X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnExpr.lhs;h=b1481e30f5350862ba40e5d32b19421a7e2bc4e5;hb=b44c6881743abf8f4c3c0612c482ede8b835ac37;hp=b5b5036654b942289c27b8a34f1a8dbada4f76f9;hpb=fe69f3c1d6062b90635963aa414c33951bf18427;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnExpr.lhs b/ghc/compiler/rename/RnExpr.lhs index b5b5036..b1481e3 100644 --- a/ghc/compiler/rename/RnExpr.lhs +++ b/ghc/compiler/rename/RnExpr.lhs @@ -11,154 +11,54 @@ free variables. \begin{code} module RnExpr ( - rnMatch, rnGRHSs, rnPat, rnExpr, rnExprs, + rnMatch, rnGRHSs, rnExpr, rnExprs, rnStmts, checkPrecMatch ) where #include "HsVersions.h" -import {-# SOURCE #-} RnBinds ( rnBinds ) -import {-# SOURCE #-} RnSource ( rnHsSigType, rnHsType ) +import {-# SOURCE #-} RnSource ( rnSrcDecls, rnBindsAndThen, rnBinds ) + +-- RnSource imports RnBinds.rnTopMonoBinds, RnExpr.rnExpr +-- RnBinds imports RnExpr.rnMatch, etc +-- RnExpr imports [boot] RnSource.rnSrcDecls, RnSource.rnBinds import HsSyn import RdrHsSyn import RnHsSyn -import RnMonad +import TcRnMonad import RnEnv -import RnIfaces ( lookupFixityRn ) -import CmdLineOpts ( opt_GlasgowExts, opt_IgnoreAsserts ) -import BasicTypes ( Fixity(..), FixityDirection(..), defaultFixity, negateFixity, negatePrecedence ) -import PrelInfo ( numClass_RDR, fractionalClass_RDR, eqClass_RDR, - ccallableClass_RDR, creturnableClass_RDR, - monadClass_RDR, enumClass_RDR, ordClass_RDR, - ratioDataCon_RDR, negate_RDR, assertErr_RDR, - ioDataCon_RDR, addr2Integer_RDR, - foldr_RDR, build_RDR - ) -import TysPrim ( charPrimTyCon, addrPrimTyCon, intPrimTyCon, - floatPrimTyCon, doublePrimTyCon - ) -import Name ( nameUnique, isLocallyDefined, NamedThing(..) - , mkSysLocalName, nameSrcLoc - ) +import RnNames ( importsFromLocalDecls ) +import RnTypes ( rnHsTypeFVs, rnPat, litFVs, rnOverLit, rnPatsAndThen, + dupFieldErr, precParseErr, sectionPrecErr, patSigErr, checkTupSize ) +import CmdLineOpts ( DynFlag(..), opt_IgnoreAsserts ) +import BasicTypes ( Fixity(..), FixityDirection(..), IPName(..), + defaultFixity, negateFixity, compareFixity ) +import PrelNames ( hasKey, assertIdKey, + foldrName, buildName, + cCallableClassName, cReturnableClassName, + enumClassName, + splitName, fstName, sndName, ioDataConName, + replicatePName, mapPName, filterPName, + crossPName, zipPName, toPName, + enumFromToPName, enumFromThenToPName, assertErrorName, + negateName, monadNames, mfixName ) +#ifdef GHCI +import DsMeta ( qTyConName ) +#endif +import Name ( Name, nameOccName ) import NameSet +import UnicodeUtil ( stringToUtf8 ) import UniqFM ( isNullUFM ) -import FiniteMap ( elemFM ) -import UniqSet ( emptyUniqSet, UniqSet ) -import Unique ( hasKey, assertIdKey ) -import Util ( removeDups ) -import ListSetOps ( unionLists ) -import Maybes ( maybeToBool ) +import UniqSet ( emptyUniqSet ) +import Util ( isSingleton ) +import List ( intersectBy, unzip4 ) +import ListSetOps ( removeDups ) import Outputable -import Literal ( inIntRange, tARGET_MAX_INT ) -import RdrName ( mkSrcUnqual ) -import OccName ( varName ) +import FastString \end{code} -********************************************************* -* * -\subsection{Patterns} -* * -********************************************************* - -\begin{code} -rnPat :: RdrNamePat -> RnMS (RenamedPat, FreeVars) - -rnPat WildPatIn = returnRn (WildPatIn, emptyFVs) - -rnPat (VarPatIn name) - = lookupBndrRn name `thenRn` \ vname -> - returnRn (VarPatIn vname, emptyFVs) - -rnPat (SigPatIn pat ty) - | opt_GlasgowExts - = rnPat pat `thenRn` \ (pat', fvs1) -> - rnHsType doc ty `thenRn` \ (ty', fvs2) -> - returnRn (SigPatIn pat' ty', fvs1 `plusFV` fvs2) - - | otherwise - = addErrRn (patSigErr ty) `thenRn_` - rnPat pat - where - doc = text "a pattern type-signature" - -rnPat (LitPatIn lit) - = litOccurrence lit `thenRn` \ fvs1 -> - lookupOrigName eqClass_RDR `thenRn` \ eq -> -- Needed to find equality on pattern - returnRn (LitPatIn lit, fvs1 `addOneFV` eq) - -rnPat (LazyPatIn pat) - = rnPat pat `thenRn` \ (pat', fvs) -> - returnRn (LazyPatIn pat', fvs) - -rnPat (AsPatIn name pat) - = rnPat pat `thenRn` \ (pat', fvs) -> - lookupBndrRn name `thenRn` \ vname -> - returnRn (AsPatIn vname pat', fvs) - -rnPat (ConPatIn con pats) - = lookupOccRn con `thenRn` \ con' -> - mapFvRn rnPat pats `thenRn` \ (patslist, fvs) -> - returnRn (ConPatIn con' patslist, fvs `addOneFV` con') - -rnPat (ConOpPatIn pat1 con _ pat2) - = rnPat pat1 `thenRn` \ (pat1', fvs1) -> - lookupOccRn con `thenRn` \ con' -> - rnPat pat2 `thenRn` \ (pat2', fvs2) -> - - getModeRn `thenRn` \ mode -> - -- See comments with rnExpr (OpApp ...) - (case mode of - InterfaceMode -> returnRn (ConOpPatIn pat1' con' defaultFixity pat2') - SourceMode -> lookupFixityRn con' `thenRn` \ fixity -> - mkConOpPatRn pat1' con' fixity pat2' - ) `thenRn` \ pat' -> - returnRn (pat', fvs1 `plusFV` fvs2 `addOneFV` con') - --- Negated patters can only be literals, and they are dealt with --- by negating the literal at compile time, not by using the negation --- operation in Num. So we don't need to make an implicit reference --- to negate_RDR. -rnPat neg@(NegPatIn pat) - = checkRn (valid_neg_pat pat) (negPatErr neg) - `thenRn_` - rnPat pat `thenRn` \ (pat', fvs) -> - returnRn (NegPatIn pat', fvs) - where - valid_neg_pat (LitPatIn (HsInt _)) = True - valid_neg_pat (LitPatIn (HsIntPrim _)) = True - valid_neg_pat (LitPatIn (HsFrac _)) = True - valid_neg_pat (LitPatIn (HsFloatPrim _)) = True - valid_neg_pat (LitPatIn (HsDoublePrim _)) = True - valid_neg_pat _ = False - -rnPat (ParPatIn pat) - = rnPat pat `thenRn` \ (pat', fvs) -> - returnRn (ParPatIn pat', fvs) - -rnPat (NPlusKPatIn name lit) - = litOccurrence lit `thenRn` \ fvs -> - lookupOrigName ordClass_RDR `thenRn` \ ord -> - lookupBndrRn name `thenRn` \ name' -> - returnRn (NPlusKPatIn name' lit, fvs `addOneFV` ord) - -rnPat (ListPatIn pats) - = mapFvRn rnPat pats `thenRn` \ (patslist, fvs) -> - returnRn (ListPatIn patslist, fvs `addOneFV` listTyCon_name) - -rnPat (TuplePatIn pats boxed) - = mapFvRn rnPat pats `thenRn` \ (patslist, fvs) -> - returnRn (TuplePatIn patslist boxed, fvs `addOneFV` tycon_name) - where - tycon_name = tupleTyCon_name boxed (length pats) - -rnPat (RecPatIn con rpats) - = lookupOccRn con `thenRn` \ con' -> - rnRpats rpats `thenRn` \ (rpats', fvs) -> - returnRn (RecPatIn con' rpats', fvs `addOneFV` con') -\end{code} - ************************************************************************ * * \subsection{Match} @@ -166,52 +66,36 @@ rnPat (RecPatIn con rpats) ************************************************************************ \begin{code} -rnMatch :: RdrNameMatch -> RnMS (RenamedMatch, FreeVars) - -rnMatch match@(Match _ pats maybe_rhs_sig grhss) - = pushSrcLocRn (getMatchLoc match) $ +rnMatch :: HsMatchContext Name -> RdrNameMatch -> RnM (RenamedMatch, FreeVars) - -- Find the universally quantified type variables - -- in the pattern type signatures - getLocalNameEnv `thenRn` \ name_env -> - let - tyvars_in_sigs = rhs_sig_tyvars `unionLists` tyvars_in_pats - rhs_sig_tyvars = case maybe_rhs_sig of - Nothing -> [] - Just ty -> extractHsTyRdrTyVars ty - tyvars_in_pats = extractPatsTyVars pats - forall_tyvars = filter (not . (`elemFM` name_env)) tyvars_in_sigs - doc_sig = text "a pattern type-signature" - doc_pats = text "in a pattern match" - in - bindTyVarsFVRn doc_sig (map UserTyVar forall_tyvars) $ \ sig_tyvars -> - - -- Note that we do a single bindLocalsRn for all the - -- matches together, so that we spot the repeated variable in - -- f x x = 1 - bindLocalsFVRn doc_pats (collectPatsBinders pats) $ \ new_binders -> +rnMatch ctxt match@(Match pats maybe_rhs_sig grhss) + = addSrcLoc (getMatchLoc match) $ - mapFvRn rnPat pats `thenRn` \ (pats', pat_fvs) -> - rnGRHSs grhss `thenRn` \ (grhss', grhss_fvs) -> + -- Deal with the rhs type signature + bindPatSigTyVars rhs_sig_tys $ + doptM Opt_GlasgowExts `thenM` \ opt_GlasgowExts -> (case maybe_rhs_sig of - Nothing -> returnRn (Nothing, emptyFVs) - Just ty | opt_GlasgowExts -> rnHsType doc_sig ty `thenRn` \ (ty', ty_fvs) -> - returnRn (Just ty', ty_fvs) - | otherwise -> addErrRn (patSigErr ty) `thenRn_` - returnRn (Nothing, emptyFVs) - ) `thenRn` \ (maybe_rhs_sig', ty_fvs) -> - - let - binder_set = mkNameSet new_binders - unused_binders = nameSetToList (binder_set `minusNameSet` grhss_fvs) - all_fvs = grhss_fvs `plusFV` pat_fvs `plusFV` ty_fvs - in - warnUnusedMatches unused_binders `thenRn_` - - returnRn (Match sig_tyvars pats' maybe_rhs_sig' grhss', all_fvs) - -- The bindLocals and bindTyVars will remove the bound FVs + Nothing -> returnM (Nothing, emptyFVs) + Just ty | opt_GlasgowExts -> rnHsTypeFVs doc_sig ty `thenM` \ (ty', ty_fvs) -> + returnM (Just ty', ty_fvs) + | otherwise -> addErr (patSigErr ty) `thenM_` + returnM (Nothing, emptyFVs) + ) `thenM` \ (maybe_rhs_sig', ty_fvs) -> + + -- Now the main event + rnPatsAndThen ctxt pats $ \ pats' -> + rnGRHSs ctxt grhss `thenM` \ (grhss', grhss_fvs) -> + + returnM (Match pats' maybe_rhs_sig' grhss', grhss_fvs `plusFV` ty_fvs) + -- The bindPatSigTyVars and rnPatsAndThen will remove the bound FVs + where + rhs_sig_tys = case maybe_rhs_sig of + Nothing -> [] + Just ty -> [ty] + doc_sig = text "In a result type-signature" \end{code} + %************************************************************************ %* * \subsubsection{Guarded right-hand sides (GRHSs)} @@ -219,31 +103,28 @@ rnMatch match@(Match _ pats maybe_rhs_sig grhss) %************************************************************************ \begin{code} -rnGRHSs :: RdrNameGRHSs -> RnMS (RenamedGRHSs, FreeVars) - -rnGRHSs (GRHSs grhss binds maybe_ty) - = ASSERT( not (maybeToBool maybe_ty) ) - rnBinds binds $ \ binds' -> - mapFvRn rnGRHS grhss `thenRn` \ (grhss', fvGRHSs) -> - returnRn (GRHSs grhss' binds' Nothing, fvGRHSs) - -rnGRHS (GRHS guarded locn) - = pushSrcLocRn locn $ - (if not (opt_GlasgowExts || is_standard_guard guarded) then - addWarnRn (nonStdGuardErr guarded) - else - returnRn () - ) `thenRn_` - - rnStmts rnExpr guarded `thenRn` \ (guarded', fvs) -> - returnRn (GRHS guarded' locn, fvs) +rnGRHSs :: HsMatchContext Name -> RdrNameGRHSs -> RnM (RenamedGRHSs, FreeVars) + +rnGRHSs ctxt (GRHSs grhss binds _) + = rnBindsAndThen binds $ \ binds' -> + mapFvRn (rnGRHS ctxt) grhss `thenM` \ (grhss', fvGRHSs) -> + returnM (GRHSs grhss' binds' placeHolderType, fvGRHSs) + +rnGRHS ctxt (GRHS guarded locn) + = addSrcLoc locn $ + doptM Opt_GlasgowExts `thenM` \ opt_GlasgowExts -> + checkM (opt_GlasgowExts || is_standard_guard guarded) + (addWarn (nonStdGuardErr guarded)) `thenM_` + + rnStmts (PatGuard ctxt) guarded `thenM` \ (guarded', fvs) -> + returnM (GRHS guarded' locn, fvs) where -- Standard Haskell 1.4 guards are just a single boolean -- expression, rather than a list of qualifiers as in the -- Glasgow extension - is_standard_guard [ExprStmt _ _] = True - is_standard_guard [GuardStmt _ _, ExprStmt _ _] = True - is_standard_guard other = False + is_standard_guard [ResultStmt _ _] = True + is_standard_guard [ExprStmt _ _ _, ResultStmt _ _] = True + is_standard_guard other = False \end{code} %************************************************************************ @@ -253,20 +134,20 @@ rnGRHS (GRHS guarded locn) %************************************************************************ \begin{code} -rnExprs :: [RdrNameHsExpr] -> RnMS ([RenamedHsExpr], FreeVars) +rnExprs :: [RdrNameHsExpr] -> RnM ([RenamedHsExpr], FreeVars) rnExprs ls = rnExprs' ls emptyUniqSet where - rnExprs' [] acc = returnRn ([], acc) + rnExprs' [] acc = returnM ([], acc) rnExprs' (expr:exprs) acc - = rnExpr expr `thenRn` \ (expr', fvExpr) -> + = rnExpr expr `thenM` \ (expr', fvExpr) -> -- Now we do a "seq" on the free vars because typically it's small -- or empty, especially in very long lists of constants let acc' = acc `plusFV` fvExpr in - (grubby_seqNameSet acc' rnExprs') exprs acc' `thenRn` \ (exprs', fvExprs) -> - returnRn (expr':exprs', fvExprs) + (grubby_seqNameSet acc' rnExprs') exprs acc' `thenM` \ (exprs', fvExprs) -> + returnM (expr':exprs', fvExprs) -- Grubby little function to do "seq" on namesets; replace by proper seq when GHC can do seq grubby_seqNameSet ns result | isNullUFM ns = result @@ -276,192 +157,217 @@ grubby_seqNameSet ns result | isNullUFM ns = result Variables. We look up the variable and return the resulting name. \begin{code} -rnExpr :: RdrNameHsExpr -> RnMS (RenamedHsExpr, FreeVars) +rnExpr :: RdrNameHsExpr -> RnM (RenamedHsExpr, FreeVars) rnExpr (HsVar v) - = lookupOccRn v `thenRn` \ name -> - if name `hasKey` assertIdKey then - -- We expand it to (GHCerr.assert__ location) - mkAssertExpr + = lookupOccRn v `thenM` \ name -> + if name `hasKey` assertIdKey && not opt_IgnoreAsserts then + -- We expand it to (GHC.Err.assertError location_string) + mkAssertErrorExpr else - -- The normal case - returnRn (HsVar name, unitFV name) + -- The normal case. Even if the Id was 'assert', if we are + -- ignoring assertions we leave it as GHC.Base.assert; + -- this function just ignores its first arg. + returnM (HsVar name, unitFV name) rnExpr (HsIPVar v) - = newIPName v `thenRn` \ name -> - returnRn (HsIPVar name, emptyFVs) - --- Special case for integral literals with a large magnitude: --- They are transformed into an expression involving only smaller --- integral literals. This improves constant folding. -rnExpr (HsLit (HsInt i)) - | not (inIntRange i) = rnExpr (horner tARGET_MAX_INT i) + = newIPName v `thenM` \ name -> + let + fvs = case name of + Linear _ -> mkFVs [splitName, fstName, sndName] + Dupable _ -> emptyFVs + in + returnM (HsIPVar name, fvs) rnExpr (HsLit lit) - = litOccurrence lit `thenRn` \ fvs -> - returnRn (HsLit lit, fvs) + = litFVs lit `thenM` \ fvs -> + returnM (HsLit lit, fvs) + +rnExpr (HsOverLit lit) + = rnOverLit lit `thenM` \ (lit', fvs) -> + returnM (HsOverLit lit', fvs) rnExpr (HsLam match) - = rnMatch match `thenRn` \ (match', fvMatch) -> - returnRn (HsLam match', fvMatch) + = rnMatch LambdaExpr match `thenM` \ (match', fvMatch) -> + returnM (HsLam match', fvMatch) rnExpr (HsApp fun arg) - = rnExpr fun `thenRn` \ (fun',fvFun) -> - rnExpr arg `thenRn` \ (arg',fvArg) -> - returnRn (HsApp fun' arg', fvFun `plusFV` fvArg) + = rnExpr fun `thenM` \ (fun',fvFun) -> + rnExpr arg `thenM` \ (arg',fvArg) -> + returnM (HsApp fun' arg', fvFun `plusFV` fvArg) rnExpr (OpApp e1 op _ e2) - = rnExpr e1 `thenRn` \ (e1', fv_e1) -> - rnExpr e2 `thenRn` \ (e2', fv_e2) -> - rnExpr op `thenRn` \ (op'@(HsVar op_name), fv_op) -> + = rnExpr e1 `thenM` \ (e1', fv_e1) -> + rnExpr e2 `thenM` \ (e2', fv_e2) -> + rnExpr op `thenM` \ (op'@(HsVar op_name), fv_op) -> -- Deal with fixity -- When renaming code synthesised from "deriving" declarations -- we're in Interface mode, and we should ignore fixity; assume -- that the deriving code generator got the association correct -- Don't even look up the fixity when in interface mode - getModeRn `thenRn` \ mode -> - (case mode of - SourceMode -> lookupFixityRn op_name `thenRn` \ fixity -> - mkOpAppRn e1' op' fixity e2' - InterfaceMode -> returnRn (OpApp e1' op' defaultFixity e2') - ) `thenRn` \ final_e -> - - returnRn (final_e, + getModeRn `thenM` \ mode -> + (if isInterfaceMode mode + then returnM (OpApp e1' op' defaultFixity e2') + else lookupFixityRn op_name `thenM` \ fixity -> + mkOpAppRn e1' op' fixity e2' + ) `thenM` \ final_e -> + + returnM (final_e, fv_e1 `plusFV` fv_op `plusFV` fv_e2) --- constant-fold some negate applications on unboxed literals. Since --- negate is a polymorphic function, we have to do these here. -rnExpr (NegApp (HsLit (HsIntPrim i)) _) = rnExpr (HsLit (HsIntPrim (-i))) -rnExpr (NegApp (HsLit (HsFloatPrim i)) _) = rnExpr (HsLit (HsFloatPrim (-i))) -rnExpr (NegApp (HsLit (HsDoublePrim i)) _) = rnExpr (HsLit (HsDoublePrim (-i))) - -rnExpr (NegApp e n) - = rnExpr e `thenRn` \ (e', fv_e) -> - lookupOrigName negate_RDR `thenRn` \ neg -> - mkNegAppRn e' (HsVar neg) `thenRn` \ final_e -> - returnRn (final_e, fv_e `addOneFV` neg) +rnExpr (NegApp e _) + = rnExpr e `thenM` \ (e', fv_e) -> + lookupSyntaxName negateName `thenM` \ (neg_name, fv_neg) -> + mkNegAppRn e' neg_name `thenM` \ final_e -> + returnM (final_e, fv_e `plusFV` fv_neg) rnExpr (HsPar e) - = rnExpr e `thenRn` \ (e', fvs_e) -> - returnRn (HsPar e', fvs_e) + = rnExpr e `thenM` \ (e', fvs_e) -> + returnM (HsPar e', fvs_e) + +-- Template Haskell extensions +#ifdef GHCI +rnExpr (HsBracket br_body loc) + = addSrcLoc loc $ + checkGHCI (thErr "bracket") `thenM_` + rnBracket br_body `thenM` \ (body', fvs_e) -> + returnM (HsBracket body' loc, fvs_e `addOneFV` qTyConName) + -- We use the Q tycon as a proxy to haul in all the smart + -- constructors; see the hack in RnIfaces + +rnExpr (HsSplice n e loc) + = addSrcLoc loc $ + checkGHCI (thErr "splice") `thenM_` + newLocalsRn [(n,loc)] `thenM` \ [n'] -> + rnExpr e `thenM` \ (e', fvs_e) -> + returnM (HsSplice n' e' loc, fvs_e `addOneFV` qTyConName) + -- The qTyCon brutally pulls in all the meta stuff + +rnExpr (HsReify (Reify flavour name)) + = checkGHCI (thErr "reify") `thenM_` + lookupGlobalOccRn name `thenM` \ name' -> + -- For now, we can only reify top-level things + returnM (HsReify (Reify flavour name'), mkFVs [name', qTyConName]) + -- The qTyCon brutally pulls in all the meta stuff +#endif rnExpr section@(SectionL expr op) - = rnExpr expr `thenRn` \ (expr', fvs_expr) -> - rnExpr op `thenRn` \ (op', fvs_op) -> - checkSectionPrec "left" section op' expr' `thenRn_` - returnRn (SectionL expr' op', fvs_op `plusFV` fvs_expr) + = rnExpr expr `thenM` \ (expr', fvs_expr) -> + rnExpr op `thenM` \ (op', fvs_op) -> + checkSectionPrec InfixL section op' expr' `thenM_` + returnM (SectionL expr' op', fvs_op `plusFV` fvs_expr) rnExpr section@(SectionR op expr) - = rnExpr op `thenRn` \ (op', fvs_op) -> - rnExpr expr `thenRn` \ (expr', fvs_expr) -> - checkSectionPrec "right" section op' expr' `thenRn_` - returnRn (SectionR op' expr', fvs_op `plusFV` fvs_expr) + = rnExpr op `thenM` \ (op', fvs_op) -> + rnExpr expr `thenM` \ (expr', fvs_expr) -> + checkSectionPrec InfixR section op' expr' `thenM_` + returnM (SectionR op' expr', fvs_op `plusFV` fvs_expr) -rnExpr (HsCCall fun args may_gc is_casm fake_result_ty) +rnExpr (HsCCall fun args may_gc is_casm _) -- Check out the comment on RnIfaces.getNonWiredDataDecl about ccalls - = lookupOrigNames [ccallableClass_RDR, - creturnableClass_RDR, - ioDataCon_RDR] `thenRn` \ implicit_fvs -> - rnExprs args `thenRn` \ (args', fvs_args) -> - returnRn (HsCCall fun args' may_gc is_casm fake_result_ty, - fvs_args `plusFV` implicit_fvs) + = rnExprs args `thenM` \ (args', fvs_args) -> + returnM (HsCCall fun args' may_gc is_casm placeHolderType, + fvs_args `plusFV` mkFVs [cCallableClassName, + cReturnableClassName, + ioDataConName]) rnExpr (HsSCC lbl expr) - = rnExpr expr `thenRn` \ (expr', fvs_expr) -> - returnRn (HsSCC lbl expr', fvs_expr) + = rnExpr expr `thenM` \ (expr', fvs_expr) -> + returnM (HsSCC lbl expr', fvs_expr) rnExpr (HsCase expr ms src_loc) - = pushSrcLocRn src_loc $ - rnExpr expr `thenRn` \ (new_expr, e_fvs) -> - mapFvRn rnMatch ms `thenRn` \ (new_ms, ms_fvs) -> - returnRn (HsCase new_expr new_ms src_loc, e_fvs `plusFV` ms_fvs) + = addSrcLoc src_loc $ + rnExpr expr `thenM` \ (new_expr, e_fvs) -> + mapFvRn (rnMatch CaseAlt) ms `thenM` \ (new_ms, ms_fvs) -> + returnM (HsCase new_expr new_ms src_loc, e_fvs `plusFV` ms_fvs) rnExpr (HsLet binds expr) - = rnBinds binds $ \ binds' -> - rnExpr expr `thenRn` \ (expr',fvExpr) -> - returnRn (HsLet binds' expr', fvExpr) - -rnExpr (HsWith expr binds) - = rnExpr expr `thenRn` \ (expr',fvExpr) -> - rnIPBinds binds `thenRn` \ (binds',fvBinds) -> - returnRn (HsWith expr' binds', fvExpr `plusFV` fvBinds) - -rnExpr e@(HsDo do_or_lc stmts src_loc) - = pushSrcLocRn src_loc $ - lookupOrigNames implicit_rdr_names `thenRn` \ implicit_fvs -> - rnStmts rnExpr stmts `thenRn` \ (stmts', fvs) -> - -- check the statement list ends in an expression - case last stmts' of { - ExprStmt _ _ -> returnRn () ; - ReturnStmt _ -> returnRn () ; -- for list comprehensions - _ -> addErrRn (doStmtListErr e) - } `thenRn_` - returnRn (HsDo do_or_lc stmts' src_loc, fvs `plusFV` implicit_fvs) - where - implicit_rdr_names = [foldr_RDR, build_RDR, monadClass_RDR] - -- Monad stuff should not be necessary for a list comprehension - -- but the typechecker looks up the bind and return Ids anyway - -- Oh well. + = rnBindsAndThen binds $ \ binds' -> + rnExpr expr `thenM` \ (expr',fvExpr) -> + returnM (HsLet binds' expr', fvExpr) + +rnExpr e@(HsDo do_or_lc stmts _ _ src_loc) + = addSrcLoc src_loc $ + rnStmts do_or_lc stmts `thenM` \ (stmts', fvs) -> + -- Check the statement list ends in an expression + case last stmts' of { + ResultStmt _ _ -> returnM () ; + _ -> addErr (doStmtListErr do_or_lc e) + } `thenM_` -rnExpr (ExplicitList exps) - = rnExprs exps `thenRn` \ (exps', fvs) -> - returnRn (ExplicitList exps', fvs `addOneFV` listTyCon_name) + -- Generate the rebindable syntax for the monad + mapAndUnzipM lookupSyntaxName + (syntax_names do_or_lc) `thenM` \ (monad_names', monad_fvs) -> -rnExpr (ExplicitTuple exps boxity) - = rnExprs exps `thenRn` \ (exps', fvs) -> - returnRn (ExplicitTuple exps' boxity, fvs `addOneFV` tycon_name) + returnM (HsDo do_or_lc stmts' monad_names' placeHolderType src_loc, + fvs `plusFV` implicit_fvs do_or_lc `plusFV` plusFVs monad_fvs) where - tycon_name = tupleTyCon_name boxity (length exps) + implicit_fvs PArrComp = mkFVs [replicatePName, mapPName, filterPName, crossPName, zipPName] + implicit_fvs ListComp = mkFVs [foldrName, buildName] + implicit_fvs DoExpr = emptyFVs + implicit_fvs MDoExpr = emptyFVs + + syntax_names DoExpr = monadNames + syntax_names MDoExpr = monadNames ++ [mfixName] + syntax_names other = [] + +rnExpr (ExplicitList _ exps) + = rnExprs exps `thenM` \ (exps', fvs) -> + returnM (ExplicitList placeHolderType exps', fvs `addOneFV` listTyCon_name) + +rnExpr (ExplicitPArr _ exps) + = rnExprs exps `thenM` \ (exps', fvs) -> + returnM (ExplicitPArr placeHolderType exps', + fvs `addOneFV` toPName `addOneFV` parrTyCon_name) + +rnExpr e@(ExplicitTuple exps boxity) + = checkTupSize tup_size `thenM_` + rnExprs exps `thenM` \ (exps', fvs) -> + returnM (ExplicitTuple exps' boxity, fvs `addOneFV` tycon_name) + where + tup_size = length exps + tycon_name = tupleTyCon_name boxity tup_size rnExpr (RecordCon con_id rbinds) - = lookupOccRn con_id `thenRn` \ conname -> - rnRbinds "construction" rbinds `thenRn` \ (rbinds', fvRbinds) -> - returnRn (RecordCon conname rbinds', fvRbinds `addOneFV` conname) + = lookupOccRn con_id `thenM` \ conname -> + rnRbinds "construction" rbinds `thenM` \ (rbinds', fvRbinds) -> + returnM (RecordCon conname rbinds', fvRbinds `addOneFV` conname) rnExpr (RecordUpd expr rbinds) - = rnExpr expr `thenRn` \ (expr', fvExpr) -> - rnRbinds "update" rbinds `thenRn` \ (rbinds', fvRbinds) -> - returnRn (RecordUpd expr' rbinds', fvExpr `plusFV` fvRbinds) + = rnExpr expr `thenM` \ (expr', fvExpr) -> + rnRbinds "update" rbinds `thenM` \ (rbinds', fvRbinds) -> + returnM (RecordUpd expr' rbinds', fvExpr `plusFV` fvRbinds) rnExpr (ExprWithTySig expr pty) - = rnExpr expr `thenRn` \ (expr', fvExpr) -> - rnHsSigType (text "an expression") pty `thenRn` \ (pty', fvTy) -> - returnRn (ExprWithTySig expr' pty', fvExpr `plusFV` fvTy) + = rnExpr expr `thenM` \ (expr', fvExpr) -> + rnHsTypeFVs doc pty `thenM` \ (pty', fvTy) -> + returnM (ExprWithTySig expr' pty', fvExpr `plusFV` fvTy) + where + doc = text "In an expression type signature" rnExpr (HsIf p b1 b2 src_loc) - = pushSrcLocRn src_loc $ - rnExpr p `thenRn` \ (p', fvP) -> - rnExpr b1 `thenRn` \ (b1', fvB1) -> - rnExpr b2 `thenRn` \ (b2', fvB2) -> - returnRn (HsIf p' b1' b2' src_loc, plusFVs [fvP, fvB1, fvB2]) + = addSrcLoc src_loc $ + rnExpr p `thenM` \ (p', fvP) -> + rnExpr b1 `thenM` \ (b1', fvB1) -> + rnExpr b2 `thenM` \ (b2', fvB2) -> + returnM (HsIf p' b1' b2' src_loc, plusFVs [fvP, fvB1, fvB2]) + +rnExpr (HsType a) + = rnHsTypeFVs doc a `thenM` \ (t, fvT) -> + returnM (HsType t, fvT) + where + doc = text "In a type argument" rnExpr (ArithSeqIn seq) - = lookupOrigName enumClass_RDR `thenRn` \ enum -> - rn_seq seq `thenRn` \ (new_seq, fvs) -> - returnRn (ArithSeqIn new_seq, fvs `addOneFV` enum) - where - rn_seq (From expr) - = rnExpr expr `thenRn` \ (expr', fvExpr) -> - returnRn (From expr', fvExpr) - - rn_seq (FromThen expr1 expr2) - = rnExpr expr1 `thenRn` \ (expr1', fvExpr1) -> - rnExpr expr2 `thenRn` \ (expr2', fvExpr2) -> - returnRn (FromThen expr1' expr2', fvExpr1 `plusFV` fvExpr2) - - rn_seq (FromTo expr1 expr2) - = rnExpr expr1 `thenRn` \ (expr1', fvExpr1) -> - rnExpr expr2 `thenRn` \ (expr2', fvExpr2) -> - returnRn (FromTo expr1' expr2', fvExpr1 `plusFV` fvExpr2) - - rn_seq (FromThenTo expr1 expr2 expr3) - = rnExpr expr1 `thenRn` \ (expr1', fvExpr1) -> - rnExpr expr2 `thenRn` \ (expr2', fvExpr2) -> - rnExpr expr3 `thenRn` \ (expr3', fvExpr3) -> - returnRn (FromThenTo expr1' expr2' expr3', - plusFVs [fvExpr1, fvExpr2, fvExpr3]) + = rnArithSeq seq `thenM` \ (new_seq, fvs) -> + returnM (ArithSeqIn new_seq, fvs `addOneFV` enumClassName) + +rnExpr (PArrSeqIn seq) + = rnArithSeq seq `thenM` \ (new_seq, fvs) -> + returnM (PArrSeqIn new_seq, + fvs `plusFV` mkFVs [enumFromToPName, enumFromThenToPName]) \end{code} These three are pattern syntax appearing in expressions. @@ -469,77 +375,93 @@ Since all the symbols are reservedops we can simply reject them. We return a (bogus) EWildPat in each case. \begin{code} -rnExpr e@EWildPat = addErrRn (patSynErr e) `thenRn_` - returnRn (EWildPat, emptyFVs) - -rnExpr e@(EAsPat _ _) = addErrRn (patSynErr e) `thenRn_` - returnRn (EWildPat, emptyFVs) - -rnExpr e@(ELazyPat _) = addErrRn (patSynErr e) `thenRn_` - returnRn (EWildPat, emptyFVs) - --- Transform i into (x1 + (x2 + (x3 + (...) * b) * b) * b) with abs xi <= b -horner :: Integer -> Integer -> RdrNameHsExpr -horner b i | abs q <= 1 = if r == 0 || r == i then mkInt i else mkInt r `plus` mkInt (i-r) - | r == 0 = horner b q `times` mkInt b - | otherwise = mkInt r `plus` (horner b q `times` mkInt b) - where (q,r) = i `quotRem` b - mkInt i = HsLit (HsInt i) - plus = mkOp "+" - times = mkOp "*" - mkOp op = \x y -> HsPar (OpApp x (HsVar (mkSrcUnqual varName (_PK_ op))) (panic "fixity") y) +rnExpr e@EWildPat = addErr (patSynErr e) `thenM_` + returnM (EWildPat, emptyFVs) + +rnExpr e@(EAsPat _ _) = addErr (patSynErr e) `thenM_` + returnM (EWildPat, emptyFVs) + +rnExpr e@(ELazyPat _) = addErr (patSynErr e) `thenM_` + returnM (EWildPat, emptyFVs) \end{code} %************************************************************************ %* * -\subsubsection{@Rbinds@s and @Rpats@s: in record expressions} + Arithmetic sequences %* * %************************************************************************ \begin{code} -rnRbinds str rbinds - = mapRn_ field_dup_err dup_fields `thenRn_` - mapFvRn rn_rbind rbinds `thenRn` \ (rbinds', fvRbind) -> - returnRn (rbinds', fvRbind) - where - (_, dup_fields) = removeDups compare [ f | (f,_,_) <- rbinds ] +rnArithSeq (From expr) + = rnExpr expr `thenM` \ (expr', fvExpr) -> + returnM (From expr', fvExpr) + +rnArithSeq (FromThen expr1 expr2) + = rnExpr expr1 `thenM` \ (expr1', fvExpr1) -> + rnExpr expr2 `thenM` \ (expr2', fvExpr2) -> + returnM (FromThen expr1' expr2', fvExpr1 `plusFV` fvExpr2) + +rnArithSeq (FromTo expr1 expr2) + = rnExpr expr1 `thenM` \ (expr1', fvExpr1) -> + rnExpr expr2 `thenM` \ (expr2', fvExpr2) -> + returnM (FromTo expr1' expr2', fvExpr1 `plusFV` fvExpr2) + +rnArithSeq (FromThenTo expr1 expr2 expr3) + = rnExpr expr1 `thenM` \ (expr1', fvExpr1) -> + rnExpr expr2 `thenM` \ (expr2', fvExpr2) -> + rnExpr expr3 `thenM` \ (expr3', fvExpr3) -> + returnM (FromThenTo expr1' expr2' expr3', + plusFVs [fvExpr1, fvExpr2, fvExpr3]) +\end{code} - field_dup_err dups = addErrRn (dupFieldErr str dups) - rn_rbind (field, expr, pun) - = lookupGlobalOccRn field `thenRn` \ fieldname -> - rnExpr expr `thenRn` \ (expr', fvExpr) -> - returnRn ((fieldname, expr', pun), fvExpr `addOneFV` fieldname) +%************************************************************************ +%* * +\subsubsection{@Rbinds@s and @Rpats@s: in record expressions} +%* * +%************************************************************************ -rnRpats rpats - = mapRn_ field_dup_err dup_fields `thenRn_` - mapFvRn rn_rpat rpats `thenRn` \ (rpats', fvs) -> - returnRn (rpats', fvs) +\begin{code} +rnRbinds str rbinds + = mappM_ field_dup_err dup_fields `thenM_` + mapFvRn rn_rbind rbinds `thenM` \ (rbinds', fvRbind) -> + returnM (rbinds', fvRbind) where - (_, dup_fields) = removeDups compare [ f | (f,_,_) <- rpats ] + (_, dup_fields) = removeDups compare [ f | (f,_) <- rbinds ] - field_dup_err dups = addErrRn (dupFieldErr "pattern" dups) + field_dup_err dups = addErr (dupFieldErr str dups) - rn_rpat (field, pat, pun) - = lookupGlobalOccRn field `thenRn` \ fieldname -> - rnPat pat `thenRn` \ (pat', fvs) -> - returnRn ((fieldname, pat', pun), fvs `addOneFV` fieldname) + rn_rbind (field, expr) + = lookupGlobalOccRn field `thenM` \ fieldname -> + rnExpr expr `thenM` \ (expr', fvExpr) -> + returnM ((fieldname, expr'), fvExpr `addOneFV` fieldname) \end{code} %************************************************************************ %* * -\subsubsection{@rnIPBinds@s: in implicit parameter bindings} * + Template Haskell brackets %* * %************************************************************************ \begin{code} -rnIPBinds [] = returnRn ([], emptyFVs) -rnIPBinds ((n, expr) : binds) - = newIPName n `thenRn` \ name -> - rnExpr expr `thenRn` \ (expr',fvExpr) -> - rnIPBinds binds `thenRn` \ (binds',fvBinds) -> - returnRn ((name, expr') : binds', fvExpr `plusFV` fvBinds) - +rnBracket (ExpBr e) = rnExpr e `thenM` \ (e', fvs) -> + returnM (ExpBr e', fvs) +rnBracket (PatBr p) = rnPat p `thenM` \ (p', fvs) -> + returnM (PatBr p', fvs) +rnBracket (TypBr t) = rnHsTypeFVs doc t `thenM` \ (t', fvs) -> + returnM (TypBr t', fvs) + where + doc = ptext SLIT("In a Template-Haskell quoted type") +rnBracket (DecBr group) + = importsFromLocalDecls group `thenM` \ (rdr_env, avails) -> + -- Discard avails (not useful here) + + updGblEnv (\gbl -> gbl { tcg_rdr_env = rdr_env `plusGlobalRdrEnv` tcg_rdr_env gbl }) $ + + rnSrcDecls group `thenM` \ (tcg_env, group', fvs) -> + -- Discard the tcg_env; it contains only extra info about fixity + + returnM (DecBr group', fvs) \end{code} %************************************************************************ @@ -548,65 +470,262 @@ rnIPBinds ((n, expr) : binds) %* * %************************************************************************ -Note that although some bound vars may appear in the free var set for -the first qual, these will eventually be removed by the caller. For -example, if we have @[p | r <- s, q <- r, p <- q]@, when doing -@[q <- r, p <- q]@, the free var set for @q <- r@ will -be @{r}@, and the free var set for the entire Quals will be @{r}@. This -@r@ will be removed only when we finally return from examining all the -Quals. +\begin{code} +rnStmts :: HsStmtContext Name -> [RdrNameStmt] -> RnM ([RenamedStmt], FreeVars) + +rnStmts MDoExpr stmts = rnMDoStmts stmts +rnStmts ctxt stmts = rnNormalStmts ctxt stmts + +rnNormalStmts :: HsStmtContext Name -> [RdrNameStmt] -> RnM ([RenamedStmt], FreeVars) +-- Used for cases *other* than recursive mdo +-- Implements nested scopes + +rnNormalStmts ctxt [] = returnM ([], emptyFVs) + -- Happens at the end of the sub-lists of a ParStmts + +rnNormalStmts ctxt (ExprStmt expr _ src_loc : stmts) + = addSrcLoc src_loc $ + rnExpr expr `thenM` \ (expr', fv_expr) -> + rnNormalStmts ctxt stmts `thenM` \ (stmts', fvs) -> + returnM (ExprStmt expr' placeHolderType src_loc : stmts', + fv_expr `plusFV` fvs) + +rnNormalStmts ctxt [ResultStmt expr src_loc] + = addSrcLoc src_loc $ + rnExpr expr `thenM` \ (expr', fv_expr) -> + returnM ([ResultStmt expr' src_loc], fv_expr) + +rnNormalStmts ctxt (BindStmt pat expr src_loc : stmts) + = addSrcLoc src_loc $ + rnExpr expr `thenM` \ (expr', fv_expr) -> + -- The binders do not scope over the expression + + rnPatsAndThen (StmtCtxt ctxt) [pat] $ \ [pat'] -> + rnNormalStmts ctxt stmts `thenM` \ (stmts', fvs) -> + returnM (BindStmt pat' expr' src_loc : stmts', + fv_expr `plusFV` fvs) -- fv_expr shouldn't really be filtered by + -- the rnPatsAndThen, but it does not matter + +rnNormalStmts ctxt (LetStmt binds : stmts) + = checkErr (ok ctxt binds) (badIpBinds binds) `thenM_` + rnBindsAndThen binds ( \ binds' -> + rnNormalStmts ctxt stmts `thenM` \ (stmts', fvs) -> + returnM (LetStmt binds' : stmts', fvs)) + where + -- We do not allow implicit-parameter bindings in a parallel + -- list comprehension. I'm not sure what it might mean. + ok (ParStmtCtxt _) (IPBinds _ _) = False + ok _ _ = True + +rnNormalStmts ctxt (ParStmt stmtss : stmts) + = mapFvRn (rnNormalStmts (ParStmtCtxt ctxt)) stmtss `thenM` \ (stmtss', fv_stmtss) -> + let + bndrss = map collectStmtsBinders stmtss' + in + foldlM checkBndrs [] bndrss `thenM` \ new_binders -> + bindLocalNamesFV new_binders $ + -- Note: binders are returned in scope order, so one may + -- shadow the next; e.g. x <- xs; x <- ys + rnNormalStmts ctxt stmts `thenM` \ (stmts', fvs) -> + returnM (ParStmtOut (bndrss `zip` stmtss') : stmts', + fv_stmtss `plusFV` fvs) + + where + checkBndrs all_bndrs bndrs + = checkErr (null common) (err (head common)) `thenM_` + returnM (bndrs ++ all_bndrs) + where + common = intersectBy eqOcc all_bndrs bndrs + + eqOcc n1 n2 = nameOccName n1 == nameOccName n2 + err v = ptext SLIT("Duplicate binding in parallel list comprehension for:") + <+> quotes (ppr v) + +rnNormalStmts ctxt stmts = pprPanic "rnNormalStmts" (ppr