\section[RnNames]{Extracting imported and top-level names in scope}
\begin{code}
+{-# OPTIONS -w #-}
+-- The above warning supression flag is a temporary kludge.
+-- While working on this module you are encouraged to remove it and fix
+-- any warnings in the module. See
+-- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
+-- for details
+
module RnNames (
rnImports, importsFromLocalDecls,
rnExports,
getLocalDeclBinders, extendRdrEnvRn,
- reportUnusedNames, reportDeprecations
+ reportUnusedNames, finishDeprecations,
) where
#include "HsVersions.h"
-import DynFlags ( DynFlag(..), GhcMode(..), DynFlags(..) )
+import DynFlags
import HsSyn ( IE(..), ieName, ImportDecl(..), LImportDecl,
- ForeignDecl(..), HsGroup(..), HsValBinds(..),
+ ForeignDecl(..), HsGroup(..), HsValBindsLR(..),
Sig(..), collectHsBindLocatedBinders, tyClDeclNames,
- instDeclATs, isIdxTyDecl,
+ instDeclATs, isFamInstDecl,
LIE )
import RnEnv
import RnHsDoc ( rnHsDoc )
import IfaceEnv ( ifaceExportNames )
-import LoadIface ( loadSrcInterface )
+import LoadIface ( loadSrcInterface, loadSysInterface )
import TcRnMonad hiding (LIE)
import PrelNames
import Module
import Name
import NameEnv
+import UniqFM
import NameSet
-import OccName ( srcDataName, pprNonVarNameSpace,
- occNameSpace,
- OccEnv, mkOccEnv, mkOccEnv_C, lookupOccEnv,
- emptyOccEnv, extendOccEnv )
-import HscTypes ( GenAvailInfo(..), AvailInfo, availNames, availName,
- HomePackageTable, PackageIfaceTable,
- mkPrintUnqualified, availsToNameSet,
- Deprecs(..), ModIface(..), Dependencies(..),
- lookupIfaceByModule, ExternalPackageState(..)
- )
-import RdrName ( RdrName, rdrNameOcc, setRdrNameSpace, Parent(..),
- GlobalRdrEnv, mkGlobalRdrEnv, GlobalRdrElt(..),
- emptyGlobalRdrEnv, plusGlobalRdrEnv, globalRdrEnvElts,
- extendGlobalRdrEnv, lookupGlobalRdrEnv,
- lookupGRE_RdrName, lookupGRE_Name,
- Provenance(..), ImportSpec(..), ImpDeclSpec(..), ImpItemSpec(..),
- importSpecLoc, importSpecModule, isLocalGRE, pprNameProvenance,
- unQualSpecOK, qualSpecOK )
+import OccName
+import HscTypes
+import RdrName
import Outputable
import Maybes
-import SrcLoc ( Located(..), mkGeneralSrcSpan, getLoc,
- unLoc, noLoc, srcLocSpan, SrcSpan )
+import SrcLoc
import FiniteMap
import ErrUtils
-import BasicTypes ( DeprecTxt )
+import BasicTypes ( DeprecTxt, Fixity )
import DriverPhases ( isHsBoot )
import Util
import ListSetOps
\begin{code}
rnImports :: [LImportDecl RdrName]
- -> RnM ([LImportDecl Name], GlobalRdrEnv, ImportAvails)
+ -> RnM ([LImportDecl Name], GlobalRdrEnv, ImportAvails,AnyHpcUsage)
rnImports imports
-- PROCESS IMPORT DECLS
(source, ordinary) = partition is_source_import imports
is_source_import (L _ (ImportDecl _ is_boot _ _ _)) = is_boot
+ ifOptM Opt_WarnImplicitPrelude (
+ when (notNull prel_imports) $ addWarn (implicitPreludeWarn)
+ )
+
stuff1 <- mapM (rnImportDecl this_mod) (prel_imports ++ ordinary)
stuff2 <- mapM (rnImportDecl this_mod) source
- let (decls, rdr_env, imp_avails) = combine (stuff1 ++ stuff2)
- return (decls, rdr_env, imp_avails)
+ let (decls, rdr_env, imp_avails,hpc_usage) = combine (stuff1 ++ stuff2)
+ return (decls, rdr_env, imp_avails,hpc_usage)
where
- combine :: [(LImportDecl Name, GlobalRdrEnv, ImportAvails)]
- -> ([LImportDecl Name], GlobalRdrEnv, ImportAvails)
- combine = foldr plus ([], emptyGlobalRdrEnv, emptyImportAvails)
