X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnSource.lhs;h=6ee9f8a7dd9c7afebb534daf299726289b0a153c;hb=a8eecb891f9ca609b1ca96dee520124b00ece40f;hp=1b19d4b69ff7cfd9bb1ded963872110cefa5dd20;hpb=77a8c0dbd5c5ad90fe483cb9ddc2b6ef36d3f4d8;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnSource.lhs b/ghc/compiler/rename/RnSource.lhs index 1b19d4b..6ee9f8a 100644 --- a/ghc/compiler/rename/RnSource.lhs +++ b/ghc/compiler/rename/RnSource.lhs @@ -4,63 +4,49 @@ \section[RnSource]{Main pass of renamer} \begin{code} -module RnSource ( rnDecl, rnSourceDecls, rnHsType, rnHsSigType ) where +module RnSource ( + rnSrcDecls, addTcgDUs, + rnTyClDecls, checkModDeprec, + rnBindGroups, rnBindGroupsAndThen, rnSplice + ) where #include "HsVersions.h" -import RnExpr import HsSyn -import HsPragmas -import HsTypes ( hsTyVarNames, pprHsContext ) -import RdrName ( RdrName, isRdrDataCon, rdrNameOcc, isRdrTyVar, mkRdrNameWkr ) -import RdrHsSyn ( RdrNameContext, RdrNameHsType, RdrNameConDecl, - extractRuleBndrsTyVars, extractHsTyRdrTyVars, - extractHsTysRdrTyVars, extractHsCtxtRdrTyVars - ) +import RdrName ( RdrName, isRdrDataCon, rdrNameOcc, elemLocalRdrEnv ) +import RdrHsSyn ( extractGenericPatTyVars ) import RnHsSyn -import HsCore - -import RnBinds ( rnTopBinds, rnMethodBinds, renameSigs, unknownSigErr ) -import RnEnv ( bindTyVarsRn, lookupBndrRn, lookupOccRn, getIPName, - lookupImplicitOccRn, lookupImplicitOccsRn, - bindLocalsRn, bindLocalRn, bindLocalsFVRn, bindUVarRn, - bindTyVarsFVRn, bindTyVarsFV2Rn, extendTyVarEnvFVRn, - bindCoreLocalFVRn, bindCoreLocalsFVRn, - checkDupOrQualNames, checkDupNames, - mkImportedGlobalName, mkImportedGlobalFromRdrName, - newDFunName, getDFunKey, newImplicitBinder, - FreeVars, emptyFVs, plusFV, plusFVs, unitFV, - addOneFV, mapFvRn +import RnExpr ( rnLExpr, checkTH ) +import RnTypes ( rnLHsType, rnLHsTypes, rnHsSigType, rnHsTypeFVs, rnContext ) +import RnBinds ( rnTopBinds, rnBinds, rnMethodBinds, + rnBindsAndThen, renameSigs, checkSigs ) +import RnEnv ( lookupTopBndrRn, lookupTopFixSigNames, + lookupLocatedTopBndrRn, lookupLocatedOccRn, + lookupOccRn, newLocalsRn, + bindLocatedLocalsFV, bindPatSigTyVarsFV, + bindTyVarsRn, extendTyVarEnvFVRn, + bindLocalNames, newIPNameRn, + checkDupNames, mapFvRn, + unknownNameErr ) -import RnMonad +import TcRnMonad -import FunDeps ( oclose ) +import BasicTypes ( TopLevelFlag(..) ) +import HscTypes ( FixityEnv, FixItem(..), + Deprecations, Deprecs(..), DeprecTxt, plusDeprecs ) import Class ( FunDep ) - -import Name ( Name, OccName, - ExportFlag(..), Provenance(..), - nameOccName, NamedThing(..) - ) +import Name ( Name, nameOccName ) import NameSet -import OccName ( mkDefaultMethodOcc ) -import FiniteMap ( elemFM ) -import PrelInfo ( derivableClassKeys, cCallishClassKeys, - deRefStablePtr_RDR, makeStablePtr_RDR, - bindIO_RDR, returnIO_RDR - ) -import Bag ( bagToList ) -import List ( partition, nub ) +import NameEnv import Outputable -import SrcLoc ( SrcLoc ) -import CmdLineOpts ( opt_GlasgowExts, opt_WarnUnusedMatches ) -- Warn of unused for-all'd tyvars -import Unique ( Uniquable(..) ) -import ErrUtils ( Message ) -import CStrings ( isCLabelString ) -import Maybes ( maybeToBool, catMaybes ) -import Util +import SrcLoc ( Located(..), unLoc, getLoc, noLoc ) +import CmdLineOpts ( DynFlag(..) ) + -- Warn of unused for-all'd tyvars +import Maybes ( seqMaybe ) +import Maybe ( catMaybes, isNothing ) \end{code} -@rnDecl@ `renames' declarations. +@rnSourceDecl@ `renames' declarations. It simultaneously performs dependency analysis and precedence parsing. It also does the following error checks: \begin{enumerate} @@ -76,307 +62,317 @@ Checks the @(..)@ etc constraints in the export list. \end{enumerate} +\begin{code} +rnSrcDecls :: HsGroup RdrName -> RnM (TcGblEnv, HsGroup Name) + +rnSrcDecls (HsGroup { hs_valds = [HsBindGroup binds sigs _], + hs_tyclds = tycl_decls, + hs_instds = inst_decls, + hs_fixds = fix_decls, + hs_depds = deprec_decls, + hs_fords = foreign_decls, + hs_defds = default_decls, + hs_ruleds = rule_decls }) + + = do { -- Deal with deprecations (returns only the extra deprecations) + deprecs <- rnSrcDeprecDecls deprec_decls ; + updGblEnv (\gbl -> gbl { tcg_deprecs = tcg_deprecs gbl `plusDeprecs` deprecs }) + $ do { + + -- Deal with top-level fixity decls + -- (returns the total new fixity env) + fix_env <- rnSrcFixityDecls fix_decls ; + updGblEnv (\gbl -> gbl { tcg_fix_env = fix_env }) + $ do { + + -- Rename other declarations + traceRn (text "Start rnmono") ; + (rn_val_decls, bind_dus) <- rnTopBinds binds sigs ; + traceRn (text "finish rnmono" <+> ppr rn_val_decls) ; + + -- You might think that we could build proper def/use information + -- for type and class declarations, but they can be involved + -- in mutual recursion across modules, and we only do the SCC + -- analysis for them in the type checker. + -- So we content ourselves with gathering uses only; that + -- means we'll only report a declaration as unused if it isn't + -- mentioned at all. Ah well. + (rn_tycl_decls, src_fvs1) + <- mapFvRn (wrapLocFstM rnTyClDecl) tycl_decls ; + (rn_inst_decls, src_fvs2) + <- mapFvRn (wrapLocFstM rnSrcInstDecl) inst_decls ; + (rn_rule_decls, src_fvs3) + <- mapFvRn (wrapLocFstM rnHsRuleDecl) rule_decls ; + (rn_foreign_decls, src_fvs4) + <- mapFvRn (wrapLocFstM rnHsForeignDecl) foreign_decls ; + (rn_default_decls, src_fvs5) + <- mapFvRn (wrapLocFstM rnDefaultDecl) default_decls ; + + let { + rn_group = HsGroup { hs_valds = rn_val_decls, + hs_tyclds = rn_tycl_decls, + hs_instds = rn_inst_decls, + hs_fixds = [], + hs_depds = [], + hs_fords = rn_foreign_decls, + hs_defds = rn_default_decls, + hs_ruleds = rn_rule_decls } ; + + other_fvs = plusFVs [src_fvs1, src_fvs2, src_fvs3, + src_fvs4, src_fvs5] ; + src_dus = bind_dus `plusDU` usesOnly other_fvs + -- Note: src_dus will contain *uses* for locally-defined types + -- and classes, but no *defs* for them. (Because rnTyClDecl + -- returns only the uses.) This is a little + -- surprising but it doesn't actually matter at all. + } ; + + traceRn (text "finish rnSrc" <+> ppr rn_group) ; + traceRn (text "finish Dus" <+> ppr src_dus ) ; + tcg_env <- getGblEnv ; + return (tcg_env `addTcgDUs` src_dus, rn_group) + }}} + +rnTyClDecls :: [LTyClDecl RdrName] -> RnM [LTyClDecl Name] +rnTyClDecls tycl_decls = do + (decls', fvs) <- mapFvRn (wrapLocFstM rnTyClDecl) tycl_decls + return decls' + +addTcgDUs :: TcGblEnv -> DefUses -> TcGblEnv +addTcgDUs tcg_env dus = tcg_env { tcg_dus = tcg_dus tcg_env `plusDU` dus } +\end{code} + + %********************************************************* -%* * -\subsection{Value declarations} -%* * +%* * + Source-code fixity declarations +%* * %********************************************************* \begin{code} -rnSourceDecls :: [RdrNameHsDecl] -> RnMS ([RenamedHsDecl], FreeVars) - -- The decls get reversed, but that's ok - -rnSourceDecls decls - = go emptyFVs [] decls +rnSrcFixityDecls :: [LFixitySig