stmts) +\end{code} + + +%************************************************************************ +%* * +\subsubsection{Precedence Parsing} +%* * +%************************************************************************ \begin{code} -type RnExprTy = RdrNameHsExpr -> RnMS (RenamedHsExpr, FreeVars) - -rnStmts :: RnExprTy - -> [RdrNameStmt] - -> RnMS ([RenamedStmt], FreeVars) - -rnStmts rn_expr [] - = returnRn ([], emptyFVs) - -rnStmts rn_expr (stmt:stmts) - = rnStmt rn_expr stmt $ \ stmt' -> - rnStmts rn_expr stmts `thenRn` \ (stmts', fvs) -> - returnRn (stmt' : stmts', fvs) - -rnStmt :: RnExprTy -> RdrNameStmt - -> (RenamedStmt -> RnMS (a, FreeVars)) - -> RnMS (a, FreeVars) --- Because of mutual recursion we have to pass in rnExpr. - -rnStmt rn_expr (BindStmt pat expr src_loc) thing_inside - = pushSrcLocRn src_loc $ - rn_expr expr `thenRn` \ (expr', fv_expr) -> - bindLocalsFVRn doc binders $ \ new_binders -> - rnPat pat `thenRn` \ (pat', fv_pat) -> - thing_inside (BindStmt pat' expr' src_loc) `thenRn` \ (result, fvs) -> - returnRn (result, fv_expr `plusFV` fvs `plusFV` fv_pat) +type Defs = NameSet +type Uses = NameSet -- Same as FreeVars really +type FwdRefs = NameSet +type Segment = (Defs, + Uses, -- May include defs + FwdRefs, -- A subset of uses that are + -- (a) used before they are bound in this segment, or + -- (b) used here, and bound in subsequent segments + [RenamedStmt]) + +---------------------------------------------------- +rnMDoStmts :: [RdrNameStmt] -> RnM ([RenamedStmt], FreeVars) +rnMDoStmts stmts + = -- Step1: bring all the binders of the mdo into scope + bindLocalsRn doc (collectStmtsBinders stmts) $ \ _ -> + + -- Step 2: Rename each individual stmt, making a + -- singleton segment. At this stage the FwdRefs field + -- isn't finished: it's empty for all except a BindStmt + -- for which it's the fwd refs within the bind itself + mappM rn_mdo_stmt stmts `thenM` \ segs -> + let + -- Step 3: Fill in the fwd refs. + -- The segments are all singletons, but their fwd-ref + -- field mentions all the things used by the segment + -- that are bound after their use + segs_w_fwd_refs = addFwdRefs segs + + -- Step 4: Group together the segments to make bigger segments + -- Invariant: in the result, no segment uses a variable + -- bound in a later segment + grouped_segs = glomSegments segs_w_fwd_refs + + -- Step 5: Turn the segments into Stmts + -- Use RecStmt when and only when there are fwd refs + -- Also gather up the uses from the end towards the + -- start, so we can tell the RecStmt which things are + -- used 'after' the RecStmt + stmts_w_fvs = segsToStmts grouped_segs + in + returnM stmts_w_fvs where - binders = collectPatBinders pat - doc = text "a pattern in do binding" - -rnStmt rn_expr (ExprStmt expr src_loc) thing_inside - = pushSrcLocRn src_loc $ - rn_expr expr `thenRn` \ (expr', fv_expr) -> - thing_inside (ExprStmt expr' src_loc) `thenRn` \ (result, fvs) -> - returnRn (result, fv_expr `plusFV` fvs) - -rnStmt rn_expr (GuardStmt expr src_loc) thing_inside - = pushSrcLocRn src_loc $ - rn_expr expr `thenRn` \ (expr', fv_expr) -> - thing_inside (GuardStmt expr' src_loc) `thenRn` \ (result, fvs) -> - returnRn (result, fv_expr `plusFV` fvs) - -rnStmt rn_expr (ReturnStmt expr) thing_inside - = rn_expr expr `thenRn` \ (expr', fv_expr) -> - thing_inside (ReturnStmt expr') `thenRn` \ (result, fvs) -> - returnRn (result, fv_expr `plusFV` fvs) - -rnStmt rn_expr (LetStmt binds) thing_inside - = rnBinds binds $ \ binds' -> - thing_inside (LetStmt binds') + doc = text "In a mdo-expression" + +---------------------------------------------------- +rn_mdo_stmt :: RdrNameStmt -> RnM Segment + -- Assumes all binders are already in scope + -- Turns each stmt into a singleton Stmt + +rn_mdo_stmt (ExprStmt expr _ src_loc) + = addSrcLoc src_loc (rnExpr expr) `thenM` \ (expr', fvs) -> + returnM (emptyNameSet, fvs, emptyNameSet, + [ExprStmt expr' placeHolderType src_loc]) + +rn_mdo_stmt (ResultStmt expr src_loc) + = addSrcLoc src_loc (rnExpr expr) `thenM` \ (expr', fvs) -> + returnM (emptyNameSet, fvs, emptyNameSet, + [ResultStmt expr' src_loc]) + +rn_mdo_stmt (BindStmt pat expr src_loc) + = addSrcLoc src_loc $ + rnExpr expr `thenM` \ (expr', fv_expr) -> + rnPat pat `thenM` \ (pat', fv_pat) -> + let + bndrs = mkNameSet (collectPatBinders pat') + fvs = fv_expr `plusFV` fv_pat + in + returnM (bndrs, fvs, bndrs `intersectNameSet` fvs, + [BindStmt pat' expr' src_loc]) + +rn_mdo_stmt (LetStmt binds) + = rnBinds binds `thenM` \ (binds', fv_binds) -> + returnM (mkNameSet (collectHsBinders binds'), + fv_binds, emptyNameSet, [LetStmt binds']) + +rn_mdo_stmt stmt@(ParStmt _) -- Syntactically illegal in mdo + = pprPanic "rn_mdo_stmt" (ppr stmt) + + +addFwdRefs :: [Segment] -> [Segment] +-- So far the segments only have forward refs *within* the Stmt +-- (which happens for bind: x <- ...x...) +-- This function adds the cross-seg fwd ref info + +addFwdRefs pairs + = fst (foldr mk_seg ([], emptyNameSet) pairs) + where + mk_seg (defs, uses, fwds, stmts) (segs, seg_defs) + = (new_seg : segs, all_defs) + where + new_seg = (defs, uses, new_fwds, stmts) + all_defs = seg_defs `unionNameSets` defs + new_fwds = fwds `unionNameSets` (uses `intersectNameSet` seg_defs) + -- Add the downstream fwd refs here + +---------------------------------------------------- +-- Glomming the singleton segments of an mdo into +-- minimal recursive groups. +-- +-- At first I thought this was just strongly connected components, but +-- there's an important constraint: the order of the stmts must not change. +-- +-- Consider +-- mdo { x <- ...y... +-- p <- z +-- y <- ...x... +-- q <- x +-- z <- y +-- r <- x } +-- +-- Here, the first stmt mention 'y', which is bound in the third. +-- But that means that the innocent second stmt (p <- z) gets caught +-- up in the recursion. And that in turn means that the binding for +-- 'z' has to be included... and so on. +-- +-- Start at the tail { r <- x } +-- Now add the next one { z <- y ; r <- x } +-- Now add one more { q <- x ; z <- y ; r <- x } +-- Now one more... but this time we have to group a bunch into rec +-- { rec { y <- ...x... ; q <- x ; z <- y } ; r <- x } +-- Now one more, which we can add on without a rec +-- { p <- z ; +-- rec { y <- ...x... ; q <- x ; z <- y } ; +-- r <- x } +-- Finally we add the last one; since it mentions y we have to +-- glom it togeher with the first two groups +-- { rec { x <- ...y...; p <- z ; y <- ...x... ; +-- q <- x ; z <- y } ; +-- r <- x } + +glomSegments :: [Segment] -> [Segment] + +glomSegments [seg] = [seg] +glomSegments ((defs,uses,fwds,stmts) : segs) + -- Actually stmts will always be a singleton + = (seg_defs, seg_uses, seg_fwds, seg_stmts) : others + where + segs' = glomSegments segs + (extras, others) = grab uses segs' + (ds, us, fs, ss) = unzip4 extras + + seg_defs = plusFVs ds `plusFV` defs + seg_uses = plusFVs us `plusFV` uses + seg_fwds = plusFVs fs `plusFV` fwds + seg_stmts = stmts ++ concat ss + + grab :: NameSet -- The client + -> [Segment] + -> ([Segment], -- Needed by the 'client' + [Segment]) -- Not needed by the client + -- The result is simply a split of the input + grab uses dus + = (reverse yeses, reverse noes) + where + (noes, yeses) = span not_needed (reverse dus) + not_needed (defs,_,_,_) = not (intersectsNameSet defs uses) + + +---------------------------------------------------- +segsToStmts :: [Segment] -> ([RenamedStmt], FreeVars) + +segsToStmts [] = ([], emptyFVs) +segsToStmts ((defs, uses, fwds, ss) : segs) + = (new_stmt : later_stmts, later_uses `plusFV` uses) + where + (later_stmts, later_uses) = segsToStmts segs + new_stmt | non_rec = head ss + | otherwise = RecStmt rec_names ss [] + where + non_rec = isSingleton ss && isEmptyNameSet fwds + rec_names = nameSetToList (fwds `plusFV` (defs `intersectNameSet` later_uses)) + -- The names for the fixpoint are + -- (a) the ones needed after the RecStmt + -- (b) the forward refs within the fixpoint \end{code} %************************************************************************ @@ -630,40 +749,40 @@ mkOpAppRn :: RenamedHsExpr -- Left operand; already rearranged -> RenamedHsExpr -> Fixity -- Operator and fixity -> RenamedHsExpr -- Right operand (not an OpApp, but might -- be a NegApp) - -> RnMS RenamedHsExpr + -> RnM RenamedHsExpr --------------------------- -- (e11 `op1` e12) `op2` e2 mkOpAppRn e1@(OpApp e11 op1 fix1 e12) op2 fix2 e2 | nofix_error - = addErrRn (precParseErr (ppr_op op1,fix1) (ppr_op op2,fix2)) `thenRn_` - returnRn (OpApp e1 op2 fix2 e2) + = addErr (precParseErr (ppr_op op1,fix1) (ppr_op op2,fix2)) `thenM_` + returnM (OpApp e1 op2 fix2 e2) | associate_right - = mkOpAppRn e12 op2 fix2 e2 `thenRn` \ new_e -> - returnRn (OpApp e11 op1 fix1 new_e) + = mkOpAppRn e12 op2 fix2 e2 `thenM` \ new_e -> + returnM (OpApp e11 op1 fix1 new_e) where (nofix_error, associate_right) = compareFixity fix1 fix2 --------------------------- -- (- neg_arg) `op` e2 -mkOpAppRn e1@(NegApp neg_arg neg_op) op2 fix2 e2 +mkOpAppRn e1@(NegApp neg_arg neg_name) op2 fix2 e2 | nofix_error - = addErrRn (precParseErr (pp_prefix_minus,negateFixity) (ppr_op op2,fix2)) `thenRn_` - returnRn (OpApp e1 op2 fix2 e2) + = addErr (precParseErr (pp_prefix_minus,negateFixity) (ppr_op op2,fix2)) `thenM_` + returnM (OpApp e1 op2 fix2 e2) | associate_right - = mkOpAppRn neg_arg op2 fix2 e2 `thenRn` \ new_e -> - returnRn (NegApp new_e neg_op) + = mkOpAppRn neg_arg op2 fix2 e2 `thenM` \ new_e -> + returnM (NegApp new_e neg_name) where (nofix_error, associate_right) = compareFixity negateFixity fix2 --------------------------- -- e1 `op` - neg_arg -mkOpAppRn e1 op1 fix1 e2@(NegApp neg_arg neg_op) -- NegApp can occur on the right - | not associate_right -- We *want* right association - = addErrRn (precParseErr (ppr_op op1, fix1) (pp_prefix_minus, negateFixity)) `thenRn_` - returnRn (OpApp e1 op1 fix1 e2) +mkOpAppRn e1 op1 fix1 e2@(NegApp neg_arg _) -- NegApp can occur on the right + | not associate_right -- We *want* right association + = addErr (precParseErr (ppr_op op1, fix1) (pp_prefix_minus, negateFixity)) `thenM_` + returnM (OpApp e1 op1 fix1 e2) where (_, associate_right) = compareFixity fix1 negateFixity @@ -673,7 +792,7 @@ mkOpAppRn e1 op fix e2 -- Default case, no rearrangment = ASSERT2( right_op_ok fix e2, ppr e1 $$ text "---" $$ ppr op $$ text "---" $$ ppr fix $$ text "---" $$ ppr e2 ) - returnRn (OpApp e1 op fix e2) + returnM (OpApp e1 op fix e2) -- Parser left-associates everything, but -- derived instances may have correctly-associated things to @@ -686,71 +805,38 @@ right_op_ok fix1 other = True -- Parser initially makes negation bind more tightly than any other operator -mkNegAppRn neg_arg neg_op +mkNegAppRn neg_arg neg_name = #ifdef DEBUG - getModeRn `thenRn` \ mode -> + getModeRn `thenM` \ mode -> ASSERT( not_op_app mode neg_arg ) #endif - returnRn (NegApp neg_arg neg_op) + returnM (NegApp neg_arg neg_name) not_op_app SourceMode (OpApp _ _ _ _) = False not_op_app mode other = True \end{code} \begin{code} -mkConOpPatRn :: RenamedPat -> Name -> Fixity -> RenamedPat - -> RnMS RenamedPat - -mkConOpPatRn p1@(ConOpPatIn p11 op1 fix1 p12) - op2 fix2 p2 - | nofix_error - = addErrRn (precParseErr (ppr_op op1,fix1) (ppr_op op2,fix2)) `thenRn_` - returnRn (ConOpPatIn p1 op2 fix2 p2) - - | associate_right - = mkConOpPatRn p12 op2 fix2 p2 `thenRn` \ new_p -> - returnRn (ConOpPatIn p11 op1 fix1 new_p) - - where - (nofix_error, associate_right) = compareFixity fix1 fix2 - -mkConOpPatRn p1@(NegPatIn neg_arg) - op2 - fix2@(Fixity prec2 dir2) - p2 - | prec2 > negatePrecedence -- Precedence of unary - is wired in - = addErrRn (precParseNegPatErr (ppr_op op2,fix2)) `thenRn_` - returnRn (ConOpPatIn p1 op2 fix2 p2) - -mkConOpPatRn p1 op fix p2 -- Default case, no rearrangment - = ASSERT( not_op_pat p2 ) - returnRn (ConOpPatIn p1 op fix p2) - -not_op_pat (ConOpPatIn _ _ _ _) = False -not_op_pat other = True -\end{code} - -\begin{code} -checkPrecMatch :: Bool -> Name -> RenamedMatch -> RnMS () +checkPrecMatch :: Bool -> Name -> RenamedMatch -> RnM () checkPrecMatch False fn match - = returnRn () + = returnM () -checkPrecMatch True op (Match _ (p1:p2:_) _ _) +checkPrecMatch True op (Match (p1:p2:_) _ _) -- True indicates an infix lhs - = getModeRn `thenRn` \ mode -> + = getModeRn `thenM` \ mode -> -- See comments with rnExpr (OpApp ...) - case mode of - InterfaceMode -> returnRn () - SourceMode -> checkPrec op p1 False `thenRn_` - checkPrec op p2 True + if isInterfaceMode mode + then returnM () + else checkPrec op p1 False `thenM_` + checkPrec op p2 True checkPrecMatch True op _ = panic "checkPrecMatch" -checkPrec op (ConOpPatIn _ op1 _ _) right - = lookupFixityRn op `thenRn` \ op_fix@(Fixity op_prec op_dir) -> - lookupFixityRn op1 `thenRn` \ op1_fix@(Fixity op1_prec op1_dir) -> +checkPrec op (ConPatIn op1 (InfixCon _ _)) right + = lookupFixityRn op `thenM` \ op_fix@(Fixity op_prec op_dir) -> + lookupFixityRn op1 `thenM` \ op1_fix@(Fixity op1_prec op1_dir) -> let inf_ok = op1_prec > op_prec || (op1_prec == op_prec && @@ -761,104 +847,30 @@ checkPrec op (ConOpPatIn _ op1 _ _) right info1 = (ppr_op op1, op1_fix) (infol, infor) = if right then (info, info1) else (info1, info) in - checkRn inf_ok (precParseErr infol infor) - -checkPrec op (NegPatIn _) right - = lookupFixityRn op `thenRn` \ op_fix@(Fixity op_prec op_dir) -> - checkRn (op_prec <= negatePrecedence) (precParseNegPatErr (ppr_op op,op_fix)) + checkErr inf_ok (precParseErr