+ where
+ 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}
- qprel_imps = [ imp | imp@(ImportDecl mod True Nothing _ _) <- src_imps,
- mod == pRELUDE ]
- qual_mods = [ (qual_name mod as_mod, imp) | imp@(ImportDecl mod True as_mod _ _) <- src_imps ]
- qual_name mod (Just as_mod) = as_mod
- qual_name mod Nothing = mod
+%************************************************************************
+%* *
+\subsection{Filtering imports}
+%* *
+%************************************************************************
- (_, qual_dups) = removeDups cmp_qual qual_mods
- bad_qual_dups = filter (not . all_same_mod) qual_dups
+@filterImports@ takes the @ExportEnv@ telling what the imported module makes
+available, and filters it through the import spec (if any).
- cmp_qual (q1,_) (q2,_) = cmpPString q1 q2
- all_same_mod ((q,ImportDecl mod _ _ _ _):rest)
- = all has_same_mod rest
- where
- has_same_mod (_,ImportDecl mod2 _ _ _ _) = mod == mod2
-
- imp_mods = [ mod | ImportDecl mod _ _ _ _ <- uniq_imps ]
-
- imp_warns = listToBag (map dupImportWarn imp_dups)
- `unionBags`
- listToBag (map qualPreludeImportWarn qprel_imps)
-
- imp_errs = listToBag (map dupQualImportErr bad_qual_dups)
-
------------------------
-doImports :: IfaceCache
- -> ImportNameInfo
- -> UniqSupply
- -> [RdrNameImportDecl] -- import declarations
- -> IO (Bag (RdrName,RnName), -- imported values in scope
- Bag (RdrName,RnName), -- imported tycons/classes in scope
- Bag (Module, RnName), -- unqualified import from module
- Bag RenamedFixityDecl, -- fixity info for imported names
- Bag Error,
- Bag Warning,
- Bag (RnName,(ExportFlag,Bag SrcLoc))) -- import flags and src locs
-
-doImports iface_cache i_info us []
- = return (emptyBag, emptyBag, emptyBag, emptyBag, emptyBag, emptyBag, emptyBag)
-
-doImports iface_cache i_info@(g_info,done_vals,done_tcs,rec_imp_fn) us (imp:imps)
- = let
- (us1, us2) = splitUniqSupply us
+\begin{code}
+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.
+
+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 iface imp_spec (Just (want_hiding, import_items)) all_names
+ = mappM (addLocM get_item) import_items `thenM` \ gres_s ->
+ let
+ gres = concat gres_s
+ specified_names = mkNameSet (map gre_name gres)
in
- doImport iface_cache i_info us1 imp
- >>= \ (vals1, tcs1, unquals1, fixes1, errs1, warns1, imps1) ->
+ if not want_hiding then
+ return (specified_names, mkGlobalRdrEnv gres)
+ else
let
- ext_vals = foldl add_new_one done_vals (bagToList vals1)
- ext_tcs = foldl add_new_one done_tcs (bagToList tcs1)
+ keep n = not (n `elemNameSet` specified_names)
+ pruned_avails = filterNameSet keep all_names
in
- doImports iface_cache (g_info,ext_vals,ext_tcs,rec_imp_fn) us2 imps
- >>= \ (vals2, tcs2, unquals2, fixes2, errs2, warns2, imps2) ->
- return (vals1 `unionBags` vals2,
- tcs1 `unionBags` tcs2,
- unquals1 `unionBags` unquals2,
- fixes1 `unionBags` fixes2,
- errs1 `unionBags` errs2,
- warns1 `unionBags` warns2,
- imps1 `unionBags` imps2)
- where
- add_new_one :: FiniteMap OrigName RnName -- ones done so far
- -> (dont_care, RnName)
- -> FiniteMap OrigName RnName -- extended
-
- add_new_one fm (_, rn)
- = let
- orig = origName "add_new_one" rn
- in
- case (lookupFM fm orig) of
- Just _ -> fm -- already there: no change
- Nothing -> addToFM fm orig rn
