X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Fparser%2FRdrHsSyn.lhs;h=779b67b80c0f01fe3fa47276ed99240bc6309fcf;hp=9cc6c65258679f228e6c05f1b1a12a9852948d50;hb=432b9c9322181a3644083e3c19b7e240d90659e7;hpb=a9c123b7ae2620627037ca974b9908b1eead827e diff --git a/compiler/parser/RdrHsSyn.lhs b/compiler/parser/RdrHsSyn.lhs index 9cc6c65..779b67b 100644 --- a/compiler/parser/RdrHsSyn.lhs +++ b/compiler/parser/RdrHsSyn.lhs @@ -8,10 +8,11 @@ module RdrHsSyn ( extractHsTyRdrTyVars, extractHsRhoRdrTyVars, extractGenericPatTyVars, - mkHsOpApp, mkClassDecl, + mkHsOpApp, mkHsIntegral, mkHsFractional, mkHsIsString, mkHsDo, mkHsSplice, - mkTyData, mkPrefixCon, mkRecCon, mkInlineSpec, + mkClassDecl, mkTyData, mkTyFamily, mkTySynonym, + splitCon, mkInlineSpec, mkRecConstrOrUpdate, -- HsExp -> [HsFieldUpdate] -> P HsExp cvBindGroup, @@ -28,16 +29,16 @@ module RdrHsSyn ( -- -> (FastString, RdrName, RdrNameHsType) -- -> P RdrNameHsDecl mkExtName, -- RdrName -> CLabelString - mkGadtDecl, -- Located RdrName -> LHsType RdrName -> ConDecl RdrName + mkGadtDecl, -- [Located RdrName] -> LHsType RdrName -> ConDecl RdrName + mkSimpleConDecl, + mkDeprecatedGadtRecordDecl, -- Bunch of functions in the parser monad for -- checking and constructing values checkPrecP, -- Int -> P Int checkContext, -- HsType -> P HsContext checkPred, -- HsType -> P HsPred - checkTyClHdr, -- LHsContext RdrName -> LHsType RdrName -> P (LHsContext RdrName, Located RdrName, [LHsTyVarBndr RdrName], [LHsType RdrName]) checkTyVars, -- [LHsType RdrName] -> P () - checkSynHdr, -- LHsType RdrName -> P (Located RdrName, [LHsTyVarBndr RdrName], [LHsType RdrName]) checkKindSigs, -- [LTyClDecl RdrName] -> P () checkInstType, -- HsType -> P HsType checkDerivDecl, -- LDerivDecl RdrName -> P (LDerivDecl RdrName) @@ -48,22 +49,26 @@ module RdrHsSyn ( checkMDo, -- [Stmt] -> P [Stmt] checkValDef, -- (SrcLoc, HsExp, HsRhs, [HsDecl]) -> P HsDecl checkValSig, -- (SrcLoc, HsExp, HsRhs, [HsDecl]) -> P HsDecl - parseError, -- String -> Pa + parseError, + parseErrorSDoc, ) where -#include "HsVersions.h" - import HsSyn -- Lots of it +import Class ( FunDep ) +import TypeRep ( Kind ) import RdrName ( RdrName, isRdrTyVar, isRdrTc, mkUnqual, rdrNameOcc, isRdrDataCon, isUnqual, getRdrName, isQual, - setRdrNameSpace ) -import BasicTypes ( maxPrecedence, Activation, InlineSpec(..), alwaysInlineSpec, neverInlineSpec ) -import Lexer ( P, failSpanMsgP, extension, glaExtsEnabled, bangPatEnabled ) + setRdrNameSpace, showRdrName ) +import BasicTypes ( maxPrecedence, Activation, RuleMatchInfo, + InlinePragma(..), InlineSpec(..), + alwaysInlineSpec, neverInlineSpec ) +import Lexer ( P, failSpanMsgP, extension, standaloneDerivingEnabled, bangPatEnabled ) import TysWiredIn ( unitTyCon ) -import ForeignCall ( CCallConv, Safety, CCallTarget(..), CExportSpec(..), +import ForeignCall ( CCallConv(..), Safety, CCallTarget(..), CExportSpec(..), DNCallSpec(..), DNKind(..), CLabelString ) import OccName ( srcDataName, varName, isDataOcc, isTcOcc, occNameString ) +import PrelNames ( forall_tv_RDR ) import SrcLoc import OrdList ( OrdList, fromOL ) import Bag ( Bag, emptyBag, snocBag, consBag, foldrBag ) @@ -71,7 +76,8 @@ import Outputable import FastString import List ( isSuffixOf, nubBy ) -import Monad ( unless ) + +#include "HsVersions.h" \end{code} @@ -88,39 +94,49 @@ It's used when making the for-alls explicit. extractHsTyRdrTyVars :: LHsType RdrName -> [Located RdrName] extractHsTyRdrTyVars ty = nubBy eqLocated (extract_lty ty []) +extractHsTysRdrTyVars :: [LHsType RdrName] -> [Located RdrName] +extractHsTysRdrTyVars ty = nubBy eqLocated (extract_ltys ty []) + extractHsRhoRdrTyVars :: LHsContext RdrName -> LHsType RdrName -> [Located RdrName] -- This one takes the context and tau-part of a -- sigma type and returns their free type variables extractHsRhoRdrTyVars ctxt ty = nubBy eqLocated $ extract_lctxt ctxt (extract_lty ty []) +extract_lctxt :: Located [LHsPred RdrName] -> [Located RdrName] -> [Located RdrName] extract_lctxt ctxt acc = foldr (extract_pred . unLoc) acc (unLoc ctxt) -extract_pred (HsClassP cls tys) acc = foldr extract_lty acc tys +extract_pred :: HsPred RdrName -> [Located RdrName] -> [Located RdrName] +extract_pred (HsClassP _ tys) acc = extract_ltys tys acc extract_pred (HsEqualP ty1 ty2) acc = extract_lty ty1 (extract_lty ty2 acc) -extract_pred (HsIParam n ty ) acc = extract_lty ty acc +extract_pred (HsIParam _ ty ) acc = extract_lty ty acc +extract_ltys :: [LHsType RdrName] -> [Located RdrName] -> [Located RdrName] +extract_ltys tys acc = foldr extract_lty acc tys + +extract_lty :: LHsType RdrName -> [Located RdrName] -> [Located RdrName] extract_lty (L loc ty) acc = case ty of HsTyVar tv -> extract_tv loc tv acc HsBangTy _ ty -> extract_lty ty acc + HsRecTy flds -> foldr (extract_lty . cd_fld_type) acc flds HsAppTy ty1 ty2 -> extract_lty ty1 (extract_lty ty2 acc) HsListTy ty -> extract_lty ty acc HsPArrTy ty -> extract_lty ty acc - HsTupleTy _ tys -> foldr