X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Frename%2FRnBinds.lhs;h=e7a781c6439f8e51e941fc95cb6311d7b311941a;hb=7502efdcd468b9a77385c5456481cf39f8eec79f;hp=0dbed29c63eb11259241d710bbd3dde3a78bd203;hpb=7f2909e06884a04199131407c12ba179d5886f46;p=ghc-hetmet.git diff --git a/compiler/rename/RnBinds.lhs b/compiler/rename/RnBinds.lhs index 0dbed29..e7a781c 100644 --- a/compiler/rename/RnBinds.lhs +++ b/compiler/rename/RnBinds.lhs @@ -44,13 +44,13 @@ import RnEnv ( lookupLocatedBndrRn, bindLocatedLocalsFV, bindLocalNames, bindLocalNamesFV, bindLocalNamesFV_WithFixities, bindLocatedLocalsRn, - checkDupNames, checkShadowing + checkDupAndShadowedRdrNames ) import DynFlags ( DynFlag(..) ) import HscTypes (FixItem(..)) import Name import NameEnv -import UniqFM +import LazyUniqFM import NameSet import PrelNames ( isUnboundName ) import RdrName ( RdrName, rdrNameOcc ) @@ -60,9 +60,10 @@ import BasicTypes ( RecFlag(..) ) import Digraph ( SCC(..), stronglyConnComp ) import Bag import Outputable +import FastString import Maybes ( orElse ) import Util ( filterOut ) -import Monad ( foldM ) +import Monad ( foldM, unless ) \end{code} -- ToDo: Put the annotations into the monad, so that they arrive in the proper @@ -235,19 +236,19 @@ rnLocalBindsAndThen (HsValBinds val_binds) thing_inside = rnValBindsAndThen val_binds $ \ val_binds' -> thing_inside (HsValBinds val_binds') -rnLocalBindsAndThen (HsIPBinds binds) thing_inside - = rnIPBinds binds `thenM` \ (binds',fv_binds) -> - thing_inside (HsIPBinds binds') `thenM` \ (thing, fvs_thing) -> - returnM (thing, fvs_thing `plusFV` fv_binds) +rnLocalBindsAndThen (HsIPBinds binds) thing_inside = do + (binds',fv_binds) <- rnIPBinds binds + (thing, fvs_thing) <- thing_inside (HsIPBinds binds') + return (thing, fvs_thing `plusFV` fv_binds) -rnIPBinds (IPBinds ip_binds _no_dict_binds) - = do { (ip_binds', fvs_s) <- mapAndUnzipM (wrapLocFstM rnIPBind) ip_binds - ; return (IPBinds ip_binds' emptyLHsBinds, plusFVs fvs_s) } +rnIPBinds (IPBinds ip_binds _no_dict_binds) = do + (ip_binds', fvs_s) <- mapAndUnzipM (wrapLocFstM rnIPBind) ip_binds + return (IPBinds ip_binds' emptyLHsBinds, plusFVs fvs_s) -rnIPBind (IPBind n expr) - = newIPNameRn n `thenM` \ name -> - rnLExpr expr `thenM` \ (expr',fvExpr) -> +rnIPBind (IPBind n expr) = do + name <- newIPNameRn n + (expr',fvExpr) <- rnLExpr expr return (IPBind name expr', fvExpr) \end{code} @@ -282,8 +283,7 @@ rnValBindsLHSFromDoc_Local boundNames doc fix_env binds = do -- Do error checking: we need to check for dups here because we -- don't don't bind all of the variables from the ValBinds at once -- with bindLocatedLocals any more. - checkDupNames doc boundNames - checkShadowing doc boundNames + checkDupAndShadowedRdrNames doc boundNames -- (Note that we don't want to do this at the top level, since -- sorting out duplicates and shadowing there happens elsewhere. @@ -314,8 +314,7 @@ rnValBindsLHSFromDoc :: NameMaker -> SDoc -- doc string for dup names and shadowing -> HsValBinds RdrName -> RnM (HsValBindsLR Name RdrName) -rnValBindsLHSFromDoc topP original_bndrs