X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnExpr.lhs;h=a4c7e7d3e5cfbc2ca858b3f665ac41253845fe14;hb=f83a5a68edb4b9dbdff1eebeed84527711efc728;hp=613b37be92d35e2bac91607d54ae28d5c8fde047;hpb=7a3bd641457666e10d0a47be9f22762e03defbf0;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnExpr.lhs b/ghc/compiler/rename/RnExpr.lhs index 613b37b..a4c7e7d 100644 --- a/ghc/compiler/rename/RnExpr.lhs +++ b/ghc/compiler/rename/RnExpr.lhs @@ -1,47 +1,54 @@ % -% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996 +% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % \section[RnExpr]{Renaming of expressions} Basically dependency analysis. -Handles @Match@, @GRHSsAndBinds@, @HsExpr@, and @Qualifier@ datatypes. In +Handles @Match@, @GRHSs@, @HsExpr@, and @Qualifier@ datatypes. In general, all of these functions return a renamed thing, and a set of free variables. \begin{code} -#include "HsVersions.h" - module RnExpr ( - rnMatch, rnGRHSsAndBinds, rnPat, + rnMatch, rnGRHSs, rnPat, rnExpr, rnExprs, checkPrecMatch ) where -IMP_Ubiq() -IMPORT_DELOOPER(RnLoop) -- break the RnPass/RnExpr/RnBinds loops +#include "HsVersions.h" + +import {-# SOURCE #-} RnBinds ( rnBinds ) +import {-# SOURCE #-} RnSource ( rnHsSigType, rnHsPolyType, rnHsType ) import HsSyn import RdrHsSyn import RnHsSyn import RnMonad import RnEnv -import PrelInfo ( numClass_RDR, fractionalClass_RDR, eqClass_RDR, ccallableClass_RDR, - creturnableClass_RDR, monadZeroClass_RDR, enumClass_RDR, - negate_RDR +import RnIfaces ( lookupFixity ) +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 ) import TysPrim ( charPrimTyCon, addrPrimTyCon, intPrimTyCon, floatPrimTyCon, doublePrimTyCon ) -import TyCon ( TyCon ) -import ErrUtils ( addErrLoc, addShortErrLocLine ) -import Name -import Pretty -import UniqFM ( lookupUFM{-, ufmToList ToDo:rm-} ) -import UniqSet ( emptyUniqSet, unitUniqSet, - unionUniqSets, unionManyUniqSets, - SYN_IE(UniqSet) +import Name ( nameUnique, isLocallyDefined, NamedThing(..) + , mkSysLocalName, nameSrcLoc ) -import Util ( Ord3(..), removeDups, panic ) +import NameSet +import UniqFM ( isNullUFM ) +import FiniteMap ( elemFM ) +import UniqSet ( emptyUniqSet, UniqSet ) +import Unique ( assertIdKey ) +import Util ( removeDups ) +import ListSetOps ( unionLists ) +import Maybes ( maybeToBool ) +import Outputable \end{code} @@ -52,35 +59,58 @@ import Util ( Ord3(..), removeDups, panic ) ********************************************************* \begin{code} -rnPat :: RdrNamePat -> RnMS s RenamedPat +rnPat :: RdrNamePat -> RnMS (RenamedPat, FreeVars) -rnPat WildPatIn = returnRn WildPatIn +rnPat WildPatIn = returnRn (WildPatIn, emptyFVs) rnPat (VarPatIn name) - = lookupRn name `thenRn` \ vname -> - returnRn (VarPatIn vname) - + = lookupBndrRn name `thenRn` \ vname -> + returnRn (VarPatIn vname, emptyFVs) + +rnPat (SigPatIn pat ty) + | opt_GlasgowExts + = rnPat pat `thenRn` \ (pat', fvs1) -> + rnHsPolyType 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_` - lookupImplicitOccRn eqClass_RDR `thenRn_` -- Needed to find equality on pattern - returnRn (LitPatIn lit) + = litOccurrence lit `thenRn` \ fvs1 -> + lookupImplicitOccRn eqClass_RDR `thenRn` \ eq -> -- Needed to find equality on pattern + returnRn (LitPatIn lit, fvs1 `addOneFV` eq) rnPat (LazyPatIn pat) - = rnPat pat `thenRn` \ pat' -> - returnRn (LazyPatIn pat') + = rnPat pat `thenRn` \ (pat', fvs) -> + returnRn (LazyPatIn pat', fvs) rnPat (AsPatIn name pat) - = rnPat pat `thenRn` \ pat' -> - lookupRn name `thenRn` \ vname -> - returnRn (AsPatIn vname pat') + = rnPat pat `thenRn` \ (pat', fvs) -> + lookupBndrRn name `thenRn` \ vname -> + returnRn (AsPatIn vname pat', fvs) rnPat (ConPatIn con pats) - = lookupRn con `thenRn` \ con' -> - mapRn rnPat pats `thenRn` \ patslist -> - returnRn (ConPatIn con' patslist) - -rnPat (ConOpPatIn pat1 con pat2) - = rnOpPat pat1 con pat2 + = 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 -> lookupFixity 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 @@ -89,31 +119,40 @@ rnPat (ConOpPatIn pat1 con pat2) rnPat neg@(NegPatIn pat) = checkRn (valid_neg_pat pat) (negPatErr neg) `thenRn_` - rnPat pat `thenRn` \ pat' -> - returnRn (NegPatIn pat') + rnPat pat `thenRn` \ (pat', fvs) -> + returnRn (NegPatIn pat', fvs) where - valid_neg_pat (LitPatIn (HsInt _)) = True - valid_neg_pat (LitPatIn (HsFrac _)) = True - valid_neg_pat _ = False + 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' -> - returnRn (ParPatIn pat') + = rnPat pat `thenRn` \ (pat', fvs) -> + returnRn (ParPatIn pat', fvs) + +rnPat (NPlusKPatIn name lit) + = litOccurrence lit `thenRn` \ fvs -> + lookupImplicitOccRn ordClass_RDR `thenRn` \ ord -> + lookupBndrRn name `thenRn` \ name' -> + returnRn (NPlusKPatIn name' lit, fvs `addOneFV` ord) rnPat (ListPatIn pats) - = addImplicitOccRn listType_name `thenRn_` - mapRn rnPat pats `thenRn` \ patslist -> - returnRn (ListPatIn patslist) + = mapFvRn rnPat pats `thenRn` \ (patslist, fvs) -> + returnRn (ListPatIn patslist, fvs `addOneFV` listTyCon_name) -rnPat (TuplePatIn pats) - = addImplicitOccRn (tupleType_name (length pats)) `thenRn_` - mapRn rnPat pats `thenRn` \ patslist -> - returnRn (TuplePatIn patslist) +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) - = lookupRn con `thenRn` \ con' -> - rnRpats rpats `thenRn` \ rpats' -> - returnRn (RecPatIn con' rpats') + = lookupOccRn con `thenRn` \ con' -> + rnRpats rpats `thenRn` \ (rpats', fvs) -> + returnRn (RecPatIn con' rpats', fvs `addOneFV` con') \end{code} ************************************************************************ @@ -123,52 +162,83 @@ rnPat (RecPatIn con rpats) ************************************************************************ \begin{code} -rnMatch :: RdrNameMatch -> RnMS s (RenamedMatch, FreeVars) +rnMatch :: RdrNameMatch -> RnMS (RenamedMatch, FreeVars) -rnMatch (PatMatch pat match) - = bindLocalsRn "pattern" binders $ \ new_binders -> - rnPat pat `thenRn` \ pat' -> - rnMatch match `thenRn` \ (match', fvMatch) -> - returnRn (PatMatch pat' match', fvMatch `minusNameSet` mkNameSet new_binders) - where - binders = collectPatBinders pat +rnMatch match@(Match _ pats maybe_rhs_sig grhss) + = pushSrcLocRn (getMatchLoc match) $ + + -- 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 -> extractHsTyRdrNames ty + tyvars_in_pats = extractPatsTyVars pats + forall_tyvars = filter (not . (`elemFM` name_env)) tyvars_in_sigs + doc = text "a pattern type-signature" + in + bindTyVarsFVRn doc (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 (collectPatsBinders pats) $ \ new_binders -> + + mapFvRn rnPat pats `thenRn` \ (pats', pat_fvs) -> + rnGRHSs grhss `thenRn` \ (grhss', grhss_fvs) -> + (case maybe_rhs_sig of + Nothing -> returnRn (Nothing, emptyFVs) + Just ty | opt_GlasgowExts -> rnHsType doc ty `thenRn` \ (ty', ty_fvs) -> + returnRn (Just ty', ty_fvs) + | otherwise -> addErrRn (patSigErr ty) `thenRn_` + returnRn (Nothing, emptyFVs) + ) `thenRn` \ (maybe_rhs_sig', ty_fvs) -> -rnMatch (GRHSMatch grhss_and_binds) - = rnGRHSsAndBinds grhss_and_binds `thenRn` \ (grhss_and_binds', fvs) -> - returnRn (GRHSMatch grhss_and_binds', 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 \end{code} %************************************************************************ %* * -\subsubsection{Guarded right-hand sides (GRHSsAndBinds)} +\subsubsection{Guarded right-hand sides (GRHSs)} %* * %************************************************************************ \begin{code} -rnGRHSsAndBinds :: RdrNameGRHSsAndBinds -> RnMS s (RenamedGRHSsAndBinds, FreeVars) - -rnGRHSsAndBinds (GRHSsAndBindsIn grhss binds) - = rnBinds binds $ \ binds' -> - rnGRHSs grhss `thenRn` \ (grhss', fvGRHS) -> - returnRn (GRHSsAndBindsIn grhss' binds', fvGRHS) +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) where - rnGRHSs [] = returnRn ([], emptyNameSet) - - rnGRHSs (grhs:grhss) - = rnGRHS grhs `thenRn` \ (grhs', fvs) -> - rnGRHSs grhss `thenRn` \ (grhss', fvss) -> - returnRn (grhs' : grhss', fvs `unionNameSets` fvss) - - rnGRHS (GRHS guard expr locn) - = pushSrcLocRn locn $ - rnExpr guard `thenRn` \ (guard', fvsg) -> - rnExpr expr `thenRn` \ (expr', fvse) -> - returnRn (GRHS guard' expr' locn, fvsg `unionNameSets` fvse) - - rnGRHS (OtherwiseGRHS expr locn) - = pushSrcLocRn locn $ - rnExpr expr `thenRn` \ (expr', fvs) -> - returnRn (OtherwiseGRHS expr' locn, fvs) + -- 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 \end{code} %************************************************************************ @@ -178,35 +248,47 @@ rnGRHSsAndBinds (GRHSsAndBindsIn grhss binds) %************************************************************************ \begin{code} -rnExprs :: [RdrNameHsExpr] -> RnMS s ([RenamedHsExpr], FreeVars) +rnExprs :: [RdrNameHsExpr] -> RnMS ([RenamedHsExpr], FreeVars) +rnExprs ls = rnExprs' ls emptyUniqSet + where + rnExprs' [] acc = returnRn ([], acc) + rnExprs' (expr:exprs) acc + = rnExpr expr `thenRn` \ (expr', fvExpr) -> -rnExprs [] = returnRn ([], emptyNameSet) + -- 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) -rnExprs (expr:exprs) - = rnExpr expr `thenRn` \ (expr', fvExpr) -> - rnExprs exprs `thenRn` \ (exprs', fvExprs) -> - returnRn (expr':exprs', fvExpr `unionNameSets` 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 + | otherwise = result \end{code} -Variables. We look up the variable and return the resulting name. The -interesting question is what the free-variable set should be. We -don't want to return imported or prelude things as free vars. So we -look at the Name returned from the lookup, and make it part of the -free-var set iff if it's a LocallyDefined Name. -\end{itemize} +Variables. We look up the variable and return the resulting name. \begin{code} -rnExpr :: RdrNameHsExpr -> RnMS s (RenamedHsExpr, FreeVars) +rnExpr :: RdrNameHsExpr -> RnMS (RenamedHsExpr, FreeVars) rnExpr (HsVar v) - = lookupOccRn v `thenRn` \ vname -> - returnRn (HsVar vname, if isLocallyDefined vname - then unitNameSet vname - else emptyUniqSet) + = lookupOccRn v `thenRn` \ name -> + if nameUnique name == assertIdKey then + -- We expand it to (GHCerr.assert__ location) + mkAssertExpr + else + -- The normal case + returnRn (HsVar name, unitFV name) + +rnExpr (HsIPVar v) + = getIPName v `thenRn` \ name -> + returnRn (HsIPVar name, emptyFVs) rnExpr (HsLit lit) - = litOccurrence lit `thenRn_` - returnRn (HsLit lit, emptyNameSet) + = litOccurrence lit `thenRn` \ fvs -> + returnRn (HsLit lit, fvs) rnExpr (HsLam match) = rnMatch match `thenRn` \ (match', fvMatch) -> @@ -215,94 +297,133 @@ rnExpr (HsLam match) rnExpr (HsApp fun arg) = rnExpr fun `thenRn` \ (fun',fvFun) -> rnExpr arg `thenRn` \ (arg',fvArg) -> - returnRn (HsApp fun' arg', fvFun `unionNameSets` fvArg) - -rnExpr (OpApp e1 (HsVar op) e2) = rnOpApp e1 op e2 - -rnExpr (NegApp e n) = completeNegApp (rnExpr e) + returnRn (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) -> + + -- 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 -> lookupFixity op_name `thenRn` \ fixity -> + mkOpAppRn e1' op' fixity e2' + InterfaceMode -> returnRn (OpApp e1' op' defaultFixity e2') + ) `thenRn` \ final_e -> + + returnRn (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) -> + lookupImplicitOccRn negate_RDR `thenRn` \ neg -> + mkNegAppRn e' (HsVar neg) `thenRn` \ final_e -> + returnRn (final_e, fv_e `addOneFV` neg) rnExpr (HsPar e) = rnExpr e `thenRn` \ (e', fvs_e) -> returnRn (HsPar e', fvs_e) -rnExpr (SectionL expr op) - = rnExpr expr `thenRn` \ (expr', fvs_expr) -> - rnExpr op `thenRn` \ (op', fvs_op) -> - returnRn (SectionL expr' op', fvs_op `unionNameSets` fvs_expr) +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 (SectionR op expr) - = rnExpr op `thenRn` \ (op', fvs_op) -> - rnExpr expr `thenRn` \ (expr', fvs_expr) -> - returnRn (SectionR op' expr', fvs_op `unionNameSets` 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 (CCall fun args may_gc is_casm fake_result_ty) - = lookupImplicitOccRn ccallableClass_RDR `thenRn_` - lookupImplicitOccRn