X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;ds=sidebyside;f=ghc%2Fcompiler%2Frename%2FRnSource.lhs;h=9150440aeee654159d32276a54069cba77c03a52;hb=3c96346b3685f83885cea7906b0dbc536d7695f6;hp=10a7fd89861b093cfbd67a2f5122267eea528564;hpb=57d07fb8c739fb50f957c25e8987632d04da3969;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnSource.lhs b/ghc/compiler/rename/RnSource.lhs index 10a7fd8..9150440 100644 --- a/ghc/compiler/rename/RnSource.lhs +++ b/ghc/compiler/rename/RnSource.lhs @@ -1,229 +1,269 @@ % -% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996 +% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % \section[RnSource]{Main pass of renamer} \begin{code} -module RnSource ( rnDecl, rnHsType, rnHsSigType ) where +module RnSource ( + rnSrcDecls, addTcgDUs, + rnTyClDecls, checkModDeprec, + rnSplice, checkTH + ) where #include "HsVersions.h" -import RnExpr +import {-# SOURCE #-} RnExpr( rnLExpr ) + import HsSyn -import HsDecls ( HsIdInfo(..), HsStrictnessInfo(..) ) -import HsPragmas -import HsTypes ( getTyVarName, pprClassAssertion, cmpHsTypes ) -import RdrHsSyn +import RdrName ( RdrName, isRdrDataCon, elemLocalRdrEnv, globalRdrEnvElts, + GlobalRdrElt(..), isLocalGRE ) +import RdrHsSyn ( extractGenericPatTyVars, extractHsRhoRdrTyVars ) import RnHsSyn -import HsCore -import CmdLineOpts ( opt_IgnoreIfacePragmas ) - +import RnTypes ( rnLHsType, rnLHsTypes, rnHsSigType, rnHsTypeFVs, rnContext ) import RnBinds ( rnTopBinds, rnMethodBinds, renameSigs ) -import RnEnv ( bindTyVarsRn, lookupBndrRn, lookupOccRn, lookupImplicitOccRn, bindLocalsRn, - newDfunName, checkDupOrQualNames, checkDupNames, lookupGlobalOccRn, - newLocallyDefinedGlobalName, newImportedGlobalName, ifaceFlavour, - listType_RDR, tupleType_RDR, addImplicitOccRn - ) -import RnMonad - -import Name ( Name, OccName(..), occNameString, prefixOccName, - ExportFlag(..), Provenance(..), NameSet, mkNameSet, - elemNameSet, nameOccName, NamedThing(..) - ) -import BasicTypes ( TopLevelFlag(..) ) -import FiniteMap ( lookupFM ) -import Id ( GenId{-instance NamedThing-} ) -import IdInfo ( FBTypeInfo, ArgUsageInfo ) -import Lex ( isLexCon ) -import PrelInfo ( derivingOccurrences, evalClass_RDR, numClass_RDR, allClass_NAME, - ioOkDataCon_NAME +import RnEnv ( lookupLocalDataTcNames, + lookupLocatedTopBndrRn, lookupLocatedOccRn, + lookupOccRn, newLocalsRn, + bindLocatedLocalsFV, bindPatSigTyVarsFV, + bindTyVarsRn, extendTyVarEnvFVRn, + bindLocalNames, checkDupNames, mapFvRn ) -import Maybes ( maybeToBool ) -import Bag ( bagToList ) +import TcRnMonad + +import HscTypes ( FixityEnv, FixItem(..), + Deprecations, Deprecs(..), DeprecTxt, plusDeprecs ) +import Class ( FunDep ) +import Name ( Name, nameOccName ) +import NameSet +import NameEnv +import OccName ( occEnvElts ) import Outputable -import SrcLoc ( SrcLoc ) -import Unique ( Unique ) -import UniqSet ( UniqSet ) -import UniqFM ( UniqFM, lookupUFM ) -import Util -import List ( partition, nub ) +import SrcLoc ( Located(..), unLoc, getLoc, noLoc ) +import DynFlags ( DynFlag(..) ) +import Maybes ( seqMaybe ) +import Maybe ( isNothing ) +import BasicTypes ( Boxity(..) ) \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} \item Checks that tyvars are used properly. This includes checking for undefined tyvars, and tyvars in contexts that are ambiguous. +(Some of this checking has now been moved to module @TcMonoType@, +since we don't have functional dependency information at this point.) \item Checks that all variable occurences are defined. \item -Checks the (..) etc constraints in the export list. +Checks the @(..)@ etc constraints in the export list. \end{enumerate} +\begin{code} +rnSrcDecls :: HsGroup RdrName -> RnM (TcGblEnv, HsGroup Name) + +rnSrcDecls (HsGroup { hs_valds = val_decls, + 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 <- rnSrcFixityDeclsEnv fix_decls ; + rn_fix_decls <- 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 val_decls ; + 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 = rn_fix_decls, + 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} -rnDecl :: RdrNameHsDecl -> RnMS s RenamedHsDecl +rnSrcFixityDecls :: [LFixitySig RdrName] -> RnM [LFixitySig Name] +rnSrcFixityDecls fix_decls + = do fix_decls <- mapM rnFixityDecl fix_decls + return (concat fix_decls) + +rnFixityDecl :: LFixitySig