X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnExpr.lhs;h=a128c3561f4adce8928604f746a442eb90ec5cf7;hb=5d3051c66796dcf884b052f9e4afc3ed19b9f514;hp=b1481e30f5350862ba40e5d32b19421a7e2bc4e5;hpb=b44c6881743abf8f4c3c0612c482ede8b835ac37;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnExpr.lhs b/ghc/compiler/rename/RnExpr.lhs index b1481e3..a128c35 100644 --- a/ghc/compiler/rename/RnExpr.lhs +++ b/ghc/compiler/rename/RnExpr.lhs @@ -11,135 +11,59 @@ free variables. \begin{code} module RnExpr ( - rnMatch, rnGRHSs, rnExpr, rnExprs, rnStmts, - checkPrecMatch + rnLExpr, rnExpr, rnStmts ) where #include "HsVersions.h" -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 RnSource ( rnSrcDecls, rnSplice, checkTH ) +import RnBinds ( rnLocalBindsAndThen, rnValBinds, + rnMatchGroup, trimWith ) import HsSyn -import RdrHsSyn import RnHsSyn import TcRnMonad import RnEnv -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 OccName ( plusOccEnv ) +import RnNames ( getLocalDeclBinders, extendRdrEnvRn ) +import RnTypes ( rnHsTypeFVs, rnLPat, rnOverLit, rnPatsAndThen, rnLit, + mkOpFormRn, mkOpAppRn, mkNegAppRn, checkSectionPrec, + dupFieldErr, checkTupSize ) +import DynFlags ( DynFlag(..) ) +import BasicTypes ( FixityDirection(..) ) +import PrelNames ( thFAKE, hasKey, assertIdKey, assertErrorName, + loopAName, choiceAName, appAName, arrAName, composeAName, firstAName, + negateName, thenMName, bindMName, failMName ) +import Name ( Name, nameOccName, nameIsLocalOrFrom ) import NameSet -import UnicodeUtil ( stringToUtf8 ) +import RdrName ( RdrName, emptyGlobalRdrEnv, extendLocalRdrEnv, lookupLocalRdrEnv ) +import LoadIface ( loadHomeInterface ) import UniqFM ( isNullUFM ) import UniqSet ( emptyUniqSet ) +import List ( nub ) import Util ( isSingleton ) -import List ( intersectBy, unzip4 ) import ListSetOps ( removeDups ) +import Maybes ( fromJust ) import Outputable +import SrcLoc ( Located(..), unLoc, getLoc, cmpLocated ) import FastString -\end{code} - - -************************************************************************ -* * -\subsection{Match} -* * -************************************************************************ -\begin{code} -rnMatch :: HsMatchContext Name -> RdrNameMatch -> RnM (RenamedMatch, FreeVars) - -rnMatch ctxt match@(Match pats maybe_rhs_sig grhss) - = addSrcLoc (getMatchLoc match) $ - - -- Deal with the rhs type signature - bindPatSigTyVars rhs_sig_tys $ - doptM Opt_GlasgowExts `thenM` \ opt_GlasgowExts -> - (case maybe_rhs_sig of - 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" +import List ( unzip4 ) \end{code} %************************************************************************ %* * -\subsubsection{Guarded right-hand sides (GRHSs)} -%* * -%************************************************************************ - -\begin{code} -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 [ResultStmt _ _] = True - is_standard_guard [ExprStmt _ _ _, ResultStmt _ _] = True - is_standard_guard other = False -\end{code} - -%************************************************************************ -%* * \subsubsection{Expressions} %* * %************************************************************************ \begin{code} -rnExprs :: [RdrNameHsExpr] -> RnM ([RenamedHsExpr], FreeVars) +rnExprs :: [LHsExpr RdrName] -> RnM ([LHsExpr Name], FreeVars) rnExprs ls = rnExprs' ls emptyUniqSet where rnExprs' [] acc = returnM ([], acc) rnExprs' (expr:exprs) acc - = rnExpr expr `thenM` \ (expr', fvExpr) -> + = rnLExpr 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 @@ -157,13 +81,19 @@ grubby_seqNameSet ns result | isNullUFM ns = result Variables. We look up the variable and return the resulting name. \begin{code} -rnExpr :: RdrNameHsExpr -> RnM (RenamedHsExpr, FreeVars) +rnLExpr :: LHsExpr RdrName -> RnM (LHsExpr Name, FreeVars) +rnLExpr = wrapLocFstM rnExpr + +rnExpr :: HsExpr RdrName -> RnM (HsExpr Name, FreeVars) rnExpr (HsVar v) = lookupOccRn v `thenM` \ name -> - if name `hasKey` assertIdKey && not opt_IgnoreAsserts then + doptM Opt_IgnoreAsserts `thenM` \ ignore_asserts -> + if name `hasKey` assertIdKey && not ignore_asserts then -- We expand it to (GHC.Err.assertError location_string) - mkAssertErrorExpr + mkAssertErrorExpr `thenM` \ (e, fvs) -> + returnM (e, fvs `addOneFV` name) + -- Keep 'assert' as a free var, to ensure it's not reported as unused! else -- The normal case. Even if the Id was 'assert', if we are -- ignoring assertions we leave it as GHC.Base.assert; @@ -171,147 +101,98 @@ rnExpr (HsVar v) returnM (HsVar name, unitFV name) rnExpr (HsIPVar v) - = newIPName v `thenM` \ name -> - let - fvs = case name of - Linear _ -> mkFVs [splitName, fstName, sndName] - Dupable _ -> emptyFVs - in - returnM (HsIPVar name, fvs) + = newIPNameRn v `thenM` \ name -> + returnM (HsIPVar name, emptyFVs) rnExpr (HsLit lit) - = litFVs lit `thenM` \ fvs -> - returnM (HsLit lit, fvs) + = rnLit lit `thenM_` + returnM (HsLit