- where plus (decl, gbl_env1, imp_avails1)
- (decls, gbl_env2, imp_avails2)
+ combine :: [(LImportDecl Name, GlobalRdrEnv, ImportAvails,AnyHpcUsage)]
+ -> ([LImportDecl Name], GlobalRdrEnv, ImportAvails,AnyHpcUsage)
+ combine = foldr plus ([], emptyGlobalRdrEnv, emptyImportAvails,False)
+ where plus (decl, gbl_env1, imp_avails1,hpc_usage1)
+ (decls, gbl_env2, imp_avails2,hpc_usage2)
= (decl:decls,
gbl_env1 `plusGlobalRdrEnv` gbl_env2,
- imp_avails1 `plusImportAvails` imp_avails2)
+ imp_avails1 `plusImportAvails` imp_avails2,
+ hpc_usage1 || hpc_usage2)
mkPrelImports :: Module -> Bool -> [LImportDecl RdrName] -> [LImportDecl RdrName]
-- Consruct the implicit declaration "import Prelude" (or not)
rnImportDecl :: Module
-> LImportDecl RdrName
- -> RnM (LImportDecl Name, GlobalRdrEnv, ImportAvails)
+ -> RnM (LImportDecl Name, GlobalRdrEnv, ImportAvails,AnyHpcUsage)
rnImportDecl this_mod (L loc (ImportDecl loc_imp_mod_name want_boot
qual_only as_mod imp_details))
let
imp_mod = mi_module iface
deprecs = mi_deprecs iface
- is_orph = mi_orphan iface
+ orph_iface = mi_orphan iface
has_finsts = mi_finsts iface
deps = mi_deps iface
let
-- Compute new transitive dependencies
- orphans | is_orph = ASSERT( not (imp_mod `elem` dep_orphs deps) )
- imp_mod : dep_orphs deps
- | otherwise = dep_orphs deps
+ orphans | orph_iface = ASSERT( not (imp_mod `elem` dep_orphs deps) )
+ imp_mod : dep_orphs deps
+ | otherwise = dep_orphs deps
finsts | has_finsts = ASSERT( not (imp_mod `elem` dep_finsts deps) )
imp_mod : dep_finsts deps
other -> False
imports = ImportAvails {
- imp_mods = unitModuleEnv imp_mod (imp_mod, import_all, loc),
+ imp_mods = unitModuleEnv imp_mod (imp_mod, [(qual_mod_name, import_all, loc)]),
imp_orphs = orphans,
imp_finsts = finsts,
imp_dep_mods = mkModDeps dependent_mods,
let new_imp_decl = L loc (ImportDecl loc_imp_mod_name want_boot
qual_only as_mod new_imp_details)
- returnM (new_imp_decl, gbl_env, imports)
+ returnM (new_imp_decl, gbl_env, imports, mi_hpc iface)
)
warnRedundantSourceImport mod_name
* the ImportAvails
created by its bindings.
-Complain about duplicate bindings
-
\begin{code}
-importsFromLocalDecls :: HsGroup RdrName -> RnM TcGblEnv
-importsFromLocalDecls group
+-- Bool determines shadowing:
+-- true: names in the group should shadow other UnQuals
+-- with the same OccName (used in Template Haskell)
+-- false: duplicates should be reported as an error
+--
+-- The UniqFM (OccName -> FixItem) associates a Name's OccName's
+-- FastString with a fixity declaration (that needs the actual OccName
+-- to be plugged in). This fixity must be brought into scope when such
+-- a Name is.
+importsFromLocalDecls :: Bool -> HsGroup RdrName -> UniqFM (Located Fixity) -> RnM TcGblEnv
+importsFromLocalDecls shadowP group fixities
= do { gbl_env <- getGblEnv
; avails <- getLocalDeclBinders gbl_env group
- ; rdr_env' <- extendRdrEnvRn (tcg_rdr_env gbl_env) avails
+ ; (rdr_env', fix_env') <- extendRdrEnvRn shadowP (tcg_rdr_env gbl_env,
+ tcg_fix_env gbl_env)
+ avails fixities
; traceRn (text "local avails: " <> ppr avails)
- ; returnM (gbl_env { tcg_rdr_env = rdr_env' })
+ ; returnM (gbl_env { tcg_rdr_env = rdr_env',
+ tcg_fix_env = fix_env'})
}
-extendRdrEnvRn :: GlobalRdrEnv -> [AvailInfo] -> RnM GlobalRdrEnv
+-- Bool determines shadowing as in importsFromLocalDecls.
