\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(..),
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
\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
*** 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
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
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
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
-- 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
+ -- BUG WARNING: this code is generally buggy
unused_imp_mods :: [(ModuleName, SrcSpan)]
- unused_imp_mods = [(mod_name,loc) | (mod,no_imp,loc) <- direct_import_mods,
+ 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,
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 ;
ioToTcRn (do { h <- openFile (mkFilename this_mod) WriteMode ;
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 -ftype-families 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}