%
-% (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,
- GlobalNameInfo(..)
+ rnImports, importsFromLocalDecls, exportsFromAvail,
+ reportUnusedNames
) where
-import PreludeGlaST ( MutableVar(..) )
-
-import Ubiq
-
-import HsSyn
-import RdrHsSyn
-import RnHsSyn
+#include "HsVersions.h"
-import RnMonad
-import RnIfaces ( IfaceCache(..), cachedIface, cachedDecl )
-import RnUtils ( RnEnv(..), emptyRnEnv, extendGlobalRnEnv,
- lubExportFlag, qualNameErr, dupNamesErr, negateNameWarn )
-import ParseUtils ( ParsedIface(..), RdrIfaceDecl(..), RdrIfaceInst )
+import {-# SOURCE #-} RnHiFiles ( loadInterface )
+import CmdLineOpts ( DynFlag(..) )
-import Bag ( emptyBag, unitBag, consBag, snocBag, unionBags,
- unionManyBags, mapBag, listToBag, bagToList )
-import CmdLineOpts ( opt_NoImplicitPrelude )
-import ErrUtils ( Error(..), Warning(..), addErrLoc, addShortErrLocLine )
-import FiniteMap ( emptyFM, addListToFM, lookupFM, fmToList, eltsFM, delListFromFM )
-import Id ( GenId )
-import Maybes ( maybeToBool, catMaybes, MaybeErr(..) )
-import Name ( RdrName(..), Name, isQual, mkTopLevName,
- mkImportedName, nameExportFlag, nameImportFlag,
- getLocalName, getSrcLoc, pprNonSym, moduleNamePair,
- isLexCon, isRdrLexCon, ExportFlag(..)
+import HsSyn ( HsDecl(..), IE(..), ieName, ImportDecl(..),
+ ForeignDecl(..), HsGroup(..),
+ collectLocatedHsBinders, tyClDeclNames
+ )
+import RdrHsSyn ( RdrNameIE, RdrNameImportDecl, RdrNameHsDecl )
+import RnEnv
+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, 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 PrelInfo ( BuiltinNames(..), BuiltinKeys(..) )
-import PrelMods ( fromPrelude, pRELUDE )
-import Pretty
-import SrcLoc ( SrcLoc, mkIfaceSrcLoc )
-import TyCon ( tyConDataCons )
-import UniqFM ( emptyUFM, addListToUFM_C, lookupUFM )
-import UniqSupply ( splitUniqSupply )
-import Util ( isIn, assoc, cmpPString, sortLt, removeDups,
- equivClasses, panic, assertPanic )
+import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace,
+ emptyRdrEnv, foldRdrEnv, isQual )
+import Outputable
+import Maybes ( maybeToBool, catMaybes )
+import ListSetOps ( removeDups )
+import Util ( sortLt, notNull )
+import List ( partition )
+import IO ( openFile, IOMode(..) )
\end{code}
-\begin{code}
-type GlobalNameInfo = (BuiltinNames,
- BuiltinKeys,
- Name -> ExportFlag, -- export flag
- Name -> [RdrName]) -- occurence names
-
-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 _ _)
- = 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 = mapBag (\rn -> (Unqual (getLocalName rn), rn)) src_vals
- unqual_tcs = mapBag (\rn -> (Unqual (getLocalName rn), rn)) src_tcs
+%************************************************************************
+%* *
+ rnImports
+%* *
+%************************************************************************
- all_vals = bagToList (unqual_vals `unionBags` imp_vals)
- all_tcs = bagToList (unqual_tcs `unionBags` imp_tcs)
+\begin{code}
+rnImports :: [RdrNameImportDecl]
+ -> TcRn m (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
+ (source, ordinary) = partition is_source_import all_imports
+ is_source_import (ImportDecl _ is_boot _ _ _ _) = is_boot
- (all_env, dups) = extendGlobalRnEnv emptyRnEnv all_vals all_tcs
