X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Frename%2FRnExpr.lhs;h=87ac92ddc38d952cd1ba54f4aab0231d103ad6af;hb=d0f325ce37d6ee322168e44392f10e0ed52f8294;hp=9c7a1f5970cea217392a7ca29a5d5bf7fece61d1;hpb=f0e42a460a3bb4857f3c4bfa92dd134fcf409849;p=ghc-hetmet.git diff --git a/ghc/compiler/rename/RnExpr.lhs b/ghc/compiler/rename/RnExpr.lhs index 9c7a1f5..87ac92d 100644 --- a/ghc/compiler/rename/RnExpr.lhs +++ b/ghc/compiler/rename/RnExpr.lhs @@ -5,34 +5,43 @@ Basically dependency analysis. -Handles @Match@, @GRHSsAndBinds@, @HsExpr@, and @Qual@ datatypes. In +Handles @Match@, @GRHSsAndBinds@, @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, checkPrecMatch ) where -import Ubiq -import RnLoop -- break the RnPass/RnExpr/RnBinds loops +#include "HsVersions.h" + +import {-# SOURCE #-} RnBinds +import {-# SOURCE #-} RnSource ( rnHsSigType ) import HsSyn import RdrHsSyn import RnHsSyn import RnMonad - -import ErrUtils ( addErrLoc ) -import Name ( isLocallyDefinedName, pprOp, Name, RdrName ) -import Pretty -import UniqFM ( lookupUFM ) -import UniqSet ( emptyUniqSet, unitUniqSet, - unionUniqSets, unionManyUniqSets, - UniqSet(..) ) -import Util ( Ord3(..), panic ) +import RnEnv +import CmdLineOpts ( opt_GlasgowExts ) +import BasicTypes ( Fixity(..), FixityDirection(..), IfaceFlavour(..) ) +import PrelInfo ( numClass_RDR, fractionalClass_RDR, eqClass_RDR, + ccallableClass_RDR, creturnableClass_RDR, + monadZeroClass_RDR, enumClass_RDR, ordClass_RDR, + ratioDataCon_RDR, negate_RDR, assertErr_RDR, + ioDataCon_RDR, ioOkDataCon_RDR + ) +import TysPrim ( charPrimTyCon, addrPrimTyCon, intPrimTyCon, + floatPrimTyCon, doublePrimTyCon + ) +import Name +import UniqFM ( isNullUFM ) +import UniqSet ( emptyUniqSet, unionManyUniqSets, UniqSet ) +import Unique ( assertIdKey ) +import Util ( removeDups ) +import Outputable \end{code} @@ -43,39 +52,46 @@ import Util ( Ord3(..), panic ) ********************************************************* \begin{code} -rnPat :: RdrNamePat -> RnM_Fixes s RenamedPat +rnPat :: RdrNamePat -> RnMS s RenamedPat rnPat WildPatIn = returnRn WildPatIn rnPat (VarPatIn name) - = lookupValue name `thenRn` \ vname -> + = lookupBndrRn name `thenRn` \ vname -> returnRn (VarPatIn vname) -rnPat (LitPatIn n) = returnRn (LitPatIn n) +rnPat (LitPatIn lit) + = litOccurrence lit `thenRn_` + lookupImplicitOccRn eqClass_RDR `thenRn_` -- Needed to find equality on pattern + returnRn (LitPatIn lit) rnPat (LazyPatIn pat) = rnPat pat `thenRn` \ pat' -> returnRn (LazyPatIn pat') rnPat (AsPatIn name pat) - = rnPat pat `thenRn` \ pat' -> - lookupValue name `thenRn` \ vname -> + = rnPat pat `thenRn` \ pat' -> + lookupBndrRn name `thenRn` \ vname -> returnRn (AsPatIn vname pat') -rnPat (ConPatIn name pats) - = lookupValue name `thenRn` \ name' -> +rnPat (ConPatIn con pats) + = lookupOccRn con `thenRn` \ con' -> mapRn rnPat pats `thenRn` \ patslist -> - returnRn (ConPatIn name' patslist) + returnRn (ConPatIn con' patslist) -rnPat (ConOpPatIn pat1 name pat2) - = lookupValue name `thenRn` \ name' -> - rnPat pat1 `thenRn` \ pat1' -> +rnPat (ConOpPatIn pat1 con _ pat2) + = rnPat pat1 `thenRn` \ pat1' -> + lookupOccRn con `thenRn` \ con' -> + lookupFixity con `thenRn` \ fixity -> rnPat pat2 `thenRn` \ pat2' -> - precParsePat (ConOpPatIn pat1' name' pat2') + mkConOpPatRn pat1' con' fixity pat2' +-- Negated patters can only be literals, and they are dealt with +-- by negating the literal at compile time, not by using the negation +-- operation in Num. So we don't need to make an implicit reference +-- to negate_RDR. rnPat neg@(NegPatIn pat) - = getSrcLocRn `thenRn` \ src_loc -> - addErrIfRn (not (valid_neg_pat pat)) (negPatErr neg src_loc) + = checkRn (valid_neg_pat pat) (negPatErr neg) `thenRn_` rnPat pat `thenRn` \ pat' -> returnRn (NegPatIn pat') @@ -88,17 +104,26 @@ rnPat (ParPatIn pat) = rnPat pat `thenRn` \ pat' -> returnRn (ParPatIn pat') +rnPat (NPlusKPatIn name lit) + = litOccurrence lit `thenRn_` + lookupImplicitOccRn ordClass_RDR `thenRn_` + lookupBndrRn