RdrName] -> RnM FixityEnv +rnSrcFixityDecls fix_decls + = getGblEnv `thenM` \ gbl_env -> + foldlM rnFixityDecl (tcg_fix_env gbl_env) + fix_decls `thenM` \ fix_env -> + traceRn (text "fixity env" <+> pprFixEnv fix_env) `thenM_` + returnM fix_env + +rnFixityDecl :: FixityEnv -> LFixitySig RdrName -> RnM FixityEnv +rnFixityDecl fix_env (L loc (FixitySig rdr_name fixity)) + = setSrcSpan loc $ + -- GHC extension: look up both the tycon and data con + -- for con-like things + -- If neither are in scope, report an error; otherwise + -- add both to the fixity env + addLocM lookupTopFixSigNames rdr_name `thenM` \ names -> + if null names then + addLocErr rdr_name unknownNameErr `thenM_` + returnM fix_env + else + foldlM add fix_env names where - -- Fixity and deprecations have been dealt with already; ignore them - go fvs ds' [] = returnRn (ds', fvs) - go fvs ds' (FixD _:ds) = go fvs ds' ds - go fvs ds' (DeprecD _:ds) = go fvs ds' ds - go fvs ds' (d:ds) = rnDecl d `thenRn` \(d', fvs') -> - go (fvs `plusFV` fvs') (d':ds') ds + add fix_env name + = case lookupNameEnv fix_env name of + Just (FixItem _ _ loc') + -> addLocErr rdr_name (dupFixityDecl loc') `thenM_` + returnM fix_env + Nothing -> returnM (extendNameEnv fix_env name fix_item) + where + fix_item = FixItem (nameOccName name) fixity (getLoc rdr_name) + +pprFixEnv :: FixityEnv -> SDoc +pprFixEnv env + = pprWithCommas (\ (FixItem n f _) -> ppr f <+> ppr n) + (nameEnvElts env) + +dupFixityDecl loc rdr_name + = vcat [ptext SLIT("Multiple fixity declarations for") <+> quotes (ppr rdr_name), + ptext SLIT("also at ") <+> ppr loc + ] \end{code} %********************************************************* -%* * -\subsection{Value declarations} -%* * +%* * + Source-code deprecations declarations +%* * %********************************************************* -\begin{code} --- rnDecl does all the work -rnDecl :: RdrNameHsDecl -> RnMS (RenamedHsDecl, FreeVars) - -rnDecl (ValD binds) = rnTopBinds binds `thenRn` \ (new_binds, fvs) -> - returnRn (ValD new_binds, fvs) +For deprecations, all we do is check that the names are in scope. +It's only imported deprecations, dealt with in RnIfaces, that we +gather them together. +\begin{code} +rnSrcDeprecDecls :: [LDeprecDecl RdrName] -> RnM Deprecations +rnSrcDeprecDecls [] + = returnM NoDeprecs -rnDecl (SigD (IfaceSig name ty id_infos loc)) - = pushSrcLocRn loc $ - mkImportedGlobalFromRdrName name `thenRn` \ name' -> - rnHsType doc_str ty `thenRn` \ (ty',fvs1) -> - mapFvRn rnIdInfo id_infos `thenRn` \ (id_infos', fvs2) -> - returnRn (SigD (IfaceSig name' ty' id_infos' loc), fvs1 `plusFV` fvs2) - where - doc_str = text "the interface signature for" <+> quotes (ppr name) +rnSrcDeprecDecls decls + = mappM (addLocM rn_deprec) decls `thenM` \ pairs -> + returnM (DeprecSome (mkNameEnv (catMaybes pairs))) + where + rn_deprec (Deprecation rdr_name txt) + = lookupTopBndrRn rdr_name `thenM` \ name -> + returnM (Just (name, (rdrNameOcc rdr_name, txt))) + +checkModDeprec :: Maybe DeprecTxt -> Deprecations +-- Check for a module deprecation; done once at top level +checkModDeprec Nothing = NoDeprecs +checkModDeprec (Just txt) = DeprecAll txt \end{code} %********************************************************* %* * -\subsection{Type declarations} +\subsection{Source code declarations} %* * %********************************************************* -@rnTyDecl@ uses the `global name function' to create a new type -declaration in which local names have been replaced by their original -names, reporting any unknown names. - -Renaming type variables is a pain. Because they now contain uniques, -it is necessary to pass in an association list which maps a parsed -tyvar to its @Name@ representation. -In some cases (type signatures of values), -it is even necessary to go over the type first -in order to get the set of tyvars used by it, make an assoc list, -and then go over it again to rename the tyvars! -However, we can also do some scoping checks at the same time. - \begin{code} -rnDecl (TyClD (TyData new_or_data context tycon tyvars condecls nconstrs derivings pragmas src_loc)) - = pushSrcLocRn src_loc $ - lookupBndrRn tycon `thenRn` \ tycon' -> - bindTyVarsFVRn data_doc tyvars $ \ tyvars' -> - rnContext data_doc context `thenRn` \ (context', cxt_fvs) -> - checkDupOrQualNames data_doc con_names `thenRn_` - mapFvRn rnConDecl condecls `thenRn` \ (condecls', con_fvs) -> - rnDerivs derivings `thenRn` \ (derivings', deriv_fvs) -> - ASSERT(isNoDataPragmas pragmas) - returnRn (TyClD (TyData new_or_data context' tycon' tyvars' condecls' nconstrs - derivings' noDataPragmas src_loc), - cxt_fvs `plusFV` con_fvs `plusFV` deriv_fvs) +rnDefaultDecl (DefaultDecl tys) + = mapFvRn (rnHsTypeFVs doc_str) tys `thenM` \ (tys', fvs) -> + returnM (DefaultDecl tys', fvs) where - data_doc = text "the data type declaration for" <+> quotes (ppr tycon) - con_names = map conDeclName condecls - -rnDecl (TyClD (TySynonym name tyvars ty src_loc)) - = pushSrcLocRn src_loc $ - lookupBndrRn name `thenRn` \ name' -> - bindTyVarsFVRn syn_doc tyvars $ \ tyvars' -> - rnHsType syn_doc (unquantify ty) `thenRn` \ (ty', ty_fvs) -> - returnRn (TyClD (TySynonym name' tyvars' ty' src_loc), ty_fvs) - where - syn_doc = text "the declaration for type synonym" <+> quotes (ppr name) - - -- For H98 we do *not* universally quantify on the RHS of a synonym - -- Silently discard context... but the tyvars in the rest won't be in scope - unquantify (HsForAllTy Nothing ctxt ty) | not opt_GlasgowExts = ty - unquantify ty = ty - -rnDecl (TyClD (ClassDecl context cname tyvars fds sigs mbinds pragmas - tname dname dwname snames src_loc)) - = pushSrcLocRn src_loc $ - - lookupBndrRn cname `thenRn` \ cname' -> - - -- Deal with the implicit tycon and datacon name - -- They aren't in scope (because they aren't visible to the user) - -- and what we want to do is simply look them up in the cache; - -- we jolly well ought to get a 'hit' there! - -- So the 'Imported' part of this call is not relevant. - -- Unclean; but since these two are the only place this happens - -- I can't work up the energy to do it more beautifully - mkImportedGlobalFromRdrName tname `thenRn` \ tname' -> - mkImportedGlobalFromRdrName dname `thenRn` \ dname' -> - mkImportedGlobalFromRdrName dwname `thenRn` \ dwname' -> - mapRn mkImportedGlobalFromRdrName snames `thenRn` \ snames' -> - - -- Tyvars scope over bindings and context - bindTyVarsFV2Rn cls_doc tyvars ( \ clas_tyvar_names tyvars' -> - - -- Check the superclasses - rnContext cls_doc context `thenRn` \ (context', cxt_fvs) -> - - -- Check the functional dependencies - rnFds cls_doc fds `thenRn` \ (fds', fds_fvs) -> - - -- Check the signatures - let - -- First process the class op sigs, then the fixity sigs. - (op_sigs, non_op_sigs) = partition isClassOpSig sigs - in - checkDupOrQualNames sig_doc sig_rdr_names_w_locs `thenRn_` - mapFvRn (rn_op cname' clas_tyvar_names fds') op_sigs `thenRn` \ (sigs', sig_fvs) -> - let - binders = mkNameSet [ nm | (ClassOpSig nm _ _ _ _) <- sigs' ] - in - renameSigs (okClsDclSig binders) non_op_sigs `thenRn` \ (non_ops', fix_fvs) -> - - -- Check the methods - checkDupOrQualNames meth_doc meth_rdr_names_w_locs `thenRn_` - rnMethodBinds mbinds - `thenRn` \ (mbinds', meth_fvs) -> - - -- Typechecker is responsible for checking that we only - -- give default-method bindings for things in this class. - -- The renamer *could* check this for class decls, but can't - -- for instance decls. - - ASSERT(isNoClassPragmas pragmas) - returnRn (TyClD (ClassDecl context' cname' tyvars' fds' (non_ops' ++ sigs') mbinds' - NoClassPragmas tname' dname' dwname' snames' src_loc), - sig_fvs `plusFV` - fix_fvs `plusFV` - cxt_fvs `plusFV` - fds_fvs `plusFV` - meth_fvs - ) - ) - where - cls_doc = text "the declaration for class" <+> ppr cname - sig_doc = text "the signatures for class" <+> ppr cname - meth_doc = text "the default-methods for class" <+> ppr cname - - sig_rdr_names_w_locs = [(op,locn) | ClassOpSig op _ _ _ locn <- sigs] - meth_rdr_names_w_locs = bagToList (collectMonoBinders mbinds) - meth_rdr_names = map fst meth_rdr_names_w_locs - - rn_op clas clas_tyvars clas_fds sig@(ClassOpSig op dm_rdr_name explicit_dm ty locn) - = pushSrcLocRn locn $ - lookupBndrRn op `thenRn` \ op_name -> - - -- Check the signature - rnHsSigType (quotes (ppr op)) ty `thenRn` \ (new_ty, op_ty_fvs) -> - let - check_in_op_ty clas_tyvar = - checkRn (clas_tyvar `elemNameSet` oclose clas_fds op_ty_fvs) - (classTyVarNotInOpTyErr clas_tyvar sig) - in - mapRn_ check_in_op_ty clas_tyvars `thenRn_` - - -- Make the default-method name - getModeRn `thenRn` \ mode -> - (case mode of - SourceMode -> -- Source class decl - newImplicitBinder (mkDefaultMethodOcc (rdrNameOcc op)) locn `thenRn` \ dm_name -> - returnRn (dm_name, op `elem` meth_rdr_names, emptyFVs) - - InterfaceMode - -> -- Imported class that has a default method decl - -- See comments with tname, snames, above - lookupImplicitOccRn dm_rdr_name `thenRn` \ dm_name -> - returnRn (dm_name, explicit_dm, if explicit_dm then unitFV dm_name else emptyFVs) - -- An imported class decl for a class decl that had an explicit default - -- method, mentions, rather than defines, - -- the default method, so we must arrange to pull it in - ) `thenRn` \ (dm_name, final_explicit_dm, dm_fvs) -> - - returnRn (ClassOpSig op_name dm_name final_explicit_dm new_ty locn, op_ty_fvs `plusFV` dm_fvs) + doc_str = text "In a `default' declaration" \end{code} - %********************************************************* %* * -\subsection{Instance declarations} + Bindings %* * %********************************************************* -\begin{code} -rnDecl (InstD (InstDecl inst_ty mbinds uprags dfun_rdr_name src_loc)) - = pushSrcLocRn src_loc $ - rnHsSigType (text "an instance decl") inst_ty `thenRn` \ (inst_ty', inst_fvs) -> - let - inst_tyvars = case inst_ty' of - HsForAllTy (Just inst_tyvars) _ _ -> inst_tyvars - other -> [] - -- (Slightly strangely) the forall-d tyvars scope over - -- the method bindings too - in +These chaps are here, rather than in TcBinds, so that there +is just one hi-boot file (for RnSource). rnSrcDecls is part +of the loop too, and it must be defined in this module. - -- Rename the bindings - -- NB meth_names can be qualified! - checkDupNames meth_doc meth_names `thenRn_` - extendTyVarEnvFVRn inst_tyvars ( - rnMethodBinds mbinds - ) `thenRn` \ (mbinds', meth_fvs) -> - let - binders = mkNameSet (map fst (bagToList (collectMonoBinders mbinds'))) - in - -- Rename the prags and signatures. - -- Note that the type variables are not in scope here, - -- so that instance Eq a => Eq (T a) where - -- {-# SPECIALISE instance Eq a => Eq (T [a]) #-} - -- works OK. - renameSigs (okInstDclSig binders) uprags `thenRn` \ (new_uprags, prag_fvs) -> - - getModeRn `thenRn` \ mode -> - (case mode of - InterfaceMode -> lookupImplicitOccRn dfun_rdr_name `thenRn` \ dfun_name -> - returnRn (dfun_name, unitFV dfun_name) - SourceMode -> newDFunName (getDFunKey inst_ty') src_loc - `thenRn` \ dfun_name -> - returnRn (dfun_name, emptyFVs) - ) - `thenRn` \ (dfun_name, dfun_fv) -> - - -- The typechecker checks that all the bindings are for the right class. - returnRn (InstD (InstDecl inst_ty' mbinds' new_uprags dfun_name src_loc), - inst_fvs `plusFV` meth_fvs `plusFV` prag_fvs `plusFV` dfun_fv) - where - meth_doc = text "the bindings in an instance declaration" - meth_names = bagToList (collectMonoBinders mbinds) +\begin{code} +rnBindGroups :: [HsBindGroup RdrName] -> RnM ([HsBindGroup Name], DefUses) +-- This version assumes that the binders are already in scope +-- It's used only in 'mdo' +rnBindGroups [] + = returnM ([], emptyDUs) +rnBindGroups [HsBindGroup bind sigs _] + = rnBinds NotTopLevel bind sigs +rnBindGroups b@[HsIPBinds bind] + = do addErr (badIpBinds b) + returnM ([], emptyDUs) +rnBindGroups _ + = panic "rnBindGroups" + +rnBindGroupsAndThen + :: [HsBindGroup RdrName] + -> ([HsBindGroup Name] -> RnM (result, FreeVars)) + -> RnM (result, FreeVars) +-- This version (a) assumes that the binding vars are not already in scope +-- (b) removes the binders from the free vars of the thing inside +-- The parser doesn't produce ThenBinds +rnBindGroupsAndThen [] thing_inside + = thing_inside [] +rnBindGroupsAndThen [HsBindGroup bind sigs _] thing_inside + = rnBindsAndThen bind sigs $ \ groups -> thing_inside groups +rnBindGroupsAndThen [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) + +rnIPBinds [] = returnM ([], emptyFVs) +rnIPBinds (bind : binds) + = wrapLocFstM rnIPBind bind `thenM` \ (bind', fvBind) -> + rnIPBinds binds `thenM` \ (binds',fvBinds) -> + returnM (bind' : binds', fvBind `plusFV` fvBinds) + +rnIPBind (IPBind n expr) + = newIPNameRn n `thenM` \ name -> + rnLExpr expr `thenM` \ (expr',fvExpr) -> + return (IPBind name expr', fvExpr) + +badIpBinds binds + = hang (ptext SLIT("Implicit-parameter bindings illegal in 'mdo':")) 4 + (ppr binds) \end{code} + %********************************************************* %* * -\subsection{Default declarations} +\subsection{Foreign declarations} %* * %********************************************************* \begin{code} -rnDecl (DefD (DefaultDecl tys src_loc)) - = pushSrcLocRn src_loc $ - rnHsTypes doc_str tys `thenRn` \ (tys', fvs) -> - returnRn (DefD (DefaultDecl tys' src_loc), fvs) - where - doc_str = text "a `default' declaration" +rnHsForeignDecl (ForeignImport name ty spec isDeprec) + = lookupLocatedTopBndrRn name `thenM` \ name' -> + rnHsTypeFVs (fo_decl_msg name) ty `thenM` \ (ty', fvs) -> + returnM (ForeignImport name' ty' spec isDeprec, fvs) + +rnHsForeignDecl (ForeignExport name ty spec isDeprec) + = lookupLocatedOccRn name `thenM` \ name' -> + rnHsTypeFVs (fo_decl_msg name) ty `thenM` \ (ty', fvs) -> + returnM (ForeignExport name' ty' spec isDeprec, fvs ) + -- NB: a foreign export is an *occurrence site* for name, so + -- we add it to the free-variable list. It might, for example, + -- be imported from another module + +fo_decl_msg name = ptext SLIT("In the foreign declaration for") <+> ppr name \end{code} + %********************************************************* %* * -\subsection{Foreign declarations} +\subsection{Instance declarations} %* * %********************************************************* \begin{code} -rnDecl (ForD (ForeignDecl name imp_exp ty ext_nm cconv src_loc)) - = pushSrcLocRn src_loc $ - lookupOccRn name `thenRn` \ name' -> +rnSrcInstDecl (InstDecl inst_ty mbinds uprags) + -- Used for both source and interface file decls + = rnHsSigType (text "an instance decl") inst_ty `thenM` \ inst_ty' -> + + -- Rename the bindings + -- The typechecker (not the renamer) checks that all + -- the bindings are for the right class + let + meth_doc = text "In the bindings in an instance declaration" + meth_names = collectHsBindLocatedBinders mbinds + (inst_tyvars, _, cls,_) = splitHsInstDeclTy (unLoc inst_ty') + in + checkDupNames meth_doc meth_names `thenM_` + extendTyVarEnvForMethodBinds inst_tyvars ( + -- (Slightly strangely) the forall-d tyvars scope over + -- the method bindings too + rnMethodBinds cls [] mbinds + ) `thenM` \ (mbinds', meth_fvs) -> + -- Rename the prags and signatures. + -- Note that the type variables are not in scope here, + -- so that instance Eq a => Eq (T a) where + -- {-# SPECIALISE instance Eq a => Eq (T [a]) #-} + -- works OK. + -- + -- But the (unqualified) method names are in scope let - extra_fvs FoExport - | isDyn = - lookupImplicitOccsRn [makeStablePtr_RDR, deRefStablePtr_RDR, - bindIO_RDR, returnIO_RDR] - | otherwise = - lookupImplicitOccsRn [bindIO_RDR, returnIO_RDR] `thenRn` \ fvs -> - returnRn (addOneFV fvs name') - extra_fvs other = returnRn emptyFVs + binders = collectHsBindBinders mbinds' in - checkRn (ok_ext_nm ext_nm) (badExtName ext_nm) `thenRn_` + bindLocalNames binders (renameSigs uprags) `thenM` \ uprags' -> + checkSigs (okInstDclSig (mkNameSet binders)) uprags' `thenM_` - extra_fvs imp_exp `thenRn` \ fvs1 -> + returnM (InstDecl inst_ty' mbinds' uprags', + meth_fvs `plusFV` hsSigsFVs uprags' + `plusFV` extractHsTyNames inst_ty') +\end{code} - rnHsSigType fo_decl_msg ty `thenRn` \ (ty', fvs2) -> - returnRn (ForD (ForeignDecl name' imp_exp ty' ext_nm cconv src_loc), - fvs1 `plusFV` fvs2) - where - fo_decl_msg = ptext SLIT("a foreign declaration") - isDyn = isDynamicExtName ext_nm +For the method bindings in class and instance decls, we extend the +type variable environment iff -fglasgow-exts - ok_ext_nm Dynamic = True - ok_ext_nm (ExtName nm (Just mb)) = isCLabelString nm && isCLabelString mb - ok_ext_nm (ExtName nm Nothing) = isCLabelString nm +\begin{code} +extendTyVarEnvForMethodBinds tyvars thing_inside + = doptM Opt_GlasgowExts `thenM` \ opt_GlasgowExts -> + if opt_GlasgowExts then + extendTyVarEnvFVRn (map hsLTyVarName tyvars) thing_inside + else + thing_inside \end{code} + %********************************************************* %* * \subsection{Rules} @@ -384,600 +380,350 @@ rnDecl (ForD (ForeignDecl name imp_exp ty ext_nm cconv src_loc)) %********************************************************* \begin{code} -rnDecl (RuleD (IfaceRule rule_name vars fn args rhs src_loc)) - = pushSrcLocRn src_loc $ - lookupOccRn fn `thenRn` \ fn' -> - rnCoreBndrs vars $ \ vars' -> - mapFvRn rnCoreExpr args `thenRn` \ (args', fvs1) -> - rnCoreExpr rhs `thenRn` \ (rhs', fvs2) -> - returnRn (RuleD (IfaceRule rule_name vars' fn' args' rhs' src_loc), - (fvs1 `plusFV` fvs2) `addOneFV` fn') - -rnDecl (RuleD (IfaceRuleOut fn rule)) - -- This one is used for BuiltInRules - -- The rule itself is already done, but the thing - -- to attach it to is not. - = lookupOccRn fn `thenRn` \ fn' -> - returnRn (RuleD (IfaceRuleOut fn' rule), unitFV fn') - -rnDecl (RuleD (HsRule rule_name tvs vars lhs rhs src_loc)) - = ASSERT( null tvs ) - pushSrcLocRn src_loc $ - - bindTyVarsFV2Rn doc (map UserTyVar sig_tvs) $ \ sig_tvs' _ -> - bindLocalsFVRn doc (map get_var vars) $ \ ids -> - mapFvRn rn_var (vars `zip` ids) `thenRn` \ (vars', fv_vars) -> - - rnExpr lhs `thenRn` \ (lhs', fv_lhs) -> - rnExpr rhs `thenRn` \ (rhs', fv_rhs) -> - checkRn (validRuleLhs ids lhs') - (badRuleLhsErr rule_name lhs') `thenRn_` +rnHsRuleDecl (HsRule rule_name act vars lhs rhs) + = bindPatSigTyVarsFV (collectRuleBndrSigTys vars) $ + + bindLocatedLocalsFV doc (map get_var vars) $ \ ids -> + mapFvRn rn_var (vars `zip` ids) `thenM` \ (vars', fv_vars) -> + + rnLExpr lhs `thenM` \ (lhs', fv_lhs) -> + rnLExpr rhs `thenM` \ (rhs', fv_rhs) -> + let + mb_bad = validRuleLhs ids lhs' + in + checkErr (isNothing mb_bad) + (badRuleLhsErr rule_name lhs' mb_bad) `thenM_` let bad_vars = [var | var <- ids, not (var `elemNameSet` fv_lhs)] in - mapRn (addErrRn . badRuleVar rule_name) bad_vars `thenRn_` - returnRn (RuleD (HsRule rule_name sig_tvs' vars' lhs' rhs' src_loc), - fv_vars `plusFV` fv_lhs `plusFV` fv_rhs) + mappM (addErr . badRuleVar rule_name) bad_vars `thenM_` + returnM (HsRule rule_name act vars' lhs' rhs', + fv_vars `plusFV` fv_lhs `plusFV` fv_rhs) where - doc = text "the transformation rule" <+> ptext rule_name - sig_tvs = extractRuleBndrsTyVars vars + doc = text "In the transformation rule" <+> ftext rule_name get_var (RuleBndr v) = v get_var (RuleBndrSig v _) = v - rn_var (RuleBndr v, id) = returnRn (RuleBndr id, emptyFVs) - rn_var (RuleBndrSig v t, id) = rnHsType doc t `thenRn` \ (t', fvs) -> - returnRn (RuleBndrSig id t', fvs) + rn_var (RuleBndr (L loc v), id) + = returnM (RuleBndr (L loc id), emptyFVs) + rn_var (RuleBndrSig (L loc v) t, id) + = rnHsTypeFVs doc t `thenM` \ (t', fvs) -> + returnM (RuleBndrSig (L loc id) t', fvs) \end{code} +Check the shape of a transformation rule LHS. Currently +we only allow LHSs of the form @(f e1 .. en)@, where @f@ is +not one of the @forall@'d variables. We also restrict the form of the LHS so +that it may be plausibly matched. Basically you only get to write ordinary +applications. (E.g. a case expression is not allowed: too elaborate.) -%********************************************************* -%* * -\subsection{Support code for type/data declarations} -%* * -%********************************************************* - -\begin{code} -rnDerivs :: Maybe [RdrName] -> RnMS (Maybe [Name], FreeVars) - -rnDerivs Nothing -- derivs not specified - = returnRn (Nothing, emptyFVs) - -rnDerivs (Just clss) - = mapRn do_one clss `thenRn` \ clss' -> - returnRn (Just clss', mkNameSet clss') - where - do_one cls = lookupOccRn cls `thenRn` \ clas_name -> - checkRn (getUnique clas_name `elem` derivableClassKeys) - (derivingNonStdClassErr clas_name) `thenRn_` - returnRn clas_name -\end{code} +NB: if you add new cases here, make sure you add new ones to TcRule.ruleLhsTvs \begin{code} -conDeclName :: RdrNameConDecl -> (RdrName, SrcLoc) -conDeclName (ConDecl n _ _ _ _ l) = (n,l) - -rnConDecl :: RdrNameConDecl -> RnMS (RenamedConDecl, FreeVars) -rnConDecl (ConDecl name wkr tvs cxt details locn) - = pushSrcLocRn locn $ - checkConName name `thenRn_` - lookupBndrRn name `thenRn` \ new_name -> - - mkImportedGlobalFromRdrName wkr `thenRn` \ new_wkr -> - -- See comments with ClassDecl - - bindTyVarsFVRn doc tvs $ \ new_tyvars -> - rnContext doc cxt `thenRn` \ (new_context, cxt_fvs) -> - rnConDetails doc locn details `thenRn` \ (new_details, det_fvs) -> - returnRn (ConDecl new_name new_wkr new_tyvars new_context new_details locn, - cxt_fvs `plusFV` det_fvs) +validRuleLhs :: [Name] -> LHsExpr Name -> Maybe (HsExpr Name) +-- Nothing => OK +-- Just e => Not ok, and e is the offending expression +validRuleLhs foralls lhs + = checkl lhs where - doc = text "the definition of data constructor" <+> quotes (ppr name) - -rnConDetails doc locn (VanillaCon tys) - = mapFvRn (rnBangTy doc) tys `thenRn` \ (new_tys, fvs) -> - returnRn (VanillaCon new_tys, fvs) + checkl (L loc e) = check e -rnConDetails doc locn (InfixCon ty1 ty2) - = rnBangTy doc ty1 `thenRn` \ (new_ty1, fvs1) -> - rnBangTy doc ty2 `thenRn` \ (new_ty2, fvs2) -> - returnRn (InfixCon new_ty1 new_ty2, fvs1 `plusFV` fvs2) + check (OpApp e1 op _ e2) = checkl op `seqMaybe` checkl_e e1 `seqMaybe` checkl_e e2 + check (HsApp e1 e2) = checkl e1 `seqMaybe` checkl_e e2 + check (HsVar v) | v `notElem` foralls = Nothing + check other = Just other -- Failure -rnConDetails doc locn (NewCon ty mb_field) - = rnHsType doc ty `thenRn` \ (new_ty, fvs) -> - rn_field mb_field `thenRn` \ new_mb_field -> - returnRn (NewCon new_ty new_mb_field, fvs) - where - rn_field Nothing = returnRn Nothing - rn_field (Just f) = - lookupBndrRn f `thenRn` \ new_f -> - returnRn (Just new_f) - -rnConDetails doc locn (RecCon fields) - = checkDupOrQualNames doc field_names `thenRn_` - mapFvRn (rnField doc) fields `thenRn` \ (new_fields, fvs) -> - returnRn (RecCon new_fields, fvs) - where - field_names = [(fld, locn) | (flds, _) <- fields, fld <- flds] + checkl_e (L loc e) = check_e e -rnField doc (names, ty) - = mapRn lookupBndrRn names `thenRn` \ new_names -> - rnBangTy doc ty `thenRn` \ (new_ty, fvs) -> - returnRn ((new_names, new_ty), fvs) + check_e (HsVar v) = Nothing + check_e (HsPar e) = checkl_e e + check_e (HsLit e) = Nothing + check_e (HsOverLit e) = Nothing -rnBangTy doc (Banged ty) - = rnHsType doc ty `thenRn` \ (new_ty, fvs) -> - returnRn (Banged new_ty, fvs) + check_e (OpApp e1 op _ e2) = checkl_e e1 `seqMaybe` checkl_e op `seqMaybe` checkl_e e2 + check_e (HsApp e1 e2) = checkl_e e1 `seqMaybe` checkl_e e2 + check_e (NegApp e _) = checkl_e e + check_e (ExplicitList _ es) = checkl_es es + check_e (ExplicitTuple es _) = checkl_es es + check_e other = Just other -- Fails -rnBangTy doc (Unbanged ty) - = rnHsType doc ty `thenRn` \ (new_ty, fvs) -> - returnRn (Unbanged new_ty, fvs) + checkl_es es = foldr (seqMaybe . checkl_e) Nothing es -rnBangTy doc (Unpacked ty) - = rnHsType doc ty `thenRn` \ (new_ty, fvs) -> - returnRn (Unpacked new_ty, fvs) - --- This data decl will parse OK --- data T = a Int --- treating "a" as the constructor. --- It is really hard to make the parser spot this malformation. --- So the renamer has to check that the constructor is legal --- --- We can get an operator as the constructor, even in the prefix form: --- data T = :% Int Int --- from interface files, which always print in prefix form +badRuleLhsErr name lhs (Just bad_e) + = sep [ptext SLIT("Rule") <+> ftext name <> colon, + nest 4 (vcat [ptext SLIT("Illegal expression:") <+> ppr bad_e, + ptext SLIT("in left-hand side:") <+> ppr lhs])] + $$ + ptext SLIT("LHS must be of form (f e1 .. en) where f is not forall'd") -checkConName name - = checkRn (isRdrDataCon name) - (badDataCon name) +badRuleVar name var + = sep [ptext SLIT("Rule") <+> doubleQuotes (ftext name) <> colon, + ptext SLIT("Forall'd variable") <+> quotes (ppr var) <+> + ptext SLIT("does not appear on left hand side")] \end{code} %********************************************************* %* * -\subsection{Support code to rename types} +\subsection{Type, class and iface sig declarations} %* * %********************************************************* +@rnTyDecl@ uses the `global name function' to create a new type +declaration in which local names have been replaced by their original +names, reporting any unknown names. + +Renaming type variables is a pain. Because they now contain uniques, +it is necessary to pass in an association list which maps a parsed +tyvar to its @Name@ representation. +In some cases (type signatures of values), +it is even necessary to go over the type first +in order to get the set of tyvars used by it, make an assoc list, +and then go over it again to rename the tyvars! +However, we can also do some scoping checks at the same time. + \begin{code} -rnHsSigType :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars) - -- rnHsSigType is used for source-language type signatures, - -- which use *implicit* universal quantification. -rnHsSigType doc_str ty - = rnHsType (text "the type signature for" <+> doc_str) ty - ---------------------------------------- -rnHsType :: SDoc -> RdrNameHsType -> RnMS (RenamedHsType, FreeVars) - -rnHsType doc (HsForAllTy Nothing ctxt ty) - -- Implicit quantifiction in source code (no kinds on tyvars) - -- Given the signature C => T we universally quantify - -- over FV(T) \ {in-scope-tyvars} - = getLocalNameEnv `thenRn` \ name_env -> - let - mentioned_in_tau = extractHsTyRdrTyVars ty - mentioned_in_ctxt = extractHsCtxtRdrTyVars ctxt - mentioned = nub (mentioned_in_tau ++ mentioned_in_ctxt) - forall_tyvars = filter (not . (`elemFM` name_env)) mentioned - in - rnForAll doc (map UserTyVar forall_tyvars) ctxt ty - -rnHsType doc (HsForAllTy (Just forall_tyvars) ctxt tau) - -- Explicit quantification. - -- Check that the forall'd tyvars are actually - -- mentioned in the type, and produce a warning if not - = let - mentioned_in_tau = extractHsTyRdrTyVars tau - mentioned_in_ctxt = extractHsCtxtRdrTyVars ctxt - mentioned = nub (mentioned_in_tau ++ mentioned_in_ctxt) - forall_tyvar_names = hsTyVarNames forall_tyvars - - -- Explicitly quantified but not mentioned in ctxt or tau - warn_guys = filter (`notElem` mentioned) forall_tyvar_names - in - mapRn_ (forAllWarn doc tau) warn_guys `thenRn_` - rnForAll doc forall_tyvars ctxt tau - -rnHsType doc (HsTyVar tyvar) - = lookupOccRn tyvar `thenRn` \ tyvar' -> - returnRn (HsTyVar tyvar', unitFV tyvar') - -rnHsType doc (HsFunTy ty1 ty2) - = rnHsType doc ty1 `thenRn` \ (ty1', fvs1) -> - -- Might find a for-all as the arg of a function type - rnHsType doc ty2 `thenRn` \ (ty2', fvs2) -> - -- Or as the result. This happens when reading Prelude.hi - -- when we find return :: forall m. Monad m -> forall a. a -> m a - returnRn (HsFunTy ty1' ty2', fvs1 `plusFV` fvs2) - -rnHsType doc (HsListTy ty) - = rnHsType doc ty `thenRn` \ (ty', fvs) -> - returnRn (HsListTy ty', fvs `addOneFV` listTyCon_name) - --- Unboxed