+ get_imports = importsFromImportDecl (moduleName this_mod)
+ in
+ mappM get_imports ordinary `thenM` \ stuff1 ->
+ mappM get_imports source `thenM` \ stuff2 ->
- dup_errs = map dup_err (equivClasses cmp_rdr (bagToList dups))
- cmp_rdr (rdr1,_,_) (rdr2,_,_) = cmp rdr1 rdr2
- dup_err ((_,rn,rn'):rest) = globalDupNamesErr (rn:rn': [rn|(_,_,rn)<-rest])
+ -- COMBINE RESULTS
+ let
+ (imp_gbl_envs, imp_avails) = unzip (stuff1 ++ stuff2)
+ gbl_env :: GlobalRdrEnv
+ gbl_env = foldr plusGlobalRdrEnv emptyRdrEnv imp_gbl_envs
- all_errs = src_errs `unionBags` imp_errs `unionBags` listToBag dup_errs
- all_warns = src_warns `unionBags` imp_warns
- in
- return (all_env, imp_mods, unqual_imps, imp_fixes, all_errs, all_warns)
- }
+ all_avails :: ImportAvails
+ all_avails = foldr plusImportAvails emptyImportAvails imp_avails
+ in
+ -- ALL DONE
+ returnM (gbl_env, all_avails)
where
- (us1, us2) = splitUniqSupply us
-\end{code}
+ -- 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
+ | moduleName this_mod == pRELUDE_Name
+ || explicit_prelude_import
+ || no_prelude
+ = []
-*********************************************************
-* *
-\subsection{Top-level source names}
-* *
-*********************************************************
+ | otherwise = [preludeImportDecl loc]
+ explicit_prelude_import
+ = notNull [ () | (ImportDecl mod _ _ _ _ _) <- imports,
+ mod == pRELUDE_Name ]
+
+preludeImportDecl loc
+ = ImportDecl pRELUDE_Name
+ False {- Not a boot interface -}
+ False {- Not qualified -}
+ Nothing {- No "as" -}
+ Nothing {- No import list -}
+ loc
+\end{code}
+
\begin{code}
-getSourceNames ::
- [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)
- = newGlobalName src_loc Nothing tycon `thenRn` \ tycon_name ->
- getConFieldNames (Just (nameExportFlag tycon_name)) emptyBag emptyBag emptyFM
- condecls `thenRn` \ (con_names, field_names) ->
+importsFromImportDecl :: ModuleName
+ -> RdrNameImportDecl
+ -> TcRn m (GlobalRdrEnv, ImportAvails)
+
+importsFromImportDecl this_mod_name
+ (ImportDecl imp_mod_name is_boot qual_only as_mod import_spec iloc)
+ = addSrcLoc iloc $
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]
+ doc = ppr imp_mod_name <+> ptext SLIT("is directly imported")
in
- returnRn (rn_tycon, listToBag rn_constrs, listToBag rn_fields)
-getTyDeclNames (TyNew _ tycon _ [NewConDecl con _ con_loc] _ _ src_loc)
- = newGlobalName src_loc Nothing tycon `thenRn` \ tycon_name ->
- newGlobalName con_loc (Just (nameExportFlag tycon_name)) con
- `thenRn` \ con_name ->
- returnRn (RnData tycon_name [con_name] [],
- unitBag (RnConstr con_name tycon_name),
- emptyBag)
+ -- If there's an error in loadInterface, (e.g. interface
+ -- file not found) we get lots of spurious errors from 'filterImports'
+ tryM (loadInterface doc imp_mod_name (ImportByUser is_boot)) `thenM` \ mb_iface ->
-getTyDeclNames (TySynonym tycon _ _ src_loc)
- = newGlobalName src_loc Nothing tycon `thenRn` \ tycon_name ->
- returnRn (RnSyn tycon_name, emptyBag, emptyBag)
+ case mb_iface of {
+ Left exn -> returnM (emptyRdrEnv, emptyImportAvails ) ;
+ Right iface ->
+ 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 ]
+ -- 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.
