X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FhsSyn%2FHsUtils.lhs;h=3eaae63e641b64a0669cf9f4e8d8ec514b0a9716;hb=155cf24cf7fc7bf7c347aa9709b7ec0ef806224d;hp=d9c45e6529c177edea88066958f869a35576627a;hpb=0065d5ab628975892cea1ec7303f968c3338cbe1;p=ghc-hetmet.git diff --git a/compiler/hsSyn/HsUtils.lhs b/compiler/hsSyn/HsUtils.lhs index d9c45e6..3eaae63 100644 --- a/compiler/hsSyn/HsUtils.lhs +++ b/compiler/hsSyn/HsUtils.lhs @@ -1,5 +1,5 @@ % -% (c) The University of Glasgow, 1992-2003 +% (c) The University of Glasgow, 1992-2006 % Here we collect a variety of helper functions that construct or @@ -13,6 +13,13 @@ which deal with the intantiated versions are located elsewhere: Id typecheck/TcHsSyn \begin{code} +{-# OPTIONS -w #-} +-- The above warning supression flag is a temporary kludge. +-- While working on this module you are encouraged to remove it and fix +-- any warnings in the module. See +-- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings +-- for details + module HsUtils where #include "HsVersions.h" @@ -23,17 +30,17 @@ import HsPat import HsTypes import HsLit -import RdrName ( RdrName, getRdrName, mkRdrUnqual ) -import Var ( Id ) -import Type ( Type ) -import DataCon ( DataCon, dataConWrapId, dataConSourceArity ) -import OccName ( mkVarOccFS ) -import Name ( Name ) -import BasicTypes ( RecFlag(..) ) +import RdrName +import Var +import Coercion +import Type +import DataCon +import Name +import BasicTypes import SrcLoc -import FastString ( mkFastString ) +import FastString import Outputable -import Util ( nOfThem ) +import Util import Bag \end{code} @@ -52,16 +59,18 @@ just attach noSrcSpan to everything. mkHsPar :: LHsExpr id -> LHsExpr id mkHsPar e = L (getLoc e) (HsPar e) --- gaw 2004 mkSimpleMatch :: [LPat id] -> LHsExpr id -> LMatch id mkSimpleMatch pats rhs = L loc $ - Match pats Nothing (GRHSs (unguardedRHS rhs) emptyLocalBinds) + Match pats Nothing (unguardedGRHSs rhs) where loc = case pats of [] -> getLoc rhs (pat:_) -> combineSrcSpans (getLoc pat) (getLoc rhs) +unguardedGRHSs :: LHsExpr id -> GRHSs id +unguardedGRHSs rhs = GRHSs (unguardedRHS rhs) emptyLocalBinds + unguardedRHS :: LHsExpr id -> [LGRHS id] unguardedRHS rhs@(L loc _) = [L loc (GRHS [] rhs)] @@ -71,17 +80,23 @@ mkHsAppTy t1 t2 = addCLoc t1 t2 (HsAppTy t1 t2) mkHsApp :: LHsExpr name -> LHsExpr name -> LHsExpr name mkHsApp e1 e2 = addCLoc e1 e2 (HsApp e1 e2) -mkHsTyApp :: LHsExpr name -> [Type] -> LHsExpr name -mkHsTyApp expr [] = expr -mkHsTyApp expr tys = L (getLoc expr) (TyApp expr tys) +nlHsTyApp :: name -> [Type] -> LHsExpr name +nlHsTyApp fun_id tys = noLoc (HsWrap (mkWpTyApps tys) (HsVar fun_id)) + +mkLHsWrap :: HsWrapper -> LHsExpr id -> LHsExpr id +mkLHsWrap co_fn (L loc e) = L loc (mkHsWrap co_fn e) + +mkHsWrap :: HsWrapper -> HsExpr id -> HsExpr id +mkHsWrap co_fn e | isIdHsWrapper co_fn = e + | otherwise = HsWrap co_fn e -mkHsDictApp :: LHsExpr name -> [name] -> LHsExpr name -mkHsDictApp expr [] = expr -mkHsDictApp expr dict_vars = L (getLoc expr) (DictApp expr dict_vars) +mkHsWrapCoI :: CoercionI -> HsExpr id -> HsExpr id +mkHsWrapCoI IdCo e = e +mkHsWrapCoI (ACo co) e = mkHsWrap (WpCo co) e -mkHsCoerce :: ExprCoFn -> HsExpr id -> HsExpr id -mkHsCoerce co_fn e | isIdCoercion co_fn = e - | otherwise = HsCoerce co_fn e +coiToHsWrapper :: CoercionI -> HsWrapper +coiToHsWrapper IdCo = idHsWrapper +coiToHsWrapper (ACo co) = WpCo co mkHsLam :: [LPat id] -> LHsExpr id -> LHsExpr id mkHsLam pats body = mkHsPar (L (getLoc body) (HsLam matches)) @@ -91,12 +106,6 @@ mkHsLam pats body = mkHsPar (L (getLoc body) (HsLam matches)) mkMatchGroup :: [LMatch id] -> MatchGroup id mkMatchGroup matches = MatchGroup matches placeHolderType -mkHsTyLam [] expr = expr -mkHsTyLam tyvars expr = L (getLoc expr) (TyLam tyvars expr) - -mkHsDictLam [] expr = expr -mkHsDictLam dicts expr = L (getLoc expr) (DictLam dicts expr) - mkHsDictLet :: LHsBinds Id -> LHsExpr Id -> LHsExpr Id -- Used for the dictionary bindings gotten from TcSimplify -- We make them recursive to be on the safe side @@ -107,9 +116,9 @@ mkHsDictLet binds expr val_binds = ValBindsOut [(Recursive, binds)] [] mkHsConApp :: DataCon -> [Type] -> [HsExpr Id] -> LHsExpr Id --- Used for constructing dictinoary terms etc, so no locations +-- Used for constructing dictionary terms etc, so no locations mkHsConApp data_con tys args - = foldl mk_app (noLoc (HsVar (dataConWrapId data_con)) `mkHsTyApp` tys) args + = foldl mk_app (nlHsTyApp (dataConWrapId data_con) tys) args where mk_app f a = noLoc (HsApp f (noLoc a)) @@ -124,9 +133,10 @@ mkSimpleHsAlt pat expr mkHsIntegral i = HsIntegral i noSyntaxExpr mkHsFractional f = HsFractional f noSyntaxExpr +mkHsIsString s = HsIsString s noSyntaxExpr mkHsDo ctxt stmts body = HsDo ctxt stmts body placeHolderType -mkNPat lit neg = NPat lit neg noSyntaxExpr placeHolderType +mkNPat lit neg = NPat lit neg noSyntaxExpr mkNPlusKPat id lit = NPlusKPat id lit noSyntaxExpr noSyntaxExpr mkExprStmt expr = ExprStmt expr noSyntaxExpr placeHolderType @@ -218,6 +228,8 @@ nlList exprs = noLoc (ExplicitList placeHolderType exprs) nlHsAppTy f t = noLoc (HsAppTy f t) nlHsTyVar x = noLoc (HsTyVar x) nlHsFunTy a b = noLoc (HsFunTy a b) + +nlHsTyConApp tycon tys = foldl nlHsAppTy (nlHsTyVar tycon) tys \end{code} @@ -232,23 +244,24 @@ nlHsFunTy a b = noLoc (HsFunTy a b) mkFunBind :: Located id -> [LMatch id] -> HsBind id -- Not infix, with place holders for coercion and free vars mkFunBind fn ms = FunBind { fun_id = fn, fun_infix = False, fun_matches = mkMatchGroup ms, - fun_co_fn = idCoercion, bind_fvs = placeHolderNames } + fun_co_fn = idHsWrapper, bind_fvs = placeHolderNames, + fun_tick = Nothing } -mkVarBind :: SrcSpan -> RdrName -> LHsExpr RdrName -> LHsBind RdrName +mkVarBind :: SrcSpan -> id -> LHsExpr id -> LHsBind id mkVarBind loc var rhs = mk_easy_FunBind loc var [] rhs ------------ -mk_easy_FunBind :: SrcSpan -> RdrName -> [LPat RdrName] - -> LHsExpr RdrName -> LHsBind RdrName +mk_easy_FunBind :: SrcSpan -> id -> [LPat id] + -> LHsExpr id -> LHsBind id mk_easy_FunBind loc fun pats expr = L loc $ mkFunBind (L loc fun) [mkMatch pats expr