extract_lty acc tys + HsTupleTy _ tys -> extract_ltys tys acc HsFunTy ty1 ty2 -> extract_lty ty1 (extract_lty ty2 acc) HsPredTy p -> extract_pred p acc HsOpTy ty1 (L loc tv) ty2 -> extract_tv loc tv (extract_lty ty1 (extract_lty ty2 acc)) HsParTy ty -> extract_lty ty acc - HsNumTy num -> acc + HsNumTy _ -> acc HsSpliceTy _ -> acc -- Type splices mention no type variables - HsKindSig ty k -> extract_lty ty acc - HsForAllTy exp [] cx ty -> extract_lctxt cx (extract_lty ty acc) - HsForAllTy exp tvs cx ty -> acc ++ (filter ((`notElem` locals) . unLoc) $ + HsKindSig ty _ -> extract_lty ty acc + HsForAllTy _ [] cx ty -> extract_lctxt cx (extract_lty ty acc) + HsForAllTy _ tvs cx ty -> acc ++ (filter ((`notElem` locals) . unLoc) $ extract_lctxt cx (extract_lty ty [])) where locals = hsLTyVarNames tvs - HsDocTy ty doc -> extract_lty ty acc + HsDocTy ty _ -> extract_lty ty acc extract_tv :: SrcSpan -> RdrName -> [Located RdrName] -> [Located RdrName] extract_tv loc tv acc | isRdrTyVar tv = L loc tv : acc @@ -133,10 +149,10 @@ extractGenericPatTyVars binds = nubBy eqLocated (foldrBag get [] binds) where get (L _ (FunBind { fun_matches = MatchGroup ms _ })) acc = foldr (get_m.unLoc) acc ms - get other acc = acc + get _ acc = acc get_m (Match (L _ (TypePat ty) : _) _ _) acc = extract_lty ty acc - get_m other acc = acc + get_m _ acc = acc \end{code} @@ -157,19 +173,57 @@ Similarly for mkConDecl, mkClassOpSig and default-method names. *** See "THE NAMING STORY" in HsDecls **** \begin{code} -mkClassDecl (cxt, cname, tyvars) fds sigs mbinds ats docs - = ClassDecl { tcdCtxt = cxt, tcdLName = cname, tcdTyVars = tyvars, - tcdFDs = fds, - tcdSigs = sigs, - tcdMeths = mbinds, - tcdATs = ats, - tcdDocs = docs - } - -mkTyData new_or_data (context, tname, tyvars, typats) ksig data_cons maybe_deriv - = TyData { tcdND = new_or_data, tcdCtxt = context, tcdLName = tname, - tcdTyVars = tyvars, tcdTyPats = typats, tcdCons = data_cons, - tcdKindSig = ksig, tcdDerivs = maybe_deriv } +mkClassDecl :: SrcSpan + -> Located (LHsContext RdrName, LHsType RdrName) + -> Located [Located (FunDep RdrName)] + -> Located (OrdList (LHsDecl RdrName)) + -> P (LTyClDecl RdrName) + +mkClassDecl loc (L _ (cxt, tycl_hdr)) fds where_cls + = do { let (binds, sigs, ats, docs) = cvBindsAndSigs (unLoc where_cls) + ; (cls, tparams) <- checkTyClHdr tycl_hdr + ; tyvars <- checkTyVars tparams -- Only type vars allowed + ; checkKindSigs ats + ; return (L loc (ClassDecl { tcdCtxt = cxt, tcdLName = cls, tcdTyVars = tyvars, + tcdFDs = unLoc fds, tcdSigs = sigs, tcdMeths = binds, + tcdATs = ats, tcdDocs = docs })) } + +mkTyData :: SrcSpan + -> NewOrData + -> Bool -- True <=> data family instance + -> Located (LHsContext RdrName, LHsType RdrName) + -> Maybe Kind + -> [LConDecl RdrName] + -> Maybe [LHsType RdrName] + -> P (LTyClDecl RdrName) +mkTyData loc new_or_data is_family (L _ (cxt, tycl_hdr)) ksig data_cons maybe_deriv + = do { (tc, tparams) <- checkTyClHdr tycl_hdr + + ; (tyvars, typats) <- checkTParams is_family tparams + ; return (L loc (TyData { tcdND = new_or_data, tcdCtxt = cxt, tcdLName = tc, + tcdTyVars = tyvars, tcdTyPats = typats, + tcdCons = data_cons, + tcdKindSig = ksig, tcdDerivs = maybe_deriv })) } + +mkTySynonym :: SrcSpan + -> Bool -- True <=> type family instances + -> LHsType RdrName -- LHS + -> LHsType RdrName -- RHS + -> P (LTyClDecl RdrName) +mkTySynonym loc is_family lhs rhs + = do { (tc, tparams) <- checkTyClHdr lhs + ; (tyvars, typats) <- checkTParams is_family tparams + ; return (L loc (TySynonym tc tyvars typats rhs)) } + +mkTyFamily :: SrcSpan + -> FamilyFlavour + -> LHsType RdrName -- LHS + -> Maybe Kind -- Optional kind signature + -> P (LTyClDecl RdrName) +mkTyFamily loc flavour lhs ksig + = do { (tc, tparams) <- checkTyClHdr lhs + ; tyvars <- checkTyVars tparams + ; return (L loc (TyFamily flavour tc tyvars ksig)) } \end{code} %************************************************************************ @@ -198,8 +252,8 @@ cvTopDecls decls = go (fromOL decls) cvBindGroup :: OrdList (LHsDecl RdrName) -> HsValBinds RdrName cvBindGroup binding = case cvBindsAndSigs binding of - (mbs, sigs, [], _) -> -- list of type decls *always* empty - ValBindsIn mbs sigs + (mbs, sigs, tydecls, _) -> ASSERT( null tydecls ) + ValBindsIn mbs sigs cvBindsAndSigs :: OrdList (LHsDecl RdrName) -> (Bag (LHsBind RdrName), [LSig RdrName], [LTyClDecl RdrName], [LDocDecl RdrName]) @@ -209,15 +263,16 @@ cvBindsAndSigs :: OrdList (LHsDecl RdrName) cvBindsAndSigs fb = go (fromOL fb) where go [] = (emptyBag, [], [], []) - go (L l x@(SigD s) : ds) = (bs, L l s : ss, ts, docs) - where (bs, ss, ts, docs) = go ds - go (L l x@(ValD b) : ds) = (b' `consBag` bs, ss, ts, docs) - where (b', ds') = getMonoBind (L l b) ds - (bs, ss, ts, docs) = go ds' + go (L l (SigD s) : ds) = (bs, L l s : ss, ts, docs) + where (bs, ss, ts, docs) = go ds + go (L l (ValD b) : ds) = (b' `consBag` bs, ss, ts, docs) + where (b', ds') = getMonoBind (L l b) ds + (bs, ss, ts, docs) = go