-getConFieldNames exp constrs fields have []
- = returnRn (bagToList constrs, bagToList fields)
-
-getConFieldNames exp constrs fields have (ConDecl con _ src_loc : rest)
- = newGlobalName src_loc exp con `thenRn` \ con_name ->
- getConFieldNames exp (constrs `snocBag` con_name) fields have rest
+ in
+ -- Complain if we import a deprecated module
+ ifOptM Opt_WarnDeprecations (
+ case deprecs of
+ DeprecAll txt -> addWarn (moduleDeprec imp_mod_name txt)
+ other -> returnM ()
+ ) `thenM_`
-getConFieldNames exp constrs fields have (ConOpDecl _ con _ src_loc : rest)
- = newGlobalName src_loc exp con `thenRn` \ con_name ->
- getConFieldNames exp (constrs `snocBag` con_name) fields have rest
+ -- Filter the imports according to the import list
+ filterImports imp_mod_name is_boot import_spec avails `thenM` \ (filtered_avails, explicits) ->
-getConFieldNames exp constrs fields have (RecConDecl con fielddecls src_loc : rest)
- = mapRn (addErrRn . dupFieldErr con src_loc) dups `thenRn_`
- newGlobalName src_loc exp con `thenRn` \ con_name ->
- mapRn (newGlobalName src_loc exp) new_fields `thenRn` \ field_names ->
let
- all_constrs = constrs `snocBag` con_name
- all_fields = fields `unionBags` listToBag field_names
+ 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
- getConFieldNames exp all_constrs all_fields new_have rest
- 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 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 exp []
- = returnRn []
-getClassOpNames exp (ClassOpSig op _ _ src_loc : sigs)
- = newGlobalName src_loc exp op `thenRn` \ op_name ->
- getClassOpNames exp sigs `thenRn` \ op_names ->
- returnRn (op_name : op_names)
-getClassOpNames exp (_ : sigs)
- = getClassOpNames exp sigs
+ returnM (gbl_env, imports { imp_mods = dir_imp})
+ }
+
+import_all (Just (False, _)) = False -- Imports are spec'd explicitly
+import_all other = True -- Everything is imported
\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 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
- -> RdrName -> RnM_Info s Name
+importsFromLocalDecls :: HsGroup RdrName
+ -> TcRn m (GlobalRdrEnv, ImportAvails)
+importsFromLocalDecls group
+ = getModule `thenM` \ this_mod ->
+ getLocalDeclBinders this_mod group `thenM` \ avails ->
+ -- The avails that are returned don't include the "system" names
+ let
+ all_names :: [Name] -- All the defns; no dups eliminated
+ all_names = [name | avail <- avails, name <- availNames avail]
--- ToDo: b_names and b_keys being defined in this module !!!
+ 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_ (addErr . dupDeclErr) dups `thenM_`
-newGlobalName locn maybe_exp rdr
- = getExtraRn `thenRn` \ (_,b_keys,exp_fn,occ_fn) ->
- getModuleRn `thenRn` \ mod ->
- rnGetUnique `thenRn` \ u ->
+ doptM Opt_NoImplicitPrelude `thenM` \ implicit_prelude ->
let
- (uniq, unqual)
- = case rdr of
- Qual m n -> (u, n)
- Unqual n -> case (lookupFM b_keys n) of
- Nothing -> (u, n)
- Just (key,_) -> (key, n)
-
- orig = if fromPrelude mod
- then (Unqual unqual)
- else (Qual mod unqual)
-
- exp = case maybe_exp of
- Just exp -> exp
- Nothing -> exp_fn n
-
- n = mkTopLevName uniq orig locn exp (occ_fn n)
+ 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
+ -- 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
+
+
+ -- 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,
+ -- we use -fno-implicit-prelude as a clue that the filter is
+ -- worth while. Really, it's only useful for Base and 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 avails, not avails' in
+ -- 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.
+ -- 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.
in
- addWarnIfRn (rdr == Unqual SLIT("negate")) (negateNameWarn (rdr, locn)) `thenRn_`
- addErrIfRn (isQual rdr) (qualNameErr "name in definition" (rdr, locn)) `thenRn_`
- returnRn n
+ returnM (gbl_env, imports)
\end{code}
-*********************************************************
-* *
-\subsection{Imported names}
-* *
-*********************************************************
-\begin{code}
-type ImportNameInfo = (GlobalNameInfo,
- FiniteMap (Module,FAST_STRING) RnName, -- values imported so far
- FiniteMap (Module,FAST_STRING) RnName, -- tycons/classes imported so far
- Name -> ExportFlag) -- import flag
-
-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_flags) ->
- let
- rec_imp_fm = addListToUFM_C lubExportFlag emptyUFM (bagToList rec_imp_flags)
+%*********************************************************
+%* *
+\subsection{Getting binders out of a declaration}
+%* *
+%*********************************************************
- rec_imp_fn :: Name -> ExportFlag
- rec_imp_fn n = case lookupUFM rec_imp_fm n of
- Nothing -> panic "RnNames:rec_imp_fn"
- Just flag -> flag
+@getLocalDeclBinders@ returns the names for a @RdrNameHsDecl@. It's
+used for both source code (from @importsFromLocalDecls@) and interface
+files (@loadDecl@ calls @getTyClDeclBinders@).