name `thenRn` \ name' -> + returnRn (NPlusKPatIn name' lit) + rnPat (ListPatIn pats) - = mapRn rnPat pats `thenRn` \ patslist -> + = addImplicitOccRn listType_name `thenRn_` + mapRn rnPat pats `thenRn` \ patslist -> returnRn (ListPatIn patslist) rnPat (TuplePatIn pats) - = mapRn rnPat pats `thenRn` \ patslist -> + = addImplicitOccRn (tupleType_name (length pats)) `thenRn_` + mapRn rnPat pats `thenRn` \ patslist -> returnRn (TuplePatIn patslist) rnPat (RecPatIn con rpats) - = panic "rnPat:RecPatIn" - + = lookupOccRn con `thenRn` \ con' -> + rnRpats rpats `thenRn` \ rpats' -> + returnRn (RecPatIn con' rpats') \end{code} ************************************************************************ @@ -108,28 +133,35 @@ rnPat (RecPatIn con rpats) ************************************************************************ \begin{code} -rnMatch :: RdrNameMatch -> RnM_Fixes s (RenamedMatch, FreeVars) - -rnMatch match - = getSrcLocRn `thenRn` \ src_loc -> - newLocalNames "variable in pattern" - (binders `zip` repeat src_loc) `thenRn` \ new_binders -> - extendSS2 new_binders (rnMatch_aux match) - where - binders = collect_binders match +rnMatch, rnMatch1 :: RdrNameMatch -> RnMS s (RenamedMatch, FreeVars) - collect_binders :: RdrNameMatch -> [RdrName] - - collect_binders (GRHSMatch _) = [] - collect_binders (PatMatch pat match) - = collectPatBinders pat ++ collect_binders match - -rnMatch_aux (PatMatch pat match) - = rnPat pat `thenRn` \ pat' -> - rnMatch_aux match `thenRn` \ (match', fvMatch) -> - returnRn (PatMatch pat' match', fvMatch) +-- The only tricky bit here is that we want to do a single +-- bindLocalsRn for all the matches together, so that we spot +-- the repeated variable in +-- f x x = 1 -rnMatch_aux (GRHSMatch grhss_and_binds) +rnMatch match + = pushSrcLocRn (getMatchLoc match) $ + bindLocalsRn "pattern" (get_binders match) $ \ new_binders -> + rnMatch1 match `thenRn` \ (match', fvs) -> + let + binder_set = mkNameSet new_binders + unused_binders = binder_set `minusNameSet` fvs + net_fvs = fvs `minusNameSet` binder_set + in + warnUnusedMatches unused_binders `thenRn_` + + returnRn (match', net_fvs) + where + get_binders (GRHSMatch _) = [] + get_binders (PatMatch pat match) = collectPatBinders pat ++ get_binders match + +rnMatch1 (PatMatch pat match) + = rnPat pat `thenRn` \ pat' -> + rnMatch1 match `thenRn` \ (match', fvs) -> + returnRn (PatMatch pat' match', fvs) + +rnMatch1 (GRHSMatch grhss_and_binds) = rnGRHSsAndBinds grhss_and_binds `thenRn` \ (grhss_and_binds', fvs) -> returnRn (GRHSMatch grhss_and_binds', fvs) \end{code} @@ -141,30 +173,42 @@ rnMatch_aux (GRHSMatch grhss_and_binds) %************************************************************************ \begin{code} -rnGRHSsAndBinds :: RdrNameGRHSsAndBinds -> RnM_Fixes s (RenamedGRHSsAndBinds, FreeVars) +rnGRHSsAndBinds :: RdrNameGRHSsAndBinds -> RnMS s (RenamedGRHSsAndBinds, FreeVars) rnGRHSsAndBinds (GRHSsAndBindsIn grhss binds) - = rnBinds binds `thenRn` \ (binds', fvBinds, scope) -> - extendSS2 scope (rnGRHSs grhss) `thenRn` \ (grhss', fvGRHS) -> - returnRn (GRHSsAndBindsIn grhss' binds', fvBinds `unionUniqSets` fvGRHS) + = rnBinds binds $ \ binds' -> + rnGRHSs grhss `thenRn` \ (grhss', fvGRHS) -> + returnRn (GRHSsAndBindsIn grhss' binds', fvGRHS) where - rnGRHSs [] = returnRn ([], emptyUniqSet) + rnGRHSs [] = returnRn ([], emptyNameSet) rnGRHSs (grhs:grhss) = rnGRHS grhs `thenRn` \ (grhs', fvs) -> rnGRHSs grhss `thenRn` \ (grhss', fvss) -> - returnRn (grhs' : grhss', fvs `unionUniqSets` 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 `unionUniqSets` fvse) + (if not (opt_GlasgowExts || is_standard_guard guard) then + addWarnRn (nonStdGuardErr guard) + else + returnRn () + ) `thenRn_` - rnGRHS (OtherwiseGRHS expr locn) - = pushSrcLocRn locn $ - rnExpr expr `thenRn` \ (expr', fvs) -> - returnRn (OtherwiseGRHS expr' locn, fvs) + (rnStmts rnExpr guard $ \ guard' -> + -- This nested thing deals with scope and + -- the free vars of the guard, and knocking off the + -- free vars