ds' go (L l (TyClD t): ds) = (bs, ss, L l t : ts, docs) - where (bs, ss, ts, docs) = go ds - go (L l (DocD d) : ds) = (bs, ss, ts, (L l d) : docs) - where (bs, ss, ts, docs) = go ds + where (bs, ss, ts, docs) = go ds + go (L l (DocD d) : ds) = (bs, ss, ts, (L l d) : docs) + where (bs, ss, ts, docs) = go ds + go (L _ d : _) = pprPanic "cvBindsAndSigs" (ppr d) ----------------------------------------------------------------------------- -- Group function bindings into equation groups @@ -237,8 +292,8 @@ getMonoBind :: LHsBind RdrName -> [LHsDecl RdrName] -- -- No AndMonoBinds or EmptyMonoBinds here; just single equations -getMonoBind (L loc1 bind@(FunBind { fun_id = fun_id1@(L _ f1), fun_infix = is_infix1, - fun_matches = MatchGroup mtchs1 _ })) binds +getMonoBind (L loc1 (FunBind { fun_id = fun_id1@(L _ f1), fun_infix = is_infix1, + fun_matches = MatchGroup mtchs1 _ })) binds | has_args mtchs1 = go is_infix1 mtchs1 loc1 binds [] where @@ -257,6 +312,8 @@ getMonoBind (L loc1 bind@(FunBind { fun_id = fun_id1@(L _ f1), fun_infix = is_in getMonoBind bind binds = (bind, binds) +has_args :: [LMatch RdrName] -> Bool +has_args [] = panic "RdrHsSyn:has_args" has_args ((L _ (Match args _ _)) : _) = not (null args) -- Don't group together FunBinds if they have -- no arguments. This is necessary now that variable bindings @@ -289,7 +346,7 @@ addl gp (L l d : ds) = add gp l d ds add :: HsGroup a -> SrcSpan -> HsDecl a -> [LHsDecl a] -> (HsGroup a, Maybe (SpliceDecl a, [LHsDecl a])) -add gp l (SpliceD e) ds = (gp, Just (e, ds)) +add gp _ (SpliceD e) ds = (gp, Just (e, ds)) -- Class declarations: pull out the fixity signatures to the top add gp@(HsGroup {hs_tyclds = ts, hs_fixds = fs}) @@ -319,16 +376,23 @@ add gp@(HsGroup {hs_defds = ts}) l (DefD d) ds = addl (gp { hs_defds = L l d : ts }) ds add gp@(HsGroup {hs_fords = ts}) l (ForD d) ds = addl (gp { hs_fords = L l d : ts }) ds -add gp@(HsGroup {hs_depds = ts}) l (DeprecD d) ds - = addl (gp { hs_depds = L l d : ts }) ds +add gp@(HsGroup {hs_warnds = ts}) l (WarningD d) ds + = addl (gp { hs_warnds = L l d : ts }) ds +add gp@(HsGroup {hs_annds = ts}) l (AnnD d) ds + = addl (gp { hs_annds = L l d : ts }) ds add gp@(HsGroup {hs_ruleds = ts}) l (RuleD d) ds = addl (gp { hs_ruleds = L l d : ts }) ds add gp l (DocD d) ds = addl (gp { hs_docs = (L l d) : (hs_docs gp) }) ds +add_bind :: LHsBind a -> HsValBinds a -> HsValBinds a add_bind b (ValBindsIn bs sigs) = ValBindsIn (bs `snocBag` b) sigs -add_sig s (ValBindsIn bs sigs) = ValBindsIn bs (s:sigs) +add_bind _ (ValBindsOut {}) = panic "RdrHsSyn:add_bind" + +add_sig :: LSig a -> HsValBinds a -> HsValBinds a +add_sig s (ValBindsIn bs sigs) = ValBindsIn bs (s:sigs) +add_sig _ (ValBindsOut {}) = panic "RdrHsSyn:add_sig" \end{code} %************************************************************************ @@ -340,37 +404,120 @@ add_sig s (ValBindsIn bs sigs) = ValBindsIn bs (s:sigs) \begin{code} ----------------------------------------------------------------------------- --- mkPrefixCon +-- splitCon -- When parsing data declarations, we sometimes inadvertently parse -- a constructor application as a type (eg. in data T a b = C a b `D` E a b) -- This function splits up the type application, adds any pending -- arguments, and converts the type constructor back into a data constructor. -mkPrefixCon :: LHsType RdrName -> [LBangType RdrName] - -> P (Located RdrName, HsConDetails RdrName (LBangType RdrName)) -mkPrefixCon ty tys - = split ty tys +splitCon :: LHsType RdrName + -> P (Located RdrName, HsConDeclDetails RdrName) +-- This gets given a "type" that should look like +-- C Int Bool +-- or C { x::Int, y::Bool } +-- and returns the pieces +splitCon ty + = split ty [] where split (L _ (HsAppTy t u)) ts = split t (u : ts) split (L l (HsTyVar tc)) ts = do data_con <- tyConToDataCon l tc - return (data_con, PrefixCon ts) - split (L l _) _ = parseError l "parse error in data/newtype declaration" + return (data_con, mk_rest ts) + split (L l _) _ = parseError l "parse error in data/newtype declaration" + + mk_rest [L _ (HsRecTy flds)] = RecCon flds + mk_rest ts = PrefixCon ts + +mkDeprecatedGadtRecordDecl :: SrcSpan + -> Located RdrName + -> [ConDeclField RdrName] + -> LHsType RdrName + -> P (LConDecl RdrName) +-- This one uses the deprecated syntax +-- C { x,y ::Int } :: T a b +-- We give it a RecCon details right away +mkDeprecatedGadtRecordDecl loc (L con_loc con) flds res_ty + = do { data_con <- tyConToDataCon con_loc con + ; return (L loc (ConDecl { con_old_rec = True + , con_name = data_con + , con_explicit = Implicit + , con_qvars = [] + , con_cxt = noLoc [] + , con_details = RecCon flds + , con_res = ResTyGADT res_ty + , con_doc = Nothing })) } + +mkSimpleConDecl :: Located RdrName -> [LHsTyVarBndr RdrName] + -> LHsContext RdrName -> HsConDeclDetails RdrName + -> ConDecl RdrName + +mkSimpleConDecl name qvars cxt details + = ConDecl { con_old_rec = False + , con_name = name + , con_explicit = Explicit + , con_qvars = qvars + , con_cxt = cxt + , con_details = details + , con_res = ResTyH98 + , con_doc = Nothing } -mkRecCon :: Located RdrName -> - [([Located RdrName], LBangType RdrName, Maybe (LHsDoc RdrName))] -> - P (Located RdrName, HsConDetails RdrName (LBangType RdrName)) -mkRecCon (L loc con) fields - = do data_con <- tyConToDataCon loc con - return (data_con, RecCon [ (HsRecField l t d) | (ls, t, d) <- fields, l <- ls ]) +mkGadtDecl :: [Located RdrName] + -> LHsType RdrName -- Always a HsForAllTy + -> [ConDecl RdrName] +-- We allow C,D :: ty +-- and expand it as if it had been +-- C :: ty; D :: ty +-- (Just like type signatures in general.) +mkGadtDecl names (L _ (HsForAllTy imp qvars cxt tau)) + = [mk_gadt_con name | name <- names] + where + (details, res_ty) -- See Note [Sorting out the result type] + = case tau of + L _ (HsFunTy (L _ (HsRecTy flds)) res_ty) -> (RecCon flds, res_ty) + _other -> (PrefixCon [], tau) + + mk_gadt_con name + = ConDecl { con_old_rec = False + , con_name = name + , con_explicit = imp + , con_qvars = qvars + , con_cxt = cxt + , con_details = details + , con_res = ResTyGADT res_ty + , con_doc = Nothing } +mkGadtDecl _ other_ty = pprPanic "mkGadtDecl" (ppr other_ty) tyConToDataCon :: SrcSpan -> RdrName -> P (Located RdrName) tyConToDataCon loc tc | isTcOcc (rdrNameOcc tc) = return (L loc (setRdrNameSpace tc srcDataName)) | otherwise - = parseError loc (showSDoc (text "Not a constructor:" <+> quotes (ppr tc))) + = parseErrorSDoc loc (msg $$ extra) + where + msg = text "Not a data constructor:" <+> quotes (ppr tc) + extra | tc == forall_tv_RDR + = text "Perhaps you intended to use -XExistentialQuantification" + | otherwise = empty +\end{code} +Note [Sorting out the result type] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +In a GADT declaration which is not a record, we put the whole constr +type into the ResTyGADT for now; the renamer will unravel it once it +has sorted out operator fixities. Consider for example + C :: a :*: b -> a :*: b -> a :+: b +Initially this type will parse as + a :*: (b -> (a :*: (b -> (a :+: b)))) + +so it's hard to split up the arguments until we've done the precedence +resolution (in the renamer) On the other hand, for a record + { x,y :: Int } -> a :*: b +there is no doubt. AND we need to sort records out so that +we can bring x,y into scope. So: + * For PrefixCon we keep all the args in the ResTyGADT + * For RecCon we do not + +\begin{code} ---------------------------------------------------------------------------- -- Various Syntactic Checks @@ -395,130 +542,69 @@ checkDictTy (L spn ty) = check ty [] check (HsParTy t) args = check (unLoc t) args check _ _ = parseError spn "Malformed instance header" +checkTParams :: Bool -- Type/data family + -> [LHsType RdrName] + -> P ([LHsTyVarBndr RdrName], Maybe [LHsType RdrName]) +-- checkTParams checks the type parameters of a data/newtype declaration +-- There are two cases: +-- +-- a) Vanilla data/newtype decl. In that case +-- - the type parameters should all be type variables +-- - they may have a kind annotation +-- +-- b) Family data/newtype decl. In that case +-- - The type parameters may be arbitrary types +-- - We find the type-varaible binders by find the +-- free type vars of those types +-- - We make them all kind-sig-free binders (UserTyVar) +-- If there are kind sigs in the type parameters, they +-- will fix the binder's kind when we kind-check the +-- type parameters +checkTParams is_family tparams + | not is_family -- Vanilla case (a) + = do { tyvars <- checkTyVars tparams + ; return (tyvars, Nothing) } + | otherwise -- Family case (b) + = do { let tyvars = [L l (UserTyVar tv) + | L l tv <- extractHsTysRdrTyVars tparams] + ; return (tyvars, Just tparams) } + +checkTyVars :: [LHsType RdrName] -> P [LHsTyVarBndr RdrName] -- Check whether the given list of type parameters are all type variables -- (possibly with a kind signature). If the second argument is `False', -- only type variables are allowed and we raise an error on encountering a -- non-variable; otherwise, we allow non-variable arguments and return the -- entire list of parameters. --- -checkTyVars :: [LHsType RdrName] -> P () -checkTyVars tparms = mapM_ chk tparms +checkTyVars tparms = mapM chk tparms where -- Check that the name space is correct! chk (L l (HsKindSig (L _ (HsTyVar tv)) k)) - | isRdrTyVar tv = return () + | isRdrTyVar tv = return (L l (KindedTyVar tv k)) chk (L l (HsTyVar tv)) - | isRdrTyVar tv = return () - chk (L l other) = + | isRdrTyVar tv = return (L l (UserTyVar tv)) + chk (L l _) = parseError l "Type found where type variable expected" --- Check whether the type arguments in a type synonym head are simply --- variables. If not, we have a type equation of a type function and return --- all patterns. If yes, we return 'Nothing' as the third component to --- indicate a vanilla type synonym. --- -checkSynHdr :: LHsType RdrName - -> Bool -- is type instance? - -> P (Located