- i_info = (g_info, emptyFM, emptyFM, rec_imp_fn)
- in
- doImports iface_cache i_info us all_imps
- ) >>= \ (vals, tcs, unquals, fixes, errs, warns, _) ->
+ *** See "THE NAMING STORY" in HsDecls ****
- return (vals, tcs, imp_mods, unquals, fixes,
- imp_errs `unionBags` errs,
- imp_warns `unionBags` warns)
+\begin{code}
+getLocalDeclBinders :: Module -> HsGroup RdrName -> TcRn m [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 ->
+ mappM new_bndr (for_hs_bndrs ++ val_hs_bndrs) `thenM` \ simple_bndrs ->
+
+ returnM (tc_avails ++ map Avail simple_bndrs)
where
- (ok_imps, src_qprels) = partition not_qual_prel src_imps
- all_imps = qprel_imp ++ prel_imp ++ ok_imps
-
- not_qual_prel (ImportDecl mod qual _ _ _) = not (fromPrelude mod && qual)
-
- explicit_prelude_import
- = null [() | (ImportDecl mod qual _ _ _) <- ok_imps,
- fromPrelude mod && not qual]
+ new_bndr (rdr_name,loc) = newTopBinder mod rdr_name loc
- qprel_imp = if opt_NoImplicitPrelude
- then [{-the flag really means it: *NO* implicit "import Prelude" -}]
- else [ImportDecl pRELUDE True Nothing Nothing mkIfaceSrcLoc]
+ val_hs_bndrs = collectLocatedHsBinders val_decls
+ for_hs_bndrs = [(nm,loc) | ForeignImport nm _ _ _ loc <- foreign_decls]
- prel_imp = if not explicit_prelude_import || opt_NoImplicitPrelude
- then
- [{- no "import Prelude" -}]
- else
- [ImportDecl pRELUDE False Nothing Nothing mkIfaceSrcLoc]
+ new_tc tc_decl = mappM new_bndr (tyClDeclNames tc_decl) `thenM` \ names@(main_name:_) ->
+ returnM (AvailTC main_name names)
+\end{code}
- (uniq_imps, imp_dups) = removeDups cmp_mod all_imps
- cmp_mod (ImportDecl m1 _ _ _ _) (ImportDecl m2 _ _ _ _) = cmpPString m1 m2
- imp_mods = [ mod | ImportDecl mod _ _ _ _ <- uniq_imps ]
- imp_warns = listToBag (map dupImportWarn imp_dups)
- imp_errs = listToBag (map qualPreludeImportErr src_qprels)
+%************************************************************************
+%* *
+\subsection{Filtering imports}
+%* *
+%************************************************************************
+@filterImports@ takes the @ExportEnv@ telling what the imported module makes
+available, and filters it through the import spec (if any).
-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,imp_fn) us (imp:imps)
- = doImport iface_cache i_info us1 imp
- >>= \ (vals1, tcs1, unquals1, fixes1, errs1, warns1, imps1) ->
+\begin{code}
+filterImports :: ModuleName -- The module being imported
+ -> IsBootInterface -- Tells whether it's a {-# SOURCE #-} import
+ -> Maybe (Bool, [RdrNameIE]) -- Import spec; True => hiding
+ -> [AvailInfo] -- What's available
+ -> TcRn m ([AvailInfo], -- What's imported
+ NameSet) -- What was imported explicitly
+
+ -- Complains if import spec mentions things that the module doesn't export
+ -- Warns/informs if import spec contains duplicates.
+filterImports mod from Nothing imports
+ = returnM (imports, emptyNameSet)
+
+filterImports mod from (Just (want_hiding, import_items)) total_avails
+ = mappM get_item import_items `thenM` \ avails_w_explicits_s ->
let
- new_vals = [ (moduleNamePair rn, rn) | (_,rn) <- bagToList vals1,
- not (maybeToBool (lookupFM done_vals (moduleNamePair rn))) ]
- -- moduleNamePair computed twice
- ext_vals = addListToFM done_vals new_vals
-
- new_tcs = [ (moduleNamePair rn, rn) | (_,rn) <- bagToList tcs1,
- not (maybeToBool (lookupFM done_tcs (moduleNamePair rn))) ]
- ext_tcs = addListToFM done_tcs new_tcs
+ (item_avails, explicits_s) = unzip (concat avails_w_explicits_s)
+ explicits = foldl addListToNameSet emptyNameSet explicits_s
in
- doImports iface_cache (g_info,ext_vals,ext_tcs,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
- (us1, us2) = splitUniqSupply us
-
-
-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)) -- import flags
-
-doImport iface_cache info us (ImportDecl mod qual maybe_as maybe_spec src_loc)
- = cachedIface iface_cache mod >>= \ maybe_iface ->
- case maybe_iface of
- Failed err ->
- return (emptyBag, emptyBag, emptyBag, emptyBag,
- unitBag err, emptyBag, emptyBag)
- Succeeded iface ->
- let