+-- UniqFM FixItem is the same as in importsFromLocalDecls.
+--
-- Add the new locally-bound names one by one, checking for duplicates as
-- we do so. Remember that in Template Haskell the duplicates
--- might *already be* in the GlobalRdrEnv from higher up the module
-extendRdrEnvRn rdr_env avails
- = foldlM add_local rdr_env (gresFromAvails LocalDef avails)
- where
- add_local rdr_env gre
- | gres <- lookupGlobalRdrEnv rdr_env (nameOccName (gre_name gre))
- , (dup_gre:_) <- filter isLocalGRE gres -- Check for existing *local* defns
- = do { addDupDeclErr (gre_name dup_gre) (gre_name gre)
- ; return rdr_env }
- | otherwise
- = return (extendGlobalRdrEnv rdr_env gre)
+-- might *already be* in the GlobalRdrEnv from higher up the module.
+--
+-- Also update the FixityEnv with the fixities for the names brought into scope.
+--
+-- Note that the return values are the extensions of the two inputs,
+-- not the extras relative to them.
+extendRdrEnvRn :: Bool -> (GlobalRdrEnv, NameEnv FixItem)
+ -> [AvailInfo] -> UniqFM (Located Fixity) -> RnM (GlobalRdrEnv, NameEnv FixItem)
+extendRdrEnvRn shadowP (rdr_env, fix_env) avails fixities =
+ let -- if there is a fixity decl for the gre,
+ -- add it to the fixity env
+ extendFixEnv env gre =
+ let name = gre_name gre
+ occ = nameOccName name
+ curKey = occNameFS occ in
+ case lookupUFM fixities curKey of
+ Nothing -> env
+ Just (L _ fi) -> extendNameEnv env name (FixItem occ fi)
+
+ (rdr_env_to_extend, extender) =
+ if shadowP
+ then -- when shadowing is on,
+ -- (1) we need to remove the existing Unquals for the
+ -- names we're extending the env with
+ -- (2) but extending the env is simple
+ let names = concatMap availNames avails
+ new_occs = map nameOccName names
+ trimmed_rdr_env = hideSomeUnquals rdr_env new_occs
+ in
+ (trimmed_rdr_env,
+ \(cur_rdr_env, cur_fix_env) -> \gre ->
+ return (extendGlobalRdrEnv cur_rdr_env gre,
+ extendFixEnv cur_fix_env gre))
+ else -- when shadowing is off,
+ -- (1) we don't munge the incoming env
+ -- (2) but we need to check for dups when extending
+ (rdr_env,
+ \(cur_rdr_env, cur_fix_env) -> \gre ->
+ let gres = lookupGlobalRdrEnv cur_rdr_env (nameOccName (gre_name gre))
+ in case filter isLocalGRE gres of -- Check for existing *local* defns
+ dup_gre:_ -> do { addDupDeclErr (gre_name dup_gre) (gre_name gre)
+ ; return (cur_rdr_env, cur_fix_env) }
+ [] -> return (extendGlobalRdrEnv cur_rdr_env gre,
+ extendFixEnv cur_fix_env gre))
+ in foldlM extender (rdr_env_to_extend, fix_env) (gresFromAvails LocalDef avails)
\end{code}
@getLocalDeclBinders@ returns the names for an @HsDecl@. It's
*** See "THE NAMING STORY" in HsDecls ****
-Instances of indexed types
+Instances of type families
~~~~~~~~~~~~~~~~~~~~~~~~~~
Indexed data/newtype instances contain data constructors that we need to
collect, too. Moreover, we need to descend into the data/newtypes instances
don't return it in the 'AvailInfo'.