RdrName, -- head symbol - [LHsTyVarBndr RdrName], -- parameters - [LHsType RdrName]) -- type patterns -checkSynHdr ty isTyInst = - do { (_, tc, tvs, tparms) <- checkTyClHdr (noLoc []) ty - ; unless isTyInst $ checkTyVars tparms - ; return (tc, tvs, tparms) } - - +checkTyClHdr :: LHsType RdrName + -> P (Located RdrName, -- the head symbol (type or class name) + [LHsType RdrName]) -- parameters of head symbol -- Well-formedness check and decomposition of type and class heads. --- -checkTyClHdr :: LHsContext RdrName -> LHsType RdrName - -> P (LHsContext RdrName, -- the type context - Located RdrName, -- the head symbol (type or class name) - [LHsTyVarBndr RdrName], -- free variables of the non-context part - [LHsType RdrName]) -- parameters of head symbol --- The header of a type or class decl should look like --- (C a, D b) => T a b --- or T a b --- or a + b --- etc --- With associated types, we can also have non-variable parameters; ie, --- T Int [a] --- The unaltered parameter list is returned in the fourth component of the --- result. Eg, for --- T Int [a] --- we return --- ('()', 'T', ['a'], ['Int', '[a]']) -checkTyClHdr (L l cxt) ty - = do (tc, tvs, parms) <- gol ty [] - mapM_ chk_pred cxt - return (L l cxt, tc, tvs, parms) +-- Decomposes T ty1 .. tyn into (T, [ty1, ..., tyn]) +-- Int :*: Bool into (:*:, [Int, Bool]) +-- returning the pieces +checkTyClHdr ty + = goL ty [] where - gol (L l ty) acc = go l ty acc + goL (L l ty) acc = go l ty acc go l (HsTyVar tc) acc - | isRdrTc tc = do tvs <- extractTyVars acc - return (L l tc, tvs, acc) - go l (HsOpTy t1 ltc@(L _ tc) t2) acc - | isRdrTc tc = do tvs <- extractTyVars (t1:t2:acc) - return (ltc, tvs, acc) - go l (HsParTy ty) acc = gol ty acc - go l (HsAppTy t1 t2) acc = gol t1 (t2:acc) - go l other acc = - parseError l "Malformed head of type or class declaration" - - -- The predicates in a type or class decl must be class predicates or - -- equational constraints. They need not all have variable-only - -- arguments, even in Haskell 98. - -- E.g. class (Monad m, Monad (t m)) => MonadT t m - chk_pred (L l (HsClassP _ _)) = return () - chk_pred (L l (HsEqualP _ _)) = return () - chk_pred (L l _) - = parseError l "Malformed context in type or class declaration" - --- Extract the type variables of a list of type parameters. --- --- * Type arguments can be complex type terms (needed for associated type --- declarations). --- -extractTyVars :: [LHsType RdrName] -> P [LHsTyVarBndr RdrName] -extractTyVars tvs = collects [] tvs - where - -- Collect all variables (1st arg serves as an accumulator) - collect tvs (L l (HsForAllTy _ _ _ _)) = - parseError l "Forall type not allowed as type parameter" - collect tvs (L l (HsTyVar tv)) - | isRdrTyVar tv = return $ L l (UserTyVar tv) : tvs - | otherwise = return tvs - collect tvs (L l (HsBangTy _ _ )) = - parseError l "Bang-style type annotations not allowed as type parameter" - collect tvs (L l (HsAppTy t1 t2 )) = do - tvs' <- collect tvs t2 - collect tvs' t1 - collect tvs (L l (HsFunTy t1 t2 )) = do - tvs' <- collect tvs t2 - collect tvs' t1 - collect tvs (L l (HsListTy t )) = collect tvs t - collect tvs (L l (HsPArrTy t )) = collect tvs t - collect tvs (L l (HsTupleTy _ ts )) = collects tvs ts - collect tvs (L l (HsOpTy t1 _ t2 )) = do - tvs' <- collect tvs t2 - collect tvs' t1 - collect tvs (L l (HsParTy t )) = collect tvs t - collect tvs (L l (HsNumTy t )) = return tvs - collect tvs (L l (HsPredTy t )) = - parseError l "Predicate not allowed as type parameter" - collect tvs (L l (HsKindSig (L _ (HsTyVar tv)) k)) - | isRdrTyVar tv = - return $ L l (KindedTyVar tv k) : tvs - | otherwise = - parseError l "Kind signature only allowed for type variables" - collect tvs (L l (HsSpliceTy t )) = - parseError l "Splice not allowed as type parameter" - - -- Collect all variables of a list of types - collects tvs [] = return tvs - collects tvs (t:ts) = do - tvs' <- collects tvs ts - collect tvs' t + | isRdrTc tc = return (L l tc, acc) + + go _ (HsOpTy t1 ltc@(L _ tc) t2) acc + | isRdrTc tc = return (ltc, t1:t2:acc) + go _ (HsParTy ty) acc = goL ty acc + go _ (HsAppTy t1 t2) acc = goL t1 (t2:acc) + go l _ _ = parseError l "Malformed head of type or class declaration" -- Check that associated type declarations of a class are all kind signatures. -- @@ -577,9 +663,9 @@ checkPred (L spn ty) checkDerivDecl :: LDerivDecl RdrName -> P (LDerivDecl RdrName) checkDerivDecl d@(L loc _) = - do glaExtOn <- extension glaExtsEnabled - if glaExtOn then return d - else parseError loc "Illegal stand-alone deriving declaration (use -fglasgow-exts)" + do stDerivOn <- extension standaloneDerivingEnabled + if stDerivOn then return d + else parseError loc "Illegal stand-alone deriving declaration (use -XStandaloneDeriving)" --------------------------------------------------------------------------- -- Checking statements in a do-expression @@ -589,15 +675,18 @@ checkDerivDecl d@(L loc _) = -- (b) returns it separately -- same