- (b_vals, b_tcs, maybe_spec') = getBuiltins info mod maybe_spec
- (ies, chk_ies, get_errs) = getOrigIEs iface maybe_spec'
- 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 ->
- accumulate (map (getFixityDecl iface_cache) (bagToList ie_vals))
- >>= \ fix_maybes_errs ->
- let
- (chk_errs, chk_warns) = unzip chk_errs_warns
- (fix_maybes, fix_errs) = unzip fix_maybes_errs
-
- final_vals = mapBag fst_occ b_vals `unionBags` mapBag pair_occ ie_vals
- final_tcs = mapBag fst_occ b_tcs `unionBags` mapBag pair_occ ie_tcs
-
- unquals = if qual 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
- in
- return (final_vals, final_tcs, unquals, final_fixes,
- final_errs, final_warns, imp_flags)
+ if want_hiding then
+ let -- All imported; item_avails to be hidden
+ hidden = availsToNameSet item_avails
+ keep n = not (n `elemNameSet` hidden)
+ in
+ returnM (pruneAvails keep total_avails, emptyNameSet)
+ else
+ -- Just item_avails imported; nothing to be hidden
+ returnM (item_avails, explicits)
where
- as_mod = case maybe_as of {Nothing -> mod; Just as_this -> as_this}
- mk_occ str = if qual then Qual as_mod str else Unqual str
+ import_fm :: FiniteMap OccName AvailInfo
+ import_fm = listToFM [ (nameOccName name, avail)
+ | avail <- total_avails,
+ name <- availNames avail]
+ -- Even though availNames returns data constructors too,
+ -- they won't make any difference because naked entities like T
+ -- in an import list map to TcOccs, not VarOccs.
+
+ bale_out item = addErr (badImportItemErr mod from item) `thenM_`
+ returnM []
+
+ get_item :: RdrNameIE -> TcRn m [(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
+ -- both a class and a data constructor.
+ -- The [Name] is the list of explicitly-mentioned names
+ get_item item@(IEModuleContents _) = bale_out item
+
+ get_item item@(IEThingAll _)
+ = 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_`
+ returnM [(avail, [availName avail])]
+ Just avail -> returnM [(avail, [availName avail])]
+
+ get_item item@(IEThingAbs n)
+ | want_hiding -- hiding( C )
+ -- Here the 'C' can be a data constructor *or* a type/class
+ = case catMaybes [check_item item, check_item (IEVar data_n)] of
+ [] -> bale_out item
+ avails -> returnM [(a, []) | a <- avails]
+ -- The 'explicits' list is irrelevant when hiding
+ where
+ data_n = setRdrNameSpace n dataName
- fst_occ (str, rn) = (mk_occ str, rn)
- pair_occ rn = (mk_occ (getLocalName rn), rn)
- pair_as rn = (as_mod, rn)
+ get_item item
+ = case check_item item of
+ Nothing -> bale_out item
+ Just avail -> returnM [(avail, availNames avail)]
+ check_item item
+ | not (maybeToBool maybe_in_import_avails) ||
+ not (maybeToBool maybe_filtered_avail)
+ = Nothing
-getBuiltins (((b_val_names,b_tc_names),_,_,_),_,_,_) mod maybe_spec
- = case maybe_spec of
- Nothing -> (all_vals, all_tcs, Nothing)
+ | otherwise
+ = Just filtered_avail
+
+ where
+ wanted_occ = rdrNameOcc (ieName item)
+ maybe_in_import_avails = lookupFM import_fm wanted_occ
- Just (True, ies) -> -- hiding does not work for builtin names
- (all_vals, all_tcs, maybe_spec)
+ Just avail = maybe_in_import_avails
+ maybe_filtered_avail = filterAvail item avail
+ Just filtered_avail = maybe_filtered_avail
+\end{code}
- Just (False, ies) -> let
- (vals,tcs,ies_left) = do_builtin ies
- in
- (vals, tcs, Just (False, ies_left))
+\begin{code}
+filterAvail :: RdrNameIE -- Wanted
+ -> AvailInfo -- Available
+ -> Maybe AvailInfo -- Resulting available;
+ -- Nothing if (any of the) wanted stuff isn't there
+
+filterAvail ie@(IEThingWith want wants) avail@(AvailTC n ns)
+ | sub_names_ok = Just (AvailTC n (filter is_wanted ns))
+ | otherwise = Nothing
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 ((str,rn):rest)
- = (str, rn) `consBag` do_all_builtin rest
-
- do_builtin [] = (emptyBag,emptyBag,[])
- do_builtin (ie:ies)
- = let str = unqual_str (ie_name ie)
- in
- case (lookupFM b_tc_names str) 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)
- _ -> panic "importing builtin names (1)"
-
- Nothing ->