RdrName -> RnM [LFixitySig Name] +rnFixityDecl (L loc (FixitySig (L nameLoc rdr_name) fixity)) + = do names <- lookupLocalDataTcNames rdr_name + return [ L loc (FixitySig (L nameLoc name) fixity) + | name <- names ] + +rnSrcFixityDeclsEnv :: [LFixitySig RdrName] -> RnM FixityEnv +rnSrcFixityDeclsEnv fix_decls + = getGblEnv `thenM` \ gbl_env -> + foldlM rnFixityDeclEnv (tcg_fix_env gbl_env) + fix_decls `thenM` \ fix_env -> + traceRn (text "fixity env" <+> pprFixEnv fix_env) `thenM_` + returnM fix_env + +rnFixityDeclEnv :: FixityEnv -> LFixitySig RdrName -> RnM FixityEnv +rnFixityDeclEnv 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 lookupLocalDataTcNames rdr_name `thenM` \ names -> + foldlM add fix_env names + where + 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} -rnDecl (ValD binds) = rnTopBinds binds `thenRn` \ new_binds -> - returnRn (ValD new_binds) +%********************************************************* +%* * + Source-code deprecations declarations +%* * +%********************************************************* -rnDecl (SigD (IfaceSig name ty id_infos loc)) - = pushSrcLocRn loc $ - lookupBndrRn name `thenRn` \ name' -> - rnHsType ty `thenRn` \ ty' -> +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. - -- Get the pragma info (if any). - getModeRn `thenRn` \ (InterfaceMode _ print_unqual) -> - setModeRn (InterfaceMode Optional print_unqual) $ - -- In all the rest of the signature we read in optional mode, - -- so that (a) we don't die - mapRn rnIdInfo id_infos `thenRn` \ id_infos' -> - returnRn (SigD (IfaceSig name' ty' id_infos' loc)) +\begin{code} +rnSrcDeprecDecls :: [LDeprecDecl RdrName] -> RnM Deprecations +rnSrcDeprecDecls [] + = returnM NoDeprecs + +rnSrcDeprecDecls decls + = mappM (addLocM rn_deprec) decls `thenM` \ pairs_s -> + returnM (DeprecSome (mkNameEnv (concat pairs_s))) + where + rn_deprec (Deprecation rdr_name txt) + = lookupLocalDataTcNames rdr_name `thenM` \ names -> + returnM [(name, (nameOccName name, txt)) | name <- names] + +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 (TyD (TyData new_or_data context tycon tyvars condecls derivings pragmas src_loc)) - = pushSrcLocRn src_loc $ - lookupBndrRn tycon `thenRn` \ tycon' -> - bindTyVarsRn data_doc tyvars $ \ tyvars' -> - rnContext context `thenRn` \ context' -> - checkDupOrQualNames data_doc con_names `thenRn_` - mapRn rnConDecl condecls `thenRn` \ condecls' -> - rnDerivs derivings `thenRn` \ derivings' -> - ASSERT(isNoDataPragmas pragmas) - returnRn (TyD (TyData new_or_data context' tycon' tyvars' condecls' derivings' noDataPragmas src_loc)) +rnDefaultDecl (DefaultDecl tys) + = mapFvRn (rnHsTypeFVs doc_str) tys `thenM` \ (tys', fvs) -> + returnM (DefaultDecl tys', fvs) where - data_doc = text "the data type declaration for" <+> ppr tycon - con_names = map conDeclName condecls - -rnDecl (TyD (TySynonym name tyvars ty src_loc)) - = pushSrcLocRn src_loc $ - lookupBndrRn name `thenRn` \ name' -> - bindTyVarsRn syn_doc tyvars $ \ tyvars' -> - rnHsType ty `thenRn` \ ty' -> - returnRn (TyD (TySynonym name' tyvars' ty' src_loc)) - where - syn_doc = text "the declaration for type synonym" <+> ppr name + doc_str = text "In a `default' declaration" \end{code} %********************************************************* %* * -\subsection{Class declarations} +\subsection{Foreign declarations} %* * %********************************************************* -@rnClassDecl@ uses the `global name function' to create a new -class declaration in which local names have been replaced by their -original names, reporting any unknown names. - \begin{code} -rnDecl (ClD (ClassDecl context cname tyvars sigs mbinds pragmas tname dname src_loc)) - = pushSrcLocRn src_loc $ - - lookupBndrRn cname `thenRn` \ cname' -> - lookupBndrRn tname `thenRn` \ tname' -> - lookupBndrRn dname `thenRn` \ dname' -> - - bindTyVarsRn cls_doc tyvars ( \ tyvars' -> - rnContext context `thenRn` \ context' -> - - -- Check the signatures - let - clas_tyvar_names = map getTyVarName tyvars' - in - checkDupOrQualNames sig_doc sig_rdr_names_w_locs `thenRn_` - mapRn (rn_op cname' clas_tyvar_names) sigs `thenRn` \ sigs' -> - returnRn (tyvars', context', sigs') - ) `thenRn` \ (tyvars', context', sigs') -> - - -- Check the methods - checkDupOrQualNames meth_doc meth_rdr_names_w_locs `thenRn_` - rnMethodBinds mbinds `thenRn` \ mbinds' -> - - -- 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 (ClD (ClassDecl context' cname' tyvars' sigs' mbinds' NoClassPragmas tname' dname' src_loc)) - 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 sig@(ClassOpSig op maybe_dm ty locn) - = pushSrcLocRn locn $ - lookupBndrRn op `thenRn` \ op_name -> - rnHsSigType (quotes (ppr op)) ty `thenRn` \ new_ty -> - - -- Make the default-method name - let - dm_occ = prefixOccName SLIT("$m") (rdrNameOcc op) - in - getModuleRn `thenRn` \ mod_name -> - getModeRn `thenRn` \ mode -> - (case (mode, maybe_dm) of - (SourceMode, _) | op `elem` meth_rdr_names - -> -- There's an explicit method decl - newLocallyDefinedGlobalName mod_name dm_occ - (\_ -> Exported) locn `thenRn` \ dm_name -> - returnRn (Just dm_name) - - (InterfaceMode _ _, Just _) - -> -- Imported class that has a default method decl - newImportedGlobalName mod_name dm_occ (ifaceFlavour clas) `thenRn` \ dm_name -> - addOccurrenceName dm_name `thenRn_` - returnRn (Just dm_name) - - other -> returnRn Nothing - ) `thenRn` \ maybe_dm_name -> - - -- Check that each class tyvar appears in op_ty - let - (ctxt, op_ty) = case new_ty of - HsForAllTy tvs ctxt op_ty -> (ctxt, op_ty) - other -> ([], new_ty) - ctxt_fvs = extractHsCtxtTyNames ctxt -- Includes tycons/classes but we - op_ty_fvs = extractHsTyNames op_ty -- don't care about that - - check_in_op_ty clas_tyvar = checkRn (clas_tyvar `elemNameSet` op_ty_fvs) - (classTyVarNotInOpTyErr clas_tyvar sig) - in - mapRn check_in_op_ty clas_tyvars `thenRn_` - - returnRn (ClassOpSig op_name maybe_dm_name new_ty locn) +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} @@ -234,542 +274,449 @@ rnDecl (ClD (ClassDecl context cname tyvars sigs mbinds pragmas tname dname src_ %********************************************************* \begin{code} -rnDecl (InstD (InstDecl inst_ty mbinds uprags maybe_dfun src_loc)) - = pushSrcLocRn src_loc $ - rnHsSigType (text "an instance decl") inst_ty `thenRn` \ inst_ty' -> - +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 - -- NB meth_names can be qualified! - checkDupNames meth_doc meth_names `thenRn_` - rnMethodBinds mbinds `thenRn` \ mbinds' -> - let - binders = mkNameSet (map fst (bagToList (collectMonoBinders mbinds'))) - in - renameSigs NotTopLevel True binders uprags `thenRn` \ new_uprags -> - + -- The typechecker (not the renamer) checks that all + -- the bindings are for the right class let - -- We use the class name and the name of the first - -- type constructor the class is applied to. - (cl_nm, tycon_nm) = mkDictPrefix inst_ty' - - mkDictPrefix (MonoDictTy cl tys) = - case tys of - [] -> (c_nm, nilOccName ) - (ty:_) -> (c_nm, getInstHeadTy ty) - where - c_nm = nameOccName (getName cl) - - mkDictPrefix (HsPreForAllTy _ ty) = mkDictPrefix ty - mkDictPrefix (HsForAllTy _ _ ty) = mkDictPrefix ty -- can this - mkDictPrefix _ = (nilOccName, nilOccName) - - getInstHeadTy t - = case t of - MonoTyVar tv -> nameOccName (getName tv) - MonoTyApp t _ -> getInstHeadTy t - _ -> nilOccName - -- I cannot see how the rest of HsType constructors - -- can occur, but this isn't really a failure condition, - -- so we return silently. - - nilOccName = (VarOcc _NIL_) -- ToDo: add OccName constructor fun for this. + 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 + binders = collectHsBindBinders mbinds' + ok_sig = okInstDclSig (mkNameSet binders) in - newDfunName cl_nm tycon_nm maybe_dfun src_loc `thenRn` \ dfun_name -> - addOccurrenceName dfun_name `thenRn_` - -- The dfun is not optional, because we use its version number - -- to identify the version of the instance declaration + bindLocalNames binders (renameSigs ok_sig uprags) `thenM` \ uprags' -> - -- The typechecker checks that all the bindings are for the right class. - returnRn (InstD (InstDecl inst_ty' mbinds' new_uprags (Just dfun_name) src_loc)) - where - meth_doc = text "the bindings in an instance declaration" - meth_names = bagToList (collectMonoBinders mbinds) + returnM (InstDecl inst_ty' mbinds' uprags', + meth_fvs `plusFV` hsSigsFVs uprags' + `plusFV` extractHsTyNames inst_ty') \end{code} -%********************************************************* -%* * -\subsection{Default declarations} -%* * -%********************************************************* +For