-
-----------------------
-doImport :: IfaceCache
- -> ImportNameInfo
- -> UniqSupply
- -> RdrNameImportDecl
- -> IO (Bag (RdrName,RnName), -- values
- Bag (RdrName,RnName), -- tycons/classes
- Bag (Module,RnName), -- unqual imports
- Bag RenamedFixityDecl,
- Bag Error,
- Bag Warning,
- Bag (RnName,(ExportFlag,Bag SrcLoc))) -- import flags and src locs
-
-doImport iface_cache info us (ImportDecl mod qual maybe_as maybe_spec src_loc)
- = --let
- -- (b_vals, b_tcs, maybe_spec')
- -- = (emptyBag, emptyBag, maybe_spec)
- --in
- --pprTrace "doImport:" (ppPStr mod) $
- cachedIface iface_cache False SLIT("doImport") mod >>= \ maybe_iface ->
- return (maybe_iface, \ iface -> getOrigIEs iface maybe_spec)
- >>= \ (maybe_iface, do_ies) ->
-
- case maybe_iface of
- Failed err ->
- return (emptyBag, emptyBag, emptyBag, emptyBag,
- unitBag err, emptyBag, emptyBag)
- Succeeded iface ->
- let
- (ies, chk_ies, get_errs) = do_ies iface
- in
- doOrigIEs iface_cache info mod src_loc us ies
- >>= \ (ie_vals, ie_tcs, imp_flags, errs, warns) ->
- accumulate (map (checkOrigIE iface_cache) chk_ies)
- >>= \ chk_errs_warns ->
- let
- fold_ies = foldBag unionBags pair_occ emptyBag
-
- final_vals = {-OLD:mapBag fst_occ b_vals `unionBags`-} fold_ies ie_vals
- final_tcs = {-OLD:mapBag fst_occ b_tcs `unionBags`-} fold_ies ie_tcs
- final_vals_list = bagToList final_vals
- in
- accumulate (map (getFixityDecl iface_cache . snd) final_vals_list)
- >>= \ fix_maybes_errs ->
- let
- (chk_errs, chk_warns) = unzip chk_errs_warns
- (fix_maybes, fix_errs) = unzip fix_maybes_errs
-
- unquals = if qual{-ified import-}
- then emptyBag
- else mapBag pair_as (ie_vals `unionBags` ie_tcs)
-
- final_fixes = listToBag (catMaybes fix_maybes)
-
- final_errs = mapBag (\ err -> err mod src_loc) (unionManyBags (get_errs:chk_errs))
- `unionBags` errs `unionBags` unionManyBags fix_errs
- final_warns = mapBag (\ warn -> warn mod src_loc) (unionManyBags chk_warns)
- `unionBags` warns
- imp_stuff = mapBag (\ (n,imp) -> (n,(imp,unitBag src_loc))) imp_flags
- in
- return (final_vals, final_tcs, unquals, final_fixes,
- final_errs, final_warns, imp_stuff)
- where
- as_mod :: Module
- as_mod = case maybe_as of {Nothing -> mod; Just as_this -> as_this}
-
- mk_occ :: FAST_STRING -> RdrName
- mk_occ str = if qual then Qual as_mod str else Unqual str
-
- fst_occ :: (FAST_STRING, RnName) -> (RdrName, RnName)
- fst_occ (str, rn) = (mk_occ str, rn)
-
- pair_occ :: RnName -> Bag (RdrName, RnName)
- pair_occ rn
- = let
- str = getLocalName rn
- qual_bag = unitBag (Qual as_mod str, rn)
- in
- if qual
- then qual_bag
- else qual_bag -- the qualified name is *also* visible
- `snocBag` (Unqual str, rn)
-
-
- pair_as :: RnName -> (Module, RnName)
- pair_as rn = (as_mod, rn)
-
------------------------------
-{-
-getBuiltins :: ImportNameInfo
- -> Module
- -> Maybe (Bool, [RdrNameIE])
- -> (Bag (FAST_STRING, RnName),
- Bag (FAST_STRING, RnName),
- Maybe (Bool, [RdrNameIE]) -- return IEs that had no effect
- )
-
-getBuiltins _ modname maybe_spec
--- | modname `notElem` modulesWithBuiltins
- = (emptyBag, emptyBag, maybe_spec)
-
-getBuiltins (((b_val_names,b_tc_names),_,_,_),_,_,_) modname maybe_spec
- = case maybe_spec of
- Nothing -> (all_vals, all_tcs, Nothing)
-
- Just (True, ies) -> -- hiding does not work for builtin names