- case (lookupFM b_val_names str) 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)"
- where
- (vals, tcs, ies_left) = do_builtin ies
+ is_wanted name = nameOccName name `elem` wanted_occs
+ sub_names_ok = all (`elem` avail_occs) wanted_occs
+ avail_occs = map nameOccName ns
+ wanted_occs = map rdrNameOcc (want:wants)
+
+filterAvail (IEThingAbs _) (AvailTC n ns) = ASSERT( n `elem` ns )
+ Just (AvailTC n [n])
+
+filterAvail (IEThingAbs _) avail@(Avail n) = Just avail -- Type synonyms
+
+filterAvail (IEVar _) avail@(Avail n) = Just avail
+filterAvail (IEVar v) avail@(AvailTC n ns) = Just (AvailTC n (filter wanted ns))
+ where
+ wanted n = nameOccName n == occ
+ occ = rdrNameOcc v
+ -- The second equation happens if we import a class op, thus
+ -- import A( op )
+ -- where op is a class operation
+
+filterAvail (IEThingAll _) avail@(AvailTC _ _) = Just avail
+ -- We don't complain even if the IE says T(..), but
+ -- no constrs/class ops of T are available
+ -- Instead that's caught with a warning by the caller
+
+filterAvail ie avail = Nothing
+\end{code}
-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 (orig,ExportAbs)
- = ASSERT(isLexCon (getLocalName orig))
- IEThingAbs orig
-mkAllIE (orig, ExportAll)
- | isLexCon (getLocalName orig)
- = IEThingAll orig
- | otherwise
- = IEVar orig
-
-
-lookupIEs exps []
- = ([], emptyBag)
-lookupIEs exps (ie:ies)
- = case lookupFM exps (unqual_str (ie_name ie)) of
- Nothing ->
- (orig_ies, unknownImpSpecErr ie `consBag` errs)
- Just (orig,flag) ->
- (orig_ie orig flag ie ++ orig_ies,
- adderr_if (seen_ie orig orig_ies) (duplicateImpSpecErr ie) errs)
- where
- (orig_ies, errs) = lookupIEs exps ies
+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).
- orig_ie orig flag (IEVar n) = [(IEVar orig, flag)]
- orig_ie orig flag (IEThingAbs n) = [(IEThingAbs orig, flag)]
- orig_ie orig flag (IEThingAll n) = [(IEThingAll orig, flag)]
- orig_ie orig flag (IEThingWith n ns) = [(IEThingWith orig ns, flag)]
+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...
- seen_ie orig seen_ies = any (\ (ie,_) -> orig == ie_name ie) seen_ies
+\begin{code}
+type ExportAccum -- The type of the accumulating parameter of
+ -- the main worker function in exportsFromAvail
+ = ([ModuleName], -- 'module M's seen so far
+ ExportOccMap, -- Tracks exported occurrence names
+ AvailEnv) -- The accumulated exported stuff, kept in an env
+ -- so we can common-up related AvailInfos
+emptyExportAccum = ([], emptyFM, emptyAvailEnv)
+
+type ExportOccMap = FiniteMap OccName (Name, RdrNameIE)
+ -- 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
+ -- 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 }
-doOrigIEs iface_cache info mod src_loc us []
- = return (emptyBag,emptyBag,emptyBag,emptyBag,emptyBag)
+exports_from_avail export_items warn_dup_exports
+ (ImportAvails { imp_unqual = mod_avail_env,
+ imp_env = entity_avail_env })
+ = foldlM exports_from_item emptyExportAccum
+ export_items `thenM` \ (_, _, export_avail_map) ->
+ returnM (nameEnvElts export_avail_map)
-doOrigIEs iface_cache info mod src_loc us (ie:ies)
- = doOrigIE iface_cache info mod src_loc us1 ie
- >>= \ (vals1, tcs1, errs1, warns1, imps1) ->
- doOrigIEs iface_cache info mod src_loc us2 ies
- >>= \ (vals2, tcs2, errs2, warns2, imps2) ->
- return (vals1 `unionBags` vals2,
- tcs1 `unionBags` tcs2,
- errs1 `unionBags` errs2,
- warns1 `unionBags` warns2,
- imps1 `unionBags` imps2)
where
- (us1, us2) = splitUniqSupply us
-
-doOrigIE iface_cache info mod src_loc us ie
- = with_decl iface_cache (ie_name ie)
- (\ 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))
-
-checkOrigIE iface_cache (IEThingAll n, ExportAbs)
- = with_decl iface_cache n
- (\ 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
- (\ err -> (unitBag (\ mod locn -> err), emptyBag))
- (\ decl -> case decl of
- NewTypeSig _ con _ _ -> (check_with "constructrs" [con] ns, emptyBag)
- DataSig _ cons fields _ _ -> (check_with "constructrs (and fields)" (cons++fields) ns, emptyBag)
- ClassSig _ ops _ _ -> (check_with "class ops" ops ns, emptyBag))