the method bindings in class and instance decls, we extend the +type variable environment iff -fglasgow-exts \begin{code} -rnDecl (DefD (DefaultDecl tys src_loc)) - = pushSrcLocRn src_loc $ - mapRn rnHsType tys `thenRn` \ tys' -> - lookupImplicitOccRn numClass_RDR `thenRn_` - returnRn (DefD (DefaultDecl tys' src_loc)) +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{Foreign declarations} -%* * -%********************************************************* - -\begin{code} -rnDecl (ForD (ForeignDecl name imp_exp ty ext_nm cconv src_loc)) - = pushSrcLocRn src_loc $ - lookupBndrRn name `thenRn` \ name' -> - (if is_import then - addImplicitOccRn name' - else - returnRn name') `thenRn_` - rnHsSigType fo_decl_msg ty `thenRn` \ ty' -> - -- hack: force the constructors of IO to be slurped in, - -- since we need 'em when desugaring a foreign decl. - addImplicitOccRn ioOkDataCon_NAME `thenRn_` - returnRn (ForD (ForeignDecl name' imp_exp ty' ext_nm cconv src_loc)) - where - fo_decl_msg = ptext SLIT("a foreign declaration") - is_import = - not (isDynamic ext_nm) && - case imp_exp of - FoImport _ -> True - _ -> False - -\end{code} %********************************************************* %* * -\subsection{Support code for type/data declarations} +\subsection{Rules} %* * %********************************************************* \begin{code} -rnDerivs :: Maybe [RdrName] -> RnMS s (Maybe [Name]) +rnHsRuleDecl (HsRule rule_name act vars lhs fv_lhs rhs fv_rhs) + = bindPatSigTyVarsFV (collectRuleBndrSigTys vars) $ -rnDerivs Nothing -- derivs not specified - = lookupImplicitOccRn evalClass_RDR `thenRn_` - returnRn Nothing + bindLocatedLocalsFV doc (map get_var vars) $ \ ids -> + mapFvRn rn_var (vars `zip` ids) `thenM` \ (vars', fv_vars) -> -rnDerivs (Just ds) - = lookupImplicitOccRn evalClass_RDR `thenRn_` - mapRn rn_deriv ds `thenRn` \ derivs -> - returnRn (Just derivs) + 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 + mappM (addErr . badRuleVar rule_name) bad_vars `thenM_` + returnM (HsRule rule_name act vars' lhs' fv_lhs' rhs' fv_rhs', + fv_vars `plusFV` fv_lhs' `plusFV` fv_rhs') where - rn_deriv clas - = lookupOccRn clas `thenRn` \ clas_name -> - - -- Now add extra "occurrences" for things that - -- the deriving mechanism will later need in order to - -- generate code for this class. - case lookupUFM derivingOccurrences clas_name of - Nothing -> addErrRn (derivingNonStdClassErr clas_name) `thenRn_` - returnRn clas_name - - Just occs -> mapRn lookupImplicitOccRn occs `thenRn_` - returnRn clas_name + doc = text "In the transformation rule" <+> ftext rule_name + + get_var (RuleBndr v) = v + get_var (RuleBndrSig v _) = v + + 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.) + +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 s RenamedConDecl -rnConDecl (ConDecl name cxt details locn) - = pushSrcLocRn locn $ - checkConName name `thenRn_` - lookupBndrRn name `thenRn` \ new_name -> - rnConDetails name locn details `thenRn` \ new_details -> - rnContext cxt `thenRn` \ new_context -> - returnRn (ConDecl new_name new_context new_details locn) - -rnConDetails con locn (VanillaCon tys) - = mapRn rnBangTy tys `thenRn` \ new_tys -> - returnRn (VanillaCon new_tys) - -rnConDetails con locn (InfixCon ty1 ty2) - = rnBangTy ty1 `thenRn` \ new_ty1 -> - rnBangTy ty2 `thenRn` \ new_ty2 -> - returnRn (InfixCon new_ty1 new_ty2) - -rnConDetails con locn (NewCon ty) - = rnHsType ty `thenRn` \ new_ty -> - returnRn (NewCon new_ty) - -rnConDetails con locn (RecCon fields) - = checkDupOrQualNames fld_doc field_names `thenRn_` - mapRn rnField fields `thenRn` \ new_fields -> - returnRn (RecCon new_fields) +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 - fld_doc = text "the fields of constructor" <> ppr con - field_names = [(fld, locn) | (flds, _) <- fields, fld <- flds] + checkl (L loc e) = check e -rnField (names, ty) - = mapRn lookupBndrRn names `thenRn` \ new_names -> - rnBangTy ty `thenRn` \ new_ty -> - returnRn (new_names, new_ty) + 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 -rnBangTy (Banged ty) - = rnHsType ty `thenRn` \ new_ty -> - returnRn (Banged new_ty) + checkl_e (L loc e) = check_e e -rnBangTy (Unbanged ty) - = rnHsType ty `thenRn` \ new_ty -> - returnRn (Unbanged new_ty) + check_e (HsVar v) = Nothing + check_e (HsPar e) = checkl_e e + check_e (HsLit e) = Nothing + check_e (HsOverLit e) = Nothing --- 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 + 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 + + checkl_es es = foldr (seqMaybe . checkl_e) Nothing es -checkConName name - = checkRn (isLexCon (occNameString (rdrNameOcc name))) - (badDataCon name) +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") + +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} %* * %********************************************************* -\begin{code} -rnHsSigType :: SDoc -> RdrNameHsType -> RnMS s RenamedHsType - -- rnHsSigType is used for source-language type signatures, - -- which use *implicit* universal quantification. - --- Given the signature C => T we universally quantify over FV(T) \ {in-scope-tyvars} --- --- We insist that the universally quantified type vars is a superset of FV(C) --- It follows that FV(T) is a superset of FV(C), so that the context constrains --- no type variables that don't appear free in the tau-type part. - -rnHsSigType doc_str full_ty@(HsPreForAllTy ctxt ty) -- From source code (no kinds on tyvars) - = getLocalNameEnv `thenRn` \ name_env -> - let - mentioned_tyvars = extractHsTyVars ty - forall_tyvars = filter (not . in_scope) mentioned_tyvars - in_scope tv = maybeToBool (lookupFM name_env tv) - - constrained_tyvars = extractHsCtxtTyVars ctxt - constrained_and_in_scope = filter in_scope constrained_tyvars - constrained_and_not_mentioned = filter (not . (`elem` mentioned_tyvars)) constrained_tyvars - - -- Zap the context if there's a problem, to avoid duplicate error message. - ctxt' | null constrained_and_in_scope && null constrained_and_not_mentioned = ctxt - | otherwise = [] - in - checkRn (null constrained_and_in_scope) - (ctxtErr1 sig_doc constrained_and_in_scope) `thenRn_` - checkRn (null constrained_and_not_mentioned) - (ctxtErr2 sig_doc constrained_and_not_mentioned ty) `thenRn_` - - (bindTyVarsRn sig_doc (map UserTyVar forall_tyvars) $ \ new_tyvars -> - rnContext ctxt' `thenRn` \ new_ctxt -> - rnHsType ty `thenRn` \ new_ty -> - returnRn (HsForAllTy new_tyvars new_ctxt new_ty) - ) - where - sig_doc = text "the type signature for" <+> doc_str - +@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. -rnHsSigType doc_str other_ty = rnHsType other_ty +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. -rnHsType :: RdrNameHsType -> RnMS s RenamedHsType -rnHsType (HsForAllTy tvs ctxt ty) -- From an interface file (tyvars may be kinded) - = rn_poly_help tvs ctxt ty +\begin{code} +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 + = do { tycon' <- lookupLocatedTopBndrRn tycon + ; checkTc (null (unLoc context)) (badGadtStupidTheta 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 full_ty@(HsPreForAllTy ctxt ty) -- A (context => ty) embedded in a type. - -- Universally quantify over tyvars in context - = getLocalNameEnv `thenRn` \ name_env -> - let - forall_tyvars = extractHsCtxtTyVars ctxt - in - rn_poly_help (map UserTyVar forall_tyvars) ctxt ty - -rnHsType (MonoTyVar tyvar) - = lookupOccRn tyvar `thenRn` \ tyvar' -> - returnRn (MonoTyVar tyvar') - -rnHsType (MonoFunTy ty1 ty2) - = andRn MonoFunTy (rnHsType ty1) (rnHsType ty2) - -rnHsType (MonoListTy _ ty) - = lookupImplicitOccRn listType_RDR `thenRn` \ tycon_name -> - rnHsType ty `thenRn` \ ty' -> - returnRn (MonoListTy tycon_name ty') - -rnHsType (MonoTupleTy _ tys) - = lookupImplicitOccRn (tupleType_RDR (length tys)) `thenRn` \ tycon_name -> - mapRn rnHsType tys `thenRn` \ tys' -> - returnRn (MonoTupleTy tycon_name tys') - -rnHsType (MonoTyApp ty1 ty2) - = rnHsType ty1 `thenRn` \ ty1' -> - rnHsType ty2 `thenRn` \ ty2' -> - returnRn (MonoTyApp ty1' ty2') - -rnHsType (MonoDictTy clas tys) - = lookupOccRn clas `thenRn` \ clas' -> - mapRn rnHsType tys `thenRn` \ tys' -> - returnRn (MonoDictTy clas' tys') - -rn_poly_help :: [HsTyVar RdrName] -- Universally quantified tyvars - -> RdrNameContext - -> RdrNameHsType - -> RnMS s RenamedHsType -rn_poly_help tyvars ctxt ty - = bindTyVarsRn sig_doc tyvars $ \ new_tyvars -> - rnContext ctxt `thenRn` \ new_ctxt -> - rnHsType ty `thenRn` \ new_ty -> - returnRn (HsForAllTy new_tyvars new_ctxt new_ty) where - sig_doc = text "a nested for-all type" -\end{code} + is_vanilla = case condecls of -- Yuk + [] -> True + L _ (ConDecl { con_res = ResTyH98 }) : _ -> True + other -> False + data_doc = text "In the data type declaration for" <+> quotes (ppr tycon) + con_names = map con_names_helper condecls -\begin{code} -rnContext :: RdrNameContext -> RnMS s RenamedContext + con_names_helper (L _ c) = con_name c -rnContext ctxt - = mapRn rn_ctxt ctxt `thenRn` \ result -> + 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 + syn_doc = text "In the declaration for type synonym" <+> quotes (ppr name) + +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 okClsDclSig 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 - (_, dup_asserts) = removeDups cmp_assert result - (alls, theta) = partition (\(c,_) -> c == allClass_NAME) result + sig_rdr_names_w_locs = [op | L _ (TypeSig op _) <- sigs] in + checkDupNames sig_doc sig_rdr_names_w_locs `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. - -- Check for duplicate assertions - -- If this isn't an error, then it ought to be: - mapRn (addWarnRn . dupClassAssertWarn theta) dup_asserts `thenRn_` - - -- Check for All constraining a non-type-variable - mapRn check_All alls `thenRn_` - - -- Done. Return a theta omitting all the "All" constraints. - -- They have done done their work by ensuring that we universally - -- quantify over their tyvar. - returnRn theta + -- 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_ctxt (clas, tys) - = -- Mini hack here. If the class is our pseudo-class "All", - -- then we don't want to record it as an occurrence, otherwise - -- we try to slurp it in later and it doesn't really exist at all. - -- Easiest thing is simply not to put it in the occurrence set. - lookupBndrRn clas `thenRn` \ clas_name -> - (if clas_name /= allClass_NAME then - addOccurrenceName clas_name - else - returnRn clas_name - ) `thenRn_` - mapRn rnHsType tys `thenRn` \ tys' -> - returnRn (clas_name, tys') - - - cmp_assert (c1,tys1) (c2,tys2) - = (c1 `compare` c2) `thenCmp` (cmpHsTypes compare tys1 tys2) - - check_All (c, [MonoTyVar _]) = returnRn () -- OK! - check_All assertion = addErrRn (wierdAllErr assertion) -\end{code} + 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 +badGadtStupidTheta tycon + = vcat [ptext SLIT("No context is allowed on a GADT-style data declaration"), + ptext SLIT("(You can put a context on each contructor, though.)")] +\end{code} %********************************************************* %* * -\subsection{IdInfo} +\subsection{Support code for type/data declarations} %* * %********************************************************* \begin{code} -rnIdInfo (HsStrictness strict) - = rnStrict strict `thenRn` \ strict' -> - returnRn (HsStrictness strict') - -rnIdInfo (HsUnfold inline expr) = rnCoreExpr expr `thenRn` \ expr' -> - returnRn (HsUnfold inline expr') -rnIdInfo (HsArity arity) = returnRn (HsArity arity) -rnIdInfo (HsUpdate update) = returnRn (HsUpdate update) -rnIdInfo (HsFBType fb) = returnRn (HsFBType fb) -rnIdInfo (HsArgUsage au) = returnRn (HsArgUsage au) -rnIdInfo (HsSpecialise tyvars tys expr) - = bindTyVarsRn doc tyvars $ \ tyvars' -> - rnCoreExpr expr `thenRn` \ expr' -> - mapRn rnHsType tys `thenRn` \ tys' -> - returnRn (HsSpecialise tyvars' tys' expr') +rnConDecls :: Name -> [LConDecl RdrName] -> RnM [LConDecl Name] +rnConDecls tycon condecls + = mappM (wrapLocM rnConDecl) condecls + +rnConDecl :: ConDecl RdrName -> RnM (ConDecl Name) +rnConDecl (ConDecl name expl tvs cxt details res_ty) + = do { addLocM checkConName name + + ; new_name <- lookupLocatedTopBndrRn name + ; name_env <- getLocalRdrEnv + + -- For H98 syntax, the tvs are the existential ones + -- For GADT syntax, the tvs are all the quantified tyvars + -- Hence the 'filter' in the ResTyH98 case only + ; let not_in_scope = not . (`elemLocalRdrEnv` name_env) . unLoc + arg_tys = hsConArgs details + implicit_tvs = case res_ty of + ResTyH98 -> filter not_in_scope $ + get_rdr_tvs arg_tys + ResTyGADT ty -> get_rdr_tvs (ty : arg_tys) + tvs' = case expl of + Explicit -> tvs + Implicit -> userHsTyVarBndrs implicit_tvs + + ; bindTyVarsRn doc tvs' $ \new_tyvars -> do + { new_context <- rnContext doc cxt + ; new_details <- rnConDetails doc details + ; new_res_ty <- rnConResult doc res_ty + ; let rv = ConDecl new_name expl new_tyvars new_context new_details new_res_ty + ; traceRn (text "****** - autrijus" <> ppr