- trace "NOTE: `import Prelude hiding ...' does not hide built-in names" $
- (all_vals, all_tcs, maybe_spec)
-
- Just (False, ies) -> let
- (vals,tcs,ies_left) = do_builtin ies
- in
- (vals, tcs, Just (False, ies_left))
+ return (pruned_avails, mkGenericRdrEnv imp_spec pruned_avails)
+
where
- all_vals = do_all_builtin (fmToList b_val_names)
- all_tcs = do_all_builtin (fmToList b_tc_names)
-
- do_all_builtin [] = emptyBag
- do_all_builtin (((OrigName mod str),rn):rest)
- = --pprTrace "do_all_builtin:" (ppCat [ppPStr modname, ppPStr mod, ppPStr str]) $
- (if mod == modname then consBag (str, rn) else id) (do_all_builtin rest)
-
- do_builtin [] = (emptyBag,emptyBag,[])
- do_builtin (ie:ies)
- = let
- (str, orig)
- = case (ie_name ie) of
- Unqual s -> (s, OrigName modname s)
- Qual m s -> pprTrace "do_builtin:surprising qual!" (ppCat [ppPStr m, ppPStr s]) $
- (s, OrigName modname s)
- in
- case (lookupFM b_tc_names orig) of -- NB: we favour the tycon/class FM...
- Just rn -> case (ie,rn) of
- (IEThingAbs _, WiredInTyCon tc)
- -> (vals, (str, rn) `consBag` tcs, ies_left)
- (IEThingAll _, WiredInTyCon tc)
- -> (listToBag (map (\ id -> (getLocalName id, WiredInId id))
- (tyConDataCons tc))
- `unionBags` vals,
- (str,rn) `consBag` tcs, ies_left)
- (IEThingWith _ _, WiredInTyCon tc) -- No checking of With...
- -> (listToBag (map (\ id -> (nameOf (origName "IEThingWith" id), WiredInId id))
- (tyConDataCons tc))
- `unionBags` vals,
- (str,rn) `consBag` tcs, ies_left)
- _ -> panic "importing builtin names (1)"
-
- Nothing ->
- case (lookupFM b_val_names orig) of
- Nothing -> (vals, tcs, ie:ies_left)
- Just rn -> case (ie,rn) of
- (IEVar _, WiredInId _)
- -> ((str, rn) `consBag` vals, tcs, ies_left)
- _ -> panic "importing builtin names (2)"
+ 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.
+
+ sub_env :: NameEnv [Name]
+ sub_env = mkSubNameEnv all_names
+
+ bale_out item = addErr (badImportItemErr iface imp_spec item) `thenM_`
+ returnM []
+
+ 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
+ [] -> 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, or even both
+ = case concat [check_item item, check_item (IEVar data_n)] of
+ [] -> bale_out item
+ names -> succeed_with True names
where
- (vals, tcs, ies_left) = do_builtin ies
--}
+ data_n = setRdrNameSpace n srcDataName
+
+ get_item item
+ = case check_item item of
+ [] -> 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}
--------------------------
-getOrigIEs :: ParsedIface
- -> Maybe (Bool, [RdrNameIE]) -- "hiding" or not, blah, blah, blah
- -> ([IE OrigName],
- [(IE OrigName, ExportFlag)],
- Bag (Module -> SrcLoc -> Error))
-getOrigIEs (ParsedIface _ _ _ _ _ _ exps _ _ _ _ _ _) Nothing -- import all
- = (map mkAllIE (eltsFM exps), [], emptyBag)
+%************************************************************************
+%* *
+\subsection{Export list processing}
+%* *
+%************************************************************************
-getOrigIEs (ParsedIface _ _ _ _ _ _ exps _ _ _ _ _ _) (Just (True, ies)) -- import hiding
- = (map mkAllIE (eltsFM exps_left), found_ies, errs)
- where
- (found_ies, errs) = lookupIEs exps ies
- exps_left = delListFromFM exps (map (getLocalName.ie_name.fst) found_ies)
+Processing the export list.
