X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnSource.lhs;h=173810516cb5ec6b68196bde7ac51af1b2e6b89e;hb=f4c9d2b23bd63b48566e0ca3b13c8bdfc4cd0c0b;hp=b5386a3d1ab543975eaed852020c52c31e23cb12;hpb=0299e1a135c5805e09ed8e2271b3b17fc8a04869;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnSource.lhs b/ghc/compiler/rename/RnSource.lhs index b5386a3..1738105 100644 --- a/ghc/compiler/rename/RnSource.lhs +++ b/ghc/compiler/rename/RnSource.lhs @@ -4,49 +4,46 @@ \section[RnSource]{Main pass of renamer} \begin{code} -module RnSource ( rnTyClDecl, rnIfaceRuleDecl, rnInstDecl, rnSourceDecls, - ) where +module RnSource ( + rnSrcDecls, addTcgDUs, + rnTyClDecls, checkModDeprec, + rnBindGroups, rnBindGroupsAndThen, rnSplice + ) where #include "HsVersions.h" -import RnExpr import HsSyn -import HscTypes ( GlobalRdrEnv, AvailEnv ) -import RdrName ( RdrName, isRdrDataCon, elemRdrEnv ) -import RdrHsSyn ( RdrNameConDecl, RdrNameTyClDecl, - extractGenericPatTyVars - ) +import RdrName ( RdrName, isRdrDataCon, rdrNameOcc, elemLocalRdrEnv ) +import RdrHsSyn ( extractGenericPatTyVars ) import RnHsSyn -import HsCore - -import RnTypes ( rnHsType, rnHsSigType, rnHsTypeFVs, rnContext ) - -import RnBinds ( rnTopBinds, rnMethodBinds, renameSigs, renameSigsFVs ) -import RnEnv ( lookupTopBndrRn, lookupOccRn, lookupIfaceName, - lookupOrigNames, lookupSysBinder, newLocalsRn, - bindLocalsFVRn, bindPatSigTyVars, +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, - bindCoreLocalRn, bindCoreLocalsRn, bindLocalNames, - checkDupOrQualNames, checkDupNames, mapFvRn + bindLocalNames, newIPNameRn, + checkDupNames, mapFvRn, + unknownNameErr ) -import RnMonad +import TcRnMonad -import Class ( FunDep, DefMeth (..) ) -import DataCon ( dataConId ) -import Name ( Name, NamedThing(..) ) +import BasicTypes ( TopLevelFlag(..) ) +import HscTypes ( FixityEnv, FixItem(..), + Deprecations, Deprecs(..), DeprecTxt, plusDeprecs ) +import Class ( FunDep ) +import Name ( Name ) import NameSet -import PrelInfo ( derivableClassKeys ) -import PrelNames ( deRefStablePtrName, newStablePtrName, - bindIOName, returnIOName - ) -import TysWiredIn ( tupleCon ) -import List ( partition ) +import NameEnv import Outputable -import SrcLoc ( SrcLoc ) +import SrcLoc ( Located(..), unLoc, getLoc, noLoc ) import CmdLineOpts ( DynFlag(..) ) -- Warn of unused for-all'd tyvars -import Unique ( Uniquable(..) ) -import Maybes ( maybeToBool ) +import Maybes ( seqMaybe ) +import Maybe ( catMaybes, isNothing ) \end{code} @rnSourceDecl@ `renames' declarations. @@ -65,60 +62,237 @@ 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{Source code declarations} -%* * +%* * + Source-code fixity declarations +%* * %********************************************************* \begin{code} -rnSourceDecls :: GlobalRdrEnv -> AvailEnv -> LocalFixityEnv - -> [RdrNameHsDecl] - -> RnMG ([RenamedHsDecl], FreeVars) - -- The decls get reversed, but that's ok - -rnSourceDecls gbl_env avails local_fixity_env decls - = initRnMS gbl_env avails emptyRdrEnv local_fixity_env SourceMode (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) = rnSourceDecl d `thenRn` \(d', fvs') -> - go (fvs `plusFV` fvs') (d':ds') ds - - -rnSourceDecl :: RdrNameHsDecl -> RnMS (RenamedHsDecl, FreeVars) + 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 (rdrNameOcc (unLoc rdr_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} -rnSourceDecl (ValD binds) = rnTopBinds binds `thenRn` \ (new_binds, fvs) -> - returnRn (ValD new_binds, fvs) -rnSourceDecl (TyClD tycl_decl) - = rnTyClDecl tycl_decl `thenRn` \ new_decl -> - finishSourceTyClDecl tycl_decl new_decl `thenRn` \ (new_decl', fvs) -> - returnRn (TyClD new_decl', fvs `plusFV` tyClDeclFVs new_decl') +%********************************************************* +%* * + Source-code deprecations declarations +%* * +%********************************************************* -rnSourceDecl (InstD inst) - = rnInstDecl inst `thenRn` \ new_inst -> - finishSourceInstDecl inst new_inst `thenRn` \ (new_inst', fvs) -> - returnRn (InstD new_inst', fvs `plusFV` instDeclFVs new_inst') +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. -rnSourceDecl (RuleD rule) - = rnHsRuleDecl rule `thenRn` \ (new_rule, fvs) -> - returnRn (RuleD new_rule, fvs) +\begin{code} +rnSrcDeprecDecls :: [LDeprecDecl RdrName] -> RnM Deprecations +rnSrcDeprecDecls [] + = returnM NoDeprecs + +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} -rnSourceDecl (ForD ford) - = rnHsForeignDecl ford `thenRn` \ (new_ford, fvs) -> - returnRn (ForD new_ford, fvs) +%********************************************************* +%* * +\subsection{Source code declarations} +%* * +%********************************************************* -rnSourceDecl (DefD (DefaultDecl tys src_loc)) - = pushSrcLocRn src_loc $ - mapFvRn (rnHsTypeFVs doc_str) tys `thenRn` \ (tys', fvs) -> - returnRn (DefD (DefaultDecl tys' src_loc), fvs) +\begin{code} +rnDefaultDecl (DefaultDecl tys) + = mapFvRn (rnHsTypeFVs doc_str) tys `thenM` \ (tys', fvs) -> + returnM (DefaultDecl tys', fvs) where doc_str = text "In a `default' declaration" \end{code} +%********************************************************* +%* * + Bindings +%* * +%********************************************************* + +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. + +\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} + %********************************************************* %* * @@ -127,26 +301,20 @@ rnSourceDecl (DefD (DefaultDecl tys src_loc)) %********************************************************* \begin{code} -rnHsForeignDecl (ForeignImport name ty spec isDeprec src_loc) - = pushSrcLocRn src_loc $ - lookupTopBndrRn name `thenRn` \ name' -> - rnHsTypeFVs (fo_decl_msg name) ty `thenRn` \ (ty', fvs) -> - returnRn (ForeignImport name' ty' spec isDeprec src_loc, - fvs `plusFV` extras spec) - where - extras (CImport _ _ _ _ CWrapper) = mkFVs [newStablePtrName, - deRefStablePtrName, - bindIOName, returnIOName] - extras _ = emptyFVs - -rnHsForeignDecl (ForeignExport name ty spec isDeprec src_loc) - = pushSrcLocRn src_loc $ - lookupOccRn name `thenRn` \ name' -> - rnHsTypeFVs (fo_decl_msg name) ty `thenRn` \ (ty', fvs) -> - returnRn (ForeignExport name' ty' spec isDeprec src_loc, - mkFVs [bindIOName, returnIOName] `plusFV` fvs) - -fo_decl_msg name = ptext SLIT("The foreign declaration for") <+> ppr name +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} @@ -157,43 +325,24 @@ fo_decl_msg name = ptext SLIT("The foreign declaration for") <+> ppr name %********************************************************* \begin{code} -rnInstDecl (InstDecl inst_ty mbinds uprags maybe_dfun_rdr_name src_loc) +rnSrcInstDecl (InstDecl inst_ty mbinds uprags) -- Used for both source and interface file decls - = pushSrcLocRn src_loc $ - rnHsSigType (text "an instance decl") inst_ty `thenRn` \ inst_ty' -> - - (case maybe_dfun_rdr_name of - Nothing -> returnRn Nothing - Just dfun_rdr_name -> lookupIfaceName dfun_rdr_name `thenRn` \ dfun_name -> - returnRn (Just dfun_name) - ) `thenRn` \ maybe_dfun_name -> - - -- The typechecker checks that all the bindings are for the right class. - returnRn (InstDecl inst_ty' EmptyMonoBinds [] maybe_dfun_name