tuples are allowed to have poly-typed arguments. These --- sometimes crop up as a result of CPR worker-wrappering dictionaries. -rnHsType doc (HsTupleTy (HsTupCon _ boxity) tys) - -- Don't do lookupOccRn, because this is built-in syntax - -- so it doesn't need to be in scope - = mapFvRn (rnHsType doc) tys `thenRn` \ (tys', fvs) -> - returnRn (HsTupleTy (HsTupCon n' boxity) tys', fvs `addOneFV` n') - where - n' = tupleTyCon_name boxity (length tys) - +rnTyClDecl (ForeignType {tcdLName = name, tcdFoType = fo_type, tcdExtName = ext_name}) + = lookupLocatedTopBndrRn name `thenM` \ name' -> + returnM (ForeignType {tcdLName = name', tcdFoType = fo_type, tcdExtName = ext_name}, + emptyFVs) + +rnTyClDecl (TyData {tcdND = new_or_data, tcdCtxt = context, tcdLName = tycon, + tcdTyVars = tyvars, tcdCons = condecls, + tcdKindSig = sig, tcdDerivs = derivs}) + | is_vanilla -- Normal Haskell data type decl + = ASSERT( isNothing sig ) -- In normal H98 form, kind signature on the + -- data type is syntactically illegal + bindTyVarsRn data_doc tyvars $ \ tyvars' -> + do { tycon' <- lookupLocatedTopBndrRn tycon + ; context' <- rnContext data_doc context + ; (derivs', deriv_fvs) <- rn_derivs derivs + ; checkDupNames data_doc con_names + ; condecls' <- rnConDecls (unLoc tycon') condecls + ; returnM (TyData {tcdND = new_or_data, tcdCtxt = context', tcdLName = tycon', + tcdTyVars = tyvars', tcdKindSig = Nothing, tcdCons = condecls', + tcdDerivs = derivs'}, + delFVs (map hsLTyVarName tyvars') $ + extractHsCtxtTyNames context' `plusFV` + plusFVs (map conDeclFVs condecls') `plusFV` + deriv_fvs) } + + | otherwise -- GADT + = ASSERT( null (unLoc context) ) + do { tycon' <- lookupLocatedTopBndrRn tycon + ; tyvars' <- bindTyVarsRn data_doc tyvars + (\ tyvars' -> return tyvars') + -- For GADTs, the type variables in the declaration + -- do not scope over the constructor signatures + -- data T a where { T1 :: forall b. b-> b } + ; (derivs', deriv_fvs) <- rn_derivs derivs + ; checkDupNames data_doc con_names + ; condecls' <- rnConDecls (unLoc tycon') condecls + ; returnM (TyData {tcdND = new_or_data, tcdCtxt = noLoc [], tcdLName = tycon', + tcdTyVars = tyvars', tcdCons = condecls', tcdKindSig = sig, + tcdDerivs = derivs'}, + plusFVs (map conDeclFVs condecls') `plusFV` deriv_fvs) } -rnHsType doc (HsAppTy ty1 ty2) - = rnHsType doc ty1 `thenRn` \ (ty1', fvs1) -> - rnHsType doc ty2 `thenRn` \ (ty2', fvs2) -> - returnRn (HsAppTy ty1' ty2', fvs1 `plusFV` fvs2) - -rnHsType doc (HsPredTy pred) - = rnPred doc pred `thenRn` \ (pred', fvs) -> - returnRn (HsPredTy pred', fvs) - -rnHsType doc (HsUsgForAllTy uv_rdr ty) - = bindUVarRn doc uv_rdr $ \ uv_name -> - rnHsType doc ty `thenRn` \ (ty', fvs) -> - returnRn (HsUsgForAllTy uv_name ty', - fvs ) - -rnHsType doc (HsUsgTy usg ty) - = newUsg usg `thenRn` \ (usg', usg_fvs) -> - rnHsType doc ty `thenRn` \ (ty', ty_fvs) -> - -- A for-all can occur inside a usage annotation - returnRn (HsUsgTy usg' ty', - usg_fvs `plusFV` ty_fvs) where - newUsg usg = case usg of - HsUsOnce -> returnRn (HsUsOnce, emptyFVs) - HsUsMany -> returnRn (HsUsMany, emptyFVs) - HsUsVar uv_rdr -> lookupOccRn uv_rdr `thenRn` \ uv_name -> - returnRn (HsUsVar uv_name, emptyFVs) + is_vanilla = case condecls of -- Yuk + [] -> True + L _ (ConDecl {}) : _ -> True + other -> False -rnHsTypes doc tys = mapFvRn (rnHsType doc) tys -\end{code} + data_doc = text "In the data type declaration for" <+> quotes (ppr tycon) + con_names = map con_names_helper condecls -\begin{code} --- We use lookupOcc here because this is interface file only stuff --- and we need the workers... -rnHsTupCon (HsTupCon n boxity) - = lookupOccRn n `thenRn` \ n' -> - returnRn (HsTupCon n' boxity, unitFV n') - -rnHsTupConWkr (HsTupCon n boxity) - -- Tuple construtors are for the *worker* of the tuple - -- Going direct saves needless messing about - = lookupOccRn (mkRdrNameWkr n) `thenRn` \ n' -> - returnRn (HsTupCon n' boxity, unitFV n') -\end{code} + con_names_helper (L _ (ConDecl n _ _ _)) = n + con_names_helper (L _ (GadtDecl n _)) = n -\begin{code} --- Check that each constraint mentions at least one of the forall'd type variables --- Since the forall'd type variables are a subset of the free tyvars --- of the tau-type part, this guarantees that every constraint mentions --- at least one of the free tyvars in ty -checkConstraints doc forall_tyvars tau_vars ctxt ty - = mapRn (checkPred doc forall_tyvars ty) ctxt `thenRn` \ maybe_ctxt' -> - returnRn (catMaybes maybe_ctxt') - -- Remove problem ones, to avoid duplicate error message. - -checkPred doc forall_tyvars ty p@(HsPClass clas tys) - | not_univ = failWithRn Nothing (univErr doc p ty) - | otherwise = returnRn (Just p) + rn_derivs Nothing = returnM (Nothing, emptyFVs) + rn_derivs (Just ds) = rnLHsTypes data_doc ds `thenM` \ ds' -> + returnM (Just ds', extractHsTyNames_s ds') + +rnTyClDecl (TySynonym {tcdLName = name, tcdTyVars = tyvars, tcdSynRhs = ty}) + = lookupLocatedTopBndrRn name `thenM` \ name' -> + bindTyVarsRn syn_doc tyvars $ \ tyvars' -> + rnHsTypeFVs syn_doc ty `thenM` \ (ty', fvs) -> + returnM (TySynonym {tcdLName = name', tcdTyVars = tyvars', + tcdSynRhs = ty'}, + delFVs (map hsLTyVarName tyvars') fvs) where - ct_vars = extractHsTysRdrTyVars tys - not_univ = -- At least one of the tyvars in each constraint must - -- be universally quantified. This restriction isn't in Hugs - not (any (`elem` forall_tyvars) ct_vars) -checkPred doc forall_tyvars ty p@(HsPIParam _ _) - = returnRn (Just p) - -rnForAll doc forall_tyvars ctxt ty - = bindTyVarsFVRn doc forall_tyvars $ \ new_tyvars -> - rnContext doc ctxt `thenRn` \ (new_ctxt, cxt_fvs) -> - rnHsType doc ty `thenRn` \ (new_ty, ty_fvs) -> - returnRn (mkHsForAllTy (Just new_tyvars) new_ctxt new_ty, - cxt_fvs `plusFV` ty_fvs) -\end{code} + syn_doc = text "In the declaration for type synonym" <+> quotes (ppr name) -\begin{code} -rnContext :: SDoc -> RdrNameContext -> RnMS (RenamedContext, FreeVars) -rnContext doc ctxt - = mapAndUnzipRn rn_pred ctxt `thenRn` \ (theta, fvs_s) -> +rnTyClDecl (ClassDecl {tcdCtxt = context, tcdLName = cname, + tcdTyVars = tyvars, tcdFDs = fds, tcdSigs = sigs, + tcdMeths = mbinds}) + = lookupLocatedTopBndrRn cname `thenM` \ cname' -> + + -- Tyvars scope over superclass context and method signatures + bindTyVarsRn cls_doc tyvars ( \ tyvars' -> + rnContext cls_doc context `thenM` \ context' -> + rnFds cls_doc fds `thenM` \ fds' -> + renameSigs sigs `thenM` \ sigs' -> + returnM (tyvars', context', fds', sigs') + ) `thenM` \ (tyvars', context', fds', sigs') -> + + -- Check the signatures + -- First process the class op sigs (op_sigs), then the fixity sigs (non_op_sigs). let - (_, dups) = removeDupsEq theta - -- We only have equality, not ordering + sig_rdr_names_w_locs = [op | L _ (Sig op _) <- sigs] in - -- Check for duplicate assertions - -- If this isn't an error, then it ought to be: - mapRn (addWarnRn . dupClassAssertWarn