-getOrigIEs (ParsedIface _ _ _ _ _ _ exps _ _ _ _ _ _) (Just (False, ies)) -- import these
- = (map fst found_ies, found_ies, errs)
- where
- (found_ies, errs) = lookupIEs exps ies
-
-------------------------------------------------
-mkAllIE :: (OrigName, ExportFlag) -> IE OrigName
-
-mkAllIE (orig,ExportAbs)
- = --ASSERT(isLexCon (nameOf orig))
- -- the ASSERT is correct, but it is too easy to
- -- trigger when writing .hi files by hand (e.g.
- -- when hackily breaking a module loop)
- IEThingAbs orig
-mkAllIE (orig, ExportAll)
- | isLexCon name_orig || isLexSpecialSym name_orig
- = IEThingAll orig
- | otherwise
- = IEVar orig
- where
- name_orig = nameOf orig
+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).
-------------
-lookupIEs :: ExportsMap
- -> [RdrNameIE]
- -> ([(IE OrigName, ExportFlag)], -- IEs we found, orig-ified
- Bag (Module -> SrcLoc -> Error))
+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...
-lookupIEs exps ies
- = foldr go ([], emptyBag) ies
+\begin{code}
+type ExportAccum -- The type of the accumulating parameter of
+ -- the main worker function in exportsFromAvail
+ = ([Module], -- 'module M's seen so far
+ ExportOccMap, -- Tracks exported occurrence names
+ NameSet) -- The accumulated exported stuff
+emptyExportAccum = ([], emptyOccEnv, emptyNameSet)
+
+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 :: 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 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
- go ie (already, errs)
- = let
- str = case (ie_name ie) of
- Unqual s -> s
- Qual m s -> s
- in
- case (lookupFM exps str) of
- Nothing ->
- (already, unknownImpSpecErr ie `consBag` errs)
- Just (orig, flag) ->
- ((orig_ie orig ie, flag) : already,
- adderr_if (seen_ie orig already) (duplicateImpSpecErr ie) errs)
-
- orig_ie orig (IEVar n) = IEVar orig
- orig_ie orig (IEThingAbs n) = IEThingAbs orig
- orig_ie orig (IEThingAll n) = IEThingAll orig
- orig_ie orig (IEThingWith n ns) = IEThingWith orig (map re_orig ns)
- where
- (OrigName mod _) = orig
- re_orig (Unqual s) = OrigName mod s
-
- seen_ie orig seen_ies = any (\ (ie,_) -> orig == ie_name ie) seen_ies
+ 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 :: ExportAccum -> IE RdrName -> RnM ExportAccum
+ exports_from_item acc@(mods, occs, exports) ie@(IEModuleContents mod)
+ | mod `elem` mods -- Duplicate export of M
+ = do { warn_dup_exports <- doptM Opt_WarnDuplicateExports ;
+ warnIf warn_dup_exports (dupModuleExport mod) ;
+ returnM acc }
+
+ | otherwise
+ = 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
+ env = mkOccEnv [(nameOccName s, s) | s <- subNames subs n]
+ mb_names = map (lookupOccEnv env . rdrNameOcc) rdrs
---------------------------------------------
-doOrigIEs iface_cache info mod src_loc us []
- = return (emptyBag,emptyBag,emptyBag,emptyBag,emptyBag)
+subNames :: NameEnv [Name] -> Name -> [Name]
+subNames env n = lookupNameEnv env n `orElse` []
-doOrigIEs iface_cache info mod src_loc us (ie:ies)
- = let
- (us1, us2) = splitUniqSupply us