infol infor) checkPrec op pat right - = returnRn () + = returnM () -- Check precedence of (arg op) or (op arg) respectively --- If arg is itself an operator application, its precedence should --- be higher than that of op -checkSectionPrec left_or_right section op arg +-- If arg is itself an operator application, then either +-- (a) its precedence must be higher than that of op +-- (b) its precedency & associativity must be the same as that of op +checkSectionPrec direction section op arg = case arg of OpApp _ op fix _ -> go_for_it (ppr_op op) fix - NegApp _ op -> go_for_it pp_prefix_minus negateFixity - other -> returnRn () + NegApp _ _ -> go_for_it pp_prefix_minus negateFixity + other -> returnM () where HsVar op_name = op - go_for_it pp_arg_op arg_fix@(Fixity arg_prec _) - = lookupFixityRn op_name `thenRn` \ op_fix@(Fixity op_prec _) -> - checkRn (op_prec < arg_prec) - (sectionPrecErr (ppr_op op_name, op_fix) (pp_arg_op, arg_fix) section) + go_for_it pp_arg_op arg_fix@(Fixity arg_prec assoc) + = lookupFixityRn op_name `thenM` \ op_fix@(Fixity op_prec _) -> + checkErr (op_prec < arg_prec + || op_prec == arg_prec && direction == assoc) + (sectionPrecErr (ppr_op op_name, op_fix) + (pp_arg_op, arg_fix) section) \end{code} -Consider -\begin{verbatim} - a `op1` b `op2` c -\end{verbatim} -@(compareFixity op1 op2)@ tells which way to arrange appication, or -whether there's an error. - -\begin{code} -compareFixity :: Fixity -> Fixity - -> (Bool, -- Error please - Bool) -- Associate to the right: a op1 (b op2 c) -compareFixity (Fixity prec1 dir1) (Fixity prec2 dir2) - = case prec1 `compare` prec2 of - GT -> left - LT -> right - EQ -> case (dir1, dir2) of - (InfixR, InfixR) -> right - (InfixL, InfixL) -> left - _ -> error_please - where - right = (False, True) - left = (False, False) - error_please = (True, False) -\end{code} - -%************************************************************************ -%* * -\subsubsection{Literals} -%* * -%************************************************************************ - -When literals occur we have to make sure -that the types and classes they involve -are made available. - -\begin{code} -litOccurrence (HsChar _) - = returnRn (unitFV charTyCon_name) - -litOccurrence (HsCharPrim _) - = returnRn (unitFV (getName charPrimTyCon)) - -litOccurrence (HsString _) - = returnRn (unitFV listTyCon_name `plusFV` unitFV charTyCon_name) - -litOccurrence (HsStringPrim _) - = returnRn (unitFV (getName addrPrimTyCon)) - -litOccurrence (HsInt _) - = lookupOrigNames [numClass_RDR, addr2Integer_RDR] - -- Int and Integer are forced in by Num - -litOccurrence (HsFrac _) - = lookupOrigNames [fractionalClass_RDR,ratioDataCon_RDR,addr2Integer_RDR] - -- We have to make sure that the Ratio type is imported with - -- its constructor, because literals of type Ratio t are - -- built with that constructor. - -- The Rational type is needed too, but that will come in - -- when fractionalClass does. - -litOccurrence (HsIntPrim _) - = returnRn (unitFV (getName intPrimTyCon)) - -litOccurrence (HsFloatPrim _) - = returnRn (unitFV (getName floatPrimTyCon)) - -litOccurrence (HsDoublePrim _) - = returnRn (unitFV (getName doublePrimTyCon)) - -litOccurrence (HsLitLit _) - = lookupOrigName ccallableClass_RDR `thenRn` \ cc -> - returnRn (unitFV cc) -\end{code} %************************************************************************ %* * @@ -867,34 +879,15 @@ litOccurrence (HsLitLit _) %************************************************************************ \begin{code} -mkAssertExpr :: RnMS (RenamedHsExpr, FreeVars) -mkAssertExpr = - lookupOrigName assertErr_RDR `thenRn` \ name -> - getSrcLocRn `thenRn` \ sloc -> - - -- if we're ignoring asserts, return (\ _ e -> e) - -- if not, return (assertError "src-loc") - - if opt_IgnoreAsserts then - getUniqRn `thenRn` \ uniq -> - let - vname = mkSysLocalName uniq SLIT("v") - expr = HsLam ignorePredMatch - loc = nameSrcLoc vname - ignorePredMatch = Match [] [WildPatIn, VarPatIn vname] Nothing - (GRHSs [GRHS [ExprStmt (HsVar vname) loc] loc] - EmptyBinds Nothing) - in - returnRn (expr, unitFV name) - else +mkAssertErrorExpr :: RnM (RenamedHsExpr, FreeVars) +-- Return an expression for (assertError "Foo.hs:27") +mkAssertErrorExpr + = getSrcLocM `thenM` \ sloc -> let - expr = - HsApp (HsVar name) - (HsLit (HsString (_PK_ (showSDoc (ppr sloc))))) - + expr = HsApp (HsVar assertErrorName) (HsLit msg) + msg = HsStringPrim (mkFastString (stringToUtf8 (showSDoc (ppr sloc)))) in - returnRn (expr, unitFV name) - + returnM (expr, unitFV assertErrorName) \end{code} %************************************************************************ @@ -905,49 +898,30 @@ mkAssertExpr = \begin{code} ppr_op op = quotes (ppr op) -- Here, op can be a Name or a (Var n), where n is a Name -ppr_opfix (pp_op, fixity) = pp_op <+> brackets (ppr fixity) pp_prefix_minus = ptext SLIT("prefix `-'") -dupFieldErr str (dup:rest) - = hsep [ptext SLIT("duplicate field name"), - quotes (ppr dup), - ptext SLIT("in record"), text str] - -negPatErr pat - = sep [pp_prefix_minus <+> ptext SLIT("not applied to literal in pattern"), - quotes (ppr pat)] - -precParseNegPatErr op - = hang (ptext SLIT("precedence parsing error")) - 4 (hsep [pp_prefix_minus <+> ptext SLIT("has lower precedence than"), - ppr_opfix op, - ptext SLIT("in pattern")]) - -precParseErr op1 op2 - = hang (ptext SLIT("precedence parsing error")) - 4 (hsep [ptext SLIT("cannot mix"), ppr_opfix op1, ptext SLIT("and"), - ppr_opfix op2, - ptext SLIT("in the same infix expression")]) - -sectionPrecErr op arg_op section - = vcat [ptext SLIT("The operator") <+> ppr_opfix op <+> ptext SLIT("of a section"), - nest 4 (ptext SLIT("must have lower precedence than the operand") <+> ppr_opfix arg_op), - nest 4 (ptext SLIT("In the section:") <+> quotes (ppr section))] - nonStdGuardErr guard = hang (ptext SLIT("accepting non-standard pattern guards (-fglasgow-exts to suppress this message)") ) 4 (ppr guard) -patSigErr ty - = (ptext SLIT("Illegal signature in pattern:") <+> ppr ty) - $$ nest 4 (ptext SLIT("Use -fglasgow-exts to permit it")) - patSynErr e = sep [ptext SLIT("Pattern syntax in expression context:"), nest 4 (ppr e)] -doStmtListErr e - = sep [ptext SLIT("`do' statements must end in expression:"), +doStmtListErr do_or_lc e + = sep [quotes (text binder_name) <+> ptext SLIT("statements must end in expression:"), nest 4 (ppr e)] + where + binder_name = case do_or_lc of + MDoExpr -> "mdo" + other -> "do" + +thErr what + = ptext SLIT("Template Haskell") <+> text what <+> + ptext SLIT("illegal in a stage-1 compiler") + +badIpBinds binds + = hang (ptext SLIT("Implicit-parameter bindings illegal in a parallel list comprehension:")) 4 + (ppr binds) \end{code}