+ exports_from_item :: ExportAccum -> RdrNameIE -> TcRn m 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
+
+ | 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
+ avails' = foldl addAvail avails mod_avails
+ in
+ 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 ->
+
+ -- 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 ->
+
+ -- Filter out the bits we want
+ case filterAvail ie avail of {
+ Nothing -> -- Not enough availability
+ addErr (exportItemErr ie) `thenM_`
+ returnM acc ;
+
+ 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' ->
+ returnM (mods, occs', addAvail avails export_avail)
+ }}}
+
+
+
+ok_item (IEThingAll _) (AvailTC _ [n]) = False
+ -- This occurs when you import T(..), but
+ -- only export T abstractly. The single [n]
+ -- in the AvailTC is the type or class itself
+ok_item _ _ = True
+
+check_occs :: Bool -> RdrNameIE -> ExportOccMap -> AvailInfo -> TcRn m ExportOccMap
+check_occs warn_dup_exports ie occs avail
+ = foldlM check occs (availNames avail)
where
- check_with str has rdrs
- | sortLt (<) (map getLocalName has) == sortLt (<) (map unqual_str rdrs)
- = emptyBag
- | otherwise
- = unitBag (withImpSpecErr str n has rdrs)
-
-checkOrigIE iface_cache other
- = return (emptyBag, emptyBag)
-
-
-with_decl iface_cache n do_err do_decl
- = cachedDecl iface_cache (isRdrLexCon n) n >>= \ maybe_decl ->
- case maybe_decl of
- Failed err -> return (do_err err)
- Succeeded decl -> return (do_decl decl)
-
-
-getFixityDecl iface_cache rn
- = let
- (mod, str) = moduleNamePair rn
- in
- cachedIface iface_cache 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) -> return (Just (InfixL rn i), emptyBag)
- Just (InfixR _ i) -> return (Just (InfixR rn i), emptyBag)
- Just (InfixN _ i) -> return (Just (InfixN rn i), emptyBag)
-
-ie_name (IEVar n) = n
-ie_name (IEThingAbs n) = n
-ie_name (IEThingAll n) = n
-ie_name (IEThingWith n _) = n
-
-unqual_str (Unqual str) = str
-unqual_str q@(Qual _ _) = panic "unqual_str"
-
-adderr_if True err errs = err `consBag` errs
-adderr_if False err errs = errs
+ check occs name
+ = case lookupFM occs name_occ of
+ 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
+ where
+ name_occ = nameOccName name
\end{code}
-*********************************************************
-* *
-\subsection{Actually creating the imported names}
-* *
-*********************************************************
+%*********************************************************
+%* *
+\subsection{Unused names}
+%* *
+%*********************************************************
\begin{code}
-getIfaceDeclNames :: RdrNameIE -> 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 ->
- mapRn (newImportedName False src_loc (Just (nameExportFlag tycon_name))
- (Just (nameImportFlag tycon_name)))
- cons `thenRn` \ con_names ->
- mapRn (newImportedName False src_loc (Just (nameExportFlag tycon_name))
- (Just (nameImportFlag tycon_name)))
- 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
+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_`
+ 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]
+
+ -- 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_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
+
+ -- 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 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
+
+ -- 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
+ minimal_imports :: FiniteMap ModuleName AvailEnv
+ minimal_imports0 = emptyFM
+ 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_parent = p,
+ gre_prov = NonLocalDef (UserImport m _ _)}) acc
+ = addToFM_C plusAvailEnv acc (moduleName m)
+ (unitAvailEnv (mk_avail n p))
+ 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
+
+ add_inst_mod m acc
+ | m `elemFM` acc = acc -- We import something already
+ | otherwise = addToFM acc m emptyAvailEnv
+ -- Add an empty collection of imports for a module
+ -- from which we have sucked only instance decls
+
+ -- unused_imp_mods are the directly-imported modules
+ -- that are not mentioned in minimal_imports1