\begin{code}
+-- Note: this function does NOT get the binders of the ValBinds that
+-- will be bound during renaming
getLocalDeclBinders :: TcGblEnv -> HsGroup RdrName -> RnM [AvailInfo]
getLocalDeclBinders gbl_env (HsGroup {hs_valds = ValBindsIn val_decls val_sigs,
- hs_tyclds = tycl_decls,
- hs_instds = inst_decls,
- hs_fords = foreign_decls })
+ hs_tyclds = tycl_decls,
+ hs_instds = inst_decls,
+ hs_fords = foreign_decls })
= do { tc_names_s <- mappM new_tc tycl_decls
; at_names_s <- mappM inst_ats inst_decls
; val_names <- mappM new_simple val_bndrs
where
mod = tcg_mod gbl_env
is_hs_boot = isHsBoot (tcg_src gbl_env) ;
- val_bndrs | is_hs_boot = sig_hs_bndrs
- | otherwise = for_hs_bndrs ++ val_hs_bndrs
- -- In a hs-boot file, the value binders come from the
- -- *signatures*, and there should be no foreign binders
+
+ for_hs_bndrs = [nm | L _ (ForeignImport nm _ _) <- foreign_decls]
+
+ -- In a hs-boot file, the value binders come from the
+ -- *signatures*, and there should be no foreign binders
+ val_bndrs | is_hs_boot = [nm | L _ (TypeSig nm _) <- val_sigs]
+ | otherwise = for_hs_bndrs
new_simple rdr_name = do
nm <- newTopSrcBinder mod rdr_name
return (Avail nm)
- sig_hs_bndrs = [nm | L _ (TypeSig nm _) <- val_sigs]
- val_hs_bndrs = collectHsBindLocatedBinders val_decls
- for_hs_bndrs = [nm | L _ (ForeignImport nm _ _) <- foreign_decls]
-
new_tc tc_decl
- | isIdxTyDecl (unLoc tc_decl)
+ | isFamInstDecl (unLoc tc_decl)
= do { main_name <- lookupFamInstDeclBndr mod main_rdr
; sub_names <- mappM (newTopSrcBinder mod) sub_rdrs
; return (AvailTC main_name sub_names) }
filterImports iface decl_spec (Just (want_hiding, import_items)) all_avails
= do -- check for errors, convert RdrNames to Names
- opt_indexedtypes <- doptM Opt_IndexedTypes
- items1 <- mapM (lookup_lie opt_indexedtypes) import_items
+ opt_typeFamilies <- doptM Opt_TypeFamilies
+ items1 <- mapM (lookup_lie opt_typeFamilies) import_items
let items2 :: [(LIE Name, AvailInfo)]
items2 = concat items1
(name, AvailTC name subs, Just parent)
lookup_lie :: Bool -> LIE RdrName -> TcRn [(LIE Name, AvailInfo)]
- lookup_lie opt_indexedtypes (L loc ieRdr)
+ lookup_lie opt_typeFamilies (L loc ieRdr)
= do
stuff <- setSrcSpan loc $
- case lookup_ie opt_indexedtypes ieRdr of
+ case lookup_ie opt_typeFamilies ieRdr of
Failed err -> addErr err >> return []
Succeeded a -> return a
checkDodgyImport stuff
-- AvailInfos for the data constructors and the family (as they have
-- different parents). See the discussion at occ_env.
lookup_ie :: Bool -> IE RdrName -> MaybeErr Message [(IE Name,AvailInfo)]
- lookup_ie opt_indexedtypes ie
+ lookup_ie opt_typeFamilies ie
= let bad_ie = Failed (badImportItemErr iface decl_spec ie)
lookup_name rdrName =
children <- if any isNothing mb_children
then bad_ie
else return (catMaybes mb_children)
- -- check for proper import of indexed types
- when (not opt_indexedtypes && any isTyConName children) $
+ -- check for proper import of type families
+ when (not opt_typeFamilies && any isTyConName children) $
Failed (typeItemErr (head . filter isTyConName $ children)
(text "in import list"))
case mb_parent of
-- it came from. It's illegal to export two distinct things
-- that have the same occurrence name
-rnExports :: Bool -- False => no 'module M(..) where' header at all
+rnExports :: Bool -- False => no 'module M(..) where' header at all
-> Maybe [LIE RdrName] -- Nothing => no explicit export list
- -> RnM (Maybe [LIE Name], [AvailInfo])
+ -> TcGblEnv
+ -> RnM TcGblEnv
-- Complains if two distinct exports have same OccName
-- Warns about identical exports.