comments apply for mdo as well +checkDo, checkMDo :: SrcSpan -> [LStmt RdrName] -> P ([LStmt RdrName], LHsExpr RdrName) + checkDo = checkDoMDo "a " "'do'" checkMDo = checkDoMDo "an " "'mdo'" checkDoMDo :: String -> String -> SrcSpan -> [LStmt RdrName] -> P ([LStmt RdrName], LHsExpr RdrName) -checkDoMDo pre nm loc [] = parseError loc ("Empty " ++ nm ++ " construct") -checkDoMDo pre nm loc ss = do +checkDoMDo _ nm loc [] = parseError loc ("Empty " ++ nm ++ " construct") +checkDoMDo pre nm _ ss = do check ss where - check [L l (ExprStmt e _ _)] = return ([], e) + check [] = panic "RdrHsSyn:checkDoMDo" + check [L _ (ExprStmt e _ _)] = return ([], e) check [L l _] = parseError l ("The last statement in " ++ pre ++ nm ++ " construct must be an expression") check (s:ss) = do @@ -632,9 +721,10 @@ checkPat loc (L _ (HsApp f x)) args = do { x <- checkLPat x; checkPat loc f (x:args) } checkPat loc (L _ e) [] = do { p <- checkAPat loc e; return (L loc p) } -checkPat loc pat _some_args +checkPat loc _ _ = patFail loc +checkAPat :: SrcSpan -> HsExpr RdrName -> P (Pat RdrName) checkAPat loc e = case e of EWildPat -> return (WildPat placeHolderType) HsVar x | isQual x -> parseError loc ("Qualified variable in pattern: " @@ -645,7 +735,7 @@ checkAPat loc e = case e of -- Overloaded numeric patterns (e.g. f 0 x = x) -- Negation is recorded separately, so that the literal is zero or +ve -- NB. Negative *primitive* literals are already handled by the lexer - HsOverLit pos_lit -> return (mkNPat pos_lit Nothing) + HsOverLit pos_lit -> return (mkNPat pos_lit Nothing) NegApp (L _ (HsOverLit pos_lit)) _ -> return (mkNPat pos_lit (Just noSyntaxExpr)) @@ -653,57 +743,60 @@ checkAPat loc e = case e of | bang == bang_RDR -> do { bang_on <- extension bangPatEnabled ; if bang_on then checkLPat e >>= (return . BangPat) - else parseError loc "Illegal bang-pattern (use -fbang-patterns)" } + else parseError loc "Illegal bang-pattern (use -XBangPatterns)" } ELazyPat e -> checkLPat e >>= (return . LazyPat) EAsPat n e -> checkLPat e >>= (return . AsPat n) - ExprWithTySig e t -> checkLPat e >>= \e -> - -- Pattern signatures are parsed as sigtypes, - -- but they aren't explicit forall points. Hence - -- we have to remove the implicit forall here. - let t' = case t of - L _ (HsForAllTy Implicit _ (L _ []) ty) -> ty - other -> other - in - return (SigPatIn e t') + -- view pattern is well-formed if the pattern is + EViewPat expr patE -> checkLPat patE >>= (return . (\p -> ViewPat expr p placeHolderType)) + ExprWithTySig e t -> do e <- checkLPat e + -- Pattern signatures are parsed as sigtypes, + -- but they aren't explicit forall points. Hence + -- we have to remove the implicit forall here. + let t' = case t of + L _ (HsForAllTy Implicit _ (L _ []) ty) -> ty + other -> other + return (SigPatIn e t') -- n+k patterns OpApp (L nloc (HsVar n)) (L _ (HsVar plus)) _ - (L _ (HsOverLit lit@(HsIntegral _ _))) + (L _ (HsOverLit lit@(OverLit {ol_val = HsIntegral {}}))) | plus == plus_RDR -> return (mkNPlusKPat (L nloc n) lit) - OpApp l op fix r -> checkLPat l >>= \l -> - checkLPat r >>= \r -> - case op of - L cl (HsVar c) | isDataOcc (rdrNameOcc c) - -> return (ConPatIn (L cl c) (InfixCon l r)) - _ -> patFail loc + OpApp l op _fix r -> do l <- checkLPat l + r <- checkLPat r + case op of + L cl (HsVar c) | isDataOcc (rdrNameOcc c) + -> return (ConPatIn (L cl c) (InfixCon l r)) + _ -> patFail loc - HsPar e -> checkLPat e >>= (return . ParPat) - ExplicitList _ es -> mapM (\e -> checkLPat e) es >>= \ps -> - return (ListPat ps placeHolderType) - ExplicitPArr _ es -> mapM (\e -> checkLPat e) es >>= \ps -> - return (PArrPat ps placeHolderType) + HsPar e -> checkLPat e >>= (return . ParPat) + ExplicitList _ es -> do ps <- mapM checkLPat es + return (ListPat ps placeHolderType) + ExplicitPArr _ es -> do ps <- mapM checkLPat es + return (PArrPat ps placeHolderType) - ExplicitTuple es b -> mapM (\e -> checkLPat e) es >>= \ps -> - return (TuplePat ps b placeHolderType) + ExplicitTuple es b -> do ps <- mapM checkLPat es + return (TuplePat ps b placeHolderType) - RecordCon c _ (HsRecordBinds fs) -> mapM checkPatField fs >>= \fs -> - return (ConPatIn c (RecCon (map (uncurry mkRecField) fs))) + RecordCon c _ (HsRecFields fs dd) + -> do fs <- mapM checkPatField fs + return (ConPatIn c (RecCon (HsRecFields fs dd))) + HsQuasiQuoteE q -> return (QuasiQuotePat q) -- Generics HsType ty -> return (TypePat ty) _ -> patFail loc plus_RDR, bang_RDR :: RdrName -plus_RDR = mkUnqual varName FSLIT("+") -- Hack -bang_RDR = mkUnqual varName FSLIT("!") -- Hack +plus_RDR = mkUnqual varName (fsLit "+") -- Hack +bang_RDR = mkUnqual varName (fsLit "!") -- Hack -checkPatField :: (Located RdrName, LHsExpr RdrName) -> P (Located RdrName, LPat RdrName) -checkPatField (n,e) = do - p <- checkLPat e - return (n,p) +checkPatField :: HsRecField RdrName (LHsExpr RdrName) -> P (HsRecField RdrName (LPat RdrName)) +checkPatField fld = do { p <- checkLPat (hsRecFieldArg fld) + ; return (fld { hsRecFieldArg = p }) } +patFail :: SrcSpan -> P a patFail loc = parseError loc "Parse error in pattern" @@ -726,10 +819,17 @@ checkValDef lhs opt_sig grhss fun is_infix pats opt_sig grhss Nothing -> checkPatBind lhs grhss } +checkFunBind :: SrcSpan + -> Located RdrName + -> Bool + -> [LHsExpr RdrName] + -> Maybe (LHsType RdrName) + -> Located (GRHSs RdrName) + -> P (HsBind RdrName) checkFunBind lhs_loc fun is_infix pats opt_sig (L rhs_span grhss) | isQual (unLoc fun) - = parseError (getLoc fun) ("Qualified name in function definition: " ++ - showRdrName (unLoc fun)) + = parseErrorSDoc (getLoc fun) + (ptext (sLit "Qualified name in function definition:") <+> ppr (unLoc fun)) | otherwise = do ps <- checkPatterns pats let match_span = combineSrcSpans lhs_loc rhs_span @@ -743,6 +843,9 @@ makeFunBind fn is_infix ms = FunBind { fun_id = fn, fun_infix = is_infix, fun_matches = mkMatchGroup ms, fun_co_fn = idHsWrapper, bind_fvs = placeHolderNames, fun_tick = Nothing } +checkPatBind :: LHsExpr RdrName + -> Located (GRHSs RdrName) + -> P (HsBind RdrName) checkPatBind lhs (L _ grhss) = do { lhs <- checkPattern lhs ; return (PatBind lhs grhss placeHolderType placeHolderNames) } @@ -754,44 +857,27 @@ checkValSig checkValSig (L l (HsVar v)) ty | isUnqual v && not (isDataOcc (rdrNameOcc v)) = return (TypeSig (L l v) ty) -checkValSig (L l other) ty +checkValSig (L l _) _ = parseError l "Invalid type signature" - -mkGadtDecl :: Located RdrName - -> LHsType RdrName -- assuming HsType - -> ConDecl RdrName -mkGadtDecl name (L _ (HsForAllTy _ qvars cxt ty)) = mk_gadt_con name qvars cxt ty -mkGadtDecl name ty = mk_gadt_con name [] (noLoc []) ty - -mk_gadt_con name qvars cxt ty - = ConDecl { con_name = name - , con_explicit = Implicit - , con_qvars = qvars - , con_cxt = cxt - , con_details = PrefixCon [] - , con_res = ResTyGADT ty - , con_doc = Nothing } - -- NB: we put the whole constr type into the ResTyGADT for now; - -- the renamer will unravel it once it has sorted out - -- operator fixities - --- A variable binding is parsed as a FunBind. +\end{code} +\begin{code} -- The parser left-associates, so there should -- not be any OpApps inside the e's splitBang :: LHsExpr RdrName -> Maybe (LHsExpr RdrName, [LHsExpr RdrName]) -- Splits (f ! g a b) into (f, [(! g), a, b]) -splitBang (L loc (OpApp l_arg bang@(L loc' (HsVar op)) _ r_arg)) +splitBang (L loc (OpApp l_arg bang@(L _ (HsVar op)) _ r_arg)) | op == bang_RDR = Just (l_arg, L loc (SectionR bang arg1) : argns) where (arg1,argns) = split_bang r_arg [] split_bang (L _ (HsApp f e)) es = split_bang f (e:es) split_bang e es = (e,es) -splitBang other = Nothing +splitBang _ = Nothing isFunLhs :: LHsExpr RdrName -> P (Maybe (Located RdrName, Bool, [LHsExpr RdrName])) +-- A variable binding is parsed as a FunBind. -- Just (fun, is_infix, arg_pats) if e is a function LHS -- -- The whole LHS is parsed as a single expression. @@ -852,21 +938,26 @@ checkPrecP (L l i) mkRecConstrOrUpdate :: LHsExpr RdrName -> SrcSpan - -> HsRecordBinds RdrName + -> ([HsRecField RdrName (LHsExpr RdrName)], Bool) -> P (HsExpr RdrName) -mkRecConstrOrUpdate (L l (HsVar c)) loc fs | isRdrDataCon c - = return (RecordCon (L l c) noPostTcExpr fs) -mkRecConstrOrUpdate exp loc fs@(HsRecordBinds (_:_)) - = return (RecordUpd exp fs [] [] []) -mkRecConstrOrUpdate _ loc (HsRecordBinds []) - = parseError loc "Empty record update" +mkRecConstrOrUpdate (L l (HsVar c)) _ (fs,dd) | isRdrDataCon c + = return (RecordCon (L l c) noPostTcExpr (mk_rec_fields fs dd)) +mkRecConstrOrUpdate exp loc (fs,dd) + | null fs = parseError loc "Empty record update" + | otherwise = return (RecordUpd exp (mk_rec_fields fs dd) [] [] []) + +mk_rec_fields :: [HsRecField id arg] -> Bool -> HsRecFields id arg +mk_rec_fields fs False = HsRecFields { rec_flds = fs, rec_dotdot = Nothing } +mk_rec_fields fs True = HsRecFields { rec_flds = fs, rec_dotdot = Just (length fs) } -mkInlineSpec :: Maybe Activation -> Bool -> InlineSpec +mkInlineSpec :: Maybe Activation -> RuleMatchInfo -> Bool -> InlineSpec -- The Maybe is becuase the user can omit the activation spec (and usually does) -mkInlineSpec Nothing True = alwaysInlineSpec -- INLINE -mkInlineSpec Nothing False = neverInlineSpec -- NOINLINE -mkInlineSpec (Just act) inl = Inline act inl +mkInlineSpec Nothing match_info True = alwaysInlineSpec match_info + -- INLINE +mkInlineSpec Nothing match_info False = neverInlineSpec match_info + -- NOINLINE +mkInlineSpec (Just act) match_info inl = Inline (InlinePragma act match_info) inl ----------------------------------------------------------------------------- @@ -883,9 +974,14 @@ mkImport :: CallConv -> Safety -> (Located FastString, Located RdrName, LHsType RdrName) -> P (HsDecl RdrName) -mkImport (CCall cconv) safety (entity, v, ty) = do - importSpec <- parseCImport entity cconv safety v +mkImport (CCall cconv) safety (entity, v, ty) + | cconv == PrimCallConv = do + let funcTarget = CFunction (StaticTarget (unLoc