- in
- doOrigIE iface_cache info mod src_loc us1 ie
- >>= \ (vals1, tcs1, imps1, errs1, warns1) ->
- doOrigIEs iface_cache info mod src_loc us2 ies
- >>= \ (vals2, tcs2, imps2, errs2, warns2) ->
- return (vals1 `unionBags` vals2,
- tcs1 `unionBags` tcs2,
- imps1 `unionBags` imps2,
- errs1 `unionBags` errs2,
- warns1 `unionBags` warns2)
-
-----------------------
-doOrigIE :: IfaceCache
- -> ImportNameInfo
- -> Module
- -> SrcLoc
- -> UniqSupply
- -> IE OrigName
- -> IO (Bag RnName, -- values
- Bag RnName, -- tycons/classes
- Bag (RnName,ExportFlag), -- import flags
- Bag Error,
- Bag Warning)
-
-doOrigIE iface_cache info mod src_loc us ie
- = with_decl iface_cache (ie_name ie)
- avoided_fn
- (\ err -> (emptyBag, emptyBag, emptyBag, unitBag err, emptyBag))
- (\ decl -> case initRn True mod emptyRnEnv us
- (setExtraRn info $
- pushSrcLocRn src_loc $
- getIfaceDeclNames ie decl)
- of
- ((vals, tcs, imps), errs, warns) -> (vals, tcs, imps, errs, warns))
+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
- avoided_fn Nothing -- the thing should be in the source
- = (emptyBag, emptyBag, emptyBag, emptyBag, emptyBag)
- avoided_fn (Just (Left rn@(WiredInId _))) -- a builtin value brought into scope
- = (unitBag rn, emptyBag, emptyBag, emptyBag, emptyBag)
- avoided_fn (Just (Right rn@(WiredInTyCon tc)))
- -- a builtin tc brought into scope; we also must bring its
- -- data constructors into scope
- = --pprTrace "avoided:Right:" (ppr PprDebug rn) $
- (listToBag [WiredInId dc | dc <- tyConDataCons tc], unitBag rn, emptyBag, emptyBag, emptyBag)
-
--------------------------
-checkOrigIE :: IfaceCache
- -> (IE OrigName, ExportFlag)
- -> IO (Bag (Module -> SrcLoc -> Error), Bag (Module -> SrcLoc -> Warning))
-
-checkOrigIE iface_cache (IEThingAll n, ExportAbs)
- = with_decl iface_cache n
- (\ _ -> (emptyBag, emptyBag))
- (\ err -> (unitBag (\ mod locn -> err), emptyBag))
- (\ decl -> case decl of
- TypeSig _ _ _ -> (emptyBag, unitBag (allWhenSynImpSpecWarn n))
- other -> (unitBag (allWhenAbsImpSpecErr n), emptyBag))
-
-checkOrigIE iface_cache (IEThingWith n ns, ExportAbs)
- = return (unitBag (withWhenAbsImpSpecErr n), emptyBag)
-
-checkOrigIE iface_cache (IEThingWith n ns, ExportAll)
- = with_decl iface_cache n
- (\ _ -> (emptyBag, emptyBag))
- (\ err -> (unitBag (\ mod locn -> err), emptyBag))
- (\ decl -> case decl of
- NewTypeSig _ con _ _ -> (check_with "constructors" [con] ns, emptyBag)
- DataSig _ cons fields _ _ -> (check_with "constructors (and fields)" (cons++fields) ns, emptyBag)
- ClassSig _ ops _ _ -> (check_with "class ops" ops ns, emptyBag))
+ 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_with str has origs
- | sortLt (<) (map getLocalName has) == sortLt (<) (map nameOf origs)
- = emptyBag
- | otherwise
- = unitBag (withImpSpecErr str n has origs)
-
-checkOrigIE iface_cache other
- = return (emptyBag, emptyBag)
-
------------------------
-with_decl :: IfaceCache
- -> OrigName
- -> (Maybe (Either RnName RnName) -> something) -- if avoided..