of the rhs that are bound by the guard + + rnExpr expr `thenRn` \ (expr', fvse) -> + returnRn (GRHS guard' expr' locn, fvse)) + + -- 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 [] = True + is_standard_guard [GuardStmt _ _] = True + is_standard_guard other = False \end{code} %************************************************************************ @@ -174,38 +218,51 @@ rnGRHSsAndBinds (GRHSsAndBindsIn grhss binds) %************************************************************************ \begin{code} -rnExprs :: [RdrNameHsExpr] -> RnM_Fixes s ([RenamedHsExpr], FreeVars) - -rnExprs [] = returnRn ([], emptyUniqSet) +rnExprs :: [RdrNameHsExpr] -> RnMS s ([RenamedHsExpr], FreeVars) +rnExprs ls = rnExprs' ls emptyUniqSet + where + rnExprs' [] acc = returnRn ([], acc) + rnExprs' (expr:exprs) acc + = rnExpr expr `thenRn` \ (expr', fvExpr) -> + + -- Now we do a "seq" on the free vars because typically it's small + -- or empty, especially in very long lists of constants + let + acc' = acc `unionNameSets` 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 `unionUniqSets` 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 RnName returned from the lookup, and make it part of the -free-var set iff if it's a LocallyDefined RnName. - -ToDo: what about RnClassOps ??? +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} \begin{code} -rnExpr :: RdrNameHsExpr -> RnM_Fixes s (RenamedHsExpr, FreeVars) +rnExpr :: RdrNameHsExpr -> RnMS s (RenamedHsExpr, FreeVars) rnExpr (HsVar v) - = lookupValue v `thenRn` \ vname -> - returnRn (HsVar vname, fv_set vname) - where - fv_set vname@(RnName n) - | isLocallyDefinedName n = unitUniqSet vname - fv_set _ = emptyUniqSet + = lookupOccRn v `thenRn` \ name -> + if nameUnique name == assertIdKey then + -- We expand it to (GHCerr.assert__ location) + mkAssertExpr `thenRn` \ expr -> + returnRn (expr, emptyUniqSet) + else + -- The normal case + returnRn (HsVar name, if isLocallyDefined name + then unitNameSet name + else emptyUniqSet) -rnExpr (HsLit lit) - = returnRn (HsLit lit, emptyUniqSet) +rnExpr (HsLit lit) + = litOccurrence lit `thenRn_` + returnRn (HsLit lit, emptyNameSet) rnExpr (HsLam match) = rnMatch match `thenRn` \ (match', fvMatch) -> @@ -214,18 +271,32 @@ rnExpr (HsLam match) rnExpr (HsApp fun arg) = rnExpr fun `thenRn` \ (fun',fvFun) -> rnExpr arg `thenRn` \ (arg',fvArg) -> - returnRn (HsApp fun' arg', fvFun `unionUniqSets` fvArg) - -rnExpr (OpApp e1 op e2) - = rnExpr e1 `thenRn` \ (e1', fvs_e1) -> - rnExpr op `thenRn` \ (op', fvs_op) -> - rnExpr e2 `thenRn` \ (e2', fvs_e2) -> - precParseExpr (OpApp e1' op' e2') `thenRn` \ exp -> - returnRn (exp, (fvs_op `unionUniqSets` fvs_e1) `unionUniqSets` fvs_e2) - -rnExpr (NegApp e) - = rnExpr e `thenRn` \ (e', fvs_e) -> - returnRn (NegApp e', fvs_e) + returnRn (HsApp fun' arg', fvFun `unionNameSets` fvArg) + +rnExpr (OpApp e1 op@(HsVar op_name) _ e2) + = rnExpr e1 `thenRn` \ (e1', fv_e1) -> + rnExpr e2 `thenRn` \ (e2', fv_e2) -> + rnExpr op `thenRn` \ (op', 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 + lookupFixity op_name `thenRn` \ fixity -> + getModeRn `thenRn` \ mode -> + (case mode of + SourceMode -> mkOpAppRn e1' op' fixity e2' + InterfaceMode _ _ -> returnRn (OpApp e1' op' fixity e2') + ) `thenRn` \ final_e -> + + returnRn (final_e, + fv_e1 `unionNameSets` fv_op `unionNameSets` fv_e2) + +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) rnExpr (HsPar e) = rnExpr e `thenRn` \ (e', fvs_e) -> @@ -234,15 +305,20 @@ rnExpr (HsPar e) rnExpr (SectionL expr op) = rnExpr expr `thenRn` \ (expr', fvs_expr) -> rnExpr op `thenRn` \ (op', fvs_op) -> - returnRn (SectionL expr' op', fvs_op `unionUniqSets` fvs_expr) + returnRn (SectionL expr' op', fvs_op `unionNameSets` fvs_expr) rnExpr (SectionR op expr) = rnExpr op `thenRn` \ (op', fvs_op) -> rnExpr expr `thenRn` \ (expr', fvs_expr) -> - returnRn (SectionR op' expr', fvs_op `unionUniqSets` fvs_expr) + returnRn (SectionR op' expr', fvs_op `unionNameSets` fvs_expr) rnExpr (CCall fun args may_gc is_casm