+ -- [Note: not 'minimal_imports', because that includes direcly-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]
+
+ module_unused :: Module -> Bool
+ module_unused mod = moduleName mod `elem` unused_imp_mods
+
+
+-- ToDo: deal with original imports with 'qualified' and 'as M' clauses
+printMinimalImports :: FiniteMap ModuleName AvailEnv -- Minimal imports
+ -> TcRn m ()
+printMinimalImports imps
+ = ifOptM Opt_D_dump_minimal_imports $ do {
+
+ mod_ies <- mappM to_ies (fmToList imps) ;
+ this_mod <- getModule ;
+ rdr_env <- getGlobalRdrEnv ;
+ ioToTcRn (do { h <- openFile (mkFilename this_mod) WriteMode ;
+ printForUser h (unQualInScope rdr_env)
+ (vcat (map ppr_mod_ie mod_ies)) })
+ }
+ where
+ mkFilename this_mod = moduleNameUserString (moduleName this_mod) ++ ".imports"
+ ppr_mod_ie (mod_name, ies)
+ | mod_name == pRELUDE_Name
+ = 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 -> TcRn m (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)
+ = loadInterface (text "Compute minimal imports from" <+> ppr n_mod)
+ n_mod ImportBySystem `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)
+ where
+ n_mod = moduleName (nameModule n)
\end{code}
-*********************************************************
-* *
-\subsection{Creating a new imported name}
-* *
-*********************************************************
-\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
- = getExtraRn `thenRn` \ ((_,b_keys,exp_fn,occ_fn),done_vals,done_tcs,imp_fn) ->
- case if tycon_or_class
- then lookupFM done_tcs (moduleNamePair rdr)
- else lookupFM done_vals (moduleNamePair rdr)
- of
- Just rn -> returnRn (getName rn)
- Nothing ->
- rnGetUnique `thenRn` \ u ->
- let
- uniq = case rdr of
- Qual m n -> u
- Unqual n -> case lookupFM b_keys n of
- Nothing -> u
- Just (key,_) -> key
-
- exp = case maybe_exp of
- Just exp -> exp
- Nothing -> exp_fn n
-
- imp = case maybe_imp of
- Just imp -> imp
- Nothing -> imp_fn n
-
- n = mkImportedName uniq rdr imp locn exp (occ_fn n)
- in
- returnRn n
-\end{code}
+%************************************************************************
+%* *
+\subsection{Errors}
+%* *
+%************************************************************************
\begin{code}
-globalDupNamesErr (rn1:dup_rns) sty
- = ppAboves (item1 : map dup_item dup_rns)
+badImportItemErr mod from ie
+ = sep [ptext SLIT("Module"), quotes (ppr mod), source_import,
+ ptext SLIT("does not export"), quotes (ppr ie)]
where
- item1 = addShortErrLocLine (getSrcLoc rn1) (\ sty ->
- ppBesides [ppStr "multiple declarations of `",
- pprNonSym sty rn1, ppStr "' ", pp_descrip rn1]) sty
-
- dup_item rn
- = addShortErrLocLine (getSrcLoc rn) (\ sty ->
- ppBesides [ppStr "here was another declaration of `",
- pprNonSym sty rn, ppStr "' ", pp_descrip rn]) sty
-
- 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)
+ source_import = case from of
+ True -> ptext SLIT("(hi-boot interface)")
+ other -> empty
+
+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),
+ 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 occ_name ie1 ie2
+ = hsep [ptext SLIT("The export items"), quotes (ppr ie1)
+ ,ptext SLIT("and"), quotes (ppr ie2)
+ ,ptext SLIT("create conflicting exports for"), quotes (ppr occ_name)]
+
+dupDeclErr (n:ns)
+ = vcat [ptext SLIT("Multiple declarations of") <+> quotes (ppr n),
+ nest 4 (vcat (map ppr sorted_locs))]
where
- item1 = addShortErrLocLine locn1 (\ sty ->
- ppCat [ppStr "multiple imports from module", ppPStr m1]) sty
-
- dup_item (ImportDecl m _ _ _ locn)
- = addShortErrLocLine locn (\ sty ->
- ppCat [ppStr "here was another import from module", ppPStr m]) sty
-
-qualPreludeImportErr (ImportDecl m _ _ _ locn)
- = addShortErrLocLine locn (\ sty ->
- ppCat [ppStr "qualified import form prelude module", ppPStr m])
-
-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
- = addShortErrLocLine 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 "'"])
+ sorted_locs = sortLt occ'ed_before (map nameSrcLoc (n:ns))
+ occ'ed_before a b = LT == compare a b
+
+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}