\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, finishDeprecations
+ reportUnusedNames, finishDeprecations,
) where
#include "HsVersions.h"
import DynFlags
import HsSyn ( IE(..), ieName, ImportDecl(..), LImportDecl,
- ForeignDecl(..), HsGroup(..), HsValBinds(..),
+ ForeignDecl(..), HsGroup(..), HsValBindsLR(..),
Sig(..), collectHsBindLocatedBinders, tyClDeclNames,
instDeclATs, isFamInstDecl,
LIE )
import Module
import Name
import NameEnv
+import UniqFM
import NameSet
import OccName
import HscTypes
import SrcLoc
import FiniteMap
import ErrUtils
-import BasicTypes ( DeprecTxt )
+import BasicTypes ( DeprecTxt, Fixity )
import DriverPhases ( isHsBoot )
import Util
import ListSetOps
-- warning for {- SOURCE -} ones that are unnecessary
= do this_mod <- getModule
implicit_prelude <- doptM Opt_ImplicitPrelude
- implicit_ndp <- doptM Opt_Vectorise
let prel_imports = mkPrelImports this_mod implicit_prelude imports
- ndp_imports = mkNDPImports implicit_ndp
(source, ordinary) = partition is_source_import imports
is_source_import (L _ (ImportDecl _ is_boot _ _ _)) = is_boot
when (notNull prel_imports) $ addWarn (implicitPreludeWarn)
)
- stuff1 <- mapM (rnImportDecl this_mod) (prel_imports
- ++ ndp_imports
- ++ ordinary)
+ stuff1 <- mapM (rnImportDecl this_mod) (prel_imports ++ ordinary)
stuff2 <- mapM (rnImportDecl this_mod) source
let (decls, rdr_env, imp_avails,hpc_usage) = combine (stuff1 ++ stuff2)
return (decls, rdr_env, imp_avails,hpc_usage)
loc = mkGeneralSrcSpan FSLIT("Implicit import declaration")
-mkNDPImports :: Bool -> [LImportDecl RdrName]
-mkNDPImports False = []
-mkNDPImports True = [ndpImportDecl]
- where
- ndpImportDecl
- = L loc $
- ImportDecl (L loc nDP_INTERFACE_NAME)
- False -- not a boot interface
- True -- qualified
- (Just nDP_BUILTIN) -- "as"
- Nothing -- no import list
-
- loc = mkGeneralSrcSpan FSLIT("Implicit import declaration")
-
rnImportDecl :: Module
-> LImportDecl RdrName
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,
* 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
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
| isFamInstDecl (unLoc tc_decl)
= do { main_name <- lookupFamInstDeclBndr mod main_rdr
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
-- 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,
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
typeItemErr name wherestr
= sep [ ptext SLIT("Using 'type' tag on") <+> quotes (ppr name) <+> wherestr,
- ptext SLIT("Use -ftype-families to enable this extension") ]
+ ptext SLIT("Use -XTypeFamilies to enable this extension") ]
exportClashErr :: GlobalRdrEnv -> Name -> Name -> IE RdrName -> IE RdrName
-> Message
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")