fake_result_ty) - = rnExprs args `thenRn` \ (args', fvs_args) -> + -- Check out the comment on RnIfaces.getNonWiredDataDecl about ccalls + = lookupImplicitOccRn ccallableClass_RDR `thenRn_` + lookupImplicitOccRn creturnableClass_RDR `thenRn_` + lookupImplicitOccRn ioDataCon_RDR `thenRn_` + lookupImplicitOccRn ioOkDataCon_RDR `thenRn_` + rnExprs args `thenRn` \ (args', fvs_args) -> returnRn (CCall fun args' may_gc is_casm fake_result_ty, fvs_args) rnExpr (HsSCC label expr) @@ -253,39 +329,42 @@ 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, unionManyUniqSets (e_fvs : ms_fvs)) + returnRn (HsCase new_expr new_ms src_loc, unionManyNameSets (e_fvs : ms_fvs)) rnExpr (HsLet binds expr) - = rnBinds binds `thenRn` \ (binds', fvBinds, new_binders) -> - extendSS2 new_binders (rnExpr expr) `thenRn` \ (expr',fvExpr) -> - returnRn (HsLet binds' expr', fvBinds `unionUniqSets` fvExpr) + = rnBinds binds $ \ binds' -> + rnExpr expr `thenRn` \ (expr',fvExpr) -> + returnRn (HsLet binds' expr', fvExpr) -rnExpr (HsDo stmts src_loc) +rnExpr (HsDo do_or_lc stmts src_loc) = pushSrcLocRn src_loc $ - rnStmts stmts `thenRn` \ (stmts', fvStmts) -> - returnRn (HsDo stmts' src_loc, fvStmts) - -rnExpr (ListComp expr quals) - = rnQuals quals `thenRn` \ ((quals', qual_binders), fvQuals) -> - extendSS2 qual_binders (rnExpr expr) `thenRn` \ (expr', fvExpr) -> - returnRn (ListComp expr' quals', fvExpr `unionUniqSets` fvQuals) + lookupImplicitOccRn monadZeroClass_RDR `thenRn_` -- Forces Monad to come too + (rnStmts rnExpr stmts $ \ stmts' -> + returnRn (HsDo do_or_lc stmts' src_loc, emptyNameSet)) rnExpr (ExplicitList exps) - = rnExprs exps `thenRn` \ (exps', fvs) -> + = addImplicitOccRn listType_name `thenRn_` + rnExprs exps `thenRn` \ (exps', fvs) -> returnRn (ExplicitList exps', fvs) rnExpr (ExplicitTuple exps) - = rnExprs exps `thenRn` \ (exps', fvExps) -> + = addImplicitOccRn (tupleType_name (length exps)) `thenRn_` + rnExprs exps `thenRn` \ (exps', fvExps) -> returnRn (ExplicitTuple exps', fvExps) -rnExpr (RecordCon con rbinds) - = panic "rnExpr:RecordCon" -rnExpr (RecordUpd exp rbinds) - = panic "rnExpr:RecordUpd" +rnExpr (RecordCon con_id _ rbinds) + = lookupOccRn con_id `thenRn` \ conname -> + rnRbinds "construction" rbinds `thenRn` \ (rbinds', fvRbinds) -> + returnRn (RecordCon conname (error "rnExpr:RecordCon") rbinds', fvRbinds) + +rnExpr (RecordUpd expr rbinds) + = rnExpr expr `thenRn` \ (expr', fvExpr) -> + rnRbinds "update" rbinds `thenRn` \ (rbinds', fvRbinds) -> + returnRn (RecordUpd expr' rbinds', fvExpr `unionNameSets` fvRbinds) rnExpr (ExprWithTySig expr pty) - = rnExpr expr `thenRn` \ (expr', fvExpr) -> - rnPolyType nullTyVarNamesEnv pty `thenRn` \ pty' -> + = rnExpr expr `thenRn` \ (expr', fvExpr) -> + rnHsSigType (text "an expression") pty `thenRn` \ pty' -> returnRn (ExprWithTySig expr' pty', fvExpr) rnExpr (HsIf p b1 b2 src_loc) @@ -293,10 +372,11 @@ rnExpr (HsIf p b1 b2 src_loc) rnExpr p `thenRn` \ (p', fvP) -> rnExpr b1 `thenRn` \ (b1', fvB1) -> rnExpr b2 `thenRn` \ (b2', fvB2) -> - returnRn (HsIf p' b1' b2' src_loc, unionManyUniqSets [fvP, fvB1, fvB2]) + returnRn (HsIf p' b1' b2' src_loc, unionManyNameSets [fvP, fvB1, fvB2]) rnExpr (ArithSeqIn seq) - = rn_seq seq `thenRn` \ (new_seq, fvs) -> + = lookupImplicitOccRn enumClass_RDR `thenRn_` + rn_seq seq `thenRn` \ (new_seq, fvs) -> returnRn (ArithSeqIn new_seq, fvs) where rn_seq (From expr) @@ -306,75 +386,55 @@ rnExpr (ArithSeqIn seq) rn_seq (FromThen expr1 expr2) = rnExpr expr1 `thenRn` \ (expr1', fvExpr1) -> rnExpr expr2 `thenRn` \ (expr2', fvExpr2) -> - returnRn (FromThen expr1' expr2', fvExpr1 `unionUniqSets` fvExpr2) + returnRn (FromThen expr1' expr2', fvExpr1 `unionNameSets` fvExpr2) rn_seq (FromTo expr1 expr2) = rnExpr expr1 `thenRn` \ (expr1', fvExpr1) -> rnExpr expr2 `thenRn` \ (expr2', fvExpr2) -> - returnRn (FromTo expr1' expr2', fvExpr1 `unionUniqSets` fvExpr2) + returnRn (FromTo expr1' expr2', fvExpr1 `unionNameSets` 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', - unionManyUniqSets [fvExpr1, fvExpr2, fvExpr3]) - + unionManyNameSets [fvExpr1, fvExpr2, fvExpr3]) \end{code} %************************************************************************ %* * -\subsubsection{@Qual@s: in list comprehensions} +\subsubsection{@Rbinds@s and @Rpats@s: in record 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} -rnQuals :: [RdrNameQual] - -> RnM_Fixes s (([RenamedQual], -- renamed qualifiers - [RnName]), -- qualifiers' binders - FreeVars) -- free variables - -rnQuals [qual] -- must be at least one qual - = rnQual qual `thenRn` \ ((new_qual, bs), fvs) -> - returnRn (([new_qual], bs), fvs) - -rnQuals (qual: quals) - = rnQual qual `thenRn` \ ((qual', bs1), fvQuals1) -> - extendSS2 bs1 (rnQuals quals) `thenRn` \ ((quals', bs2), fvQuals2) -> - returnRn - ((qual' : quals', bs2 ++ bs1), -- The ones on the right (bs2) shadow the - -- ones on the left (bs1) - fvQuals1 `unionUniqSets` fvQuals2) - -rnQual (GeneratorQual pat expr) - = rnExpr expr `thenRn` \ (expr', fvExpr) -> - let - binders = collectPatBinders pat - in - getSrcLocRn `thenRn` \ src_loc -> - newLocalNames "variable in list-comprehension-generator pattern" - (binders `zip` repeat src_loc) `thenRn` \ new_binders -> - extendSS new_binders (rnPat pat) `thenRn` \ pat' -> +rnRbinds str rbinds + = mapRn field_dup_err dup_fields `thenRn_` + mapAndUnzipRn rn_rbind rbinds `thenRn` \ (rbinds', fvRbind_s) -> + returnRn (rbinds', unionManyNameSets fvRbind_s) + where + (_, dup_fields) = removeDups compare [ f | (f,_,_) <- rbinds ] - returnRn ((GeneratorQual pat' expr', new_binders), fvExpr) + field_dup_err dups = addErrRn (dupFieldErr str dups) -rnQual (FilterQual expr) - = rnExpr expr `thenRn` \ (expr', fvs) -> - returnRn ((FilterQual expr', []), fvs) + rn_rbind (field, expr, pun) + = lookupGlobalOccRn field `thenRn` \ fieldname -> + rnExpr expr `thenRn` \ (expr', fvExpr) -> + returnRn ((fieldname, expr', pun), fvExpr) -rnQual (LetQual binds) - = rnBinds binds `thenRn` \ (binds', binds_fvs, new_binders) -> - returnRn ((LetQual binds', new_binders), binds_fvs) -\end{code} +rnRpats rpats + = mapRn field_dup_err dup_fields `thenRn_` + mapRn rn_rpat rpats + where + (_, dup_fields) = removeDups compare [ f | (f,_,_) <- rpats ] + + field_dup_err dups = addErrRn (dupFieldErr "pattern" dups) + rn_rpat (field, pat, pun) + = lookupGlobalOccRn field `thenRn` \ fieldname -> + rnPat pat `thenRn` \ pat' -> + returnRn (fieldname, pat', pun) +\end{code} %************************************************************************ %* * @@ -382,40 +442,64 @@ rnQual (LetQual binds) %* * %************************************************************************ +Note that although some bound vars may appear in the free var set for +the first qual, these will eventually be removed by the caller. For +example, if we have @[p | r <- s, q <- r, p <- q]@, when doing +@[q <- r, p <- q]@, the free var set for @q <- r@ will +be @{r}@, and the free var set for the entire Quals will be @{r}@. This +@r@ will be removed only when we finally return from examining all the +Quals. + \begin{code} -rnStmts :: [RdrNameStmt] -> RnM_Fixes s ([RenamedStmt], FreeVars) +type RnExprTy s = RdrNameHsExpr -> RnMS s (RenamedHsExpr, FreeVars) -rnStmts [stmt@(ExprStmt _ _)] -- last stmt must be ExprStmt - = rnStmt stmt `thenRn` \ ((stmt',[]), fvStmt) -> - returnRn ([stmt'], fvStmt) +rnStmts :: RnExprTy s + -> [RdrNameStmt] + -> ([RenamedStmt] -> RnMS s (a, FreeVars)) + -> RnMS s (a, FreeVars) -rnStmts (stmt:stmts) - = rnStmt stmt `thenRn` \ ((stmt',bs), fvStmt) -> - extendSS2 bs (rnStmts stmts) `thenRn` \ (stmts', fvStmts) -> - returnRn (stmt':stmts', fvStmt `unionUniqSets` fvStmts) +rnStmts rn_expr [] thing_inside + = thing_inside [] +rnStmts rn_expr (stmt:stmts) thing_inside + = rnStmt rn_expr stmt $ \ stmt' -> + rnStmts rn_expr stmts $ \ stmts' -> + thing_inside (stmt' : stmts') -rnStmt (BindStmt pat expr src_loc) - = pushSrcLocRn src_loc $ - rnExpr expr `thenRn` \ (expr', fvExpr) -> - let - binders = collectPatBinders