emptyLocalBinds] ------------ -mk_FunBind :: SrcSpan -> RdrName - -> [([LPat RdrName], LHsExpr RdrName)] - -> LHsBind RdrName +mk_FunBind :: SrcSpan -> id + -> [([LPat id], LHsExpr id)] + -> LHsBind id mk_FunBind loc fun [] = panic "TcGenDeriv:mk_FunBind" mk_FunBind loc fun pats_and_exprs @@ -285,18 +298,18 @@ where it should return [x, y, f, a, b] (remember, order important). \begin{code} -collectLocalBinders :: HsLocalBinds name -> [Located name] +collectLocalBinders :: HsLocalBindsLR idL idR -> [Located idL] collectLocalBinders (HsValBinds val_binds) = collectHsValBinders val_binds collectLocalBinders (HsIPBinds _) = [] collectLocalBinders EmptyLocalBinds = [] -collectHsValBinders :: HsValBinds name -> [Located name] +collectHsValBinders :: HsValBindsLR idL idR -> [Located idL] collectHsValBinders (ValBindsIn binds sigs) = collectHsBindLocatedBinders binds collectHsValBinders (ValBindsOut binds sigs) = foldr collect_one [] binds where collect_one (_,binds) acc = foldrBag (collectAcc . unLoc) acc binds -collectAcc :: HsBind name -> [Located name] -> [Located name] +collectAcc :: HsBindLR idL idR -> [Located idL] -> [Located idL] collectAcc (PatBind { pat_lhs = p }) acc = collectLocatedPatBinders p ++ acc collectAcc (FunBind { fun_id = f }) acc = f : acc collectAcc (VarBind { var_id = f }) acc = noLoc f : acc @@ -307,10 +320,10 @@ collectAcc (AbsBinds { abs_exports = dbinds, abs_binds = binds }) acc -- The only time we collect binders from a typechecked -- binding (hence see AbsBinds) is in zonking in TcHsSyn -collectHsBindBinders :: LHsBinds name -> [name] +collectHsBindBinders :: LHsBindsLR idL idR -> [idL] collectHsBindBinders binds = map unLoc (collectHsBindLocatedBinders binds) -collectHsBindLocatedBinders :: LHsBinds name -> [Located name] +collectHsBindLocatedBinders :: LHsBindsLR idL idR -> [Located idL] collectHsBindLocatedBinders binds = foldrBag (collectAcc . unLoc) [] binds \end{code} @@ -322,22 +335,23 @@ collectHsBindLocatedBinders binds = foldrBag (collectAcc . unLoc) [] binds %************************************************************************ \begin{code} -collectLStmtsBinders :: [LStmt id] -> [Located id] +collectLStmtsBinders :: [LStmtLR idL idR] -> [Located idL] collectLStmtsBinders = concatMap collectLStmtBinders -collectStmtsBinders :: [Stmt id] -> [Located id] +collectStmtsBinders :: [StmtLR idL idR] -> [Located idL] collectStmtsBinders = concatMap collectStmtBinders -collectLStmtBinders :: LStmt id -> [Located id] +collectLStmtBinders :: LStmtLR idL idR -> [Located idL] collectLStmtBinders = collectStmtBinders . unLoc -collectStmtBinders :: Stmt id -> [Located id] +collectStmtBinders :: StmtLR idL idR -> [Located idL] -- Id Binders for a Stmt... [but what about pattern-sig type vars]? collectStmtBinders (BindStmt pat _ _ _) = collectLocatedPatBinders pat collectStmtBinders (LetStmt binds) = collectLocalBinders binds -collectStmtBinders (ExprStmt _ _ _) = [] -collectStmtBinders (RecStmt ss _ _ _ _) = collectLStmtsBinders ss -collectStmtBinders other = panic "collectStmtBinders" +collectStmtBinders (ExprStmt _ _ _) = [] +collectStmtBinders (ParStmt xs) = collectLStmtsBinders + $ concatMap fst xs +collectStmtBinders (RecStmt ss _ _ _ _) = collectLStmtsBinders ss \end{code} @@ -378,27 +392,52 @@ collectl (L l pat) bndrs go (LazyPat pat) = collectl pat bndrs go (BangPat pat) = collectl pat bndrs go (AsPat a pat) = a : collectl pat bndrs + go (ViewPat exp pat _) = collectl pat bndrs go (ParPat pat) = collectl pat bndrs go (ListPat pats _) = foldr collectl bndrs pats go (PArrPat pats _) = foldr collectl bndrs pats go (TuplePat pats _ _) = foldr collectl bndrs pats - go (ConPatIn c ps) = foldr collectl bndrs (hsConArgs ps) - go (ConPatOut c _ ds bs ps _) = map noLoc ds - ++ collectHsBindLocatedBinders bs - ++ foldr collectl bndrs (hsConArgs ps) + go (ConPatIn c ps) = foldr collectl bndrs (hsConPatArgs ps) + go (ConPatOut {pat_args=ps}) = foldr collectl bndrs (hsConPatArgs ps) + -- See Note [Dictionary binders in ConPatOut] go (LitPat _) = bndrs - go (NPat _ _ _ _) = bndrs + go (NPat _ _ _) = bndrs go (NPlusKPat n _ _ _) = n : bndrs - + go (SigPatIn pat _) = collectl pat bndrs go (SigPatOut pat _) = collectl pat bndrs go (TypePat ty) = bndrs - go (DictPat ids1 ids2) = map noLoc ids1 ++ map noLoc ids2 - ++ bndrs + go (CoPat _ pat ty) = collectl (noLoc pat) bndrs \end{code} +Note [Dictionary binders in ConPatOut] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Do *not* gather (a) dictionary and (b) dictionary bindings as binders +of a ConPatOut pattern. For most calls it doesn't matter, because +it's pre-typechecker and there are no ConPatOuts. But it does matter +more in the desugarer; for example, DsUtils.mkSelectorBinds uses +collectPatBinders. In a lazy pattern, for example f ~(C x y) = ..., +we want to generate bindings for x,y but not for dictionaries bound by +C. (The type checker ensures they would not be used.) + +Desugaring of arrow case expressions needs these bindings (see DsArrows +and arrowcase1), but SPJ (Jan 2007) says it's safer for it to use its +own pat-binder-collector: + +Here's the problem. Consider + +data T a where + C :: Num a => a -> Int -> T a + +f ~(C (n+1) m) = (n,m) + +Here, the pattern (C (n+1)) binds a hidden dictionary (d::Num a), +and *also* uses that dictionary to match the (n+1) pattern. Yet, the +variables bound by the lazy pattern are n,m, *not* the dictionary d. +So in mkSelectorBinds in DsUtils, we want just m,n as the variables bound. + \begin{code} collectSigTysFromPats :: [InPat name] -> [LHsType name] collectSigTysFromPats pats = foldr collect_lpat [] pats @@ -418,6 +457,6 @@ collect_pat (ParPat pat) acc = collect_lpat pat acc collect_pat (ListPat pats _) acc = foldr collect_lpat acc pats collect_pat (PArrPat pats _) acc = foldr collect_lpat acc pats collect_pat (TuplePat pats _ _) acc = foldr collect_lpat acc pats -collect_pat (ConPatIn c ps) acc = foldr collect_lpat acc (hsConArgs ps) +collect_pat (ConPatIn c ps) acc = foldr collect_lpat acc (hsConPatArgs ps) collect_pat other acc = acc -- Literals, vars, wildcard \end{code}