doc binds@(ValBindsIn mbinds sigs) - = do +rnValBindsLHSFromDoc topP original_bndrs doc binds@(ValBindsIn mbinds sigs) = do -- rename the LHSes mbinds' <- mapBagM (rnBindLHS topP doc) mbinds return $ ValBindsIn mbinds' sigs @@ -331,8 +330,8 @@ rnValBindsRHSGen :: (FreeVars -> FreeVars) -- for trimming free var sets -> HsValBindsLR Name RdrName -> RnM (HsValBinds Name, DefUses) -rnValBindsRHSGen trim bound_names binds@(ValBindsIn mbinds sigs) - = do -- rename the sigs +rnValBindsRHSGen trim bound_names binds@(ValBindsIn mbinds sigs) = do + -- rename the sigs sigs' <- rename_sigs sigs -- rename the RHSes binds_w_dus <- mapBagM (rnBind (mkSigTvFn sigs') trim) mbinds @@ -342,14 +341,14 @@ rnValBindsRHSGen trim bound_names binds@(ValBindsIn mbinds sigs) -- We do the check-sigs after renaming the bindings, -- so that we have convenient access to the binders check_sigs (okBindSig (duDefs anal_dus)) sigs' - returnM (valbind', valbind'_dus) + return (valbind', valbind'_dus) --- wrapper for local binds +-- Wrapper for local binds -- --- the *client* of this function is responsible for checking for unused binders; +-- The *client* of this function is responsible for checking for unused binders; -- it doesn't (and can't: we don't have the thing inside the binds) happen here -- --- the client is also responsible for bringing the fixities into scope +-- The client is also responsible for bringing the fixities into scope rnValBindsRHS :: [Name] -- names bound by the LHSes -> HsValBindsLR Name RdrName -> RnM (HsValBinds Name, DefUses) @@ -366,42 +365,53 @@ rnValBindsRHS bound_names binds = rnValBindsAndThen :: HsValBinds RdrName -> (HsValBinds Name -> RnM (result, FreeVars)) -> RnM (result, FreeVars) -rnValBindsAndThen binds@(ValBindsIn _ sigs) thing_inside = - let - (original_bndrs, doc) = bindersAndDoc binds +rnValBindsAndThen binds@(ValBindsIn _ sigs) thing_inside + = do { let (original_bndrs, doc) = bindersAndDoc binds + + -- (A) Create the local fixity environment + ; new_fixities <- makeMiniFixityEnv [L loc sig | L loc (FixSig sig) <- sigs] - in do - -- (A) create the local fixity environment - new_fixities <- makeMiniFixityEnv [L loc sig | L loc (FixSig sig) <- sigs] + -- (B) Rename the LHSes + ; new_lhs <- rnValBindsLHSFromDoc_Local original_bndrs doc new_fixities binds + ; let bound_names = map unLoc $ collectHsValBinders new_lhs - -- (B) rename the LHSes - new_lhs <- rnValBindsLHSFromDoc_Local original_bndrs doc new_fixities binds - let bound_names = map unLoc $ collectHsValBinders new_lhs + -- ...and bring them (and their fixities) into scope + ; bindLocalNamesFV_WithFixities bound_names new_fixities $ do - -- and bring them (and their fixities) into scope - bindLocalNamesFV_WithFixities bound_names new_fixities $ - warnUnusedLocalBinds bound_names $ do + { -- (C) Do the RHS and thing inside + (binds', dus) <- rnValBindsRHS bound_names new_lhs + ; (result, result_fvs) <- thing_inside binds' - -- (C) do the RHS and thing inside - (binds', dus) <- rnValBindsRHS bound_names new_lhs - (result, result_fvs) <- thing_inside