src_loc) - --- Compare finishSourceTyClDecl -finishSourceInstDecl (InstDecl _ mbinds uprags _ _ ) - (InstDecl inst_ty _ _ maybe_dfun_name src_loc) - -- Used for both source decls only - = ASSERT( not (maybeToBool maybe_dfun_name) ) -- Source decl! + = 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 = collectLocatedMonoBinders mbinds - (inst_tyvars, (cls,_)) = getHsInstHead inst_ty + 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 - in - - -- Rename the bindings - -- NB meth_names can be qualified! - checkDupNames meth_doc meth_names `thenRn_` - extendTyVarEnvFVRn (map hsTyVarName inst_tyvars) ( rnMethodBinds cls [] mbinds - ) `thenRn` \ (mbinds', meth_fvs) -> - let - binders = collectMonoBinders mbinds' - binder_set = mkNameSet binders - in + ) `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 @@ -201,14 +350,30 @@ finishSourceInstDecl (InstDecl _ mbinds uprags _ _ ) -- works OK. -- -- But the (unqualified) method names are in scope - bindLocalNames binders ( - renameSigsFVs (okInstDclSig binder_set) uprags - ) `thenRn` \ (uprags', prag_fvs) -> + let + binders = collectHsBindBinders mbinds' + in + bindLocalNames binders (renameSigs uprags) `thenM` \ uprags' -> + checkSigs (okInstDclSig (mkNameSet binders)) uprags' `thenM_` + + returnM (InstDecl inst_ty' mbinds' uprags', + meth_fvs `plusFV` hsSigsFVs uprags' + `plusFV` extractHsTyNames inst_ty') +\end{code} - returnRn (InstDecl inst_ty mbinds' uprags' maybe_dfun_name src_loc, - meth_fvs `plusFV` prag_fvs) +For the method bindings in class and instance decls, we extend the +type variable environment iff -fglasgow-exts + +\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} @@ -216,44 +381,87 @@ finishSourceInstDecl (InstDecl _ mbinds uprags _ _ ) %********************************************************* \begin{code} -rnIfaceRuleDecl (IfaceRule rule_name act vars fn args rhs src_loc) - = pushSrcLocRn src_loc $ - lookupOccRn fn `thenRn` \ fn' -> - rnCoreBndrs vars $ \ vars' -> - mapRn rnCoreExpr args `thenRn` \ args' -> - rnCoreExpr rhs `thenRn` \ rhs' -> - returnRn (IfaceRule rule_name act vars' fn' args' rhs' src_loc) - -rnIfaceRuleDecl (IfaceRuleOut fn rule) -- Builtin rules come this way - = lookupOccRn fn `thenRn` \ fn' -> - returnRn (IfaceRuleOut fn' rule) - -rnHsRuleDecl (HsRule rule_name act vars lhs rhs src_loc) - = pushSrcLocRn src_loc $ - bindPatSigTyVars (collectRuleBndrSigTys vars) $ - - 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 (HsRule rule_name act 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 "In the transformation rule" <+> ptext rule_name + 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) = rnHsTypeFVs 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.) + +NB: if you add new cases here, make sure you add new ones to TcRule.ruleLhsTvs + +\begin{code} +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 + checkl (L loc e) = check e + + 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 + + checkl_e (L loc e) = check_e e + + check_e (HsVar v) = Nothing + check_e (HsPar e) = checkl_e e + check_e (HsLit e) = Nothing + check_e (HsOverLit e) = Nothing + + 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 + +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} @@ -277,141 +485,99 @@ and then go over it again to rename the tyvars! However, we can also do some scoping checks at the same time. \begin{code} -rnTyClDecl (IfaceSig {tcdName = name, tcdType = ty, tcdIdInfo = id_infos, tcdLoc = loc}) - = pushSrcLocRn loc $ - lookupTopBndrRn name `thenRn` \ name' -> - rnHsType doc_str ty `thenRn` \ ty' -> - mapRn rnIdInfo id_infos `thenRn` \ id_infos' -> - returnRn (IfaceSig {tcdName = name', tcdType = ty', tcdIdInfo = id_infos', tcdLoc = loc}) - where - doc_str = text "In the interface signature for" <+> quotes (ppr name) - -rnTyClDecl (ForeignType {tcdName = name, tcdFoType = fo_type, tcdExtName = ext_name, tcdLoc = loc}) - = pushSrcLocRn loc $ - lookupTopBndrRn name `thenRn` \ name' -> - returnRn (ForeignType {tcdName = name', tcdFoType = fo_type, tcdExtName = ext_name, tcdLoc = loc}) - -rnTyClDecl (TyData {tcdND = new_or_data, tcdCtxt = context, tcdName = tycon, - tcdTyVars = tyvars, tcdCons = condecls, tcdNCons = nconstrs, - tcdDerivs = derivs, tcdLoc = src_loc, tcdSysNames = sys_names}) - = pushSrcLocRn src_loc $ - lookupTopBndrRn tycon `thenRn` \ tycon' -> +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' -> - rnContext data_doc context `thenRn` \ context' -> - rn_derivs derivs `thenRn` \ derivs' -> - checkDupOrQualNames data_doc con_names `thenRn_` + 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) } - -- Check that there's at least one condecl, - -- or else we're reading an interface file, or -fglasgow-exts - (if null condecls then - doptRn Opt_GlasgowExts `thenRn` \ glaExts -> - getModeRn `thenRn` \ mode -> - checkRn (glaExts || isInterfaceMode mode) - (emptyConDeclsErr tycon) - else returnRn () - ) `thenRn_` - - mapRn rnConDecl condecls `thenRn` \ condecls' -> - mapRn lookupSysBinder sys_names `thenRn` \ sys_names' -> - returnRn (TyData {tcdND = new_or_data, tcdCtxt = context', tcdName = tycon', - tcdTyVars = tyvars', tcdCons = condecls', tcdNCons = nconstrs, - tcdDerivs = derivs', tcdLoc = src_loc, tcdSysNames = sys_names'}) where + is_vanilla = case condecls of -- Yuk + [] -> True + L _ (ConDecl {}) : _ -> True + other -> False + data_doc = text "In the data type declaration for" <+> quotes (ppr tycon) - con_names = map conDeclName condecls + con_names = map con_names_helper condecls - rn_derivs Nothing = returnRn Nothing - rn_derivs (Just ds) = rnContext data_doc ds `thenRn` \ ds' -> returnRn (Just ds') + con_names_helper (L _ (ConDecl n _ _ _)) = n + con_names_helper (L _ (GadtDecl n _)) = n + + rn_derivs Nothing = returnM (Nothing, emptyFVs) + rn_derivs (Just ds) = rnLHsTypes data_doc ds `thenM` \ ds' -> + returnM (Just ds', extractHsTyNames_s ds') -rnTyClDecl (TySynonym {tcdName = name, tcdTyVars = tyvars, tcdSynRhs = ty, tcdLoc = src_loc}) - = pushSrcLocRn src_loc $ - lookupTopBndrRn name `thenRn` \ name' -> +rnTyClDecl (TySynonym {tcdLName = name, tcdTyVars = tyvars, tcdSynRhs = ty}) + = lookupLocatedTopBndrRn name `thenM` \ name' -> bindTyVarsRn syn_doc tyvars $ \ tyvars' -> - rnHsType syn_doc ty `thenRn` \ ty' -> - returnRn (TySynonym {tcdName = name', tcdTyVars = tyvars', tcdSynRhs = ty', tcdLoc = src_loc}) + 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, tcdName = cname, +rnTyClDecl (ClassDecl {tcdCtxt = context, tcdLName = cname, tcdTyVars = tyvars, tcdFDs = fds, tcdSigs = sigs, - tcdSysNames = names, tcdLoc = src_loc}) - -- Used for both source and interface file decls - = pushSrcLocRn src_loc $ - - lookupTopBndrRn 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! - mapRn lookupSysBinder names `thenRn` \ names' -> - - -- Tyvars scope over bindings and context - bindTyVarsRn cls_doc tyvars $ \ tyvars' -> - - -- Check the superclasses - rnContext cls_doc context `thenRn` \ context' -> + tcdMeths = mbinds}) + = lookupLocatedTopBndrRn cname `thenM` \ cname' -> - -- Check the functional dependencies - rnFds cls_doc fds `thenRn` \ fds' -> + -- 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 - (op_sigs, non_op_sigs) = partition