X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Frename%2FRnBinds.lhs;h=876f25aeacd6c7d7cb0424b64dd2fd3374c52f9b;hb=6e9c0431a7cf2bf1a48f01db48c6a1d41fe15a09;hp=6ca3bdb8dd01a202b4b64354121374177cd62830;hpb=4385caba003064bb556f965b32fdc962ea19ea69;p=ghc-hetmet.git diff --git a/compiler/rename/RnBinds.lhs b/compiler/rename/RnBinds.lhs index 6ca3bdb..876f25a 100644 --- a/compiler/rename/RnBinds.lhs +++ b/compiler/rename/RnBinds.lhs @@ -22,13 +22,12 @@ import HsSyn import RdrHsSyn import RnHsSyn import TcRnMonad -import RnTypes ( rnHsSigType, rnLHsType, rnHsTypeFVs,checkPrecMatch) -import RnPat (rnPatsAndThen_LocalRightwards, rnBindPat, - NameMaker, localRecNameMaker, topRecNameMaker, applyNameMaker, - patSigErr) +import RnTypes ( rnHsSigType, rnLHsType, checkPrecMatch) +import RnPat (rnPats, rnBindPat, + NameMaker, localRecNameMaker, topRecNameMaker, applyNameMaker + ) import RnEnv -import PrelNames ( mkUnboundName ) import DynFlags ( DynFlag(..) ) import Name import NameEnv @@ -37,13 +36,13 @@ import RdrName ( RdrName, rdrNameOcc ) import SrcLoc import ListSetOps ( findDupsEq ) import BasicTypes ( RecFlag(..) ) -import Digraph ( SCC(..), stronglyConnComp ) +import Digraph ( SCC(..), stronglyConnCompFromEdgedVertices ) import Bag import Outputable import FastString import Data.List ( partition ) import Maybes ( orElse ) -import Monad ( foldM, unless ) +import Control.Monad \end{code} -- ToDo: Put the annotations into the monad, so that they arrive in the proper @@ -158,10 +157,11 @@ it expects the global environment to contain bindings for the binders rnTopBindsLHS :: MiniFixityEnv -> HsValBinds RdrName -> RnM (HsValBindsLR Name RdrName) -rnTopBindsLHS fix_env binds = - (uncurry $ rnValBindsLHSFromDoc (topRecNameMaker fix_env)) (bindersAndDoc binds) binds +rnTopBindsLHS fix_env binds + = do { mod <- getModule + ; rnValBindsLHSFromDoc (topRecNameMaker mod fix_env) binds } -rnTopBindsRHS :: [Name] -- the names bound by these binds +rnTopBindsRHS :: NameSet -- Names bound by these binds -> HsValBindsLR Name RdrName -> RnM (HsValBinds Name, DefUses) rnTopBindsRHS bound_names binds = @@ -170,18 +170,17 @@ rnTopBindsRHS bound_names binds = then rnTopBindsBoot binds else rnValBindsRHSGen (\x -> x) -- don't trim free vars bound_names binds } - --- wrapper if we don't need to do anything in between the left and right, +-- Wrapper if we don't need to do anything in between the left and right, -- or anything else in the scope of the left -- --- never used when there are fixity declarations +-- Never used when there are fixity declarations rnTopBinds :: HsValBinds RdrName -> RnM (HsValBinds Name, DefUses) rnTopBinds b = do nl <- rnTopBindsLHS emptyFsEnv b let bound_names = map unLoc (collectHsValBinders nl) - bindLocalNames bound_names $ rnTopBindsRHS bound_names nl + bindLocalNames bound_names $ rnTopBindsRHS (mkNameSet bound_names) nl rnTopBindsBoot :: HsValBindsLR Name RdrName -> RnM (HsValBinds Name, DefUses) @@ -241,63 +240,46 @@ rnIPBind (IPBind n expr) = do %************************************************************************ \begin{code} --- wrapper for local binds --- creates the documentation info and calls the helper below +-- Renaming local binding gropus +-- Does duplicate/shadow check rnValBindsLHS :: MiniFixityEnv -> HsValBinds RdrName - -> RnM (HsValBindsLR Name RdrName) -rnValBindsLHS fix_env binds = - let (boundNames,doc) = bindersAndDoc binds - in rnValBindsLHSFromDoc_Local boundNames doc fix_env binds - --- a helper used for local binds that does the duplicates check, --- just so we don't forget to do it somewhere -rnValBindsLHSFromDoc_Local :: [Located RdrName] -- RdrNames of the LHS (so we don't have to gather them twice) - -> SDoc -- doc string for dup names and shadowing - -> MiniFixityEnv - -> HsValBinds RdrName - -> RnM (HsValBindsLR Name RdrName) - -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. - 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. - -- The behavior is even different. For example, - -- import A(f) - -- f = ... - -- should not produce a shadowing warning (but it will produce - -- an ambiguity warning if you use f), but - -- import A(f) - -- g = let f = ... in f - -- should. - rnValBindsLHSFromDoc (localRecNameMaker fix_env) boundNames doc binds - -bindersAndDoc :: HsValBinds RdrName -> ([Located RdrName], SDoc) -bindersAndDoc binds = - let - -- the unrenamed bndrs for error checking and reporting - orig = collectHsValBinders binds - doc = text "In the binding group for:" <+> pprWithCommas ppr (map unLoc orig) - in - (orig, doc) + -> RnM ([Name], HsValBindsLR Name RdrName) +rnValBindsLHS 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. + -- + -- Note that we don't want to do this at the top level, since + -- sorting out duplicates and shadowing there happens elsewhere. + -- The behavior is even different. For example, + -- import A(f) + -- f = ... + -- should not produce a shadowing warning (but it will produce + -- an ambiguity warning if you use f), but + -- import A(f) + -- g = let f = ... in f + -- should. + ; binds' <- rnValBindsLHSFromDoc (localRecNameMaker fix_env) binds + ; let bound_names = map unLoc $ collectHsValBinders binds' + ; envs <- getRdrEnvs + ; checkDupAndShadowedNames envs bound_names + ; return (bound_names, binds') } -- renames the left-hand sides -- generic version used both at the top level and for local binds -- does some error checking, but not what gets done elsewhere at the top level rnValBindsLHSFromDoc :: NameMaker - -> [Located RdrName] -- RdrNames of the LHS (so we don't have to gather them twice) - -> SDoc -- doc string for dup names and shadowing -> HsValBinds RdrName -> RnM (HsValBindsLR Name RdrName) -rnValBindsLHSFromDoc topP _original_bndrs doc (ValBindsIn mbinds sigs) = do - -- rename the LHSes - mbinds' <- mapBagM (rnBindLHS topP doc) mbinds - return $ ValBindsIn mbinds' sigs -rnValBindsLHSFromDoc _ _ _ b = pprPanic "rnValBindsLHSFromDoc" (ppr b) +rnValBindsLHSFromDoc topP (ValBindsIn mbinds sigs) + = do { mbinds' <- mapBagM (rnBindLHS topP doc) mbinds + ; return $ ValBindsIn mbinds' sigs } + where + bndrs = collectHsBindBinders mbinds + doc = text "In the binding group for:" <+> pprWithCommas ppr bndrs + +rnValBindsLHSFromDoc _ b = pprPanic "rnValBindsLHSFromDoc" (ppr b) -- General version used both from the top-level and for local things -- Assumes the LHS vars are in scope @@ -306,21 +288,20 @@ rnValBindsLHSFromDoc _ _ _ b = pprPanic "rnValBindsLHSFromDoc" (ppr b) rnValBindsRHSGen :: (FreeVars -> FreeVars) -- for