binds' + -- Report unused bindings based on the (accurate) + -- findUses. E.g. + -- let x = x in 3 + -- should report 'x' unused + ; let real_uses = findUses dus result_fvs + ; warnUnusedLocalBinds bound_names real_uses - let - -- the variables used in the val binds are: - -- (1) the uses of the binds + ; let + -- The variables "used" in the val binds are: + -- (1) the uses of the binds (duUses) -- (2) the FVs of the thing-inside - all_uses = (duUses dus) `plusFV` result_fvs - -- duUses: It's important to return all the uses. Otherwise consider: + all_uses = duUses dus `plusFV` result_fvs + -- Note [Unused binding hack] + -- ~~~~~~~~~~~~~~~~~~~~~~~~~~ + -- Note that *in contrast* to the above reporting of + -- unused bindings, (1) above uses duUses to return *all* + -- the uses, even if the binding is unused. Otherwise consider: -- x = 3 -- y = let p = x in 'x' -- NB: p not used -- If we don't "see" the dependency of 'y' on 'x', we may put the -- bindings in the wrong order, and the type checker will complain -- that x isn't in scope + -- + -- But note that this means we won't report 'x' as unused, + -- whereas we would if we had { x = 3; p = x; y = 'x' } - return (result, - -- the bound names are pruned out of all_uses - -- by the bindLocalNamesFV call above - all_uses) + ; return (result, all_uses) }} + -- The bound names are pruned out of all_uses + -- by the bindLocalNamesFV call above + -- Process the fixity declarations, making a FastString -> (Located Fixity) map @@ -629,24 +639,24 @@ rnMethodBinds cls sig_fn gen_tyvars binds rnMethodBind cls sig_fn gen_tyvars (L loc (FunBind { fun_id = name, fun_infix = inf, fun_matches = MatchGroup matches _ })) - = setSrcSpan loc $ - lookupInstDeclBndr cls name `thenM` \ sel_name -> - let plain_name = unLoc sel_name in - -- We use the selector name as the binder - - bindSigTyVarsFV (sig_fn plain_name) $ - mapFvRn (rn_match plain_name) matches `thenM` \ (new_matches, fvs) -> - let - new_group = MatchGroup new_matches placeHolderType - in - checkPrecMatch inf plain_name new_group `thenM_` - returnM (unitBag (L loc (FunBind { - fun_id = sel_name, fun_infix = inf, - fun_matches = new_group, - bind_fvs = fvs, fun_co_fn = idHsWrapper, - fun_tick = Nothing })), - fvs `addOneFV` plain_name) - -- The 'fvs' field isn't used for method binds + = setSrcSpan loc $ do + sel_name <- lookupInstDeclBndr cls name + let plain_name = unLoc sel_name + -- We use the selector name as the binder + + bindSigTyVarsFV (sig_fn plain_name) $ do + (new_matches, fvs) <- mapFvRn (rn_match plain_name) matches + let + new_group = MatchGroup new_matches placeHolderType + + checkPrecMatch inf plain_name new_group + return (unitBag (L loc (FunBind { + fun_id = sel_name, fun_infix = inf, + fun_matches = new_group, + bind_fvs = fvs, fun_co_fn = idHsWrapper, + fun_tick = Nothing })), + fvs `addOneFV` plain_name) + -- The 'fvs' field isn't used for method binds where -- Truly gruesome; bring into scope the correct members of the generic -- type variables. See comments in RnSource.rnSourceDecl(ClassDecl) @@ -661,9 +671,9 @@ rnMethodBind cls sig_fn gen_tyvars (L loc (FunBind { fun_id = name, fun_infix = -- Can't handle method pattern-bindings which bind multiple methods. -rnMethodBind cls sig_fn gen_tyvars mbind@(L loc (PatBind other_pat _ _ _)) - = addLocErr mbind methodBindErr `thenM_` - returnM (emptyBag, emptyFVs) +rnMethodBind cls sig_fn gen_tyvars mbind@(L loc (PatBind other_pat _ _ _)) = do + addLocErr mbind methodBindErr + return (emptyBag, emptyFVs) \end{code} @@ -687,25 +697,24 @@ signatures. We'd only need this if we wanted to report unused tyvars. \begin{code} renameSigs :: (LSig Name -> Bool) -> [LSig RdrName] -> RnM [LSig Name] -- Renames the signatures and performs error checks -renameSigs ok_sig sigs +renameSigs ok_sig sigs = do { sigs' <- rename_sigs sigs ; check_sigs ok_sig sigs' ; return sigs' } ---------------------- rename_sigs :: [LSig RdrName] -> RnM [LSig Name] -rename_sigs sigs = mappM (wrapLocM renameSig) sigs +rename_sigs sigs = mapM (wrapLocM renameSig) sigs ---------------------- check_sigs :: (LSig Name -> Bool) -> [LSig Name] -> RnM () -- Used for class and instance decls, as well as regular bindings -check_sigs ok_sig sigs +check_sigs ok_sig sigs = do -- Check for (a) duplicate signatures - -- (b) signatures for things not in this group - = do { - traceRn (text "SIGS" <+> ppr sigs) - ; mappM_ unknownSigErr (filter (not . ok_sig) sigs') - ; mappM_ dupSigDeclErr (findDupsEq eqHsSig sigs') } + -- (b) signatures for things not in this group = do + traceRn (text "SIGS" <+> ppr sigs) + mapM_ unknownSigErr (filter (not . ok_sig) sigs') + mapM_ dupSigDeclErr (findDupsEq eqHsSig sigs') where -- Don't complain about an unbound name again sigs' = filterOut bad_name sigs @@ -724,27 +733,27 @@ check_sigs ok_sig sigs renameSig :: Sig RdrName -> RnM (Sig Name) -- FixitSig is renamed elsewhere. -renameSig (TypeSig v ty) - = lookupLocatedSigOccRn v `thenM` \ new_v -> - rnHsSigType (quotes (ppr v)) ty `thenM` \ new_ty -> - returnM (TypeSig new_v new_ty) - -renameSig (SpecInstSig ty) - = rnLHsType (text "A SPECIALISE instance pragma") ty `thenM` \ new_ty -> - returnM (SpecInstSig new_ty) - -renameSig (SpecSig v ty inl) - = lookupLocatedSigOccRn v `thenM` \ new_v -> - rnHsSigType (quotes (ppr v)) ty `thenM` \ new_ty -> - returnM (SpecSig new_v new_ty inl) - -renameSig (InlineSig v s) - = lookupLocatedSigOccRn v `thenM` \ new_v -> - returnM (InlineSig new_v s) - -renameSig (FixSig (FixitySig v f)) - = lookupLocatedSigOccRn v `thenM` \ new_v -> - returnM (FixSig (FixitySig new_v f)) +renameSig (TypeSig v ty) = do + new_v <- lookupLocatedSigOccRn v + new_ty <- rnHsSigType (quotes (ppr v)) ty + return (TypeSig new_v new_ty) + +renameSig (SpecInstSig ty) = do + new_ty <- rnLHsType (text "A SPECIALISE instance pragma") ty + return (SpecInstSig new_ty) + +renameSig (SpecSig v ty inl) = do + new_v <- lookupLocatedSigOccRn v + new_ty <- rnHsSigType (quotes (ppr v)) ty + return (SpecSig new_v new_ty inl) + +renameSig (InlineSig v s) = do + new_v <- lookupLocatedSigOccRn v + return (InlineSig new_v s) + +renameSig (FixSig (FixitySig v f)) = do + new_v <- lookupLocatedSigOccRn v + return (FixSig (FixitySig new_v f)) \end{code} @@ -756,9 +765,9 @@ renameSig (FixSig (FixitySig v f)) \begin{code} rnMatchGroup :: HsMatchContext Name -> MatchGroup RdrName -> RnM (MatchGroup Name, FreeVars) -rnMatchGroup ctxt (MatchGroup ms _) - = mapFvRn (rnMatch ctxt) ms `thenM` \ (new_ms, ms_fvs) -> - returnM (MatchGroup new_ms placeHolderType, ms_fvs) +rnMatchGroup ctxt (MatchGroup ms _) = do + (new_ms, ms_fvs) <- mapFvRn (rnMatch ctxt) ms + return (MatchGroup new_ms placeHolderType, ms_fvs) rnMatch :: HsMatchContext Name -> LMatch RdrName -> RnM (LMatch Name, FreeVars) rnMatch ctxt = wrapLocFstM (rnMatch' ctxt) @@ -766,22 +775,22 @@ rnMatch ctxt = wrapLocFstM (rnMatch' ctxt) rnMatch' ctxt match@(Match pats maybe_rhs_sig grhss) = -- Deal with the rhs type signature - bindPatSigTyVarsFV rhs_sig_tys $ - doptM Opt_PatternSignatures `thenM` \ opt_PatternSignatures -> - (case maybe_rhs_sig of - Nothing -> returnM (Nothing, emptyFVs) - Just ty | opt_PatternSignatures -> rnHsTypeFVs doc_sig ty `thenM` \ (ty', ty_fvs) -> - returnM (Just ty', ty_fvs) - | otherwise -> addLocErr ty patSigErr `thenM_` - returnM (Nothing, emptyFVs) - ) `thenM` \ (maybe_rhs_sig', ty_fvs) -> - - -- Now the main event + bindPatSigTyVarsFV rhs_sig_tys $ do + opt_PatternSignatures <- doptM Opt_PatternSignatures + (maybe_rhs_sig', ty_fvs) <- + case maybe_rhs_sig of + Nothing -> return (Nothing, emptyFVs) + Just ty | opt_PatternSignatures -> do (ty', ty_fvs) <- rnHsTypeFVs doc_sig ty + return (Just ty', ty_fvs) + | otherwise -> do addLocErr ty patSigErr + return (Nothing, emptyFVs) + + -- Now the main event -- note that there are no local ficity decls for matches - rnPatsAndThen_LocalRightwards ctxt pats $ \ pats' -> - rnGRHSs ctxt grhss `thenM` \ (grhss', grhss_fvs) -> + rnPatsAndThen_LocalRightwards ctxt pats $ \ pats' -> do + (grhss', grhss_fvs) <- rnGRHSs ctxt grhss - returnM (Match pats' maybe_rhs_sig' grhss', grhss_fvs `plusFV` ty_fvs) + return (Match pats' maybe_rhs_sig' grhss', grhss_fvs `plusFV` ty_fvs) -- The bindPatSigTyVarsFV and rnPatsAndThen will remove the bound FVs where rhs_sig_tys = case maybe_rhs_sig of @@ -801,9 +810,9 @@ rnMatch' ctxt match@(Match pats maybe_rhs_sig grhss) rnGRHSs :: HsMatchContext Name -> GRHSs RdrName -> RnM (GRHSs Name, FreeVars) rnGRHSs ctxt (GRHSs grhss binds) - = rnLocalBindsAndThen binds $ \ binds' -> - mapFvRn (rnGRHS ctxt) grhss `thenM` \ (grhss', fvGRHSs) -> - returnM (GRHSs grhss' binds', fvGRHSs) + = rnLocalBindsAndThen binds $ \ binds' -> do + (grhss', fvGRHSs) <- mapFvRn (rnGRHS ctxt) grhss + return (GRHSs grhss' binds', fvGRHSs) rnGRHS :: HsMatchContext Name -> LGRHS RdrName -> RnM (LGRHS Name, FreeVars) rnGRHS ctxt = wrapLocFstM (rnGRHS' ctxt) @@ -813,7 +822,7 @@ rnGRHS' ctxt (GRHS guards rhs) ; ((guards', rhs'), fvs) <- rnStmts (PatGuard ctxt) guards $ rnLExpr rhs - ; checkM (pattern_guards_allowed || is_standard_guard guards') + ; unless (pattern_guards_allowed || is_standard_guard guards') (addWarn (nonStdGuardErr guards')) ; return (GRHS guards' rhs', fvs) }