lit, emptyFVs) rnExpr (HsOverLit lit) = rnOverLit lit `thenM` \ (lit', fvs) -> returnM (HsOverLit lit', fvs) -rnExpr (HsLam match) - = rnMatch LambdaExpr match `thenM` \ (match', fvMatch) -> - returnM (HsLam match', fvMatch) - rnExpr (HsApp fun arg) - = rnExpr fun `thenM` \ (fun',fvFun) -> - rnExpr arg `thenM` \ (arg',fvArg) -> + = rnLExpr fun `thenM` \ (fun',fvFun) -> + rnLExpr arg `thenM` \ (arg',fvArg) -> returnM (HsApp fun' arg', fvFun `plusFV` fvArg) rnExpr (OpApp e1 op _ e2) - = rnExpr e1 `thenM` \ (e1', fv_e1) -> - rnExpr e2 `thenM` \ (e2', fv_e2) -> - rnExpr op `thenM` \ (op'@(HsVar op_name), fv_op) -> + = rnLExpr e1 `thenM` \ (e1', fv_e1) -> + rnLExpr e2 `thenM` \ (e2', fv_e2) -> + rnLExpr op `thenM` \ (op'@(L _ (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 `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 -> + -- we used to avoid fixity stuff, but we can't easily tell any + -- more, so I've removed the test. Adding HsPars in TcGenDeriv + -- should prevent bad things happening. + lookupFixityRn op_name `thenM` \ fixity -> + mkOpAppRn e1' op' fixity e2' `thenM` \ final_e -> returnM (final_e, fv_e1 `plusFV` fv_op `plusFV` fv_e2) rnExpr (NegApp e _) - = rnExpr e `thenM` \ (e', fv_e) -> + = rnLExpr 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 `thenM` \ (e', fvs_e) -> + = rnLExpr 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 +-- Don't ifdef-GHCI them because we want to fail gracefully +-- (not with an rnExpr crash) in a stage-1 compiler. +rnExpr e@(HsBracket br_body) + = checkTH e "bracket" `thenM_` + rnBracket br_body `thenM` \ (body', fvs_e) -> + returnM (HsBracket body', fvs_e) + +rnExpr e@(HsSpliceE splice) + = rnSplice splice `thenM` \ (splice', fvs) -> + returnM (HsSpliceE splice', fvs) rnExpr section@(SectionL expr op) - = rnExpr expr `thenM` \ (expr', fvs_expr) -> - rnExpr op `thenM` \ (op', fvs_op) -> + = rnLExpr expr `thenM` \ (expr', fvs_expr) -> + rnLExpr 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 `thenM` \ (op', fvs_op) -> - rnExpr expr `thenM` \ (expr', fvs_expr) -> + = rnLExpr op `thenM` \ (op', fvs_op) -> + rnLExpr 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 _) - -- Check out the comment on RnIfaces.getNonWiredDataDecl about ccalls - = rnExprs args `thenM` \ (args', fvs_args) -> - returnM (HsCCall fun args' may_gc is_casm placeHolderType, - fvs_args `plusFV` mkFVs [cCallableClassName, - cReturnableClassName, - ioDataConName]) +rnExpr (HsCoreAnn ann expr) + = rnLExpr expr `thenM` \ (expr', fvs_expr) -> + returnM (HsCoreAnn ann expr', fvs_expr) rnExpr (HsSCC lbl expr) - = rnExpr expr `thenM` \ (expr', fvs_expr) -> + = rnLExpr expr `thenM` \ (expr', fvs_expr) -> returnM (HsSCC lbl expr', fvs_expr) -rnExpr (HsCase expr ms src_loc) - = 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 (HsLam matches) + = rnMatchGroup LambdaExpr matches `thenM` \ (matches', fvMatch) -> + returnM (HsLam matches', fvMatch) + +rnExpr (HsCase expr matches) + = rnLExpr expr `thenM` \ (new_expr, e_fvs) -> + rnMatchGroup CaseAlt matches `thenM` \ (new_matches, ms_fvs) -> + returnM (HsCase new_expr new_matches, e_fvs `plusFV` ms_fvs) rnExpr (HsLet binds expr) - = rnBindsAndThen binds $ \ binds' -> - rnExpr expr `thenM` \ (expr',fvExpr) -> + = rnLocalBindsAndThen binds $ \ binds' -> + rnLExpr 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_` - - -- Generate the rebindable syntax for the monad - mapAndUnzipM lookupSyntaxName - (syntax_names do_or_lc) `thenM` \ (monad_names', monad_fvs) -> - - returnM (HsDo do_or_lc stmts' monad_names' placeHolderType src_loc, - fvs `plusFV` implicit_fvs do_or_lc `plusFV` plusFVs monad_fvs) - where - 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 e@(HsDo do_or_lc stmts body _) + = do { ((stmts', body'), fvs) <- rnStmts do_or_lc stmts $ + rnLExpr body + ; return (HsDo do_or_lc stmts' body' placeHolderType, fvs) } rnExpr (ExplicitList _ exps) = rnExprs exps `thenM` \ (exps', fvs) -> @@ -319,8 +200,7 @@ rnExpr (ExplicitList _ exps) rnExpr (ExplicitPArr _ exps) = rnExprs exps `thenM` \ (exps', fvs) -> - returnM (ExplicitPArr placeHolderType exps', - fvs `addOneFV` toPName `addOneFV` parrTyCon_name) + returnM (ExplicitPArr placeHolderType exps', fvs) rnExpr e@(ExplicitTuple exps boxity) = checkTupSize tup_size `thenM_` @@ -330,29 +210,30 @@ rnExpr e@(ExplicitTuple exps boxity) tup_size = length exps tycon_name = tupleTyCon_name boxity tup_size -rnExpr (RecordCon con_id rbinds) - = lookupOccRn con_id `thenM` \ conname -> +rnExpr (RecordCon con_id _ rbinds) + = lookupLocatedOccRn con_id `thenM` \ conname -> rnRbinds "construction" rbinds `thenM` \ (rbinds', fvRbinds) -> - returnM (RecordCon conname rbinds', fvRbinds `addOneFV` conname) + returnM (RecordCon conname noPostTcExpr rbinds', + fvRbinds `addOneFV` unLoc conname) -rnExpr (RecordUpd expr rbinds) - = rnExpr expr `thenM` \ (expr', fvExpr) -> +rnExpr (RecordUpd expr rbinds _ _) + = rnLExpr expr `thenM` \ (expr', fvExpr) -> rnRbinds "update" rbinds `thenM` \ (rbinds', fvRbinds) -> - returnM (RecordUpd expr' rbinds', fvExpr `plusFV` fvRbinds) + returnM (RecordUpd expr' rbinds' placeHolderType placeHolderType, + fvExpr `plusFV` fvRbinds) rnExpr (ExprWithTySig expr pty) - = rnExpr expr `thenM` \ (expr', fvExpr) -> + = rnLExpr 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) - = 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 (HsIf p b1 b2) + = rnLExpr p `thenM` \ (p', fvP) -> + rnLExpr b1 `thenM` \ (b1', fvB1) -> + rnLExpr b2 `thenM` \ (b2', fvB2) -> + returnM (HsIf p' b1' b2', plusFVs [fvP, fvB1, fvB2]) rnExpr (HsType a) = rnHsTypeFVs doc a `thenM` \ (t, fvT) -> @@ -360,14 +241,13 @@ rnExpr (HsType a) where doc = text "In a type argument" -rnExpr (ArithSeqIn seq) +rnExpr (ArithSeq _ seq) = rnArithSeq seq `thenM` \ (new_seq, fvs) -> - returnM (ArithSeqIn new_seq, fvs `addOneFV` enumClassName) + returnM (ArithSeq noPostTcExpr new_seq, fvs) -rnExpr (PArrSeqIn seq) +rnExpr (PArrSeq _ seq) = rnArithSeq seq `thenM` \ (new_seq, fvs) -> - returnM (PArrSeqIn new_seq, - fvs `plusFV` mkFVs [enumFromToPName, enumFromThenToPName]) + returnM (PArrSeq noPostTcExpr new_seq, fvs) \end{code} These three are pattern syntax appearing in expressions. @@ -375,16 +255,213 @@ Since all the symbols are reservedops we can simply reject them. We return a (bogus) EWildPat in each case. \begin{code} -rnExpr e@EWildPat = addErr (patSynErr e) `thenM_` - returnM (EWildPat, emptyFVs) +rnExpr e@EWildPat = patSynErr e +rnExpr e@(EAsPat {}) = patSynErr e +rnExpr e@(ELazyPat {}) = patSynErr e +\end{code} + +%************************************************************************ +%* * + Arrow notation +%* * +%************************************************************************ + +\begin{code} +rnExpr (HsProc pat body) + = newArrowScope $ + rnPatsAndThen ProcExpr [pat] $ \ [pat'] -> + rnCmdTop body `thenM` \ (body',fvBody) -> + returnM (HsProc pat' body', fvBody) + +rnExpr (HsArrApp arrow arg _ ho rtl) + = select_arrow_scope (rnLExpr arrow) `thenM` \ (arrow',fvArrow) -> + rnLExpr arg `thenM` \ (arg',fvArg) -> + returnM (HsArrApp arrow' arg' placeHolderType ho rtl, + fvArrow `plusFV` fvArg) + where + select_arrow_scope tc = case ho of + HsHigherOrderApp -> tc + HsFirstOrderApp -> escapeArrowScope tc + +-- infix form +rnExpr (HsArrForm op (Just _) [arg1, arg2]) + = escapeArrowScope (rnLExpr op) + `thenM` \ (op'@(L _ (HsVar op_name)),fv_op) -> + rnCmdTop arg1 `thenM` \ (arg1',fv_arg1) -> + rnCmdTop arg2 `thenM` \ (arg2',fv_arg2) -> + + -- Deal with fixity -rnExpr e@(EAsPat _ _) = addErr (patSynErr e) `thenM_` - returnM (EWildPat, emptyFVs) + lookupFixityRn op_name `thenM` \ fixity -> + mkOpFormRn arg1' op' fixity arg2' `thenM` \ final_e -> -rnExpr e@(ELazyPat _) = addErr (patSynErr e) `thenM_` - returnM (EWildPat, emptyFVs) + returnM (final_e, + fv_arg1 `plusFV` fv_op `plusFV` fv_arg2) + +rnExpr (HsArrForm op fixity cmds) + = escapeArrowScope (rnLExpr op) `thenM` \ (op',fvOp) -> + rnCmdArgs cmds `thenM` \ (cmds',fvCmds) -> + returnM (HsArrForm op' fixity cmds', fvOp `plusFV` fvCmds) + +rnExpr other = pprPanic "rnExpr: unexpected expression" (ppr other) + -- DictApp, DictLam, TyApp, TyLam \end{code} + +%************************************************************************ +%* * + Arrow commands +%* * +%************************************************************************ + +\begin{code} +rnCmdArgs [] = returnM ([], emptyFVs) +rnCmdArgs (arg:args) + = rnCmdTop arg `thenM` \ (arg',fvArg) -> + rnCmdArgs args `thenM` \ (args',fvArgs) -> + returnM (arg':args', fvArg `plusFV` fvArgs) + + +rnCmdTop = wrapLocFstM rnCmdTop' + where + rnCmdTop' (HsCmdTop cmd _ _ _) + = rnLExpr (convertOpFormsLCmd cmd) `thenM` \ (cmd', fvCmd) -> + let + cmd_names = [arrAName, composeAName, firstAName] ++ + nameSetToList (methodNamesCmd (unLoc cmd')) + in + -- Generate the rebindable syntax for the monad + lookupSyntaxTable cmd_names `thenM` \ (cmd_names', cmd_fvs) -> + + returnM (HsCmdTop cmd' [] placeHolderType cmd_names', + fvCmd `plusFV` cmd_fvs) + +--------------------------------------------------- +-- convert OpApp's in a command context to HsArrForm's + +convertOpFormsLCmd :: LHsCmd id -> LHsCmd id +convertOpFormsLCmd = fmap convertOpFormsCmd + +convertOpFormsCmd :: HsCmd id -> HsCmd id + +convertOpFormsCmd (HsApp c e) = HsApp (convertOpFormsLCmd c) e +convertOpFormsCmd (HsLam match) = HsLam (convertOpFormsMatch match) +convertOpFormsCmd (OpApp c1 op fixity c2) + = let + arg1 = L (getLoc c1) $ HsCmdTop (convertOpFormsLCmd c1) [] placeHolderType [] + arg2 = L (getLoc c2) $ HsCmdTop (convertOpFormsLCmd c2) [] placeHolderType [] + in + HsArrForm op (Just fixity) [arg1, arg2] + +convertOpFormsCmd (HsPar c) = HsPar (convertOpFormsLCmd c) + +-- gaw 2004 +convertOpFormsCmd (HsCase exp matches) + = HsCase exp (convertOpFormsMatch matches) + +convertOpFormsCmd (HsIf exp c1 c2) + = HsIf exp (convertOpFormsLCmd