-- Complains about exports items not in scope
-rnExports explicit_mod exports
- = do TcGblEnv { tcg_mod = this_mod,
- tcg_rdr_env = rdr_env,
- tcg_imports = imports } <- getGblEnv
-
+rnExports explicit_mod exports
+ tcg_env@(TcGblEnv { tcg_mod = this_mod,
+ tcg_rdr_env = rdr_env,
+ tcg_imports = imports })
+ = do {
-- 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
- ghc_mode <- getGhcMode
- real_exports <-
- case () of
- () | explicit_mod
- -> return exports
- | ghc_mode == Interactive
- -> return Nothing
- | otherwise
- -> do mainName <- lookupGlobalOccRn main_RDR_Unqual
- return (Just ([noLoc (IEVar main_RDR_Unqual)]))
- -- ToDo: the 'noLoc' here is unhelpful if 'main' turns
- -- out to be out of scope
-
- (exp_spec, avails) <- exports_from_avail real_exports rdr_env imports this_mod
-
- return (exp_spec, nubAvails avails) -- Combine families
+ ; dflags <- getDOpts
+ ; let real_exports
+ | explicit_mod = exports
+ | ghcLink dflags == LinkInMemory = Nothing
+ | otherwise = Just ([noLoc (IEVar main_RDR_Unqual)])
+ -- ToDo: the 'noLoc' here is unhelpful if 'main'
+ -- turns out to be out of scope
+
+ ; (rn_exports, avails) <- exports_from_avail real_exports rdr_env imports this_mod
+ ; let final_avails = nubAvails avails -- Combine families
+
+ ; return (tcg_env { tcg_exports = final_avails,
+ tcg_rn_exports = case tcg_rn_exports tcg_env of
+ Nothing -> Nothing
+ Just _ -> rn_exports,
+ tcg_dus = tcg_dus tcg_env `plusDU`
+ usesOnly (availsToNameSet final_avails) }) }
+
exports_from_avail :: Maybe [LIE RdrName]
-- Nothing => no explicit export list
kids_env :: NameEnv [Name] -- Maps a parent to its in-scope children
kids_env = mkChildEnv (globalRdrEnvElts rdr_env)
+ imported_modules = [ qual_name
+ | (_, xs) <- moduleEnvElts $ imp_mods imports,
+ (qual_name, _, _) <- xs ]
+
exports_from_item :: ExportAccum -> LIE RdrName -> RnM ExportAccum
exports_from_item acc@(ie_names, occs, exports)
(L loc ie@(IEModuleContents mod))
| otherwise
= do { implicit_prelude <- doptM Opt_ImplicitPrelude
- ; let gres = filter (isModuleExported implicit_prelude mod)
- (globalRdrEnvElts rdr_env)
+ ; let { exportValid = (mod `elem` imported_modules)
+ || (moduleName this_mod == mod)
+ ; gres = filter (isModuleExported implicit_prelude mod)
+ (globalRdrEnvElts rdr_env)
+ }
- ; warnIf (null gres) (nullModuleExport mod)
+ ; checkErr exportValid (moduleNotImported mod)
+ ; warnIf (exportValid && null gres) (nullModuleExport mod)
; occs' <- check_occs ie occs (map gre_name gres)
-- This check_occs not only finds conflicts
return (IEVar (gre_name gre), greAvail gre)
lookup_ie (IEThingAbs rdr)
- = do name <- lookupGlobalOccRn rdr
- case lookupGRE_RdrName rdr rdr_env of
- [] -> panic "RnNames.lookup_ie"
- elt:_ -> case gre_par elt of
- NoParent -> return (IEThingAbs name,
- AvailTC name [name])
- ParentIs p -> return (IEThingAbs name,
- AvailTC p [name])
+ = do gre <- lookupGreRn rdr
+ let name = gre_name gre
+ case gre_par gre of
+ NoParent -> return (IEThingAbs name,
+ AvailTC name [name])
+ ParentIs p -> return (IEThingAbs name,
+ AvailTC p [name])
lookup_ie ie@(IEThingAll rdr)
= do name <- lookupGlobalOccRn rdr
then do addErr (exportItemErr ie)
return (IEThingWith name [], AvailTC name [name])
else do let names = catMaybes mb_names
- optIdxTypes <- doptM Opt_IndexedTypes
- when (not optIdxTypes && any isTyConName names) $
+ optTyFam <- doptM Opt_TypeFamilies