isClassOpSig sigs - sig_rdr_names_w_locs = [(op,locn) | ClassOpSig op _ _ locn <- sigs] + sig_rdr_names_w_locs = [op | L _ (Sig op _) <- sigs] in - checkDupOrQualNames sig_doc sig_rdr_names_w_locs `thenRn_` - mapRn (rnClassOp cname' fds') op_sigs `thenRn` \ sigs' -> - let - binders = mkNameSet [ nm | (ClassOpSig nm _ _ _) <- sigs' ] - in - renameSigs (okClsDclSig binders) non_op_sigs `thenRn` \ non_ops' -> - + 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. - returnRn (ClassDecl { tcdCtxt = context', tcdName = cname', tcdTyVars = tyvars', - tcdFDs = fds', tcdSigs = non_ops' ++ sigs', tcdMeths = Nothing, - tcdSysNames = names', tcdLoc = src_loc}) - where - cls_doc = text "In the declaration for class" <+> ppr cname - sig_doc = text "In the signatures for class" <+> ppr cname - -rnClassOp clas clas_fds sig@(ClassOpSig op dm_stuff ty locn) - = pushSrcLocRn locn $ - lookupTopBndrRn op `thenRn` \ op_name -> - - -- Check the signature - rnHsSigType (quotes (ppr op)) ty `thenRn` \ new_ty -> - - -- Make the default-method name - (case dm_stuff of - DefMeth dm_rdr_name - -> -- Imported class that has a default method decl - -- See comments with tname, snames, above - lookupSysBinder dm_rdr_name `thenRn` \ dm_name -> - returnRn (DefMeth dm_name) - -- 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 - - GenDefMeth -> returnRn GenDefMeth - NoDefMeth -> returnRn NoDefMeth - ) `thenRn` \ dm_stuff' -> - - returnRn (ClassOpSig op_name dm_stuff' new_ty locn) - -finishSourceTyClDecl :: RdrNameTyClDecl -> RenamedTyClDecl -> RnMS (RenamedTyClDecl, FreeVars) - -- Used for source file decls only - -- Renames the default-bindings of a class decl -finishSourceTyClDecl (ClassDecl {tcdMeths = Just mbinds, tcdLoc = src_loc}) -- Get mbinds from here - rn_cls_decl@(ClassDecl {tcdName = cls, tcdTyVars = tyvars}) -- Everything else is here - -- There are some default-method bindings (abeit possibly empty) so - -- this is a source-code class declaration - = -- The newLocals call is tiresome: given a generic class decl + -- The newLocals call is tiresome: given a generic class decl -- class C a where -- op :: a -> a -- op {| x+y |} (Inl a) = ... @@ -419,27 +585,32 @@ finishSourceTyClDecl (ClassDecl {tcdMeths = Just mbinds, tcdLoc = src_loc}) -- G -- 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. - -- Hence the - pushSrcLocRn src_loc $ - extendTyVarEnvFVRn (map hsTyVarName tyvars) $ - getLocalNameEnv `thenRn` \ name_env -> - let - meth_rdr_names_w_locs = collectLocatedMonoBinders mbinds - gen_rdr_tyvars_w_locs = [(tv,src_loc) | tv <- extractGenericPatTyVars mbinds, - not (tv `elemRdrEnv` name_env)] - in - checkDupOrQualNames meth_doc meth_rdr_names_w_locs `thenRn_` - newLocalsRn gen_rdr_tyvars_w_locs `thenRn` \ gen_tyvars -> - rnMethodBinds cls gen_tyvars mbinds `thenRn` \ (mbinds', meth_fvs) -> - returnRn (rn_cls_decl {tcdMeths = Just mbinds'}, meth_fvs) + 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 - meth_doc = text "In the default-methods for class" <+> ppr (tcdName rn_cls_decl) - -finishSourceTyClDecl _ tycl_decl = returnRn (tycl_decl, emptyFVs) - -- Not a class declaration + 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{Support code for type/data declarations} @@ -447,49 +618,57 @@ finishSourceTyClDecl _ tycl_decl = returnRn (tycl_decl, emptyFVs) %********************************************************* \begin{code} -conDeclName :: RdrNameConDecl -> (RdrName, SrcLoc) -conDeclName (ConDecl n _ _ _ _ l) = (n,l) - -rnConDecl :: RdrNameConDecl -> RnMS RenamedConDecl -rnConDecl (ConDecl name wkr tvs cxt details locn) - = pushSrcLocRn locn $ - checkConName name `thenRn_` - lookupTopBndrRn name `thenRn` \ new_name -> +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 - lookupSysBinder wkr `thenRn` \ new_wkr -> - -- See comments with ClassDecl +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 `thenRn` \ new_context -> - rnConDetails doc locn details `thenRn` \ new_details -> - returnRn (ConDecl new_name new_wkr new_tyvars new_context new_details locn) + rnContext doc cxt `thenM` \ new_context -> + rnConDetails doc details `thenM` \ new_details -> + returnM (ConDecl new_name new_tyvars new_context new_details) + where + doc = text "In the definition of data constructor" <+> quotes (ppr name) + +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 "In the definition of data constructor" <+> quotes (ppr name) -rnConDetails doc locn (VanillaCon tys) - = mapRn (rnBangTy doc) tys `thenRn` \ new_tys -> - returnRn (VanillaCon new_tys) +rnConDetails doc (PrefixCon tys) + = mappM (rnLHsType doc) tys `thenM` \ new_tys -> + returnM (PrefixCon new_tys) -rnConDetails doc locn (InfixCon ty1 ty2) - = rnBangTy doc ty1 `thenRn` \ new_ty1 -> - rnBangTy doc ty2 `thenRn` \ new_ty2 -> - returnRn (InfixCon new_ty1 new_ty2) +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 locn (RecCon fields) - = checkDupOrQualNames doc field_names `thenRn_` - mapRn (rnField doc) fields `thenRn` \ new_fields -> - returnRn (RecCon new_fields) +rnConDetails doc (RecCon fields) + = checkDupNames doc field_names `thenM_` + mappM (rnField doc) fields `thenM` \ new_fields -> + returnM (RecCon new_fields) where - field_names = [(fld, locn) | (flds, _) <- fields, fld <- flds] - -rnField doc (names, ty) - = mapRn lookupTopBndrRn names `thenRn` \ new_names -> - rnBangTy doc ty `thenRn` \ new_ty -> - returnRn (new_names, new_ty) + field_names = [fld | (fld, _) <- fields] -rnBangTy doc (BangType s ty) - = rnHsType doc ty `thenRn` \ new_ty -> - returnRn (BangType s new_ty) +rnField doc (name, ty) + = lookupLocatedTopBndrRn name `thenM` \ new_name -> + rnLHsType doc ty `thenM` \ new_ty -> + returnM (new_name, new_ty) -- This data decl will parse OK -- data T = a Int @@ -501,9 +680,14 @@ rnBangTy doc (BangType s ty) -- data T = :% Int Int -- from interface files, which always print in prefix form -checkConName name - = checkRn (isRdrDataCon name) - (badDataCon name) +checkConName name = checkErr (isRdrDataCon name) (badDataCon name) + +badDataCon name + = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)] + +emptyConDeclsErr tycon + = sep [quotes (ppr tycon) <+> ptext SLIT("has no constructors"), + nest 4 (ptext SLIT("(-fglasgow-exts permits this)"))] \end{code} @@ -514,200 +698,33 @@ checkConName name %********************************************************* \begin{code} -rnFds :: SDoc -> [FunDep RdrName] -> RnMS [FunDep Name] +rnFds :: SDoc -> [Located (FunDep RdrName)] -> RnM [Located (FunDep Name)] rnFds doc fds - = mapRn rn_fds fds + = mappM (wrapLocM rn_fds) fds where rn_fds (tys1, tys2) - = rnHsTyVars doc tys1 `thenRn` \ tys1' -> - rnHsTyVars doc tys2 `thenRn` \ tys2' -> - returnRn (tys1', tys2') + = rnHsTyVars doc tys1 `thenM` \ tys1' -> + rnHsTyVars doc tys2 `thenM` \ tys2' -> + returnM (tys1', tys2') -rnHsTyVars doc tvs = mapRn (rnHsTyvar doc) tvs +rnHsTyVars doc tvs = mappM (rnHsTyvar doc) tvs rnHsTyvar doc tyvar = lookupOccRn tyvar \end{code} -%********************************************************* -%* * -\subsection{IdInfo} -%* * -%********************************************************* - -\begin{code} -rnIdInfo (HsWorker worker arity) - = lookupOccRn worker `thenRn` \ worker' -> - returnRn (HsWorker worker' arity) - -rnIdInfo (HsUnfold inline expr) = rnCoreExpr expr `thenRn` \ expr' -> - returnRn (HsUnfold inline expr') -rnIdInfo (HsStrictness str) = returnRn (HsStrictness str) -rnIdInfo (HsArity arity) = returnRn (HsArity arity) -rnIdInfo HsNoCafRefs = returnRn HsNoCafRefs -\end{code} - -@UfCore@ expressions. - -\begin{code} -rnCoreExpr (UfType ty) - = rnHsType (text "unfolding type") ty `thenRn` \ ty' -> - returnRn (UfType ty') -rnCoreExpr (UfVar v) - = lookupOccRn v `thenRn` \ v' -> - returnRn (UfVar v') - -rnCoreExpr (UfLit l) - = returnRn (UfLit l) - -rnCoreExpr (UfLitLit l ty) - = rnHsType (text "litlit") ty `thenRn` \ ty' -> - returnRn (UfLitLit l ty') - -rnCoreExpr (UfFCall cc ty) - = rnHsType (text "ccall") ty `thenRn` \ ty' -> - returnRn (UfFCall cc ty') - -rnCoreExpr (UfTuple (HsTupCon _ boxity arity) args) - = mapRn rnCoreExpr args `thenRn` \ args' -> - returnRn (UfTuple (HsTupCon tup_name boxity arity) args') - where - tup_name = getName (dataConId (tupleCon boxity arity)) - -- Get the *worker* name and use that - -rnCoreExpr (UfApp fun arg) - = rnCoreExpr fun `thenRn` \ fun' -> - rnCoreExpr arg `thenRn` \ arg' -> - returnRn (UfApp fun' arg') - -rnCoreExpr (UfCase scrut bndr alts) - = rnCoreExpr scrut `thenRn` \ scrut' -> - bindCoreLocalRn bndr $ \ bndr' -> - mapRn rnCoreAlt alts `thenRn` \ alts' -> - returnRn (UfCase scrut' bndr' 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 doc ty `thenRn` \ ty' -> - bindCoreLocalRn name $ \ name' -> - thing_inside (UfValBinder name' ty') - where - doc = text "unfolding id" - -rnCoreBndr (UfTyBinder name kind) thing_inside - = bindCoreLocalRn 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 `thenRn` \ con' -> - bindCoreLocalsRn bndrs $ \ bndrs' -> - rnCoreExpr rhs `thenRn` \ rhs' -> - returnRn (con', bndrs', rhs') - -rnNote (UfCoerce ty) - = rnHsType (text "unfolding coerce") ty `thenRn` \ ty' -> - returnRn (UfCoerce ty') - -rnNote (UfSCC cc) = returnRn (UfSCC cc) -rnNote UfInlineCall = returnRn UfInlineCall -rnNote UfInlineMe = returnRn UfInlineMe - - -rnUfCon UfDefault - = returnRn UfDefault - -rnUfCon (UfTupleAlt (HsTupCon _ boxity arity)) - = returnRn (UfTupleAlt (HsTupCon tup_name boxity arity)) - where - tup_name = getName (tupleCon boxity arity) - -rnUfCon (UfDataAlt con) - = lookupOccRn con `thenRn` \ con' -> - returnRn (UfDataAlt con') - -rnUfCon (UfLitAlt lit) - = returnRn (UfLitAlt lit) - -rnUfCon (UfLitLitAlt lit ty) - = rnHsType (text "litlit") ty `thenRn` \ ty' -> - returnRn (UfLitLitAlt lit ty') -\end{code} - -%********************************************************* -%* * -\subsection{Rule shapes} -%* * %********************************************************* - -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 - where - check (OpApp _ op _ _) = check op - check (HsApp e1 e2) = check e1 - check (HsVar v) | v `notElem` foralls = True - check other = False -\end{code} - - -%********************************************************* -%* * -\subsection{Errors} -%* * +%* * + Splices +%* * %********************************************************* \begin{code} -badDataCon name - = hsep [ptext SLIT("Illegal data constructor name"), quotes (ppr name)] - -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") <+> doubleQuotes (ptext name) <> colon, - ptext SLIT("Forall'd variable") <+> quotes (ppr var) <+> - ptext SLIT("does not appear on left hand side")] - -emptyConDeclsErr tycon - = sep [quotes (ppr tycon) <+> ptext SLIT("has no constructors"), - nest 4 (ptext SLIT("(-fglasgow-exts permits this)"))] +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}