c1) (convertOpFormsLCmd c2) + +convertOpFormsCmd (HsLet binds cmd) + = HsLet binds (convertOpFormsLCmd cmd) + +convertOpFormsCmd (HsDo ctxt stmts body ty) + = HsDo ctxt (map (fmap convertOpFormsStmt) stmts) + (convertOpFormsLCmd body) ty + +-- Anything else is unchanged. This includes HsArrForm (already done), +-- things with no sub-commands, and illegal commands (which will be +-- caught by the type checker) +convertOpFormsCmd c = c + +convertOpFormsStmt (BindStmt pat cmd _ _) + = BindStmt pat (convertOpFormsLCmd cmd) noSyntaxExpr noSyntaxExpr +convertOpFormsStmt (ExprStmt cmd _ _) + = ExprStmt (convertOpFormsLCmd cmd) noSyntaxExpr placeHolderType +convertOpFormsStmt (RecStmt stmts lvs rvs es binds) + = RecStmt (map (fmap convertOpFormsStmt) stmts) lvs rvs es binds +convertOpFormsStmt stmt = stmt + +convertOpFormsMatch (MatchGroup ms ty) + = MatchGroup (map (fmap convert) ms) ty + where convert (Match pat mty grhss) + = Match pat mty (convertOpFormsGRHSs grhss) + +convertOpFormsGRHSs (GRHSs grhss binds) + = GRHSs (map convertOpFormsGRHS grhss) binds + +convertOpFormsGRHS = fmap convert + where + convert (GRHS stmts cmd) = GRHS stmts (convertOpFormsLCmd cmd) + +--------------------------------------------------- +type CmdNeeds = FreeVars -- Only inhabitants are + -- appAName, choiceAName, loopAName + +-- find what methods the Cmd needs (loop, choice, apply) +methodNamesLCmd :: LHsCmd Name -> CmdNeeds +methodNamesLCmd = methodNamesCmd . unLoc + +methodNamesCmd :: HsCmd Name -> CmdNeeds + +methodNamesCmd cmd@(HsArrApp _arrow _arg _ HsFirstOrderApp _rtl) + = emptyFVs +methodNamesCmd cmd@(HsArrApp _arrow _arg _ HsHigherOrderApp _rtl) + = unitFV appAName +methodNamesCmd cmd@(HsArrForm {}) = emptyFVs + +methodNamesCmd (HsPar c) = methodNamesLCmd c + +methodNamesCmd (HsIf p c1 c2) + = methodNamesLCmd c1 `plusFV` methodNamesLCmd c2 `addOneFV` choiceAName + +methodNamesCmd (HsLet b c) = methodNamesLCmd c + +methodNamesCmd (HsDo sc stmts body ty) + = methodNamesStmts stmts `plusFV` methodNamesLCmd body + +methodNamesCmd (HsApp c e) = methodNamesLCmd c + +methodNamesCmd (HsLam match) = methodNamesMatch match + +methodNamesCmd (HsCase scrut matches) + = methodNamesMatch matches `addOneFV` choiceAName + +methodNamesCmd other = emptyFVs + -- Other forms can't occur in commands, but it's not convenient + -- to error here so we just do what's convenient. + -- The type checker will complain later + +--------------------------------------------------- +methodNamesMatch (MatchGroup ms ty) + = plusFVs (map do_one ms) + where + do_one (L _ (Match pats sig_ty grhss)) = methodNamesGRHSs grhss + +------------------------------------------------- +-- gaw 2004 +methodNamesGRHSs (GRHSs grhss binds) = plusFVs (map methodNamesGRHS grhss) + +------------------------------------------------- +methodNamesGRHS (L _ (GRHS stmts rhs)) = methodNamesLCmd rhs + +--------------------------------------------------- +methodNamesStmts stmts = plusFVs (map methodNamesLStmt stmts) + +--------------------------------------------------- +methodNamesLStmt = methodNamesStmt . unLoc + +methodNamesStmt (ExprStmt cmd _ _) = methodNamesLCmd cmd +methodNamesStmt (BindStmt pat cmd _ _) = methodNamesLCmd cmd +methodNamesStmt (RecStmt stmts _ _ _ _) + = methodNamesStmts stmts `addOneFV` loopAName +methodNamesStmt (LetStmt b) = emptyFVs +methodNamesStmt (ParStmt ss) = emptyFVs + -- ParStmt can't occur in commands, but it's not convenient to error + -- here so we just do what's convenient +\end{code} + + %************************************************************************ %* * Arithmetic sequences @@ -393,23 +470,23 @@ rnExpr e@(ELazyPat _) = addErr (patSynErr e) `thenM_` \begin{code} rnArithSeq (From expr) - = rnExpr expr `thenM` \ (expr', fvExpr) -> + = rnLExpr expr `thenM` \ (expr', fvExpr) -> returnM (From expr', fvExpr) rnArithSeq (FromThen expr1 expr2) - = rnExpr expr1 `thenM` \ (expr1', fvExpr1) -> - rnExpr expr2 `thenM` \ (expr2', fvExpr2) -> + = rnLExpr expr1 `thenM` \ (expr1', fvExpr1) -> + rnLExpr 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) -> + = rnLExpr expr1 `thenM` \ (expr1', fvExpr1) -> + rnLExpr 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) -> + = rnLExpr expr1 `thenM` \ (expr1', fvExpr1) -> + rnLExpr expr2 `thenM` \ (expr2', fvExpr2) -> + rnLExpr expr3 `thenM` \ (expr3', fvExpr3) -> returnM (FromThenTo expr1' expr2' expr3', plusFVs [fvExpr1, fvExpr2, fvExpr3]) \end{code} @@ -427,14 +504,14 @@ rnRbinds str rbinds mapFvRn rn_rbind rbinds `thenM` \ (rbinds', fvRbind) -> returnM (rbinds', fvRbind) where - (_, dup_fields) = removeDups compare [ f | (f,_) <- rbinds ] + (_, dup_fields) = removeDups cmpLocated [ f | (f,_) <- rbinds ] - field_dup_err dups = addErr (dupFieldErr str dups) + field_dup_err dups = mappM_ (\f -> addLocErr f (dupFieldErr str)) dups rn_rbind (field, expr) - = lookupGlobalOccRn field `thenM` \ fieldname -> - rnExpr expr `thenM` \ (expr', fvExpr) -> - returnM ((fieldname, expr'), fvExpr `addOneFV` fieldname) + = lookupLocatedGlobalOccRn field `thenM` \ fieldname -> + rnLExpr expr `thenM` \ (expr', fvExpr) -> + returnM ((fieldname, expr'), fvExpr `addOneFV` unLoc fieldname) \end{code} %************************************************************************ @@ -444,24 +521,56 @@ rnRbinds str rbinds %************************************************************************ \begin{code} -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) +rnBracket (VarBr n) = do { name <- lookupOccRn n + ; this_mod <- getModule + ; checkM (nameIsLocalOrFrom this_mod name) $ -- Reason: deprecation checking asumes the + do { loadHomeInterface msg name -- home interface is loaded, and this is the + ; return () } -- only way that is going to happen + ; returnM (VarBr name, unitFV name) } + where + msg = ptext SLIT("Need interface for Template Haskell quoted Name") + +rnBracket (ExpBr e) = do { (e', fvs) <- rnLExpr e + ; return (ExpBr e', fvs) } +rnBracket (PatBr p) = do { (p', fvs) <- rnLPat p + ; return (PatBr p', fvs) } +rnBracket (TypBr t) = do { (t', fvs) <- rnHsTypeFVs doc t + ; return (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) + = do { gbl_env <- getGblEnv + + ; let gbl_env1 = gbl_env { tcg_mod = thFAKE } + -- Note the thFAKE. The top-level names from the bracketed + -- declarations will go into the name cache, and we don't want them to + -- confuse the Names for the current module. + -- By using a pretend module, thFAKE, we keep them safely out of the way. + + ; names <- getLocalDeclBinders gbl_env1 group + ; rdr_env' <- extendRdrEnvRn emptyGlobalRdrEnv names + -- Furthermore, the names in the bracket shouldn't conflict with + -- existing top-level names E.g. + -- foo = 1 + -- bar = [d| foo = 1|] + -- But both 'foo's get a LocalDef provenance, so we'd get a complaint unless + -- we start with an emptyGlobalRdrEnv + + ; setGblEnv (gbl_env { tcg_rdr_env = tcg_rdr_env gbl_env1 `plusOccEnv` rdr_env', + tcg_dus = emptyDUs }) $ do + -- Notice plusOccEnv, not plusGlobalRdrEnv. In this situation we want + -- to *shadow* top-level bindings. (See the 'foo' example above.) + -- If we don't shadow, we'll get an ambiguity complaint when we do + -- a lookupTopBndrRn (which uses lookupGreLocalRn) on the binder of the 'foo' + -- + -- Furthermore, arguably if the splice does define foo, that should hide + -- any foo's further out + -- + -- The emptyDUs is so that we just collect uses for this group alone + + { (tcg_env, group') <- rnSrcDecls group + -- Discard the tcg_env; it contains only extra info about fixity + ; return (DecBr group', allUses (tcg_dus tcg_env)) } } \end{code} %************************************************************************ @@ -471,167 +580,240 @@ rnBracket (DecBr group) %************************************************************************ \begin{code} -rnStmts :: HsStmtContext Name -> [RdrNameStmt] -> RnM ([RenamedStmt], FreeVars) +rnStmts :: HsStmtContext Name -> [LStmt RdrName] + -> RnM (thing, FreeVars) + -> RnM (([LStmt Name], thing), FreeVars) -rnStmts MDoExpr stmts = rnMDoStmts stmts -rnStmts ctxt stmts = rnNormalStmts ctxt stmts +rnStmts (MDoExpr _) = rnMDoStmts +rnStmts ctxt = rnNormalStmts ctxt -rnNormalStmts :: HsStmtContext Name -> [RdrNameStmt] -> RnM ([RenamedStmt], FreeVars) +rnNormalStmts :: HsStmtContext Name -> [LStmt RdrName] + -> RnM (thing, FreeVars) + -> RnM (([LStmt Name], thing), 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)) +rnNormalStmts ctxt [] thing_inside + = do { (thing, fvs) <- thing_inside + ; return (([],thing), fvs) } + +rnNormalStmts ctxt (L loc stmt : stmts) thing_inside + = do { ((stmt', (stmts', thing)), fvs) + <- rnStmt ctxt stmt $ + rnNormalStmts ctxt stmts thing_inside + ; return (((L loc stmt' : stmts'), thing), fvs) } + +rnStmt :: HsStmtContext Name -> Stmt RdrName + -> RnM (thing, FreeVars) + -> RnM ((Stmt Name, thing), FreeVars) + +rnStmt ctxt (ExprStmt expr _ _) thing_inside + = do { (expr', fv_expr) <- rnLExpr expr + ; (then_op, fvs1) <- lookupSyntaxName thenMName + ; (thing, fvs2) <- thing_inside + ; return ((ExprStmt expr' then_op placeHolderType, thing), + fv_expr `plusFV` fvs1 `plusFV` fvs2) } + +rnStmt ctxt (BindStmt pat expr _ _) thing_inside + = do { (expr', fv_expr) <- rnLExpr expr + -- The binders do not scope over the expression + ; (bind_op, fvs1) <- lookupSyntaxName bindMName + ; (fail_op, fvs2) <- lookupSyntaxName failMName + ; rnPatsAndThen (StmtCtxt ctxt) [pat] $ \ [pat'] -> do + { (thing, fvs3) <- thing_inside + ; return ((BindStmt pat' expr' bind_op fail_op, thing), + fv_expr `plusFV` fvs1 `plusFV` fvs2 `plusFV` fvs3) }} + -- fv_expr shouldn't really be filtered by the rnPatsAndThen + -- but it does not matter because the names are unique + +rnStmt ctxt (LetStmt binds) thing_inside + = do { checkErr (ok ctxt binds) + (badIpBinds (ptext SLIT("a parallel list comprehension:")) binds) + ; rnLocalBindsAndThen