X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2Ftypecheck%2FInst.lhs;h=be7c14ae70db0fadb19f7b16df46225905918ec4;hb=f5edc6b0871a0debbc9a64f4cdb95c0dc35e5b16;hp=d75a7cd290c59c0252668d98d4638fbe06c35e27;hpb=2e68d0410f319a99f3f36c5e9d9be656ca10dc70;p=ghc-hetmet.git diff --git a/compiler/typecheck/Inst.lhs b/compiler/typecheck/Inst.lhs index d75a7cd..be7c14a 100644 --- a/compiler/typecheck/Inst.lhs +++ b/compiler/typecheck/Inst.lhs @@ -23,9 +23,8 @@ module Inst ( newDictBndr, newDictBndrs, newDictBndrsO, instCall, instStupidTheta, - cloneDict, - shortCutFracLit, shortCutIntLit, shortCutStringLit, newIPDict, - newMethod, newMethodFromName, newMethodWithGivenTy, + cloneDict, mkOverLit, + newIPDict, newMethod, newMethodFromName, newMethodWithGivenTy, tcInstClassOp, tcSyntaxName, isHsVar, @@ -60,7 +59,7 @@ module Inst ( import {-# SOURCE #-} TcExpr( tcPolyExpr ) import {-# SOURCE #-} TcUnify( boxyUnify, unifyType ) -import FastString(FastString) +import FastString import HsSyn import TcHsSyn import TcRnMonad @@ -94,12 +93,13 @@ import DynFlags import Bag import Maybes import Util +import Unique import Outputable import Data.List import TypeRep import Class -import Control.Monad ( liftM ) +import Control.Monad \end{code} @@ -366,15 +366,15 @@ cloneDict other = pprPanic "cloneDict" (ppr other) -- scope, so we make up a new namea. newIPDict :: InstOrigin -> IPName Name -> Type -> TcM (IPName Id, Inst) -newIPDict orig ip_name ty - = getInstLoc orig `thenM` \ inst_loc -> - newUnique `thenM` \ uniq -> +newIPDict orig ip_name ty = do + inst_loc <- getInstLoc orig + uniq <- newUnique let pred = IParam ip_name ty name = mkPredName uniq inst_loc pred dict = Dict {tci_name = name, tci_pred = pred, tci_loc = inst_loc} - in - returnM (mapIPName (\n -> instToId dict) ip_name, dict) + + return (mapIPName (\n -> instToId dict) ip_name, dict) \end{code} @@ -404,22 +404,22 @@ mkPredName uniq loc pred_ty \begin{code} newMethodFromName :: InstOrigin -> BoxyRhoType -> Name -> TcM TcId -newMethodFromName origin ty name - = tcLookupId name `thenM` \ id -> +newMethodFromName origin ty name = do + id <- tcLookupId name -- Use tcLookupId not tcLookupGlobalId; the method is almost -- always a class op, but with -fno-implicit-prelude GHC is -- meant to find whatever thing is in scope, and that may -- be an ordinary function. - getInstLoc origin `thenM` \ loc -> - tcInstClassOp loc id [ty] `thenM` \ inst -> - extendLIE inst `thenM_` - returnM (instToId inst) + loc <- getInstLoc origin + inst <- tcInstClassOp loc id [ty] + extendLIE inst + return (instToId inst) -newMethodWithGivenTy orig id tys - = getInstLoc orig `thenM` \ loc -> - newMethod loc id tys `thenM` \ inst -> - extendLIE inst `thenM_` - returnM (instToId inst) +newMethodWithGivenTy orig id tys = do + loc <- getInstLoc orig + inst <- newMethod loc id tys + extendLIE inst + return (instToId inst) -------------------------------------------- -- tcInstClassOp, and newMethod do *not* drop the @@ -433,11 +433,10 @@ newMethodWithGivenTy orig id tys -- Hence the call to checkKind -- A worry: is this needed anywhere else? tcInstClassOp :: InstLoc -> Id -> [TcType] -> TcM Inst -tcInstClassOp inst_loc sel_id tys - = let +tcInstClassOp inst_loc sel_id tys = do + let (tyvars, _rho) = tcSplitForAllTys (idType sel_id) - in - zipWithM_ checkKind tyvars tys `thenM_` + zipWithM_ checkKind tyvars tys newMethod inst_loc sel_id tys checkKind :: TyVar -> TcType -> TcM () @@ -458,60 +457,29 @@ checkKind tv ty --------------------------- -newMethod inst_loc id tys - = newUnique `thenM` \ new_uniq -> +newMethod inst_loc id tys = do + new_uniq <- newUnique let (theta,tau) = tcSplitPhiTy (applyTys (idType id) tys) meth_id = mkUserLocal (mkMethodOcc (getOccName id)) new_uniq tau loc inst = Method {tci_id = meth_id, tci_oid = id, tci_tys = tys, tci_theta = theta, tci_loc = inst_loc} loc = instLocSpan inst_loc - in - returnM inst + + return inst \end{code} \begin{code} -shortCutIntLit :: Integer -> TcType -> Maybe (HsExpr TcId) -shortCutIntLit i ty - | isIntTy ty && inIntRange i -- Short cut for Int - = Just (HsLit (HsInt i)) - | isIntegerTy ty -- Short cut for Integer - = Just (HsLit (HsInteger i ty)) - | otherwise = Nothing - -shortCutFracLit :: Rational -> TcType -> Maybe (HsExpr TcId) -shortCutFracLit f ty - | isFloatTy ty - = Just (mk_lit floatDataCon (HsFloatPrim f)) - | isDoubleTy ty - = Just (mk_lit doubleDataCon (HsDoublePrim f)) - | otherwise = Nothing - where - mk_lit con lit = HsApp (nlHsVar (dataConWrapId con)) (nlHsLit lit) - -shortCutStringLit :: FastString -> TcType -> Maybe (HsExpr TcId) -shortCutStringLit s ty - | isStringTy ty -- Short cut for String - = Just (HsLit (HsString s)) - | otherwise = Nothing - -mkIntegerLit :: Integer -> TcM (LHsExpr TcId) -mkIntegerLit i - = tcMetaTy integerTyConName `thenM` \ integer_ty -> - getSrcSpanM `thenM` \ span -> - returnM (L span $ HsLit (HsInteger i integer_ty)) - -mkRatLit :: Rational -> TcM (LHsExpr TcId) -mkRatLit r - = tcMetaTy rationalTyConName `thenM` \ rat_ty -> - getSrcSpanM `thenM` \ span -> - returnM (L span $ HsLit (HsRat r rat_ty)) - -mkStrLit :: FastString -> TcM (LHsExpr TcId) -mkStrLit s - = --tcMetaTy stringTyConName `thenM` \ string_ty -> - getSrcSpanM `thenM` \ span -> - returnM (L span $ HsLit (HsString s)) +mkOverLit :: OverLitVal -> TcM HsLit +mkOverLit (HsIntegral i) + = do { integer_ty <- tcMetaTy integerTyConName + ; return (HsInteger i integer_ty) } + +mkOverLit (HsFractional r) + = do { rat_ty <- tcMetaTy rationalTyConName + ; return (HsRat r rat_ty) } + +mkOverLit (HsIsString s) = return (HsString s) isHsVar :: HsExpr Name -> Name -> Bool isHsVar (HsVar f) g = f==g @@ -529,24 +497,24 @@ Zonking makes sure that the instance types are fully zonked. \begin{code} zonkInst :: Inst -> TcM Inst -zonkInst dict@(Dict { tci_pred = pred}) - = zonkTcPredType pred `thenM` \ new_pred -> - returnM (dict {tci_pred = new_pred}) +zonkInst dict@(Dict { tci_pred = pred}) = do + new_pred <- zonkTcPredType pred + return (dict {tci_pred = new_pred}) -zonkInst meth@(Method {tci_oid = id, tci_tys = tys, tci_theta = theta}) - = zonkId id `thenM` \ new_id -> +zonkInst meth@(Method {tci_oid = id, tci_tys = tys, tci_theta = theta}) = do + new_id <- zonkId id -- Essential to zonk the id in case it's a local variable -- Can't use zonkIdOcc because the id might itself be -- an InstId, in which case it won't be in scope - zonkTcTypes tys `thenM` \ new_tys -> - zonkTcThetaType theta `thenM` \ new_theta -> - returnM (meth { tci_oid = new_id, tci_tys = new_tys, tci_theta = new_theta }) + new_tys <- zonkTcTypes tys + new_theta <- zonkTcThetaType theta + return (meth { tci_oid = new_id, tci_tys = new_tys, tci_theta = new_theta }) -- No need to zonk the tci_id -zonkInst lit@(LitInst {tci_ty = ty}) - = zonkTcType ty `thenM` \ new_ty -> - returnM (lit {tci_ty = new_ty}) +zonkInst lit@(LitInst {tci_ty = ty}) = do + new_ty <- zonkTcType ty + return (lit {tci_ty = new_ty}) zonkInst implic@(ImplicInst {}) = ASSERT( all isImmutableTyVar (tci_tyvars implic) ) @@ -563,7 +531,7 @@ zonkInst eqinst@(EqInst {tci_left = ty1, tci_right = ty2}) ; return (eqinst {tci_co = co', tci_left= ty1', tci_right = ty2' }) } -zonkInsts insts = mappM zonkInst insts +zonkInsts insts = mapM zonkInst insts \end{code} @@ -602,12 +570,14 @@ pprInst i@(EqInst {tci_left = ty1, tci_right = ty2, tci_co = co}) = eitherEqInst i (\covar -> text "Wanted" <+> ppr (TyVarTy covar) <+> dcolon <+> ppr (EqPred ty1 ty2)) (\co -> text "Given" <+> ppr co <+> dcolon <+> ppr (EqPred ty1 ty2)) -pprInst inst = ppr (instName inst) <+> dcolon - <+> (braces (ppr (instType inst)) $$ - ifPprDebug implic_stuff) +pprInst inst = ppr name <> braces (pprUnique (getUnique name)) <+> dcolon + <+> braces (ppr (instType inst) <> implicWantedEqs) where - implic_stuff | isImplicInst inst = ppr (tci_reft inst) - | otherwise = empty + name = instName inst + implicWantedEqs + | isImplicInst inst = text " &" <+> + ppr (filter isEqInst (tci_wanted inst)) + | otherwise = empty pprInstInFull inst@(EqInst {}) = pprInst inst pprInstInFull inst = sep [quotes (pprInst inst), nest 2 (pprInstArising inst)] @@ -725,11 +695,11 @@ traceDFuns ispecs funDepErr ispec ispecs = addDictLoc ispec $ - addErr (hang (ptext SLIT("Functional dependencies conflict between instance declarations:")) + addErr (hang (ptext (sLit "Functional dependencies conflict between instance declarations:")) 2 (pprInstances (ispec:ispecs))) dupInstErr ispec dup_ispec = addDictLoc ispec $ - addErr (hang (ptext SLIT("Duplicate instance declarations:")) + addErr (hang (ptext (sLit "Duplicate instance declarations:")) 2 (pprInstances [ispec, dup_ispec])) addDictLoc ispec thing_inside @@ -777,41 +747,27 @@ lookupSimpleInst (Method {tci_oid = id, tci_tys = tys, tci_theta = theta, tci_lo -- [Same shortcut as in newOverloadedLit, but we -- may have done some unification by now] -lookupSimpleInst (LitInst {tci_lit = HsIntegral i from_integer_name _, tci_ty = ty, tci_loc = loc}) - | Just expr <- shortCutIntLit i ty - = returnM (GenInst [] (noLoc expr)) - | otherwise - = ASSERT( from_integer_name `isHsVar` fromIntegerName ) -- A LitInst invariant - tcLookupId fromIntegerName `thenM` \ from_integer -> - tcInstClassOp loc from_integer [ty] `thenM` \ method_inst -> - mkIntegerLit i `thenM` \ integer_lit -> - returnM (GenInst [method_inst] - (mkHsApp (L (instLocSpan loc) - (HsVar (instToId method_inst))) integer_lit)) - -lookupSimpleInst (LitInst {tci_lit = HsFractional f from_rat_name _, tci_ty = ty, tci_loc = loc}) - | Just expr <- shortCutFracLit f ty - = returnM (GenInst [] (noLoc expr)) +lookupSimpleInst (LitInst { tci_lit = lit@OverLit { ol_val = lit_val + , ol_rebindable = rebindable } + , tci_ty = ty, tci_loc = iloc}) +#ifdef DEBUG + | rebindable = panic "lookupSimpleInst" -- A LitInst invariant +#endif + | Just witness <- shortCutLit lit_val ty + = do { let lit' = lit { ol_witness = witness, ol_type = ty } + ; return (GenInst [] (L loc (HsOverLit lit'))) } | otherwise - = ASSERT( from_rat_name `isHsVar` fromRationalName ) -- A LitInst invariant - tcLookupId fromRationalName `thenM` \ from_rational -> - tcInstClassOp loc from_rational [ty] `thenM` \ method_inst -> - mkRatLit f `thenM` \ rat_lit -> - returnM (GenInst [method_inst] (mkHsApp (L (instLocSpan loc) - (HsVar (instToId method_inst))) rat_lit)) - -lookupSimpleInst (LitInst {tci_lit = HsIsString s from_string_name _, tci_ty = ty, tci_loc = loc}) - | Just expr <- shortCutStringLit s ty - = returnM (GenInst [] (noLoc expr)) - | otherwise - = ASSERT( from_string_name `isHsVar` fromStringName ) -- A LitInst invariant - tcLookupId fromStringName `thenM` \ from_string -> - tcInstClassOp loc from_string [ty] `thenM` \ method_inst -> - mkStrLit s `thenM` \ string_lit -> - returnM (GenInst [method_inst] - (mkHsApp (L (instLocSpan loc) - (HsVar (instToId method_inst))) string_lit)) + = do { hs_lit <- mkOverLit lit_val + ; from_thing <- tcLookupId (hsOverLitName lit_val) + -- Not rebindable, so hsOverLitName is the right thing + ; method_inst <- tcInstClassOp iloc from_thing [ty] + ; let witness = HsApp (L loc (HsVar (instToId method_inst))) + (L loc (HsLit hs_lit)) + lit' = lit { ol_witness = witness, ol_type = ty } + ; return (GenInst [method_inst] (L loc (HsOverLit lit'))) } + where + loc = instLocSpan iloc --------------------- Dictionaries ------------------------ lookupSimpleInst (Dict {tci_pred = pred, tci_loc = loc}) @@ -821,7 +777,7 @@ lookupSimpleInst (Dict {tci_pred = pred, tci_loc = loc}) Just (dfun_id, mb_inst_tys) -> do { use_stage <- getStage - ; checkWellStaged (ptext SLIT("instance for") <+> quotes (ppr pred)) + ; checkWellStaged (ptext (sLit "instance for") <+> quotes (ppr pred)) (topIdLvl dfun_id) use_stage -- It's possible that not all the tyvars are in @@ -832,17 +788,17 @@ lookupSimpleInst (Dict {tci_pred = pred, tci_loc = loc}) ; let inst_tv (Left tv) = do { tv' <- tcInstTyVar tv; return (mkTyVarTy tv') } inst_tv (Right ty) = return ty - ; tys <- mappM inst_tv mb_inst_tys + ; tys <- mapM inst_tv mb_inst_tys ; let (theta, _) = tcSplitPhiTy (applyTys (idType dfun_id) tys) src_loc = instLocSpan loc dfun = HsVar dfun_id ; if null theta then - returnM (GenInst [] (L src_loc $ HsWrap (mkWpTyApps tys) dfun)) + return (GenInst [] (L src_loc $ HsWrap (mkWpTyApps tys) dfun)) else do { (dict_app, dicts) <- getLIE $ instCallDicts loc theta -- !!! ; let co_fn = dict_app <.> mkWpTyApps tys - ; returnM (GenInst dicts (L src_loc $ HsWrap co_fn dfun)) + ; return (GenInst dicts (L src_loc $ HsWrap co_fn dfun)) }}}} --------------- @@ -938,36 +894,36 @@ tcSyntaxName :: InstOrigin tcSyntaxName orig ty (std_nm, HsVar user_nm) | std_nm == user_nm - = newMethodFromName orig ty std_nm `thenM` \ id -> - returnM (std_nm, HsVar id) + = do id <- newMethodFromName orig ty std_nm + return (std_nm, HsVar id) -tcSyntaxName orig ty (std_nm, user_nm_expr) - = tcLookupId std_nm `thenM` \ std_id -> +tcSyntaxName orig ty (std_nm, user_nm_expr) = do + std_id <- tcLookupId std_nm let -- C.f. newMethodAtLoc ([tv], _, tau) = tcSplitSigmaTy (idType std_id) sigma1 = substTyWith [tv] [ty] tau -- Actually, the "tau-type" might be a sigma-type in the -- case of locally-polymorphic methods. - in - addErrCtxtM (syntaxNameCtxt user_nm_expr orig sigma1) $ + + addErrCtxtM (syntaxNameCtxt user_nm_expr orig sigma1) $ do -- Check that the user-supplied thing has the -- same type as the standard one. -- Tiresome jiggling because tcCheckSigma takes a located expression - getSrcSpanM `thenM` \ span -> - tcPolyExpr (L span user_nm_expr) sigma1 `thenM` \ expr -> - returnM (std_nm, unLoc expr) + span <- getSrcSpanM + expr <- tcPolyExpr (L span user_nm_expr) sigma1 + return (std_nm, unLoc expr) -syntaxNameCtxt name orig ty tidy_env - = getInstLoc orig `thenM` \ inst_loc -> +syntaxNameCtxt name orig ty tidy_env = do + inst_loc <- getInstLoc orig let - msg = vcat [ptext SLIT("When checking that") <+> quotes (ppr name) <+> - ptext SLIT("(needed by a syntactic construct)"), - nest 2 (ptext SLIT("has the required type:") <+> ppr (tidyType tidy_env ty)), - nest 2 (ptext SLIT("arising from") <+> pprInstLoc inst_loc)] - in - returnM (tidy_env, msg) + msg = vcat [ptext (sLit "When checking that") <+> quotes (ppr name) <+> + ptext (sLit "(needed by a syntactic construct)"), + nest 2 (ptext (sLit "has the required type:") <+> ppr (tidyType tidy_env ty)), + nest 2 (ptext (sLit "arising from") <+> pprInstLoc inst_loc)] + + return (tidy_env, msg) \end{code} %************************************************************************