+ when (not optTyFam && any isTyConName names) $
addErr (typeItemErr ( head
. filter isTyConName
$ names )
%*********************************************************
\begin{code}
-reportDeprecations :: DynFlags -> TcGblEnv -> RnM ()
-reportDeprecations dflags tcg_env
- = ifOptM Opt_WarnDeprecations $
- do { (eps,hpt) <- getEpsAndHpt
+finishDeprecations :: DynFlags -> Maybe DeprecTxt
+ -> TcGblEnv -> RnM TcGblEnv
+-- (a) Report usasge of deprecated imports
+-- (b) If the whole module is deprecated, update tcg_deprecs
+-- All this happens only once per module
+finishDeprecations dflags mod_deprec tcg_env
+ = do { (eps,hpt) <- getEpsAndHpt
+ ; ifOptM Opt_WarnDeprecations $
+ mapM_ (check hpt (eps_PIT eps)) all_gres
-- By this time, typechecking is complete,
-- so the PIT is fully populated
- ; mapM_ (check hpt (eps_PIT eps)) all_gres }
+
+ -- Deal with a module deprecation; it overrides all existing deprecs
+ ; let new_deprecs = case mod_deprec of
+ Just txt -> DeprecAll txt
+ Nothing -> tcg_deprecs tcg_env
+ ; return (tcg_env { tcg_deprecs = new_deprecs }) }
where
used_names = allUses (tcg_dus tcg_env)
-- Report on all deprecated uses; hence allUses
check hpt pit gre@(GRE {gre_name = name, gre_prov = Imported (imp_spec:_)})
| name `elemNameSet` used_names
- , Just deprec_txt <- lookupDeprec dflags hpt pit gre
+ , Just deprec_txt <- lookupImpDeprec dflags hpt pit gre
= addWarnAt (importSpecLoc imp_spec)
(sep [ptext SLIT("Deprecated use of") <+>
pprNonVarNameSpace (occNameSpace (nameOccName name)) <+>
-- the defn of a non-deprecated thing, when changing a module's
-- interface
-lookupDeprec :: DynFlags -> HomePackageTable -> PackageIfaceTable
- -> GlobalRdrElt -> Maybe DeprecTxt
-lookupDeprec dflags hpt pit gre
+lookupImpDeprec :: DynFlags -> HomePackageTable -> PackageIfaceTable
+ -> GlobalRdrElt -> Maybe DeprecTxt
+-- The name is definitely imported, so look in HPT, PIT
+lookupImpDeprec dflags hpt pit gre
= case lookupIfaceByModule dflags hpt pit (nameModule name) of
Just iface -> mi_dep_fn iface name `seqMaybe` -- Bleat if the thing, *or
case gre_par gre of
ParentIs p -> mi_dep_fn iface p -- its parent*, is deprec'd
NoParent -> Nothing
- Nothing
- | isWiredInName name -> 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 name)
- -- By now all the interfaces should have been loaded
+
+ Nothing -> Nothing -- See Note [Used names with interface not loaded]
where
name = gre_name gre
\end{code}
+Note [Used names with interface not loaded]
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+By now all the interfaces should have been loaded,
+because reportDeprecations happens after typechecking.
+However, it's still (just) possible to to find a used
+Name whose interface hasn't been loaded:
+
+a) It might be a WiredInName; in that case we may not load
+ its interface (although we could).
+
+b) It might be GHC.Real.fromRational, or GHC.Num.fromInteger
+ These are seen as "used" by the renamer (if -fno-implicit-prelude)
+ is on), but the typechecker may discard their uses
+ if in fact the in-scope fromRational is GHC.Read.fromRational,
+ (see tcPat.tcOverloadedLit), and the typechecker sees that the type
+ is fixed, say, to GHC.Base.Float (see Inst.lookupSimpleInst).
+ In that obscure case it won't force the interface in.
+
+In both cases we simply don't permit deprecations;
+this is, after all, wired-in stuff.