- -> (Error -> something) -- if an error...
- -> (RdrIfaceDecl -> something) -- if OK...
- -> IO something
-
-with_decl iface_cache n do_avoid do_err do_decl
- = cachedDecl iface_cache (isLexCon n_name || isLexSpecialSym n_name) n >>= \ maybe_decl ->
- case maybe_decl of
- CachingAvoided info -> return (do_avoid info)
- CachingFail err -> return (do_err err)
- CachingHit decl -> return (do_decl decl)
- where
- n_name = nameOf n
-
--------------
-getFixityDecl :: IfaceCache
- -> RnName
- -> IO (Maybe RenamedFixityDecl, Bag Error)
-
-getFixityDecl iface_cache rn
- = let
- (OrigName mod str) = origName "getFixityDecl" rn
-
- succeeded infx i = return (Just (infx rn i), emptyBag)
- in
- cachedIface iface_cache True str mod >>= \ maybe_iface ->
- case maybe_iface of
- Failed err ->
- return (Nothing, unitBag err)
- Succeeded (ParsedIface _ _ _ _ _ _ _ _ fixes _ _ _ _) ->
- case lookupFM fixes str of
- Nothing -> return (Nothing, emptyBag)
- Just (InfixL _ i) -> succeeded InfixL i
- Just (InfixR _ i) -> succeeded InfixR i
- Just (InfixN _ i) -> succeeded InfixN i
-
-ie_name (IEVar n) = n
-ie_name (IEThingAbs n) = n
-ie_name (IEThingAll n) = n
-ie_name (IEThingWith n _) = n
-
-adderr_if True err errs = err `consBag` errs
-adderr_if False err errs = errs
+ 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
\end{code}
-*********************************************************
-* *
-\subsection{Actually creating the imported names}
-* *
-*********************************************************
+%*********************************************************
+%* *
+ Deprecations
+%* *
+%*********************************************************
\begin{code}
-getIfaceDeclNames :: IE OrigName -> RdrIfaceDecl
- -> RnM_IInfo s (Bag RnName, -- values
- Bag RnName, -- tycons/classes
- Bag (RnName,ExportFlag)) -- import flags
-
-getIfaceDeclNames ie (ValSig val src_loc _)
- = newImportedName False src_loc Nothing Nothing val `thenRn` \ val_name ->
- returnRn (unitBag (RnName val_name),
- emptyBag,
- unitBag (RnName val_name, ExportAll))
-
-getIfaceDeclNames ie (TypeSig tycon src_loc _)
- = newImportedName True src_loc Nothing Nothing tycon `thenRn` \ tycon_name ->
- returnRn (emptyBag,
- unitBag (RnSyn tycon_name),
- unitBag (RnSyn tycon_name, ExportAll))
-
-getIfaceDeclNames ie (NewTypeSig tycon con src_loc _)
- = newImportedName True src_loc Nothing Nothing tycon `thenRn` \ tycon_name ->
- newImportedName False src_loc (Just (nameExportFlag tycon_name))
- (Just (nameImportFlag tycon_name))
- con `thenRn` \ con_name ->
- returnRn (if imp_all (imp_flag ie) then
- unitBag (RnConstr con_name tycon_name)
- else
- emptyBag,
- unitBag (RnData tycon_name [con_name] []),
- unitBag (RnData tycon_name [con_name] [], imp_flag ie))
-
-getIfaceDeclNames ie (DataSig tycon cons fields src_loc _)
- = newImportedName True src_loc Nothing Nothing tycon `thenRn` \ tycon_name ->
- let
- map_me = mapRn (newImportedName False src_loc
- (Just (nameExportFlag tycon_name))
- (Just (nameImportFlag tycon_name)))
- in
- map_me cons `thenRn` \ con_names ->
- map_me fields `thenRn` \ field_names ->
- let
- rn_tycon = RnData tycon_name con_names field_names
- rn_constrs = [ RnConstr name tycon_name | name <- con_names ]