rv) + ; return rv } } where - doc = text "Specialise in interface pragma" - - -rnStrict (HsStrictnessInfo demands (Just (worker,cons))) - -- The sole purpose of the "cons" field is so that we can mark the constructors - -- needed to build the wrapper as "needed", so that their data type decl will be - -- slurped in. After that their usefulness is o'er, so we just put in the empty list. - = lookupOccRn worker `thenRn` \ worker' -> - mapRn lookupOccRn cons `thenRn_` - returnRn (HsStrictnessInfo demands (Just (worker',[]))) - --- Boring, but necessary for the type checker. -rnStrict (HsStrictnessInfo demands Nothing) = returnRn (HsStrictnessInfo demands Nothing) -rnStrict HsBottom = returnRn HsBottom -\end{code} - -UfCore expressions. - -\begin{code} -rnCoreExpr (UfVar v) - = lookupOccRn v `thenRn` \ v' -> - returnRn (UfVar v') - -rnCoreExpr (UfLit lit) = returnRn (UfLit lit) - -rnCoreExpr (UfCon con args) - = lookupOccRn con `thenRn` \ con' -> - mapRn rnCoreArg args `thenRn` \ args' -> - returnRn (UfCon con' args') - -rnCoreExpr (UfPrim prim args) - = rnCorePrim prim `thenRn` \ prim' -> - mapRn rnCoreArg args `thenRn` \ args' -> - returnRn (UfPrim prim' args') - -rnCoreExpr (UfApp fun arg) - = rnCoreExpr fun `thenRn` \ fun' -> - rnCoreArg arg `thenRn` \ arg' -> - returnRn (UfApp fun' arg') - -rnCoreExpr (UfCase scrut alts) - = rnCoreExpr scrut `thenRn` \ scrut' -> - rnCoreAlts alts `thenRn` \ alts' -> - returnRn (UfCase scrut' alts') - -rnCoreExpr (UfNote note expr) - = rnNote note `thenRn` \ note' -> - rnCoreExpr expr `thenRn` \ expr' -> - returnRn (UfNote note' expr') - -rnCoreExpr (UfLam bndr body) - = rnCoreBndr bndr $ \ bndr' -> - rnCoreExpr body `thenRn` \ body' -> - returnRn (UfLam bndr' body') - -rnCoreExpr (UfLet (UfNonRec bndr rhs) body) - = rnCoreExpr rhs `thenRn` \ rhs' -> - rnCoreBndr bndr $ \ bndr' -> - rnCoreExpr body `thenRn` \ body' -> - returnRn (UfLet (UfNonRec bndr' rhs') body') - -rnCoreExpr (UfLet (UfRec pairs) body) - = rnCoreBndrs bndrs $ \ bndrs' -> - mapRn rnCoreExpr rhss `thenRn` \ rhss' -> - rnCoreExpr body `thenRn` \ body' -> - returnRn (UfLet (UfRec (bndrs' `zip` rhss')) body') - where - (bndrs, rhss) = unzip pairs -\end{code} - -\begin{code} -rnCoreBndr (UfValBinder name ty) thing_inside - = rnHsType ty `thenRn` \ ty' -> - bindLocalsRn "unfolding value" [name] $ \ [name'] -> - thing_inside (UfValBinder name' ty') - -rnCoreBndr (UfTyBinder name kind) thing_inside - = bindLocalsRn "unfolding tyvar" [name] $ \ [name'] -> - thing_inside (UfTyBinder name' kind) - -rnCoreBndrs bndrs thing_inside -- Expect them all to be ValBinders - = mapRn rnHsType tys `thenRn` \ tys' -> - bindLocalsRn "unfolding value" names $ \ names' -> - thing_inside (zipWith UfValBinder names' tys') + doc = text "In the definition of data constructor" <+> quotes (ppr name) + get_rdr_tvs tys = extractHsRhoRdrTyVars cxt (noLoc (HsTupleTy Boxed tys)) + +rnConResult _ ResTyH98 = return ResTyH98 +rnConResult doc (ResTyGADT ty) = do + ty' <- rnHsSigType doc ty + return $ ResTyGADT ty' + +rnConDetails doc (PrefixCon tys) + = mappM (rnLHsType doc) tys `thenM` \ new_tys -> + returnM (PrefixCon new_tys) + +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 - names = map (\ (UfValBinder name _) -> name) bndrs - tys = map (\ (UfValBinder _ ty) -> ty) bndrs + field_names = [fld | (fld, _) <- fields] -rnCoreBndrNamess names thing_inside - = bindLocalsRn "unfolding value" names $ \ names' -> - thing_inside names' -\end{code} +rnField doc (name, ty) + = lookupLocatedTopBndrRn name `thenM` \ new_name -> + rnLHsType doc ty `thenM` \ new_ty -> + returnM (new_name, new_ty) -\begin{code} -rnCoreArg (UfVarArg v) = lookupOccRn v `thenRn` \ v' -> returnRn (UfVarArg v') -rnCoreArg (UfTyArg ty) = rnHsType ty `thenRn` \ ty' -> returnRn (UfTyArg ty') -rnCoreArg (UfLitArg lit) = returnRn (UfLitArg lit) - -rnCoreAlts (UfAlgAlts alts deflt) - = mapRn rn_alt alts `thenRn` \ alts' -> - rnCoreDefault deflt `thenRn` \ deflt' -> - returnRn (UfAlgAlts alts' deflt') - where - rn_alt (con, bndrs, rhs) = lookupOccRn con `thenRn` \ con' -> - bindLocalsRn "unfolding alt" bndrs $ \ bndrs' -> - rnCoreExpr rhs `thenRn` \ rhs' -> - returnRn (con', bndrs', rhs') - -rnCoreAlts (UfPrimAlts alts deflt) - = mapRn rn_alt alts `thenRn` \ alts' -> - rnCoreDefault deflt `thenRn` \ deflt' -> - returnRn (UfPrimAlts alts' deflt') - where - rn_alt (lit, rhs) = rnCoreExpr rhs `thenRn` \ rhs' -> - returnRn (lit, rhs') - -rnCoreDefault UfNoDefault = returnRn UfNoDefault -rnCoreDefault (UfBindDefault bndr rhs) = bindLocalsRn "unfolding default" [bndr] $ \ [bndr'] -> - rnCoreExpr rhs `thenRn` \ rhs' -> - returnRn (UfBindDefault bndr' rhs') - -rnNote (UfCoerce ty) - = rnHsType ty `thenRn` \ ty' -> - returnRn (UfCoerce ty') - -rnNote (UfSCC cc) = returnRn (UfSCC cc) -rnNote UfInlineCall = returnRn UfInlineCall +-- 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 -rnCorePrim (UfOtherOp op) - = lookupOccRn op `thenRn` \ op' -> - returnRn (UfOtherOp op') +checkConName name = checkErr (isRdrDataCon name) (badDataCon name) -rnCorePrim (UfCCallOp str casm gc arg_tys res_ty) - = mapRn rnHsType arg_tys `thenRn` \ arg_tys' -> - rnHsType res_ty `thenRn` \ res_ty' -> - returnRn (UfCCallOp str casm gc arg_tys' res_ty') +badDataCon name + = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)] \end{code} + %********************************************************* %* * -\subsection{Errors} +\subsection{Support code to rename types} %* * %********************************************************* \begin{code} -derivingNonStdClassErr clas - = hsep [ptext SLIT("non-standard class"), ppr clas, ptext SLIT("in deriving clause")] +rnFds :: SDoc -> [Located (FunDep RdrName)] -> RnM [Located (FunDep Name)] -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) +rnFds doc fds + = mappM (wrapLocM rn_fds) fds + where + rn_fds (tys1, tys2) + = rnHsTyVars doc tys1 `thenM` \ tys1' -> + rnHsTyVars doc tys2 `thenM` \ tys2' -> + returnM (tys1', tys2') -dupClassAssertWarn ctxt (assertion : dups) - = sep [hsep [ptext SLIT("Duplicate class assertion"), - quotes (pprClassAssertion assertion), - ptext SLIT("in the context:")], - nest 4 (pprContext ctxt)] +rnHsTyVars doc tvs = mappM (rnHsTyvar doc) tvs +rnHsTyvar doc tyvar = lookupOccRn tyvar +\end{code} -badDataCon name - = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)] -wierdAllErr assertion - = ptext SLIT("Mal-formed use of `All':") <+> pprClassAssertion assertion +%********************************************************* +%* * + Splices +%* * +%********************************************************* -ctxtErr1 doc tyvars - = hsep [ptext SLIT("Context constrains in-scope type variable(s)"), - pprQuotedList tyvars] - $$ - nest 4 (ptext SLIT("in") <+> doc) +Note [Splices] +~~~~~~~~~~~~~~ +Consider + f = ... + h = ...$(thing "f")... + +The splice can expand into literally anything, so when we do dependency +analysis we must assume that it might mention 'f'. So we simply treat +all locally-defined names as mentioned by any splice. This is terribly +brutal, but I don't see what else to do. For example, it'll mean +that every locally-defined thing will appear to be used, so no unused-binding +warnings. But if we miss the dependency, then we might typecheck 'h' before 'f', +and that will crash the type checker because 'f' isn't in scope. + +Currently, I'm not treating a splice as also mentioning every import, +which is a bit inconsistent -- but there are a lot of them. We might +thereby get some bogus unused-import warnings, but we won't crash the +type checker. Not very satisfactory really. -ctxtErr2 doc tyvars ty - = (ptext SLIT("Context constrains type variable(s)") - <+> pprQuotedList tyvars) - $$ - nest 4 (vcat [ptext SLIT("that do not appear in") <+> quotes (ppr ty), - ptext SLIT("in") <+> doc]) +\begin{code} +rnSplice :: HsSplice RdrName -> RnM (HsSplice Name, FreeVars) +rnSplice (HsSplice n expr) + = do { checkTH expr "splice" + ; loc <- getSrcSpanM + ; [n'] <- newLocalsRn [L loc n] + ; (expr', fvs) <- rnLExpr expr + + -- Ugh! See Note [Splices] above + ; lcl_rdr <- getLocalRdrEnv + ; gbl_rdr <- getGlobalRdrEnv + ; let gbl_names = mkNameSet [gre_name gre | gre <- globalRdrEnvElts gbl_rdr, + isLocalGRE gre] + lcl_names = mkNameSet (occEnvElts lcl_rdr) + + ; return (HsSplice n' expr', fvs `plusFV` lcl_names `plusFV` gbl_names) } + +#ifdef GHCI +checkTH e what = returnM () -- OK +#else +checkTH e what -- Raise an error in a stage-1 compiler + = addErr (vcat [ptext SLIT("Template Haskell") <+> text what <+> + ptext SLIT("illegal in a stage-1 compiler"), + nest 2 (ppr e)]) +#endif \end{code}