+
+
%*********************************************************
%* *
Unused names
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})
- = not (all (module_unused . importSpecModule) imp_specs)
- && or [exp | ImpSpec { is_item = ImpSome { is_explicit = exp } } <- imp_specs]
- -- Don't complain about unused imports if we've already said the
- -- entire import is unused
- unused_imp other = False
+ unused_imports :: [GlobalRdrElt]
+ unused_imports = mapCatMaybes unused_imp defined_but_not_used
+ unused_imp :: GlobalRdrElt -> Maybe GlobalRdrElt -- Result has trimmed Imported provenances
+ unused_imp gre@(GRE {gre_prov = LocalDef}) = Nothing
+ unused_imp gre@(GRE {gre_prov = Imported imp_specs})
+ | null trimmed_specs = Nothing
+ | otherwise = Just (gre {gre_prov = Imported trimmed_specs})
+ where
+ trimmed_specs = filter report_if_unused imp_specs
-- 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
-- qualified imports into account. But it's an improvement.
add_expall mod acc = addToFM_C plusAvailEnv acc mod emptyAvailEnv
- add_inst_mod (mod,_,_) acc
+ add_inst_mod (mod, _) acc
| mod_name `elemFM` acc = acc -- We import something already
| otherwise = addToFM acc mod_name emptyAvailEnv
where
imports = tcg_imports gbl_env
- direct_import_mods :: [(Module, Bool, SrcSpan)]
+ direct_import_mods :: [(Module, [(ModuleName, Bool, SrcSpan)])]
-- See the type of the imp_mods for this triple
direct_import_mods = moduleEnvElts (imp_mods imports)
-- [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_name,loc) | (mod,no_imp,loc) <- direct_import_mods,
+ -- BUG WARNING: this code is generally buggy
+ unused_imp_mods :: [(ModuleName, SrcSpan)]
+ unused_imp_mods = [(mod_name,loc)
+ | (mod, xs) <- direct_import_mods,
+ (_, no_imp, loc) <- xs,
let mod_name = moduleName mod,
not (mod_name `elemFM` minimal_imports1),
mod /= pRELUDE,
module_unused :: ModuleName -> Bool
module_unused mod = any (((==) mod) . fst) unused_imp_mods
+ report_if_unused :: ImportSpec -> Bool
+ -- Do we want to report this as an unused import?
+ report_if_unused (ImpSpec {is_decl = d, is_item = i})
+ = not (module_unused (is_mod d)) -- Not if we've already said entire import is unused
+ && isExplicitItem i -- Only if the import was explicit
+
---------------------
warnDuplicateImports :: [GlobalRdrElt] -> RnM ()
-- Given the GREs for names that are used, figure out which imports
warnDuplicateImports gres
= ifOptM Opt_WarnUnusedImports $
sequenceM_ [ warn name pr
- -- The 'head' picks the first offending group
- -- for this particular name
| GRE { gre_name = name, gre_prov = Imported imps } <- gres
, pr <- redundants imps ]
where
redundants imps
= [ (red_imp, cov_imp)
| red_imp <- imps
+ , isExplicitItem (is_item red_imp)
+ -- Complain only about redundant imports
+ -- mentioned explicitly by the user
, cov_imp <- take 1 (filter (covers red_imp) imps) ]
+ -- The 'take 1' picks the first offending group
+ -- for this particular name
-- "red_imp" is a putative redundant import
-- "cov_imp" potentially covers it
= False -- They bring into scope different qualified names
| not (is_qual red_decl) && is_qual cov_decl
= False -- Covering one doesn't bring unqualified name into scope
+ | otherwise
+ = not (isExplicitItem cov_item) -- Redundant one is selective and covering one isn't
+ || red_later -- or both are explicit; tie-break using red_later
+{-
| red_selective
= not cov_selective -- Redundant one is selective and covering one isn't
|| red_later -- Both are explicit; tie-break using red_later
= not cov_selective -- Neither import is selective
&& (is_mod red_decl == is_mod cov_decl) -- They import the same module