binds $ \ binds' -> do + { (thing, fvs) <- thing_inside + ; return ((LetStmt binds', thing), 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 (ParStmtCtxt _) (HsIPBinds _) = False ok _ _ = True -rnNormalStmts ctxt (ParStmt stmtss : stmts) - = mapFvRn (rnNormalStmts (ParStmtCtxt ctxt)) stmtss `thenM` \ (stmtss', fv_stmtss) -> +rnStmt ctxt (RecStmt rec_stmts _ _ _ _) thing_inside + = bindLocatedLocalsRn doc (collectLStmtsBinders rec_stmts) $ \ bndrs -> + rn_rec_stmts bndrs rec_stmts `thenM` \ segs -> + thing_inside `thenM` \ (thing, fvs) -> 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) - + segs_w_fwd_refs = addFwdRefs segs + (ds, us, fs, rec_stmts') = unzip4 segs_w_fwd_refs + later_vars = nameSetToList (plusFVs ds `intersectNameSet` fvs) + fwd_vars = nameSetToList (plusFVs fs) + uses = plusFVs us + rec_stmt = RecStmt rec_stmts' later_vars fwd_vars [] emptyLHsBinds + in + returnM ((rec_stmt, thing), uses `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) + doc = text "In a recursive do statement" + +rnStmt ctxt (ParStmt segs) thing_inside + = do { opt_GlasgowExts <- doptM Opt_GlasgowExts + ; checkM opt_GlasgowExts parStmtErr + ; orig_lcl_env <- getLocalRdrEnv + ; ((segs',thing), fvs) <- go orig_lcl_env [] segs + ; return ((ParStmt segs', thing), fvs) } + where +-- type ParSeg id = [([LStmt id], [id])] +-- go :: NameSet -> [ParSeg RdrName] +-- -> RnM (([ParSeg Name], thing), FreeVars) + + go orig_lcl_env bndrs [] + = do { let { (bndrs', dups) = removeDups cmpByOcc bndrs + ; inner_env = extendLocalRdrEnv orig_lcl_env bndrs' } + ; mappM dupErr dups + ; (thing, fvs) <- setLocalRdrEnv inner_env thing_inside + ; return (([], thing), fvs) } + + go orig_lcl_env bndrs_so_far ((stmts, _) : segs) + = do { ((stmts', (bndrs, segs', thing)), fvs) + <- rnNormalStmts par_ctxt stmts $ do + { -- Find the Names that are bound by stmts + lcl_env <- getLocalRdrEnv + ; let { rdr_bndrs = collectLStmtsBinders stmts + ; bndrs = map ( fromJust + . lookupLocalRdrEnv lcl_env + . unLoc) rdr_bndrs + ; new_bndrs = nub bndrs ++ bndrs_so_far + -- The nub is because there might be shadowing + -- x <- e1; x <- e2 + -- So we'll look up (Unqual x) twice, getting + -- the second binding both times, which is the + } -- one we want + + -- Typecheck the thing inside, passing on all + -- the Names bound, but separately; revert the envt + ; ((segs', thing), fvs) <- setLocalRdrEnv orig_lcl_env $ + go orig_lcl_env new_bndrs segs + + -- Figure out which of the bound names are used + ; let used_bndrs = filter (`elemNameSet` fvs) bndrs + ; return ((used_bndrs, segs', thing), fvs) } + + ; let seg' = (stmts', bndrs) + ; return (((seg':segs'), thing), + delListFromNameSet fvs bndrs) } + + par_ctxt = ParStmtCtxt ctxt + + cmpByOcc n1 n2 = nameOccName n1 `compare` nameOccName n2 + dupErr vs = addErr (ptext SLIT("Duplicate binding in parallel list comprehension for:") + <+> quotes (ppr (head vs))) \end{code} %************************************************************************ %* * -\subsubsection{Precedence Parsing} +\subsubsection{mdo expressions} %* * %************************************************************************ \begin{code} -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 +type Segment stmts = (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]) + stmts) -- Either Stmt or [Stmt] + ---------------------------------------------------- -rnMDoStmts :: [RdrNameStmt] -> RnM ([RenamedStmt], FreeVars) -rnMDoStmts stmts +rnMDoStmts :: [LStmt RdrName] + -> RnM (thing, FreeVars) + -> RnM (([LStmt Name], thing), FreeVars) +rnMDoStmts stmts thing_inside = -- Step1: bring all the binders of the mdo into scope - bindLocalsRn doc (collectStmtsBinders stmts) $ \ _ -> - + -- Remember that this also removes the binders from the + -- finally-returned free-vars + bindLocatedLocalsRn doc (collectLStmtsBinders stmts) $ \ bndrs -> + do { -- 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 + -- (This set may not be empty, because we're in a recursive + -- context.) + segs <- rn_rec_stmts bndrs stmts + + ; (thing, fvs_later) <- thing_inside + + ; 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 + 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 + 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 + (stmts', fvs) = segsToStmts grouped_segs fvs_later + + ; return ((stmts', thing), fvs) } where - doc = text "In a mdo-expression" + doc = text "In a recursive mdo-expression" + +--------------------------------------------- +rn_rec_stmts :: [Name] -> [LStmt RdrName] -> RnM [Segment (LStmt Name)] +rn_rec_stmts bndrs stmts = mappM (rn_rec_stmt bndrs) stmts `thenM` \ segs_s -> + returnM (concat segs_s) ---------------------------------------------------- -rn_mdo_stmt :: RdrNameStmt -> RnM Segment +rn_rec_stmt :: [Name] -> LStmt RdrName -> RnM [Segment (LStmt Name)] + -- Rename a Stmt that is inside a RecStmt (or mdo) -- 