X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Frename%2FRnNames.lhs;h=e5cd74102854ec566fc95da64f0b37dffccf542e;hb=459870b70715b066aadd6a9defc87fb1ffb45bf4;hp=ed3efd2382892dc8564a50eb9259ebc80800ac98;hpb=80ef1f06253f1a20a63816c295e180e47cd9a347;p=ghc-hetmet.git diff --git a/compiler/rename/RnNames.lhs b/compiler/rename/RnNames.lhs index ed3efd2..e5cd741 100644 --- a/compiler/rename/RnNames.lhs +++ b/compiler/rename/RnNames.lhs @@ -12,9 +12,8 @@ -- for details module RnNames ( - rnImports, importsFromLocalDecls, - rnExports, - getLocalDeclBinders, extendRdrEnvRn, + rnImports, getLocalNonValBinders, + rnExports, extendGlobalRdrEnvRn, reportUnusedNames, finishDeprecations, ) where @@ -36,7 +35,7 @@ import PrelNames import Module import Name import NameEnv -import UniqFM +import LazyUniqFM import NameSet import OccName import HscTypes @@ -49,6 +48,7 @@ import ErrUtils import BasicTypes ( DeprecTxt, Fixity ) import DriverPhases ( isHsBoot ) import Util +import FastString import ListSetOps import Data.List ( partition, concatMap, (\\), delete ) import IO ( openFile, IOMode(..) ) @@ -274,82 +274,71 @@ From the top-level declarations of this module produce * the ImportAvails created by its bindings. -\begin{code} --- 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 +Note [Shadowing in extendGlobalRdrEnvRn] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Usually when etending the GlobalRdrEnv we complain if a new binding +duplicates an existing one. By adding the bindings one at a time, +this check also complains if we add two new bindings for the same name. +(Remember that in Template Haskell the duplicates might *already be* +in the GlobalRdrEnv from higher up the module.) + +But with a Template Haskell quotation we want to *shadow*: + f x = h [d| f = 3 |] +Here the inner binding for 'f' simply shadows the outer one. +And that applies even if the binding for 'f' is in a where-clause, +and hence is in the *local* RdrEnv not the *global* RdrEnv. + +Hence the shadowP boolean passed in. - ; (rdr_env', fix_env') <- extendRdrEnvRn shadowP (tcg_rdr_env gbl_env, - tcg_fix_env gbl_env) - avails fixities +\begin{code} +extendGlobalRdrEnvRn :: Bool -- Note [Shadowing in extendGlobalRdrEnvRn] + -> [AvailInfo] + -> MiniFixityEnv + -> RnM (TcGblEnv, TcLclEnv) + -- Updates both the GlobalRdrEnv and the FixityEnv + -- We return a new TcLclEnv only becuase we might have to + -- delete some bindings from it; see Note [Shadowing in extendGlobalRdrEnvRn] + +extendGlobalRdrEnvRn shadowP avails new_fixities + = do { (gbl_env, lcl_env) <- getEnvs + ; let rdr_env = tcg_rdr_env gbl_env + fix_env = tcg_fix_env gbl_env + + -- Delete new_occs from global and local envs + -- We are going to shadow them + -- See Note [Shadowing in extendGlobalRdrEnvRn] + new_occs = map (nameOccName . gre_name) gres + rdr_env1 = hideSomeUnquals rdr_env new_occs + lcl_env1 = lcl_env { tcl_rdr = delListFromOccEnv (tcl_rdr lcl_env) new_occs } + + -- Note [Shadowing in extendGlobalRdrEnvRn] + (rdr_env2, lcl_env2) | shadowP = (rdr_env1, lcl_env1) + | otherwise = (rdr_env, lcl_env) - ; traceRn (text "local avails: " <> ppr avails) + ; (rdr_env', fix_env') <- foldlM extend (rdr_env2, fix_env) gres + + ; let gbl_env' = gbl_env { tcg_rdr_env = rdr_env', tcg_fix_env = fix_env' } + ; traceRn (text "extendGlobalRdrEnvRn" <+> (ppr new_fixities $$ ppr fix_env $$ ppr fix_env')) + ; return (gbl_env', lcl_env2) } + where + gres = gresFromAvails LocalDef avails - ; return (gbl_env { tcg_rdr_env = rdr_env', - tcg_fix_env = fix_env'}) - } + extend envs@(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 envs } + [] -> return (simple_extend envs gre) --- 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. --- --- 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) + simple_extend (rdr_env, fix_env) gre + = (extendGlobalRdrEnv rdr_env gre, fix_env') + where + -- If there is a fixity decl for the gre, add it to the fixity env + name = gre_name gre + occ = nameOccName name + fix_env' = case lookupFsEnv new_fixities (occNameFS occ) of + Nothing -> fix_env + Just (L _ fi) -> extendNameEnv fix_env name (FixItem occ fi) \end{code} @getLocalDeclBinders@ returns the names for an @HsDecl@. It's @@ -369,13 +358,24 @@ raising a duplicate declaration error. So, we make a new name for it, but 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 }) +getLocalNonValBinders :: HsGroup RdrName -> RnM [AvailInfo] +-- Get all the top-level binders bound the group *except* +-- for value bindings, which are treated separately +-- Specificaly we return AvailInfo for +-- type decls +-- class decls +-- associated types +-- foreign imports +-- (in hs-boot files) value signatures + +getLocalNonValBinders group + = do { gbl_env <- getGblEnv + ; get_local_binders gbl_env group } + +get_local_binders gbl_env (HsGroup {hs_valds = ValBindsIn _ val_sigs, + hs_tyclds = tycl_decls, + hs_instds = inst_decls, + hs_fords = foreign_decls }) = do { tc_names_s <- mapM new_tc tycl_decls ; at_names_s <- mapM inst_ats inst_decls ; val_names <- mapM new_simple val_bndrs @@ -1263,7 +1263,7 @@ warnDuplicateImports gres -- -- NOTE: currently the test does not warn about -- import M( x ) - -- imoprt N( x ) + -- import N( x ) -- even if the same underlying 'x' is involved, because dropping -- either import would change the qualified names in scope (M.x, N.x) -- But if the qualified names aren't used, the import is indeed redundant