entity)) + importSpec = CImport PrimCallConv safety nilFS funcTarget return (ForD (ForeignImport v ty importSpec)) + | otherwise = do + importSpec <- parseCImport entity cconv safety v + return (ForD (ForeignImport v ty importSpec)) mkImport (DNCall ) _ (entity, v, ty) = do spec <- parseDImport entity return $ ForD (ForeignImport v ty (DNImport spec)) @@ -900,10 +996,10 @@ parseCImport :: Located FastString -> P ForeignImport parseCImport (L loc entity) cconv safety v -- FIXME: we should allow white space around `dynamic' and `wrapper' -=chak - | entity == FSLIT ("dynamic") = - return $ CImport cconv safety nilFS nilFS (CFunction DynamicTarget) - | entity == FSLIT ("wrapper") = - return $ CImport cconv safety nilFS nilFS CWrapper + | entity == fsLit "dynamic" = + return $ CImport cconv safety nilFS (CFunction DynamicTarget) + | entity == fsLit "wrapper" = + return $ CImport cconv safety nilFS CWrapper | otherwise = parse0 (unpackFS entity) where -- using the static keyword? @@ -911,41 +1007,35 @@ parseCImport (L loc entity) cconv safety v parse0 ('s':'t':'a':'t':'i':'c':rest) = parse1 rest parse0 rest = parse1 rest -- check for header file name - parse1 "" = parse4 "" nilFS False nilFS + parse1 "" = parse4 "" nilFS False parse1 (' ':rest) = parse1 rest parse1 str@('&':_ ) = parse2 str nilFS - parse1 str@('[':_ ) = parse3 str nilFS False parse1 str | ".h" `isSuffixOf` first = parse2 rest (mkFastString first) - | otherwise = parse4 str nilFS False nilFS + | otherwise = parse4 str nilFS False where - (first, rest) = break (\c -> c == ' ' || c == '&' || c == '[') str + (first, rest) = break (\c -> c == ' ' || c == '&') str -- check for address operator (indicating a label import) - parse2 "" header = parse4 "" header False nilFS + parse2 "" header = parse4 "" header False parse2 (' ':rest) header = parse2 rest header - parse2 ('&':rest) header = parse3 rest header True - parse2 str@('[':_ ) header = parse3 str header False - parse2 str header = parse4 str header False nilFS - -- check for library object name - parse3 (' ':rest) header isLbl = parse3 rest header isLbl - parse3 ('[':rest) header isLbl = - case break (== ']') rest of - (lib, ']':rest) -> parse4 rest header isLbl (mkFastString lib) - _ -> parseError loc "Missing ']' in entity" - parse3 str header isLbl = parse4 str header isLbl nilFS + parse2 ('&':rest) header = parse3 rest header + parse2 str header = parse4 str header False + -- eat spaces after '&' + parse3 (' ':rest) header = parse3 rest header + parse3 str header = parse4 str header True -- check for name of C function - parse4 "" header isLbl lib = build (mkExtName (unLoc v)) header isLbl lib - parse4 (' ':rest) header isLbl lib = parse4 rest header isLbl lib - parse4 str header isLbl lib - | all (== ' ') rest = build (mkFastString first) header isLbl lib - | otherwise = parseError loc "Malformed entity string" + parse4 "" header isLbl = build (mkExtName (unLoc v)) header isLbl + parse4 (' ':rest) header isLbl = parse4 rest header isLbl + parse4 str header isLbl + | all (== ' ') rest = build (mkFastString first) header isLbl + | otherwise = parseError loc "Malformed entity string" where (first, rest) = break (== ' ') str -- - build cid header False lib = return $ - CImport cconv safety header lib (CFunction (StaticTarget cid)) - build cid header True lib = return $ - CImport cconv safety header lib (CLabel cid ) + build cid header False = return $ + CImport cconv safety header (CFunction (StaticTarget cid)) + build cid header True = return $ + CImport cconv safety header (CLabel cid ) -- -- Unravel a dotnet spec string. @@ -970,8 +1060,9 @@ parseDImport (L loc entity) = parse0 comps parse2 _ _ [] = d'oh parse2 isStatic kind (('[':x):xs) = case x of - [] -> d'oh - vs | last vs == ']' -> parse3 isStatic kind (init vs) xs + [] -> d'oh + vs | last vs == ']' -> parse3 isStatic kind (init vs) xs + _ -> d'oh parse2 isStatic kind xs = parse3 isStatic kind "" xs parse3 isStatic kind assem [x] = @@ -988,12 +1079,12 @@ parseDImport (L loc entity) = parse0 comps mkExport :: CallConv -> (Located FastString, Located RdrName, LHsType RdrName) -> P (HsDecl RdrName) -mkExport (CCall cconv) (L loc entity, v, ty) = return $ +mkExport (CCall cconv) (L _ entity, v, ty) = return $ ForD (ForeignExport v ty (CExport (CExportStatic entity' cconv))) where entity' | nullFS entity = mkExtName (unLoc v) | otherwise = entity -mkExport DNCall (L loc entity, v, ty) = +mkExport DNCall (L _ _, v, _) = parseError (getLoc v){-TODO: not quite right-} "Foreign export is not yet supported for .NET" @@ -1012,9 +1103,9 @@ mkExtName rdrNm = mkFastString (occNameString (rdrNameOcc rdrNm)) -- Misc utils \begin{code} -showRdrName :: RdrName -> String -showRdrName r = showSDoc (ppr r) - parseError :: SrcSpan -> String -> P a -parseError span s = failSpanMsgP span s +parseError span s = parseErrorSDoc span (text s) + +parseErrorSDoc :: SrcSpan -> SDoc -> P a +parseErrorSDoc span s = failSpanMsgP span s \end{code}