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) -> +rn_rec_stmt all_bndrs (L loc (ExprStmt expr _ _)) + = rnLExpr expr `thenM` \ (expr', fvs) -> + lookupSyntaxName thenMName `thenM` \ (then_op, fvs1) -> + returnM [(emptyNameSet, fvs `plusFV` fvs1, emptyNameSet, + L loc (ExprStmt expr' then_op placeHolderType))] + +rn_rec_stmt all_bndrs (L loc (BindStmt pat expr _ _)) + = rnLExpr expr `thenM` \ (expr', fv_expr) -> + rnLPat pat `thenM` \ (pat', fv_pat) -> + lookupSyntaxName bindMName `thenM` \ (bind_op, fvs1) -> + lookupSyntaxName failMName `thenM` \ (fail_op, fvs2) -> let bndrs = mkNameSet (collectPatBinders pat') - fvs = fv_expr `plusFV` fv_pat + fvs = fv_expr `plusFV` fv_pat `plusFV` fvs1 `plusFV` fvs2 in - returnM (bndrs, fvs, bndrs `intersectNameSet` fvs, - [BindStmt pat' expr' src_loc]) + returnM [(bndrs, fvs, bndrs `intersectNameSet` fvs, + L loc (BindStmt pat' expr' bind_op fail_op))] + +rn_rec_stmt all_bndrs (L loc (LetStmt binds@(HsIPBinds _))) + = do { addErr (badIpBinds (ptext SLIT("an mdo expression")) binds) + ; failM } -rn_mdo_stmt (LetStmt binds) - = rnBinds binds `thenM` \ (binds', fv_binds) -> - returnM (mkNameSet (collectHsBinders binds'), - fv_binds, emptyNameSet, [LetStmt binds']) +rn_rec_stmt all_bndrs (L loc (LetStmt (HsValBinds binds))) + = rnValBinds (trimWith all_bndrs) binds `thenM` \ (binds', du_binds) -> + returnM [(duDefs du_binds, duUses du_binds, + emptyNameSet, L loc (LetStmt (HsValBinds binds')))] -rn_mdo_stmt stmt@(ParStmt _) -- Syntactically illegal in mdo - = pprPanic "rn_mdo_stmt" (ppr stmt) +rn_rec_stmt all_bndrs (L loc (RecStmt stmts _ _ _ _)) -- Flatten Rec inside Rec + = rn_rec_stmts all_bndrs stmts +rn_rec_stmt all_bndrs stmt@(L _ (ParStmt _)) -- Syntactically illegal in mdo + = pprPanic "rn_rec_stmt" (ppr stmt) -addFwdRefs :: [Segment] -> [Segment] +--------------------------------------------- +addFwdRefs :: [Segment a] -> [Segment a] -- 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 @@ -639,12 +821,12 @@ addFwdRefs :: [Segment] -> [Segment] addFwdRefs pairs = fst (foldr mk_seg ([], emptyNameSet) pairs) where - mk_seg (defs, uses, fwds, stmts) (segs, seg_defs) + mk_seg (defs, uses, fwds, stmts) (segs, later_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) + all_defs = later_defs `unionNameSets` defs + new_fwds = fwds `unionNameSets` (uses `intersectNameSet` later_defs) -- Add the downstream fwd refs here ---------------------------------------------------- @@ -682,10 +864,10 @@ addFwdRefs pairs -- q <- x ; z <- y } ; -- r <- x } -glomSegments :: [Segment] -> [Segment] +glomSegments :: [Segment (LStmt Name)] -> [Segment [LStmt Name]] -glomSegments [seg] = [seg] -glomSegments ((defs,uses,fwds,stmts) : segs) +glomSegments [] = [] +glomSegments ((defs,uses,fwds,stmt) : segs) -- Actually stmts will always be a singleton = (seg_defs, seg_uses, seg_fwds, seg_stmts) : others where @@ -696,12 +878,12 @@ glomSegments ((defs,uses,fwds,stmts) : segs) seg_defs = plusFVs ds `plusFV` defs seg_uses = plusFVs us `plusFV` uses seg_fwds = plusFVs fs `plusFV` fwds - seg_stmts = stmts ++ concat ss + seg_stmts = stmt : concat ss grab :: NameSet -- The client - -> [Segment] - -> ([Segment], -- Needed by the 'client' - [Segment]) -- Not needed by the client + -> [Segment a] + -> ([Segment a], -- Needed by the 'client' + [Segment a]) -- Not needed by the client -- The result is simply a split of the input grab uses dus = (reverse yeses, reverse noes) @@ -711,183 +893,42 @@ glomSegments ((defs,uses,fwds,stmts) : segs) ---------------------------------------------------- -segsToStmts :: [Segment] -> ([RenamedStmt], FreeVars) - -segsToStmts [] = ([], emptyFVs) -segsToStmts ((defs, uses, fwds, ss) : segs) - = (new_stmt : later_stmts, later_uses `plusFV` uses) +segsToStmts :: [Segment [LStmt Name]] + -> FreeVars -- Free vars used 'later' + -> ([LStmt Name], FreeVars) + +segsToStmts [] fvs_later = ([], fvs_later) +segsToStmts ((defs, uses, fwds, ss) : segs) fvs_later + = ASSERT( not (null ss) ) + (new_stmt : later_stmts, later_uses `plusFV` uses) where - (later_stmts, later_uses) = segsToStmts segs + (later_stmts, later_uses) = segsToStmts segs fvs_later new_stmt | non_rec = head ss - | otherwise = RecStmt rec_names ss [] + | otherwise = L (getLoc (head ss)) $ + RecStmt ss (nameSetToList used_later) (nameSetToList fwds) + [] emptyLHsBinds 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 + non_rec = isSingleton ss && isEmptyNameSet fwds + used_later = defs `intersectNameSet` later_uses + -- The ones needed after the RecStmt \end{code} %************************************************************************ %* * -\subsubsection{Precedence Parsing} -%* * -%************************************************************************ - -@mkOpAppRn@ deals with operator fixities. The argument expressions -are assumed to be already correctly arranged. It needs the fixities -recorded in the OpApp nodes, because fixity info applies to the things -the