pat - in - newLocalNames "variable in do binding" - (binders `zip` repeat src_loc) `thenRn` \ new_binders -> - extendSS new_binders (rnPat pat) `thenRn` \ pat' -> +rnStmt :: RnExprTy s -> RdrNameStmt -> (RenamedStmt -> RnMS s (a, FreeVars)) -> RnMS s (a, FreeVars) +-- Because of mutual recursion we have to pass in rnExpr. - returnRn ((BindStmt pat' expr' src_loc, new_binders), fvExpr) +rnStmt rn_expr (BindStmt pat expr src_loc) thing_inside + = pushSrcLocRn src_loc $ + rn_expr expr `thenRn` \ (expr', fv_expr) -> + bindLocalsRn "pattern in do binding" binders $ \ new_binders -> + rnPat pat `thenRn` \ pat' -> -rnStmt (ExprStmt expr src_loc) - = - rnExpr expr `thenRn` \ (expr', fvs) -> - returnRn ((ExprStmt expr' src_loc, []), fvs) + thing_inside (BindStmt pat' expr' src_loc) `thenRn` \ (result, fvs) -> + returnRn (result, fv_expr `unionNameSets` (fvs `minusNameSet` mkNameSet new_binders)) + where + binders = collectPatBinders pat -rnStmt (LetStmt binds) - = rnBinds binds `thenRn` \ (binds', binds_fvs, new_binders) -> - returnRn ((LetStmt binds', new_binders), binds_fvs) +rnStmt rn_expr (ExprStmt expr src_loc) thing_inside + = pushSrcLocRn src_loc $ + rn_expr expr `thenRn` \ (expr', fv_expr) -> + thing_inside (ExprStmt expr' src_loc) `thenRn` \ (result, fvs) -> + returnRn (result, fv_expr `unionNameSets` 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 `unionNameSets` 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 `unionNameSets` fvs) + +rnStmt rn_expr (LetStmt binds) thing_inside + = rnBinds binds $ \ binds' -> + thing_inside (LetStmt binds') \end{code} %************************************************************************ @@ -424,81 +508,112 @@ rnStmt (LetStmt binds) %* * %************************************************************************ -\begin{code} -precParseExpr :: RenamedHsExpr -> RnM_Fixes s RenamedHsExpr -precParsePat :: RenamedPat -> RnM_Fixes s RenamedPat - -precParseExpr exp@(OpApp (NegApp e1) (HsVar op) e2) - = lookupFixity op `thenRn` \ (op_fix, op_prec) -> - if 6 < op_prec then - -- negate precedence 6 wired in - -- (-x)*y ==> -(x*y) - precParseExpr (OpApp e1 (HsVar op) e2) `thenRn` \ op_app -> - returnRn (NegApp op_app) - else - returnRn exp - -precParseExpr exp@(OpApp (OpApp e11 (HsVar op1) e12) (HsVar op) e2) - = lookupFixity op `thenRn` \ (op_fix, op_prec) -> - lookupFixity op1 `thenRn` \ (op1_fix, op1_prec) -> - case cmp op1_prec op_prec of - LT_ -> rearrange - EQ_ -> case (op1_fix, op_fix) of - (INFIXR, INFIXR) -> rearrange - (INFIXL, INFIXL) -> returnRn exp - _ -> getSrcLocRn `thenRn` \ src_loc -> - failButContinueRn exp - (precParseErr (op1,op1_fix,op1_prec) (op,op_fix,op_prec) src_loc) - GT__ -> returnRn exp - where - rearrange = precParseExpr (OpApp e12 (HsVar op) e2) `thenRn` \ e2' -> - returnRn (OpApp e11 (HsVar op1) e2') - -precParseExpr exp = returnRn exp +@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. -precParsePat pat@(ConOpPatIn (NegPatIn e1) op e2) - = lookupFixity op `thenRn` \ (op_fix, op_prec) -> - if 6 < op_prec then - -- negate precedence 6 wired in - getSrcLocRn `thenRn` \ src_loc -> - failButContinueRn pat (precParseNegPatErr (op,op_fix,op_prec) src_loc) - else - returnRn pat - -precParsePat pat@(ConOpPatIn (ConOpPatIn p11 op1 p12) op p2) - = lookupFixity op `thenRn` \ (op_fix, op_prec) -> - lookupFixity op1 `thenRn` \ (op1_fix, op1_prec) -> - case cmp op1_prec op_prec of - LT_ -> rearrange - EQ_ -> case (op1_fix, op_fix) of - (INFIXR, INFIXR) -> rearrange - (INFIXL, INFIXL) -> returnRn pat - _ -> getSrcLocRn `thenRn` \ src_loc -> - failButContinueRn pat - (precParseErr (op1,op1_fix,op1_prec) (op,op_fix,op_prec) src_loc) - GT__ -> returnRn pat +\begin{code} +mkOpAppRn :: RenamedHsExpr -> RenamedHsExpr -> Fixity -> RenamedHsExpr + -> RnMS s RenamedHsExpr + +mkOpAppRn e1@(OpApp e11 op1 fix1 e12) + op2 fix2 e2 + | nofix_error + = addErrRn (precParseErr (get op1,fix1) (get op2,fix2)) `thenRn_` + returnRn (OpApp e1 op2 fix2 e2) + + | rearrange_me + = mkOpAppRn e12 op2 fix2 e2 `thenRn` \ new_e -> + returnRn (OpApp e11 op1 fix1 new_e) + where + (nofix_error, rearrange_me) = compareFixity fix1 fix2 + +mkOpAppRn e1@(NegApp neg_arg neg_op) + op2 + fix2@(Fixity prec2 dir2) + e2 + | nofix_error + = addErrRn (precParseErr (get neg_op,fix_neg) (get op2,fix2)) `thenRn_` + returnRn (OpApp e1 op2 fix2 e2) + + | rearrange_me + = mkOpAppRn neg_arg op2 fix2 e2 `thenRn` \ new_e -> + returnRn (NegApp new_e neg_op) + where + fix_neg = Fixity 6 InfixL -- Precedence of unary negate is wired in as infixl 6! + (nofix_error, rearrange_me) = compareFixity fix_neg fix2 + +mkOpAppRn e1 op fix e2 -- Default case, no rearrangment + = ASSERT( if right_op_ok fix e2 then True + else pprPanic "mkOpAppRn" (vcat [ppr e1, text "---", ppr op, text "---", ppr fix, text "---", ppr e2]) + ) + returnRn (OpApp e1 op fix e2) + +get (HsVar n) = n + +-- 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 - rearrange = precParsePat (ConOpPatIn p12 op p2) `thenRn` \ p2' -> - returnRn (ConOpPatIn p11 op1 p2') + (error_please, associate_right) = compareFixity fix1 fix2 +right_op_ok fix1 other + = True -precParsePat pat = returnRn pat +-- 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} +mkConOpPatRn :: RenamedPat -> Name -> Fixity -> RenamedPat + -> RnMS s RenamedPat -data INFIX = INFIXL | INFIXR | INFIXN deriving Eq +mkConOpPatRn p1@(ConOpPatIn p11 op1 fix1 p12) + op2 fix2 p2 + | nofix_error + = addErrRn (precParseErr (op1,fix1) (op2,fix2)) `thenRn_` + returnRn (ConOpPatIn p1 op2 fix2 p2) -lookupFixity :: RnName -> RnM_Fixes s (INFIX, Int) -lookupFixity op - = getExtraRn `thenRn` \ fixity_fm -> - case lookupUFM fixity_fm op of - Nothing -> returnRn (INFIXL, 9) - Just (InfixL _ n) -> returnRn (INFIXL, n) - Just (InfixR _ n) -> returnRn (INFIXR, n) - Just (InfixN _ n) -> returnRn (INFIXN, n) + | rearrange_me + = mkConOpPatRn p12 op2 fix2 p2 `thenRn` \ new_p -> + returnRn (ConOpPatIn p11 op1 fix1 new_p) + + where + (nofix_error, rearrange_me) = compareFixity fix1 fix2 + +mkConOpPatRn p1@(NegPatIn neg_arg) + op2 + fix2@(Fixity prec2 dir2) + p2 + | prec2 > 6 -- Precedence of unary - is wired in as 6! + = addErrRn (precParseNegPatErr (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 -> RnName -> RenamedMatch -> RnM_Fixes s () +checkPrecMatch :: Bool -> RdrName -> RdrNameMatch -> RnMS s () checkPrecMatch False fn match = returnRn () @@ -508,47 +623,154 @@ checkPrecMatch True op (PatMatch p1 (PatMatch p2 (GRHSMatch _))) checkPrecMatch True op _ = panic "checkPrecMatch" -checkPrec op (ConOpPatIn _ op1 _) right - = lookupFixity op `thenRn` \ (op_fix, op_prec) -> - lookupFixity op1 `thenRn` \ (op1_fix, op1_prec) -> - getSrcLocRn `thenRn` \ src_loc -> +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 inf_ok = op1_prec > op_prec || (op1_prec == op_prec && - (op1_fix == INFIXR && op_fix == INFIXR && right || - op1_fix == INFIXL && op_fix == INFIXL && not right)) + (op1_dir == InfixR && op_dir == InfixR && right || + op1_dir == InfixL && op_dir == InfixL && not right)) - info = (op,op_fix,op_prec) - info1 = (op1,op1_fix,op1_prec) + info = (op,op_fix) + info1 = (op1,op1_fix) (infol, infor) = if right then (info, info1) else (info1, info) in - addErrIfRn (not inf_ok) (precParseErr infol infor src_loc) + checkRn inf_ok (precParseErr infol infor) checkPrec op (NegPatIn _) right - = lookupFixity op `thenRn` \ (op_fix, op_prec) -> - getSrcLocRn `thenRn` \ src_loc -> - addErrIfRn (6 < op_prec) (precParseNegPatErr (op,op_fix,op_prec) src_loc) + = lookupFixity op `thenRn` \ op_fix@(Fixity op_prec op_dir) -> + checkRn (op_prec <= 6) (precParseNegPatErr (op,op_fix)) checkPrec op pat right = returnRn () \end{code} +Consider + a `op1` b `op2` c + +(compareFixity op1 op2) tells which way to arrange appication, or +whether there's an error. + +\begin{code} +compareFixity :: Fixity -> Fixity + -> (Bool, -- Error please + Bool) -- Associate to the right: a op1 (b op2 c) +compareFixity (Fixity prec1 dir1) (Fixity prec2 dir2) + = case prec1 `compare` prec2 of + GT -> left + LT -> right + EQ -> case (dir1, dir2) of + (InfixR, InfixR) -> right + (InfixL, InfixL) -> left + _ -> error_please + where + right = (False, True) + left = (False, False) + error_please = (True, False) +\end{code} + +%************************************************************************ +%* * +\subsubsection{Literals} +%* * +%************************************************************************ + +When literals occur we have to make sure that the types and classes they involve +are made available. + +\begin{code} +litOccurrence (HsChar _) + = addImplicitOccRn charType_name + +litOccurrence (HsCharPrim _) + = addImplicitOccRn (getName charPrimTyCon) + +litOccurrence (HsString _) + = addImplicitOccRn listType_name `thenRn_` + addImplicitOccRn charType_name + +litOccurrence (HsStringPrim _) + = addImplicitOccRn (getName addrPrimTyCon) + +litOccurrence (HsInt _) + = lookupImplicitOccRn numClass_RDR -- Int and Integer are forced in by Num + +litOccurrence (HsFrac _) + = lookupImplicitOccRn fractionalClass_RDR `thenRn_` + lookupImplicitOccRn ratioDataCon_RDR + -- We have to make sure that the Ratio type is imported with + -- its constructor, because literals of type Ratio t are + -- built with that constructor. + -- The Rational type is needed too, but that will come in + -- when fractionalClass does. + +litOccurrence (HsIntPrim _) + = addImplicitOccRn (getName intPrimTyCon) + +litOccurrence (HsFloatPrim _) + = addImplicitOccRn (getName floatPrimTyCon) + +litOccurrence (HsDoublePrim _) + = addImplicitOccRn (getName doublePrimTyCon) + +litOccurrence (HsLitLit _) + = lookupImplicitOccRn ccallableClass_RDR +\end{code} + +%************************************************************************ +%* * +\subsubsection{Assertion utils} +%* * +%************************************************************************ + +\begin{code} +mkAssertExpr :: RnMS s RenamedHsExpr +mkAssertExpr = + newImportedGlobalName mod occ HiFile `thenRn` \ name -> + addOccurrenceName name `thenRn_` + getSrcLocRn `thenRn` \ sloc -> + let + expr = HsApp (HsVar name) + (HsLit (HsString (_PK_ (showSDoc (ppr sloc))))) + in + returnRn expr + + where + mod = rdrNameModule assertErr_RDR + occ = rdrNameOcc assertErr_RDR +\end{code} + +%************************************************************************ +%* * +\subsubsection{Errors} +%* * +%************************************************************************ + \begin{code} -negPatErr pat src_loc - = addErrLoc src_loc "prefix `-' not applied to literal in pattern" ( \sty -> - ppr sty pat) - -precParseNegPatErr op src_loc - = addErrLoc src_loc "precedence parsing error" (\ sty -> - ppBesides [ppStr "prefix `-' has lower precedence than ", pp_op sty op, ppStr " in pattern"]) - -precParseErr op1 op2 src_loc - = addErrLoc src_loc "precedence parsing error" (\ sty -> - ppBesides [ppStr "cannot mix ", pp_op sty op1, ppStr " and ", pp_op sty op2, - ppStr " in the same infix expression"]) - -pp_op sty (op, fix, prec) = ppBesides [pprOp sty op, ppLparen, pp_fix fix, ppSP, ppInt prec, ppRparen] -pp_fix INFIXL = ppStr "infixl" -pp_fix INFIXR = ppStr "infixr" -pp_fix INFIXN = ppStr "infix" +dupFieldErr str (dup:rest) + = hsep [ptext SLIT("duplicate field name"), + quotes (ppr dup), + ptext SLIT("in record"), text str] + +negPatErr pat + = sep [ptext SLIT("prefix `-' not applied to literal in pattern"), quotes (ppr pat)] + +precParseNegPatErr op + = hang (ptext SLIT("precedence parsing error")) + 4 (hsep [ptext SLIT("prefix `-' has lower precedence than"), + quotes (pp_op op), + ptext SLIT("in pattern")]) + +precParseErr op1 op2 + = hang (ptext SLIT("precedence parsing error")) + 4 (hsep [ptext SLIT("cannot mix"), quotes (pp_op op1), ptext SLIT("and"), + quotes (pp_op op2), + ptext SLIT("in the same infix expression")]) + +nonStdGuardErr guard + = hang (ptext SLIT("accepting non-standard pattern guards (-fglasgow-exts to suppress this message)")) + 4 (ppr guard) + +pp_op (op, fix) = hcat [ppr op, space, parens (ppr fix)] \end{code}