&& red_later -- Tie-break
+-}
where
red_loc = importSpecLoc red_imp
cov_loc = importSpecLoc cov_imp
red_later = red_loc > cov_loc
- cov_selective = selectiveImpItem cov_item
- red_selective = selectiveImpItem red_item
-
-selectiveImpItem :: ImpItemSpec -> Bool
-selectiveImpItem ImpAll = False
-selectiveImpItem (ImpSome {}) = True
-- ToDo: deal with original imports with 'qualified' and 'as M' clauses
printMinimalImports :: FiniteMap ModuleName AvailEnv -- Minimal imports
printMinimalImports imps
= ifOptM Opt_D_dump_minimal_imports $ do {
- mod_ies <- mappM to_ies (fmToList imps) ;
+ mod_ies <- initIfaceTcRn $ mappM to_ies (fmToList imps) ;
this_mod <- getModule ;
rdr_env <- getGlobalRdrEnv ;
+ dflags <- getDOpts ;
ioToTcRn (do { h <- openFile (mkFilename this_mod) WriteMode ;
- printForUser h (mkPrintUnqualified rdr_env)
+ printForUser h (mkPrintUnqualified dflags rdr_env)
(vcat (map ppr_mod_ie mod_ies)) })
}
where
to_ies (mod, avail_env) = do ies <- mapM to_ie (availEnvElts avail_env)
returnM (mod, ies)
- to_ie :: AvailInfo -> RnM (IE Name)
+ to_ie :: AvailInfo -> IfG (IE Name)
-- The main trick here is that if we're importing all the constructors
-- we want to say "T(..)", but if we're importing only a subset we want
-- to say "T(A,B,C)". So we have to find out what the module exports.
to_ie (AvailTC n [m]) = ASSERT( n==m )
returnM (IEThingAbs n)
to_ie (AvailTC n ns)
- = loadSrcInterface doc n_mod False `thenM` \ iface ->
+ = loadSysInterface doc n_mod `thenM` \ iface ->
case [xs | (m,as) <- mi_exports iface,
- moduleName m == n_mod,
+ m == n_mod,
AvailTC x xs <- as,
x == nameOccName n] of
[xs] | all_used xs -> returnM (IEThingAll n)
where
all_used avail_occs = all (`elem` map nameOccName ns) avail_occs
doc = text "Compute minimal imports from" <+> ppr n
- n_mod = moduleName (nameModule n)
+ n_mod = nameModule n
\end{code}
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") ]
+ ptext SLIT("suggests that") <+> quotes (ppr tc) <+> ptext SLIT("has constructors or class methods,"),
+ ptext SLIT("but it has none") ]
exportItemErr export_item
= sep [ ptext SLIT("The export item") <+> quotes (ppr export_item),
typeItemErr name wherestr
= sep [ ptext SLIT("Using 'type' tag on") <+> quotes (ppr name) <+> wherestr,
- ptext SLIT("Use -findexed-types to enable this extension") ]
+ ptext SLIT("Use -XTypeFamilies to enable this extension") ]
+exportClashErr :: GlobalRdrEnv -> Name -> Name -> IE RdrName -> IE RdrName
+ -> Message
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 ]
+ , ppr_export ie1' name1'
+ , ppr_export ie2' name2' ]
where
occ = nameOccName name1
ppr_export ie name = nest 2 (quotes (ppr ie) <+> ptext SLIT("exports") <+>
= case lookupGRE_Name global_env name of
(gre:_) -> gre
[] -> pprPanic "exportClashErr" (ppr name)
+ get_loc name = nameSrcLoc $ gre_name $ get_gre name
+ (name1', ie1', name2', ie2') = if get_loc name1 < get_loc name2
+ then (name1, ie1, name2, ie2)
+ else (name2, ie2, name1, ie1)
addDupDeclErr :: Name -> Name -> TcRn ()
addDupDeclErr name_a name_b
quotes (ptext SLIT("Module") <+> ppr mod),
ptext SLIT("in export list")]
+moduleNotImported :: ModuleName -> SDoc
+moduleNotImported mod
+ = ptext SLIT("The export item `module") <+> ppr mod <>
+ ptext SLIT("' is not imported")
+
nullModuleExport mod
= ptext SLIT("The export item `module") <+> ppr mod <> ptext SLIT("' exports nothing")
moduleDeprec mod txt
= sep [ ptext SLIT("Module") <+> quotes (ppr mod) <+> ptext SLIT("is deprecated:"),
nest 4 (ppr txt) ]
+
+implicitPreludeWarn
+ = ptext SLIT("Module `Prelude' implicitly imported")
\end{code}