programmer actually wrote, so you can't find it out from the Name. - -Furthermore, the second argument is guaranteed not to be another -operator application. Why? Because the parser parses all -operator appications left-associatively, EXCEPT negation, which -we need to handle specially. - -\begin{code} -mkOpAppRn :: RenamedHsExpr -- Left operand; already rearranged - -> RenamedHsExpr -> Fixity -- Operator and fixity - -> RenamedHsExpr -- Right operand (not an OpApp, but might - -- be a NegApp) - -> RnM RenamedHsExpr - ---------------------------- --- (e11 `op1` e12) `op2` e2 -mkOpAppRn e1@(OpApp e11 op1 fix1 e12) op2 fix2 e2 - | nofix_error - = addErr (precParseErr (ppr_op op1,fix1) (ppr_op op2,fix2)) `thenM_` - returnM (OpApp e1 op2 fix2 e2) - - | associate_right - = 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_name) op2 fix2 e2 - | nofix_error - = 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 `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 _) -- 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 - ---------------------------- --- Default case -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 - ) - returnM (OpApp e1 op fix e2) - --- Parser left-associates everything, but --- derived instances may have correctly-associated things to --- in the right operarand. So we just check that the right operand is OK -right_op_ok fix1 (OpApp _ _ fix2 _) - = not error_please && associate_right - where - (error_please, associate_right) = compareFixity fix1 fix2 -right_op_ok fix1 other - = True - --- Parser initially makes negation bind more tightly than any other operator -mkNegAppRn neg_arg neg_name - = -#ifdef DEBUG - getModeRn `thenM` \ mode -> - ASSERT( not_op_app mode neg_arg ) -#endif - returnM (NegApp neg_arg neg_name) - -not_op_app SourceMode (OpApp _ _ _ _) = False -not_op_app mode other = True -\end{code} - -\begin{code} -checkPrecMatch :: Bool -> Name -> RenamedMatch -> RnM () - -checkPrecMatch False fn match - = returnM () - -checkPrecMatch True op (Match (p1:p2:_) _ _) - -- True indicates an infix lhs - = getModeRn `thenM` \ mode -> - -- See comments with rnExpr (OpApp ...) - if isInterfaceMode mode - then returnM () - else checkPrec op p1 False `thenM_` - checkPrec op p2 True - -checkPrecMatch True op _ = panic "checkPrecMatch" - -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 && - (op1_dir == InfixR && op_dir == InfixR && right || - op1_dir == InfixL && op_dir == InfixL && not right)) - - info = (ppr_op op, op_fix) - info1 = (ppr_op op1, op1_fix) - (infol, infor) = if right then (info, info1) else (info1, info) - in - checkErr inf_ok (precParseErr infol infor) - -checkPrec op pat right - = returnM () - --- Check precedence of (arg op) or (op arg) respectively --- 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 _ _ -> 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 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} - - -%************************************************************************ -%* * \subsubsection{Assertion utils} %* * %************************************************************************ \begin{code} -mkAssertErrorExpr :: RnM (RenamedHsExpr, FreeVars) +mkAssertErrorExpr :: RnM (HsExpr Name, FreeVars) -- Return an expression for (assertError "Foo.hs:27") mkAssertErrorExpr - = getSrcLocM `thenM` \ sloc -> + = getSrcSpanM `thenM` \ sloc -> let - expr = HsApp (HsVar assertErrorName) (HsLit msg) - msg = HsStringPrim (mkFastString (stringToUtf8 (showSDoc (ppr sloc)))) + expr = HsApp (L sloc (HsVar assertErrorName)) (L sloc (HsLit msg)) + msg = HsStringPrim (mkFastString (showSDoc (ppr sloc))) in - returnM (expr, unitFV assertErrorName) + returnM (expr, emptyFVs) \end{code} %************************************************************************ @@ -897,31 +938,13 @@ mkAssertErrorExpr %************************************************************************ \begin{code} -ppr_op op = quotes (ppr op) -- Here, op can be a Name or a (Var n), where n is a Name -pp_prefix_minus = ptext SLIT("prefix `-'") - -nonStdGuardErr guard - = hang (ptext - SLIT("accepting non-standard pattern guards (-fglasgow-exts to suppress this message)") - ) 4 (ppr guard) - -patSynErr e - = sep [ptext SLIT("Pattern syntax in expression context:"), - nest 4 (ppr e)] - -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" +patSynErr e = do { addErr (sep [ptext SLIT("Pattern syntax in expression context:"), + nest 4 (ppr e)]) + ; return (EWildPat, emptyFVs) } -thErr what - = ptext SLIT("Template Haskell") <+> text what <+> - ptext SLIT("illegal in a stage-1 compiler") +parStmtErr = addErr (ptext SLIT("Illegal parallel list comprehension: use -fglasgow-exts")) -badIpBinds binds - = hang (ptext SLIT("Implicit-parameter bindings illegal in a parallel list comprehension:")) 4 - (ppr binds) +badIpBinds what binds + = hang (ptext SLIT("Implicit-parameter bindings illegal in") <+> what) + 2 (ppr binds) \end{code}