- rn_fields = [ RnField name tycon_name | name <- field_names ]
- in
- returnRn (if imp_all (imp_flag ie) then
- listToBag rn_constrs `unionBags` listToBag rn_fields
- else
- emptyBag,
- unitBag rn_tycon,
- unitBag (rn_tycon, imp_flag ie))
-
-getIfaceDeclNames ie (ClassSig cls ops src_loc _)
- = newImportedName True src_loc Nothing Nothing cls `thenRn` \ cls_name ->
- mapRn (newImportedName False src_loc (Just (nameExportFlag cls_name))
- (Just (nameImportFlag cls_name)))
- ops `thenRn` \ op_names ->
- returnRn (if imp_all (imp_flag ie) then
- listToBag (map (\ n -> RnClassOp n cls_name) op_names)
- else
- emptyBag,
- unitBag (RnClass cls_name op_names),
- unitBag (RnClass cls_name op_names, imp_flag ie))
-
-
-imp_all ExportAll = True
-imp_all _ = False
-
-imp_flag (IEThingAbs _) = ExportAbs
-imp_flag (IEThingAll _) = ExportAll
-imp_flag (IEThingWith _ _) = ExportAll
+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}
-*********************************************************
-* *
-\subsection{Creating a new imported name}
-* *
-*********************************************************
+%*********************************************************
+%* *
+ Unused names
+%* *
+%*********************************************************
\begin{code}
-newImportedName :: Bool -- True => tycon or class
- -> SrcLoc
- -> Maybe ExportFlag -- maybe export flag
- -> Maybe ExportFlag -- maybe import flag
- -> RdrName -- orig name
- -> RnM_IInfo s Name
-
-newImportedName tycon_or_class locn maybe_exp maybe_imp rdr
- = let
- orig = qualToOrigName rdr
- in
- getExtraRn `thenRn` \ ((_,b_keys,rec_exp_fn,rec_occ_fn),done_vals,done_tcs,rec_imp_fn) ->
- case ((if tycon_or_class
- then lookupFM done_tcs
- else lookupFM done_vals) orig) of
-
- Just rn -> returnRn (getName rn)
- Nothing ->
- rnGetUnique `thenRn` \ u ->
- let
- uniq = case lookupFM b_keys orig of
- Nothing -> u
- Just (key,_) -> key
-
- exp = case maybe_exp of
- Just xx -> xx
- Nothing -> rec_exp_fn n
-
- imp = case maybe_imp of
- Just xx -> xx
- Nothing -> imp_flag
-
- (imp_flag, imp_locs) = rec_imp_fn n
-
- n = mkImportedName uniq orig imp locn imp_locs exp (rec_occ_fn n) -- NB: two "n"s
- in
- returnRn n
-\end{code}
-
-\begin{code}
-globalDupNamesErr rdr rns sty
- = ppAboves (message : map pp_dup rns)
+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
- message = ppBesides [ppStr "multiple declarations of `", pprNonSym sty rdr, ppStr "'"]
-
- pp_dup rn = addShortErrLocLine (get_loc rn) (\ sty ->
- ppCat [pp_descrip rn, pprNonSym sty rn]) sty
-
- get_loc rn = case getImpLocs rn of
- [] -> getSrcLoc rn
- locs -> head locs
-
- pp_descrip (RnName _) = ppStr "as a value:"
- pp_descrip (RnSyn _) = ppStr "as a type synonym:"
- pp_descrip (RnData _ _ _) = ppStr "as a data type:"
- pp_descrip (RnConstr _ _) = ppStr "as a data constructor:"
- pp_descrip (RnField _ _) = ppStr "as a record field:"
- pp_descrip (RnClass _ _) = ppStr "as a class:"
- pp_descrip (RnClassOp _ _) = ppStr "as a class method:"
- pp_descrip _ = ppNil
-
-dupImportWarn (ImportDecl m1 _ _ _ locn1 : dup_imps) sty
- = ppAboves (item1 : map dup_item dup_imps)
+ 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
- item1 = addShortWarnLocLine locn1 (\ sty ->