creturnableClass_RDR `thenRn_` + -- Check out the comment on RnIfaces.getNonWiredDataDecl about ccalls + = lookupImplicitOccRn ccallableClass_RDR `thenRn` \ cc -> + lookupImplicitOccRn creturnableClass_RDR `thenRn` \ cr -> + lookupImplicitOccRn ioDataCon_RDR `thenRn` \ io -> rnExprs args `thenRn` \ (args', fvs_args) -> - returnRn (CCall fun args' may_gc is_casm fake_result_ty, fvs_args) + returnRn (CCall fun args' may_gc is_casm fake_result_ty, + fvs_args `addOneFV` cc `addOneFV` cr `addOneFV` io) -rnExpr (HsSCC label expr) +rnExpr (HsSCC lbl expr) = rnExpr expr `thenRn` \ (expr', fvs_expr) -> - returnRn (HsSCC label expr', fvs_expr) + returnRn (HsSCC lbl expr', fvs_expr) rnExpr (HsCase expr ms src_loc) = pushSrcLocRn src_loc $ rnExpr expr `thenRn` \ (new_expr, e_fvs) -> - mapAndUnzipRn rnMatch ms `thenRn` \ (new_ms, ms_fvs) -> - returnRn (HsCase new_expr new_ms src_loc, unionManyNameSets (e_fvs : ms_fvs)) + mapFvRn rnMatch ms `thenRn` \ (new_ms, ms_fvs) -> + returnRn (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 (HsDo stmts src_loc) - = pushSrcLocRn src_loc $ - lookupImplicitOccRn monadZeroClass_RDR `thenRn_` -- Forces Monad to come too - rnStmts stmts `thenRn` \ (stmts', fvStmts) -> - returnRn (HsDo stmts' src_loc, fvStmts) +rnExpr (HsWith expr binds) + = rnExpr expr `thenRn` \ (expr',fvExpr) -> + rnIPBinds binds `thenRn` \ (binds',fvBinds) -> + returnRn (HsWith expr' binds', fvExpr `plusFV` fvBinds) -rnExpr (ListComp expr quals) - = addImplicitOccRn listType_name `thenRn_` - rnQuals expr quals `thenRn` \ ((expr', quals'), fvs) -> - returnRn (ListComp expr' quals', fvs) +rnExpr e@(HsDo do_or_lc stmts src_loc) + = pushSrcLocRn src_loc $ + lookupImplicitOccRn monadClass_RDR `thenRn` \ monad -> + 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 `addOneFV` monad) rnExpr (ExplicitList exps) - = addImplicitOccRn listType_name `thenRn_` - rnExprs exps `thenRn` \ (exps', fvs) -> - returnRn (ExplicitList exps', fvs) + = rnExprs exps `thenRn` \ (exps', fvs) -> + returnRn (ExplicitList exps', fvs `addOneFV` listTyCon_name) -rnExpr (ExplicitTuple exps) - = addImplicitOccRn (tupleType_name (length exps)) `thenRn_` - rnExprs exps `thenRn` \ (exps', fvExps) -> - returnRn (ExplicitTuple exps', fvExps) +rnExpr (ExplicitTuple exps boxed) + = rnExprs exps `thenRn` \ (exps', fvs) -> + returnRn (ExplicitTuple exps' boxed, fvs `addOneFV` tycon_name) + where + tycon_name = tupleTyCon_name boxed (length exps) -rnExpr (RecordCon (HsVar con) rbinds) - = lookupOccRn con `thenRn` \ conname -> +rnExpr (RecordCon con_id rbinds) + = lookupOccRn con_id `thenRn` \ conname -> rnRbinds "construction" rbinds `thenRn` \ (rbinds', fvRbinds) -> - returnRn (RecordCon (HsVar conname) rbinds', fvRbinds) + returnRn (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 `unionNameSets` fvRbinds) + returnRn (RecordUpd expr' rbinds', fvExpr `plusFV` fvRbinds) rnExpr (ExprWithTySig expr pty) - = rnExpr expr `thenRn` \ (expr', fvExpr) -> - rnHsType pty `thenRn` \ pty' -> - returnRn (ExprWithTySig expr' pty', fvExpr) + = rnExpr expr `thenRn` \ (expr', fvExpr) -> + rnHsSigType (text "an expression") pty `thenRn` \ (pty', fvTy) -> + returnRn (ExprWithTySig expr' pty', fvExpr `plusFV` fvTy) 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, unionManyNameSets [fvP, fvB1, fvB2]) + returnRn (HsIf p' b1' b2' src_loc, plusFVs [fvP, fvB1, fvB2]) rnExpr (ArithSeqIn seq) - = lookupImplicitOccRn enumClass_RDR `thenRn_` + = lookupImplicitOccRn enumClass_RDR `thenRn` \ enum -> rn_seq seq `thenRn` \ (new_seq, fvs) -> - returnRn (ArithSeqIn new_seq, fvs) + returnRn (ArithSeqIn new_seq, fvs `addOneFV` enum) where rn_seq (From expr) = rnExpr expr `thenRn` \ (expr', fvExpr) -> @@ -311,19 +432,34 @@ rnExpr (ArithSeqIn seq) rn_seq (FromThen expr1 expr2) = rnExpr expr1 `thenRn` \ (expr1', fvExpr1) -> rnExpr expr2 `thenRn` \ (expr2', fvExpr2) -> - returnRn (FromThen expr1' expr2', fvExpr1 `unionNameSets` 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 `unionNameSets` 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', - unionManyNameSets [fvExpr1, fvExpr2, fvExpr3]) + plusFVs [fvExpr1, fvExpr2, fvExpr3]) +\end{code} + +These three are pattern syntax appearing in expressions. +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) \end{code} %************************************************************************ @@ -334,129 +470,113 @@ rnExpr (ArithSeqIn seq) \begin{code} rnRbinds str rbinds - = mapRn field_dup_err dup_fields `thenRn_` - mapAndUnzipRn rn_rbind rbinds `thenRn` \ (rbinds', fvRbind_s) -> - returnRn (rbinds', unionManyNameSets fvRbind_s) + = mapRn_ field_dup_err dup_fields `thenRn_` + mapFvRn rn_rbind rbinds `thenRn` \ (rbinds', fvRbind) -> + returnRn (rbinds', fvRbind) where - (_, dup_fields) = removeDups cmp [ f | (f,_,_) <- rbinds ] + (_, dup_fields) = removeDups compare [ f | (f,_,_) <- rbinds ] field_dup_err dups = addErrRn (dupFieldErr str dups) rn_rbind (field, expr, pun) - = lookupOccRn field `thenRn` \ fieldname -> + = lookupGlobalOccRn field `thenRn` \ fieldname -> rnExpr expr `thenRn` \ (expr', fvExpr) -> - returnRn ((fieldname, expr', pun), fvExpr) + returnRn ((fieldname, expr', pun), fvExpr `addOneFV` fieldname) rnRpats rpats - = mapRn field_dup_err dup_fields `thenRn_` - mapRn rn_rpat rpats + = mapRn_ field_dup_err dup_fields `thenRn_` + mapFvRn rn_rpat rpats `thenRn` \ (rpats', fvs) -> + returnRn (rpats', fvs) where - (_, dup_fields) = removeDups cmp [ f | (f,_,_) <- rpats ] + (_, dup_fields) = removeDups compare [ f | (f,_,_) <- rpats ] field_dup_err dups = addErrRn (dupFieldErr "pattern" dups) rn_rpat (field, pat, pun) - = lookupOccRn field `thenRn` \ fieldname -> - rnPat pat `thenRn` \ pat' -> - returnRn (fieldname, pat', pun) + = lookupGlobalOccRn field `thenRn` \ fieldname -> + rnPat pat `thenRn` \ (pat', fvs) -> + returnRn ((fieldname, pat', pun), fvs `addOneFV` fieldname) \end{code} %************************************************************************ %* * -\subsubsection{@Qualifier@s: in list comprehensions} +\subsubsection{@rnIPBinds@s: in implicit parameter bindings} * %* * %************************************************************************ -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} -rnQuals :: RdrNameHsExpr -> [RdrNameQual] - -> RnMS s ((RenamedHsExpr, [RenamedQual]), FreeVars) - -rnQuals expr [qual] -- must be at least one qual - = rnQual qual $ \ new_qual -> - rnExpr expr `thenRn` \ (expr', fvs) -> - returnRn ((expr', [new_qual]), fvs) - -rnQuals expr (qual: quals) - = rnQual qual $ \ qual' -> - rnQuals expr quals `thenRn` \ ((expr', quals'), fv_quals) -> - returnRn ((expr', qual' : quals'), fv_quals) - - --- rnQual :: RdrNameQual --- -> (RenamedQual -> RnMS s (a,FreeVars)) --- -> RnMS s (a,FreeVars) --- Because of mutual recursion the actual type is a bit less general than this [Haskell 1.2] - -rnQual (GeneratorQual pat expr) thing_inside - = rnExpr expr `thenRn` \ (expr', fv_expr) -> - bindLocalsRn "pattern in list comprehension" binders $ \ new_binders -> - rnPat pat `thenRn` \ pat' -> - - thing_inside (GeneratorQual pat' expr') `thenRn` \ (result, fvs) -> - returnRn (result, fv_expr `unionNameSets` (fvs `minusNameSet` mkNameSet new_binders)) - where - binders = collectPatBinders pat +rnIPBinds [] = returnRn ([], emptyFVs) +rnIPBinds ((n, expr) : binds) + = getIPName n `thenRn` \ name -> + rnExpr expr `thenRn` \ (expr',fvExpr) -> + rnIPBinds binds `thenRn` \ (binds',fvBinds) -> + returnRn ((name, expr') : binds', fvExpr `plusFV` fvBinds) -rnQual (FilterQual expr) thing_inside - = rnExpr expr `thenRn` \ (expr', fv_expr) -> - thing_inside (FilterQual expr') `thenRn` \ (result, fvs) -> - returnRn (result, fv_expr `unionNameSets` fvs) - -rnQual (LetQual binds) thing_inside - = rnBinds binds $ \ binds' -> - thing_inside (LetQual binds') \end{code} - %************************************************************************ %* * \subsubsection{@Stmt@s: in @do@ expressions} %* * %************************************************************************ +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 :: [RdrNameStmt] -> RnMS s ([RenamedStmt], FreeVars) +type RnExprTy = RdrNameHsExpr -> RnMS (RenamedHsExpr, FreeVars) -rnStmts [stmt@(ExprStmt expr src_loc)] -- last stmt must be ExprStmt - = pushSrcLocRn src_loc $ - rnExpr expr `thenRn` \ (expr', fv_expr) -> - returnRn ([ExprStmt expr' src_loc], fv_expr) +rnStmts :: RnExprTy + -> [RdrNameStmt] + -> RnMS ([RenamedStmt], FreeVars) -rnStmts (stmt:stmts) - = rnStmt stmt $ \ stmt' -> - rnStmts stmts `thenRn` \ (stmts', fv_stmts) -> - returnRn (stmt':stmts', fv_stmts) +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 :: RdrNameStmt -> (RenamedStmt -> RnMS s (a, FreeVars)) -> RnMS s (a, FreeVars) --- Because of mutual recursion the actual type is a bit less general than this [Haskell 1.2] +rnStmt :: RnExprTy -> RdrNameStmt + -> (RenamedStmt -> RnMS (a, FreeVars)) + -> RnMS (a, FreeVars) +-- Because of mutual recursion we have to pass in rnExpr. -rnStmt (BindStmt pat expr src_loc) thing_inside +rnStmt rn_expr (BindStmt pat expr src_loc) thing_inside = pushSrcLocRn src_loc $ - rnExpr expr `thenRn` \ (expr', fv_expr) -> - bindLocalsRn "pattern in do binding" binders $ \ new_binders -> - rnPat pat `thenRn` \ pat' -> - + 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 `unionNameSets` (fvs `minusNameSet` mkNameSet new_binders)) + returnRn (result, fv_expr `plusFV` fvs `plusFV` fv_pat) where binders = collectPatBinders pat + doc = text "a pattern in do binding" -rnStmt (ExprStmt expr src_loc) thing_inside +rnStmt rn_expr (ExprStmt expr src_loc) thing_inside = pushSrcLocRn src_loc $ - rnExpr expr `thenRn` \ (expr', fv_expr) -> + rn_expr expr `thenRn` \ (expr', fv_expr) -> thing_inside (ExprStmt expr' src_loc) `thenRn` \ (result, fvs) -> - returnRn (result, fv_expr `unionNameSets` 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 (LetStmt binds) thing_inside +rnStmt rn_expr (LetStmt binds) thing_inside = rnBinds binds $ \ binds' -> thing_inside (LetStmt binds') \end{code} @@ -467,99 +587,140 @@ rnStmt (LetStmt binds) thing_inside %* * %************************************************************************ -@rnOpApp@ deals with operator applications. It does some rearrangement of -the expression so that the precedences are right. This must be done on the -expression *before* renaming, because fixity info applies to the things -the programmer actually wrote. +@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} -rnOpApp (NegApp e11 n) op e2 - = lookupFixity op `thenRn` \ (Fixity op_prec op_dir) -> - if op_prec > 6 then - -- negate precedence 6 wired in - -- (-x)*y ==> -(x*y) - completeNegApp (rnOpApp e11 op e2) - else - completeOpApp (completeNegApp (rnExpr e11)) op (rnExpr e2) - -rnOpApp (OpApp e11 (HsVar op1) e12) op e2 - = lookupFixity op `thenRn` \ op_fix@(Fixity op_prec op_dir) -> - lookupFixity op1 `thenRn` \ op1_fix@(Fixity op1_prec op1_dir) -> - -- pprTrace "rnOpApp:" (ppCat [ppr PprDebug op, ppInt op_prec, ppr PprDebug op1, ppInt op1_prec]) $ - case (op1_prec `cmp` op_prec) of - LT_ -> rearrange - EQ_ -> case (op1_dir, op_dir) of - (InfixR, InfixR) -> rearrange - (InfixL, InfixL) -> dont_rearrange - _ -> addErrRn (precParseErr (op1,op1_fix) (op,op_fix)) `thenRn_` - dont_rearrange - GT__ -> dont_rearrange +mkOpAppRn :: RenamedHsExpr -- Left operand; already rearranged + -> RenamedHsExpr -> Fixity -- Operator and fixity + -> RenamedHsExpr -- Right operand (not an OpApp, but might + -- be a NegApp) + -> RnMS 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) + + | associate_right + = mkOpAppRn e12 op2 fix2 e2 `thenRn` \ new_e -> + returnRn (OpApp e11 op1 fix1 new_e) where - rearrange = rnOpApp e11 op1 (OpApp e12 (HsVar op) e2) - dont_rearrange = completeOpApp (rnOpApp e11 op1 e12) op (rnExpr e2) - -rnOpApp e1 op e2 = completeOpApp (rnExpr e1) op (rnExpr e2) - -completeOpApp rn_e1 op rn_e2 - = rn_e1 `thenRn` \ (e1', fvs1) -> - rn_e2 `thenRn` \ (e2', fvs2) -> - rnExpr (HsVar op) `thenRn` \ (op', fvs3) -> - returnRn (OpApp e1' op' e2', fvs1 `unionNameSets` fvs2 `unionNameSets` fvs3) - -completeNegApp rn_expr - = rn_expr `thenRn` \ (e', fvs_e) -> - lookupImplicitOccRn negate_RDR `thenRn` \ neg -> - returnRn (NegApp e' (HsVar neg), fvs_e) + (nofix_error, associate_right) = compareFixity fix1 fix2 + +--------------------------- +-- (- neg_arg) `op` e2 +mkOpAppRn e1@(NegApp neg_arg neg_op) op2 fix2 e2 + | nofix_error + = addErrRn (precParseErr (pp_prefix_minus,negateFixity) (ppr_op op2,fix2)) `thenRn_` + returnRn (OpApp e1 op2 fix2 e2) + + | associate_right + = mkOpAppRn neg_arg op2 fix2 e2 `thenRn` \ new_e -> + returnRn (NegApp new_e neg_op) + 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) + where + (nofix_err, 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 + ) + returnRn (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_op + = +#ifdef DEBUG + getModeRn `thenRn` \ mode -> + ASSERT( not_op_app mode neg_arg ) +#endif + returnRn (NegApp neg_arg neg_op) + +not_op_app SourceMode (OpApp _ _ _ _) = False +not_op_app mode other = True \end{code} \begin{code} -rnOpPat p1@(NegPatIn p11) op p2 - = lookupFixity op `thenRn` \ op_fix@(Fixity op_prec op_dir) -> - if op_prec > 6 then - -- negate precedence 6 wired in - addErrRn (precParseNegPatErr (op,op_fix)) `thenRn_` - rnOpPat p11 op p2 `thenRn` \ op_pat -> - returnRn (NegPatIn op_pat) - else - completeOpPat (rnPat p1) op (rnPat p2) - -rnOpPat (ConOpPatIn p11 op1 p12) op p2 - = lookupFixity op `thenRn` \ op_fix@(Fixity op_prec op_dir) -> - lookupFixity op1 `thenRn` \ op1_fix@(Fixity op1_prec op1_dir) -> - case (op1_prec `cmp` op_prec) of - LT_ -> rearrange - EQ_ -> case (op1_dir, op_dir) of - (InfixR, InfixR) -> rearrange - (InfixL, InfixL) -> dont_rearrange - _ -> addErrRn (precParseErr (op1,op1_fix) (op,op_fix)) `thenRn_` - dont_rearrange - GT__ -> dont_rearrange - where - rearrange = rnOpPat p11 op1 (ConOpPatIn p12 op p2) - dont_rearrange = completeOpPat (rnOpPat p11 op1 p12) op (rnPat p2) +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) -rnOpPat p1 op p2 = completeOpPat (rnPat p1) op (rnPat p2) + | associate_right + = mkConOpPatRn p12 op2 fix2 p2 `thenRn` \ new_p -> + returnRn (ConOpPatIn p11 op1 fix1 new_p) -completeOpPat rn_p1 op rn_p2 - = rn_p1 `thenRn` \ p1' -> - rn_p2 `thenRn` \ p2' -> - lookupRn op `thenRn` \ op' -> - returnRn (ConOpPatIn p1' op' p2') + 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 -> RdrName -> RdrNameMatch -> RnMS s () +checkPrecMatch :: Bool -> Name -> RenamedMatch -> RnMS () checkPrecMatch False fn match = returnRn () -checkPrecMatch True op (PatMatch p1 (PatMatch p2 (GRHSMatch _))) - = checkPrec op p1 False `thenRn_` - checkPrec op p2 True -checkPrecMatch True op _ - = panic "checkPrecMatch" -checkPrec op (ConOpPatIn _ op1 _) right +checkPrecMatch True op (Match _ (p1:p2:_) _ _) + -- True indicates an infix lhs + = getModeRn `thenRn` \ mode -> + -- See comments with rnExpr (OpApp ...) + case mode of + InterfaceMode -> returnRn () + SourceMode -> checkPrec op p1 False `thenRn_` + checkPrec op p2 True + +checkPrecMatch True op _ = panic "checkPrecMatch" + +checkPrec op (ConOpPatIn _ op1 _ _) right = lookupFixity op `thenRn` \ op_fix@(Fixity op_prec op_dir) -> lookupFixity op1 `thenRn` \ op1_fix@(Fixity op1_prec op1_dir) -> let @@ -568,18 +729,58 @@ checkPrec op (ConOpPatIn _ op1 _) right (op1_dir == InfixR && op_dir == InfixR && right || op1_dir == InfixL && op_dir == InfixL && not right)) - info = (op,op_fix) - info1 = (op1,op1_fix) + info = (ppr_op op, op_fix) + 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 = lookupFixity op `thenRn` \ op_fix@(Fixity op_prec op_dir) -> - checkRn (op_prec <= 6) (precParseNegPatErr (op,op_fix)) + checkRn (op_prec <= negatePrecedence) (precParseNegPatErr (ppr_op op,op_fix)) checkPrec op pat right = returnRn () + +-- 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 + = case arg of + OpApp _ op fix _ -> go_for_it (ppr_op op) fix + NegApp _ op -> go_for_it pp_prefix_minus negateFixity + other -> returnRn () + where + HsVar op_name = op + go_for_it pp_arg_op arg_fix@(Fixity arg_prec _) + = lookupFixity 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) +\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} %************************************************************************ @@ -588,67 +789,139 @@ checkPrec op pat right %* * %************************************************************************ -When literals occur we have to make sure that the types and classes they involve +When literals occur we have to make sure +that the types and classes they involve are made available. \begin{code} litOccurrence (HsChar _) - = addImplicitOccRn charType_name + = returnRn (unitFV charTyCon_name) litOccurrence (HsCharPrim _) - = addImplicitOccRn (getName charPrimTyCon) + = returnRn (unitFV (getName charPrimTyCon)) litOccurrence (HsString _) - = addImplicitOccRn listType_name `thenRn_` - addImplicitOccRn charType_name + = returnRn (unitFV listTyCon_name `plusFV` unitFV charTyCon_name) litOccurrence (HsStringPrim _) - = addImplicitOccRn (getName addrPrimTyCon) + = returnRn (unitFV (getName addrPrimTyCon)) litOccurrence (HsInt _) - = lookupImplicitOccRn numClass_RDR `thenRn_` -- Int and Integer are forced in by Num - returnRn () + = lookupImplicitOccRn numClass_RDR `thenRn` \ num -> + returnRn (unitFV num) -- Int and Integer are forced in by Num litOccurrence (HsFrac _) - = lookupImplicitOccRn fractionalClass_RDR `thenRn_` -- ... similarly Rational - returnRn () - + = lookupImplicitOccRn fractionalClass_RDR `thenRn` \ frac -> + lookupImplicitOccRn ratioDataCon_RDR `thenRn` \ ratio -> + returnRn (unitFV frac `plusFV` unitFV ratio) + -- 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 _) - = addImplicitOccRn (getName intPrimTyCon) + = returnRn (unitFV (getName intPrimTyCon)) litOccurrence (HsFloatPrim _) - = addImplicitOccRn (getName floatPrimTyCon) + = returnRn (unitFV (getName floatPrimTyCon)) litOccurrence (HsDoublePrim _) - = addImplicitOccRn (getName doublePrimTyCon) + = returnRn (unitFV (getName doublePrimTyCon)) litOccurrence (HsLitLit _) - = lookupImplicitOccRn ccallableClass_RDR `thenRn_` - returnRn () + = lookupImplicitOccRn ccallableClass_RDR `thenRn` \ cc -> + returnRn (unitFV cc) \end{code} - %************************************************************************ %* * -\subsubsection{Errors} +\subsubsection{Assertion utils} %* * %************************************************************************ \begin{code} -dupFieldErr str (dup:rest) sty - = ppBesides [ppStr "duplicate field name `", ppr sty dup, ppStr "' in record ", ppStr str] +mkAssertExpr :: RnMS (RenamedHsExpr, FreeVars) +mkAssertExpr = + mkImportedGlobalFromRdrName assertErr_RDR `thenRn` \ name -> + getSrcLocRn `thenRn` \ sloc -> -negPatErr pat sty - = ppSep [ppStr "prefix `-' not applied to literal in pattern", ppr sty pat] + -- if we're ignoring asserts, return (\ _ e -> e) + -- if not, return (assertError "src-loc") -precParseNegPatErr op sty - = ppHang (ppStr "precedence parsing error") - 4 (ppBesides [ppStr "prefix `-' has lower precedence than ", pp_op sty op, ppStr " in pattern"]) + 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 + let + expr = + HsApp (HsVar name) + (HsLit (HsString (_PK_ (showSDoc (ppr sloc))))) -precParseErr op1 op2 sty - = ppHang (ppStr "precedence parsing error") - 4 (ppBesides [ppStr "cannot mix ", pp_op sty op1, ppStr " and ", pp_op sty op2, - ppStr " in the same infix expression"]) + in + returnRn (expr, unitFV name) -pp_op sty (op, fix) = ppBesides [pprSym sty op, ppLparen, ppr sty fix, ppRparen] +\end{code} + +%************************************************************************ +%* * +\subsubsection{Errors} +%* * +%************************************************************************ + +\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:"), + nest 4 (ppr e)] \end{code}