theta) dups `thenRn_` - returnRn (theta, plusFVs fvs_s) - where - --Someone discovered that @CCallable@ and @CReturnable@ - -- could be used in contexts such as: - -- foo :: CCallable a => a -> PrimIO Int - -- Doing this utterly wrecks the whole point of introducing these - -- classes so we specifically check that this isn't being done. - rn_pred pred = rnPred doc pred `thenRn` \ (pred', fvs)-> - checkRn (not (bad_pred pred')) - (naughtyCCallContextErr pred') `thenRn_` - returnRn (pred', fvs) - - bad_pred (HsPClass clas _) = getUnique clas `elem` cCallishClassKeys - bad_pred other = False - - -rnPred doc (HsPClass clas tys) - = lookupOccRn clas `thenRn` \ clas_name -> - rnHsTypes doc tys `thenRn` \ (tys', fvs) -> - returnRn (HsPClass clas_name tys', fvs `addOneFV` clas_name) - -rnPred doc (HsPIParam n ty) - = getIPName n `thenRn` \ name -> - rnHsType doc ty `thenRn` \ (ty', fvs) -> - returnRn (HsPIParam name ty', fvs) -\end{code} - -\begin{code} -rnFds :: SDoc -> [FunDep RdrName] -> RnMS ([FunDep Name], FreeVars) + checkDupNames sig_doc sig_rdr_names_w_locs `thenM_` + checkSigs okClsDclSig sigs' `thenM_` + -- Typechecker is responsible for checking that we only + -- give default-method bindings for things in this class. + -- The renamer *could* check this for class decls, but can't + -- for instance decls. -rnFds doc fds - = mapAndUnzipRn rn_fds fds `thenRn` \ (theta, fvs_s) -> - returnRn (theta, plusFVs fvs_s) + -- The newLocals call is tiresome: given a generic class decl + -- class C a where + -- op :: a -> a + -- op {| x+y |} (Inl a) = ... + -- op {| x+y |} (Inr b) = ... + -- op {| a*b |} (a*b) = ... + -- we want to name both "x" tyvars with the same unique, so that they are + -- easy to group together in the typechecker. + extendTyVarEnvForMethodBinds tyvars' ( + getLocalRdrEnv `thenM` \ name_env -> + let + meth_rdr_names_w_locs = collectHsBindLocatedBinders mbinds + gen_rdr_tyvars_w_locs = + [ tv | tv <- extractGenericPatTyVars mbinds, + not (unLoc tv `elemLocalRdrEnv` name_env) ] + in + checkDupNames meth_doc meth_rdr_names_w_locs `thenM_` + newLocalsRn gen_rdr_tyvars_w_locs `thenM` \ gen_tyvars -> + rnMethodBinds (unLoc cname') gen_tyvars mbinds + ) `thenM` \ (mbinds', meth_fvs) -> + + returnM (ClassDecl { tcdCtxt = context', tcdLName = cname', tcdTyVars = tyvars', + tcdFDs = fds', tcdSigs = sigs', tcdMeths = mbinds'}, + delFVs (map hsLTyVarName tyvars') $ + extractHsCtxtTyNames context' `plusFV` + plusFVs (map extractFunDepNames (map unLoc fds')) `plusFV` + hsSigsFVs sigs' `plusFV` + meth_fvs) where - rn_fds (tys1, tys2) - = rnHsTyVars doc tys1 `thenRn` \ (tys1', fvs1) -> - rnHsTyVars doc tys2 `thenRn` \ (tys2', fvs2) -> - returnRn ((tys1', tys2'), fvs1 `plusFV` fvs2) - -rnHsTyVars doc tvs = mapFvRn (rnHsTyvar doc) tvs -rnHsTyvar doc tyvar - = lookupOccRn tyvar `thenRn` \ tyvar' -> - returnRn (tyvar', unitFV tyvar') + meth_doc = text "In the default-methods for class" <+> ppr cname + cls_doc = text "In the declaration for class" <+> ppr cname + sig_doc = text "In the signatures for class" <+> ppr cname \end{code} %********************************************************* -%* * -\subsection{IdInfo} -%* * +%* * +\subsection{Support code for type/data declarations} +%* * %********************************************************* \begin{code} -rnIdInfo (HsStrictness str) = returnRn (HsStrictness str, emptyFVs) - -rnIdInfo (HsWorker worker) - = lookupOccRn worker `thenRn` \ worker' -> - returnRn (HsWorker worker', unitFV worker') - -rnIdInfo (HsUnfold inline expr) = rnCoreExpr expr `thenRn` \ (expr', fvs) -> - returnRn (HsUnfold inline expr', fvs) -rnIdInfo (HsArity arity) = returnRn (HsArity arity, emptyFVs) -rnIdInfo (HsUpdate update) = returnRn (HsUpdate update, emptyFVs) -rnIdInfo HsNoCafRefs = returnRn (HsNoCafRefs, emptyFVs) -rnIdInfo HsCprInfo = returnRn (HsCprInfo, emptyFVs) - -\end{code} - -@UfCore@ expressions. - -\begin{code} -rnCoreExpr (UfType ty) - = rnHsType (text "unfolding type") ty `thenRn` \ (ty', fvs) -> - returnRn (UfType ty', fvs) - -rnCoreExpr (UfVar v) - = lookupOccRn v `thenRn` \ v' -> - returnRn (UfVar v', unitFV v') - -rnCoreExpr (UfLit l) - = returnRn (UfLit l, emptyFVs) - -rnCoreExpr (UfLitLit l ty) - = rnHsType (text "litlit") ty `thenRn` \ (ty', fvs) -> - returnRn (UfLitLit l ty', fvs) - -rnCoreExpr (UfCCall cc ty) - = rnHsType (text "ccall") ty `thenRn` \ (ty', fvs) -> - returnRn (UfCCall cc ty', fvs) - -rnCoreExpr (UfTuple con args) - = rnHsTupConWkr con `thenRn` \ (con', fvs1) -> - mapFvRn rnCoreExpr args `thenRn` \ (args', fvs2) -> - returnRn (UfTuple con' args', fvs1 `plusFV` fvs2) - -rnCoreExpr (UfApp fun arg) - = rnCoreExpr fun `thenRn` \ (fun', fv1) -> - rnCoreExpr arg `thenRn` \ (arg', fv2) -> - returnRn (UfApp fun' arg', fv1 `plusFV` fv2) - -rnCoreExpr (UfCase scrut bndr alts) - = rnCoreExpr scrut `thenRn` \ (scrut', fvs1) -> - bindCoreLocalFVRn bndr ( \ bndr' -> - mapFvRn rnCoreAlt alts `thenRn` \ (alts', fvs2) -> - returnRn (UfCase scrut' bndr' alts', fvs2) - ) `thenRn` \ (case', fvs3) -> - returnRn (case', fvs1 `plusFV` fvs3) - -rnCoreExpr (UfNote note expr) - = rnNote note `thenRn` \ (note', fvs1) -> - rnCoreExpr expr `thenRn` \ (expr', fvs2) -> - returnRn (UfNote note' expr', fvs1 `plusFV` fvs2) - -rnCoreExpr (UfLam bndr body) - = rnCoreBndr bndr $ \ bndr' -> - rnCoreExpr body `thenRn` \ (body', fvs) -> - returnRn (UfLam bndr' body', fvs) - -rnCoreExpr (UfLet (UfNonRec bndr rhs) body) - = rnCoreExpr rhs `thenRn` \ (rhs', fvs1) -> - rnCoreBndr bndr ( \ bndr' -> - rnCoreExpr body `thenRn` \ (body', fvs2) -> - returnRn (UfLet (UfNonRec bndr' rhs') body', fvs2) - ) `thenRn` \ (result, fvs3) -> - returnRn (result, fvs1 `plusFV` fvs3) - -rnCoreExpr (UfLet (UfRec pairs) body) - = rnCoreBndrs bndrs $ \ bndrs' -> - mapFvRn rnCoreExpr rhss `thenRn` \ (rhss', fvs1) -> - rnCoreExpr body `thenRn` \ (body', fvs2) -> - returnRn (UfLet (UfRec (bndrs' `zip` rhss')) body', fvs1 `plusFV` fvs2) +rnConDecls :: Name -> [LConDecl RdrName] -> RnM [LConDecl Name] +rnConDecls tycon condecls + = -- Check that there's at least one condecl, + -- or else we're reading an interface file, or -fglasgow-exts + (if null condecls then + doptM Opt_GlasgowExts `thenM` \ glaExts -> + checkErr glaExts (emptyConDeclsErr tycon) + else returnM () + ) `thenM_` + mappM (wrapLocM rnConDecl) condecls + +rnConDecl :: ConDecl RdrName -> RnM (ConDecl Name) +rnConDecl (ConDecl name tvs cxt details) + = addLocM checkConName name `thenM_` + lookupLocatedTopBndrRn name `thenM` \ new_name -> + + bindTyVarsRn doc tvs $ \ new_tyvars -> + rnContext doc cxt `thenM` \ new_context -> + rnConDetails doc details `thenM` \ new_details -> + returnM (ConDecl new_name new_tyvars new_context new_details) where - (bndrs, rhss) = unzip pairs -\end{code} + doc = text "In the definition of data constructor" <+> quotes (ppr name) -\begin{code} -rnCoreBndr (UfValBinder name ty) thing_inside - = rnHsType doc ty `thenRn` \ (ty', fvs1) -> - bindCoreLocalFVRn name ( \ name' -> - thing_inside (UfValBinder name' ty') - ) `thenRn` \ (result, fvs2) -> - returnRn (result, fvs1 `plusFV` fvs2) +rnConDecl (GadtDecl name ty) + = addLocM checkConName name `thenM_` + lookupLocatedTopBndrRn name `thenM` \ new_name -> + rnHsSigType doc ty `thenM` \ new_ty -> + returnM (GadtDecl new_name new_ty) where - doc = text "unfolding id" - -rnCoreBndr (UfTyBinder name kind) thing_inside - = bindCoreLocalFVRn name $ \ name' -> - thing_inside (UfTyBinder name' kind) - -rnCoreBndrs [] thing_inside = thing_inside [] -rnCoreBndrs (b:bs) thing_inside = rnCoreBndr b $ \ name' -> - rnCoreBndrs bs $ \ names' -> - thing_inside (name':names') -\end{code} - -\begin{code} -rnCoreAlt (con, bndrs, rhs) - = rnUfCon con bndrs `thenRn` \ (con', fvs1) -> - bindCoreLocalsFVRn bndrs ( \ bndrs' -> - rnCoreExpr rhs `thenRn` \ (rhs', fvs2) -> - returnRn ((con', bndrs', rhs'), fvs2) - ) `thenRn` \ (result, fvs3) -> - returnRn (result, fvs1 `plusFV` fvs3) + doc = text "In the definition of data constructor" <+> quotes (ppr name) -rnNote (UfCoerce ty) - = rnHsType (text "unfolding coerce") ty `thenRn` \ (ty', fvs) -> - returnRn (UfCoerce ty', fvs) +rnConDetails doc (PrefixCon tys) + = mappM (rnLHsType doc) tys `thenM` \ new_tys -> + returnM (PrefixCon new_tys) -rnNote (UfSCC cc) = returnRn (UfSCC cc, emptyFVs) -rnNote UfInlineCall = returnRn (UfInlineCall, emptyFVs) -rnNote UfInlineMe = returnRn (UfInlineMe, emptyFVs) +rnConDetails doc (InfixCon ty1 ty2) + = rnLHsType doc ty1 `thenM` \ new_ty1 -> + rnLHsType doc ty2 `thenM` \ new_ty2 -> + returnM (InfixCon new_ty1 new_ty2) +rnConDetails doc (RecCon fields) + = checkDupNames doc field_names `thenM_` + mappM (rnField doc) fields `thenM` \ new_fields -> + returnM (RecCon new_fields) + where + field_names = [fld | (fld, _) <- fields] -rnUfCon UfDefault _ - = returnRn (UfDefault, emptyFVs) +rnField doc (name, ty) + = lookupLocatedTopBndrRn name `thenM` \ new_name -> + rnLHsType doc ty `thenM` \ new_ty -> + returnM (new_name, new_ty) -rnUfCon (UfTupleAlt tup_con) bndrs - = rnHsTupCon tup_con `thenRn` \ (HsTupCon con' _, fvs) -> - returnRn (UfDataAlt con', fvs) - -- Makes the type checker a little easier +-- This data decl will parse OK +-- data T = a Int +-- treating "a" as the constructor. +-- It is really hard to make the parser spot this malformation. +-- So the renamer has to check that the constructor is legal +-- +-- We can get an operator as the constructor, even in the prefix form: +-- data T = :% Int Int +-- from interface files, which always print in prefix form -rnUfCon (UfDataAlt con) _ - = lookupOccRn con `thenRn` \ con' -> - returnRn (UfDataAlt con', unitFV con') +checkConName name = checkErr (isRdrDataCon name) (badDataCon name) -rnUfCon (UfLitAlt lit) _ - = returnRn (UfLitAlt lit, emptyFVs) +badDataCon name + = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)] -rnUfCon (UfLitLitAlt lit ty) _ - = rnHsType (text "litlit") ty `thenRn` \ (ty', fvs) -> - returnRn (UfLitLitAlt lit ty', fvs) +emptyConDeclsErr tycon + = sep [quotes (ppr tycon) <+> ptext SLIT("has no constructors"), + nest 4 (ptext SLIT("(-fglasgow-exts permits this)"))] \end{code} + %********************************************************* -%* * -\subsection{Rule shapes} -%* * +%* * +\subsection{Support code to rename types} +%* * %********************************************************* -Check the shape of a transformation rule LHS. Currently -we only allow LHSs of the form @(f e1 .. en)@, where @f@ is -not one of the @forall@'d variables. - \begin{code} -validRuleLhs foralls lhs - = check lhs +rnFds :: SDoc -> [Located (FunDep RdrName)] -> RnM [Located (FunDep Name)] + +rnFds doc fds + = mappM (wrapLocM rn_fds) fds where - check (HsApp e1 e2) = check e1 - check (HsVar v) | v `notElem` foralls = True - check other = False + rn_fds (tys1, tys2) + = rnHsTyVars doc tys1 `thenM` \ tys1' -> + rnHsTyVars doc tys2 `thenM` \ tys2' -> + returnM (tys1', tys2') + +rnHsTyVars doc tvs = mappM (rnHsTyvar doc) tvs +rnHsTyvar doc tyvar = lookupOccRn tyvar \end{code} %********************************************************* -%* * -\subsection{Errors} -%* * +%* * + Splices +%* * %********************************************************* \begin{code} -derivingNonStdClassErr clas - = hsep [ptext SLIT("non-standard class"), ppr clas, ptext SLIT("in deriving clause")] - -classTyVarNotInOpTyErr clas_tyvar sig - = hang (hsep [ptext SLIT("Class type variable"), - quotes (ppr clas_tyvar), - ptext SLIT("does not appear in method signature")]) - 4 (ppr sig) - -badDataCon name - = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)] - -forAllWarn doc ty tyvar - | not opt_WarnUnusedMatches = returnRn () - | otherwise - = getModeRn `thenRn` \ mode -> - case mode of { -#ifndef DEBUG - InterfaceMode -> returnRn () ; -- Don't warn of unused tyvars in interface files - -- unless DEBUG is on, in which case it is slightly - -- informative. They can arise from mkRhsTyLam, -#endif -- leading to (say) f :: forall a b. [b] -> [b] - other -> - - addWarnRn ( - sep [ptext SLIT("The universally quantified type variable") <+> quotes (ppr tyvar), - nest 4 (ptext SLIT("does not appear in the type") <+> quotes (ppr ty))] - $$ - (ptext SLIT("In") <+> doc)) - } - -forAllErr doc ty tyvar - = addErrRn ( - sep [ptext SLIT("The constrained type variable") <+> quotes (ppr tyvar), - nest 4 (ptext SLIT("does not appear in the type") <+> quotes (ppr ty))] - $$ - (ptext SLIT("In") <+> doc)) - -univErr doc constraint ty - = sep [ptext SLIT("All of the type variable(s) in the constraint") - <+> quotes (ppr constraint) - <+> ptext SLIT("are already in scope"), - nest 4 (ptext SLIT("At least one must be universally quantified here")) - ] - $$ - (ptext SLIT("In") <+> doc) - -badRuleLhsErr name lhs - = sep [ptext SLIT("Rule") <+> ptext name <> colon, - nest 4 (ptext SLIT("Illegal left-hand side:") <+> ppr lhs)] - $$ - ptext SLIT("LHS must be of form (f e1 .. en) where f is not forall'd") - -badRuleVar name var - = sep [ptext SLIT("Rule") <+> ptext name <> colon, - ptext SLIT("Forall'd variable") <+> quotes (ppr var) <+> - ptext SLIT("does not appear on left hand side")] - -badExtName :: ExtName -> Message -badExtName ext_nm - = sep [quotes (ppr ext_nm) <+> ptext SLIT("is not a valid C identifier")] - -dupClassAssertWarn ctxt (assertion : dups) - = sep [hsep [ptext SLIT("Duplicate class assertion"), - quotes (ppr assertion), - ptext SLIT("in the context:")], - nest 4 (pprHsContext ctxt <+> ptext SLIT("..."))] - -naughtyCCallContextErr (HsPClass clas _) - = sep [ptext SLIT("Can't use class") <+> quotes (ppr clas), - ptext SLIT("in a context")] +rnSplice :: HsSplice RdrName -> RnM (HsSplice Name, FreeVars) +rnSplice (HsSplice n expr) + = checkTH expr "splice" `thenM_` + getSrcSpanM `thenM` \ loc -> + newLocalsRn [L loc n] `thenM` \ [n'] -> + rnLExpr expr `thenM` \ (expr', fvs) -> + returnM (HsSplice n' expr', fvs) \end{code}