trimming free var sets -- The trimming function trims the free vars we attach to a -- binding so that it stays reasonably small - -> [Name] -- names bound by the LHSes + -> NameSet -- Names bound by the LHSes -> HsValBindsLR Name RdrName -> RnM (HsValBinds Name, DefUses) -rnValBindsRHSGen trim bound_names (ValBindsIn mbinds sigs) = do - -- rename the sigs - env <- getGblEnv - traceRn (ptext (sLit "Rename sigs") <+> ppr (tcg_rdr_env env)) - sigs' <- renameSigs (Just (mkNameSet bound_names)) okBindSig sigs - -- rename the RHSes - binds_w_dus <- mapBagM (rnBind (mkSigTvFn sigs') trim) mbinds - let (anal_binds, anal_dus) = depAnalBinds binds_w_dus - (valbind', valbind'_dus) = (ValBindsOut anal_binds sigs', - usesOnly (hsSigsFVs sigs') `plusDU` anal_dus) - return (valbind', valbind'_dus) +rnValBindsRHSGen trim bound_names (ValBindsIn mbinds sigs) + = do { -- rename the sigs + sigs' <- renameSigs (Just bound_names) okBindSig sigs + -- rename the RHSes + ; binds_w_dus <- mapBagM (rnBind (mkSigTvFn sigs') trim) mbinds + ; case depAnalBinds binds_w_dus of + (anal_binds, anal_dus) -> do + { let valbind' = ValBindsOut anal_binds sigs' + valbind'_dus = usesOnly (hsSigsFVs sigs') `plusDU` anal_dus + ; return (valbind', valbind'_dus) }} rnValBindsRHSGen _ _ b = pprPanic "rnValBindsRHSGen" (ppr b) @@ -330,12 +311,12 @@ rnValBindsRHSGen _ _ b = pprPanic "rnValBindsRHSGen" (ppr b) -- 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 -rnValBindsRHS :: [Name] -- names bound by the LHSes +rnValBindsRHS :: NameSet -- names bound by the LHSes -> HsValBindsLR Name RdrName -> RnM (HsValBinds Name, DefUses) rnValBindsRHS bound_names binds = rnValBindsRHSGen (\ fvs -> -- only keep the names the names from this group - intersectNameSet (mkNameSet bound_names) fvs) bound_names binds + intersectNameSet bound_names fvs) bound_names binds -- for local binds @@ -347,20 +328,17 @@ rnValBindsAndThen :: HsValBinds RdrName -> (HsValBinds Name -> RnM (result, FreeVars)) -> RnM (result, FreeVars) 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] + = 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 + ; (bound_names, new_lhs) <- rnValBindsLHS new_fixities binds -- ...and bring them (and their fixities) into scope ; bindLocalNamesFV_WithFixities bound_names new_fixities $ do { -- (C) Do the RHS and thing inside - (binds', dus) <- rnValBindsRHS bound_names new_lhs + (binds', dus) <- rnValBindsRHS (mkNameSet bound_names) new_lhs ; (result, result_fvs) <- thing_inside binds' -- Report unused bindings based on the (accurate) @@ -419,7 +397,7 @@ makeMiniFixityEnv decls = foldlM add_one emptyFsEnv decls Nothing -> return $ extendFsEnv env fs fix_item Just (L loc' _) -> do { setSrcSpan loc $ - addLocErr (L name_loc name) (dupFixityDecl loc') + addErrAt name_loc (dupFixityDecl loc' name) ; return env} } @@ -464,8 +442,7 @@ rnBindLHS name_maker _ (L loc (FunBind { fun_id = name@(L nameLoc _), fun_tick = fun_tick })) = setSrcSpan loc $ - do { (newname, _fvs) <- applyNameMaker name_maker name $ \ newname -> - return (newname, emptyFVs) + do { newname <- applyNameMaker name_maker name ; return (L loc (FunBind { fun_id = L nameLoc newname, fun_infix = inf, fun_matches = matches, @@ -494,11 +471,13 @@ rnBind _ trim (L loc (PatBind { pat_lhs = pat, ; (grhss', fvs) <- rnGRHSs PatBindRhs grhss -- No scoped type variables for pattern bindings + ; let fvs' = trim fvs - ; return (L loc (PatBind { pat_lhs = pat, + ; fvs' `seq` -- See Note [Free-variable space leak] + return (L loc (PatBind { pat_lhs = pat, pat_rhs = grhss', pat_rhs_ty = placeHolderType, - bind_fvs = trim fvs }), + bind_fvs = fvs' }), bndrs, pat_fvs `plusFV` fvs) } rnBind sig_fn @@ -516,20 +495,35 @@ rnBind sig_fn ; (matches', fvs) <- bindSigTyVarsFV (sig_fn plain_name) $ -- bindSigTyVars tests for Opt_ScopedTyVars rnMatchGroup (FunRhs plain_name inf) matches + ; let fvs' = trim fvs ; checkPrecMatch inf plain_name matches' - ; return (L loc (FunBind { fun_id = name, + ; fvs' `seq` -- See Note [Free-variable space leak] + return (L loc (FunBind { fun_id = name, fun_infix = inf, fun_matches = matches', - bind_fvs = trim fvs, + bind_fvs = fvs', fun_co_fn = idHsWrapper, fun_tick = Nothing }), [plain_name], fvs) } rnBind _ _ b = pprPanic "rnBind" (ppr b) - + +{- +Note [Free-variable space leak] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +We have + fvs' = trim fvs +and we seq fvs' before turning it as part of a record. + +The reason is that trim is sometimes something like + \xs -> intersectNameSet (mkNameSet bound_names) xs +and we don't want to retain the list bound_names. This showed up in +trac ticket #1136. +-} + --------------------- depAnalBinds :: Bag (LHsBind Name, [Name], Uses) -> ([(RecFlag, LHsBinds Name)], DefUses) @@ -538,7 +532,7 @@ depAnalBinds :: Bag (LHsBind Name, [Name], Uses) depAnalBinds binds_w_dus = (map get_binds sccs, map get_du sccs) where - sccs = stronglyConnComp edges + sccs = stronglyConnCompFromEdgedVertices edges keyd_nodes = bagToList binds_w_dus `zip` [0::Int ..] @@ -624,7 +618,7 @@ rnMethodBind :: Name rnMethodBind cls sig_fn gen_tyvars (L loc (FunBind { fun_id = name, fun_infix = inf, fun_matches = MatchGroup matches _ })) = setSrcSpan loc $ do - sel_name <- lookupInstDeclBndr cls name + sel_name <- wrapLocM (lookupInstDeclBndr cls) name let plain_name = unLoc sel_name -- We use the selector name as the binder @@ -655,8 +649,8 @@ 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 _ _ _ mbind@(L _ (PatBind _ _ _ _)) = do - addLocErr mbind methodBindErr +rnMethodBind _ _ _ (L loc bind@(PatBind {})) = do + addErrAt loc (methodBindErr bind) return (emptyBag, emptyFVs) rnMethodBind _ _ _ b = pprPanic "rnMethodBind" (ppr b) @@ -704,6 +698,8 @@ renameSigs mb_names ok_sig sigs renameSig :: Maybe NameSet -> Sig RdrName -> RnM (Sig Name) -- FixitySig is renamed elsewhere. +renameSig _ (IdSig x) + = return (IdSig x) -- Actually this never occurs renameSig mb_names sig@(TypeSig v ty) = do { new_v <- lookupSigOccRn mb_names sig v ; new_ty <- rnHsSigType (quotes (ppr v)) ty @@ -725,98 +721,44 @@ renameSig mb_names sig@(InlineSig v s) renameSig mb_names sig@(FixSig (FixitySig v f)) = do { new_v <- lookupSigOccRn mb_names sig v ; return (FixSig (FixitySig new_v f)) } - --- lookupSigOccRn is used for type signatures and pragmas --- Is this valid? --- module A --- import M( f ) --- f :: Int -> Int --- f x = x --- It's clear that the 'f' in the signature must refer to A.f --- The Haskell98 report does not stipulate this, but it will! --- So we must treat the 'f' in