- ppCat [ppStr "multiple imports from module", ppPStr m1]) sty
+ 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}
- dup_item (ImportDecl m _ _ _ locn)
- = addShortWarnLocLine locn (\ sty ->
- ppCat [ppStr "here was another import from module", ppPStr m]) sty
-qualPreludeImportWarn (ImportDecl m _ _ _ locn)
- = addShortWarnLocLine locn (\ sty ->
- ppCat [ppStr "qualified import of prelude module", ppPStr m])
+%************************************************************************
+%* *
+\subsection{Errors}
+%* *
+%************************************************************************
-dupQualImportErr ((q1,ImportDecl _ _ _ _ locn1):dup_quals) sty
- = ppAboves (item1 : map dup_item dup_quals)
+\begin{code}
+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 | mi_boot iface = ptext SLIT("(hi-boot interface)")
+ | otherwise = empty
+
+dodgyImportWarn item = dodgyMsg (ptext SLIT("import")) item
+dodgyExportWarn item = dodgyMsg (ptext SLIT("export")) 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") ]
+
+modExportErr mod
+ = hsep [ ptext SLIT("Unknown module in export list: module"), quotes (ppr mod)]
+
+exportItemErr export_item
+ = 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 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)
+
+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
- item1 = addShortErrLocLine locn1 (\ sty ->
- ppCat [ppStr "multiple imports (from different modules) with same qualified name", ppPStr q1]) sty
-
- dup_item (q,ImportDecl _ _ _ _ locn)
- = addShortErrLocLine locn (\ sty ->
- ppCat [ppStr "here was another import with qualified name", ppPStr q]) sty
-
-unknownImpSpecErr ie imp_mod locn
- = addShortErrLocLine locn (\ sty ->
- ppBesides [ppStr "module ", ppPStr imp_mod, ppStr " does not export `", ppr sty (ie_name ie), ppStr "'"])
-
-duplicateImpSpecErr ie imp_mod locn
- = addShortErrLocLine locn (\ sty ->
- ppBesides [ppStr "`", ppr sty (ie_name ie), ppStr "' already seen in import list"])
-
-allWhenSynImpSpecWarn n imp_mod locn
- = addShortWarnLocLine locn (\ sty ->
- ppBesides [ppStr "type synonym `", ppr sty n, ppStr "' should not be imported with (..)"])
-
-allWhenAbsImpSpecErr n imp_mod locn
- = addShortErrLocLine locn (\ sty ->
- ppBesides [ppStr "module ", ppPStr imp_mod, ppStr " only exports `", ppr sty n, ppStr "' abstractly"])
-
-withWhenAbsImpSpecErr n imp_mod locn
- = addShortErrLocLine locn (\ sty ->
- ppBesides [ppStr "module ", ppPStr imp_mod, ppStr " only exports `", ppr sty n, ppStr "' abstractly"])
-
-withImpSpecErr str n has ns imp_mod locn
- = addErrLoc locn "" (\ sty ->
- ppAboves [ ppBesides [ppStr "inconsistent list of", ppStr str, ppStr "in import list for `", ppr sty n, ppStr "'"],
- ppCat [ppStr " expected:", ppInterleave ppComma (map (ppr sty) has)],
- ppCat [ppStr " found: ", ppInterleave ppComma (map (ppr sty) ns)] ])
-
-dupFieldErr con locn (dup:rest)
- = addShortErrLocLine locn (\ sty ->
- ppBesides [ppStr "record field `", ppr sty dup, ppStr "declared multiple times in `", ppr sty con, ppStr "'"])
+ 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),
+ ptext SLIT("is exported by"), quotes (ppr ie1),
+ ptext SLIT("and"), quotes (ppr ie2)]
+
+dupModuleExport mod
+ = 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}