the signature in the same way --- as the binding occurrence of 'f', using lookupBndrRn --- --- However, consider this case: --- import M( f ) --- f :: Int -> Int --- g x = x --- We don't want to say 'f' is out of scope; instead, we want to --- return the imported 'f', so that later on the reanamer will --- correctly report "misplaced type sig". - -lookupSigOccRn :: Maybe NameSet -> Sig RdrName -> Located RdrName -> RnM (Located Name) -lookupSigOccRn mb_names sig (L loc v) - = do { mb_n <- lookupBndrRn_maybe v - ; case mb_n of { - Just n -> case mb_names of { - Nothing -> return (L loc n) ; - Just ns | n `elemNameSet` ns -> return (L loc n) - | otherwise -> bale_out_with local_msg } ; - - Nothing -> do - { mb_n <- lookupGreRn_maybe v - ; case mb_n of - Just _ -> bale_out_with import_msg - Nothing -> bale_out_with empty - } }} - where - bale_out_with msg - = do { addErr (sep [ ptext (sLit "The") <+> hsSigDoc sig - <+> ptext (sLit "for") <+> quotes (ppr v) - , nest 2 $ ptext (sLit "lacks an accompanying binding")] - $$ nest 2 msg) - ; return (L loc (mkUnboundName v)) } - - local_msg = parens $ ptext (sLit "The") <+> hsSigDoc sig <+> ptext (sLit "must be given where") - <+> quotes (ppr v) <+> ptext (sLit "is declared") - - import_msg = parens $ ptext (sLit "You cannot give a") <+> hsSigDoc sig - <+> ptext (sLit "an imported value") \end{code} -************************************************************************ -* * +%************************************************************************ +%* * \subsection{Match} -* * -************************************************************************ +%* * +%************************************************************************ \begin{code} rnMatchGroup :: HsMatchContext Name -> MatchGroup RdrName -> RnM (MatchGroup Name, FreeVars) -rnMatchGroup ctxt (MatchGroup ms _) = do - (new_ms, ms_fvs) <- mapFvRn (rnMatch ctxt) ms - return (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) rnMatch' :: HsMatchContext Name -> Match RdrName -> RnM (Match Name, FreeVars) -rnMatch' ctxt (Match pats maybe_rhs_sig grhss) - = - -- Deal with the rhs type signature - 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' -> do - (grhss', grhss_fvs) <- rnGRHSs ctxt grhss - - return (Match pats' maybe_rhs_sig' grhss', grhss_fvs `plusFV` ty_fvs) +rnMatch' ctxt match@(Match pats maybe_rhs_sig grhss) + = do { -- Result type signatures are no longer supported + case maybe_rhs_sig of + Nothing -> return () + Just (L loc ty) -> addErrAt loc (resSigErr ctxt match ty) + + -- Now the main event + -- note that there are no local ficity decls for matches + ; rnPats ctxt pats $ \ pats' -> do + { (grhss', grhss_fvs) <- rnGRHSs ctxt grhss + + ; return (Match pats' Nothing grhss', grhss_fvs) }} -- The bindPatSigTyVarsFV and rnPatsAndThen will remove the bound FVs - where - rhs_sig_tys = case maybe_rhs_sig of - Nothing -> [] - Just ty -> [ty] - doc_sig = text "In a result type-signature" + +resSigErr :: HsMatchContext Name -> Match RdrName -> HsType RdrName -> SDoc +resSigErr ctxt match ty + = vcat [ ptext (sLit "Illegal result type signature") <+> quotes (ppr ty) + , nest 2 $ ptext (sLit "Result signatures are no longer supported in pattern matches") + , pprMatchInCtxt ctxt match ] \end{code}