X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FInst.lhs;h=1e99572c5e8b809c5cf3a70a23c463d3b3fc4443;hb=7bb069508f094825ca136ed97606651f3e093123;hp=fdef8c99097996fd939af4e82b543f774d221c29;hpb=672a54bb7c5c10cb2e18a975c717e4b2892b45b5;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/Inst.lhs b/ghc/compiler/typecheck/Inst.lhs index fdef8c9..1e99572 100644 --- a/ghc/compiler/typecheck/Inst.lhs +++ b/ghc/compiler/typecheck/Inst.lhs @@ -1,76 +1,94 @@ % -% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996 +% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % \section[Inst]{The @Inst@ type: dictionaries or method instances} \begin{code} -module Inst ( - LIE, emptyLIE, unitLIE, plusLIE, consLIE, zonkLIE, plusLIEs, mkLIE, - pprInsts, pprInstsInFull, +module Inst ( + LIE, emptyLIE, unitLIE, plusLIE, consLIE, zonkLIE, + plusLIEs, mkLIE, isEmptyLIE, lieToList, listToLIE, - Inst, OverloadedLit(..), pprInst, + Inst, OverloadedLit(..), + pprInst, pprInsts, pprInstsInFull, tidyInst, tidyInsts, - InstanceMapper, - - newDictFromOld, newDicts, newDictsAtLoc, + newDictFromOld, newDicts, newClassDicts, newDictsAtLoc, newMethod, newMethodWithGivenTy, newOverloadedLit, + newIPDict, instOverloadedFun, + instantiateFdClassTys, instFunDeps, instFunDepsOfTheta, + newFunDepFromDict, - tyVarsOfInst, instLoc, getDictClassTys, + tyVarsOfInst, tyVarsOfInsts, tyVarsOfLIE, instLoc, getDictClassTys, + getDictPred_maybe, getMethodTheta_maybe, + getFunDeps, getFunDepsOfLIE, + getIPs, getIPsOfLIE, + getAllFunDeps, getAllFunDepsOfLIE, lookupInst, lookupSimpleInst, LookupInstResult(..), - isDict, isTyVarDict, isStdClassTyVarDict, isMethodFor, + isDict, isClassDict, isMethod, + isTyVarDict, isStdClassTyVarDict, isMethodFor, notFunDep, instBindingRequired, instCanBeGeneralised, - zonkInst, instToId, + zonkInst, zonkInsts, zonkFunDeps, zonkTvFunDeps, + instToId, instToIdBndr, ipToId, - InstOrigin(..), pprOrigin + InstOrigin(..), InstLoc, pprInstLoc ) where #include "HsVersions.h" -import CmdLineOpts ( opt_AllowOverlappingInstances ) -import HsSyn ( HsLit(..), HsExpr(..), MonoBinds ) -import RnHsSyn ( RenamedArithSeqInfo, RenamedHsExpr ) -import TcHsSyn ( TcExpr, TcIdOcc(..), TcIdBndr, - mkHsTyApp, mkHsDictApp, tcIdTyVars, zonkTcId +import HsSyn ( HsLit(..), HsExpr(..) ) +import RnHsSyn ( RenamedArithSeqInfo, RenamedHsExpr, RenamedPat ) +import TcHsSyn ( TcExpr, TcId, + mkHsTyApp, mkHsDictApp, mkHsConApp, zonkId ) import TcMonad -import TcEnv ( tcLookupGlobalValueByKey, tcLookupTyConByKey ) +import TcEnv ( TcIdSet, InstEnv, tcGetInstEnv, lookupInstEnv, InstLookupResult(..), + tcLookupValueByKey, tcLookupTyConByKey + ) import TcType ( TcThetaType, - TcType, TcTauType, TcMaybe, TcTyVarSet, - tcInstType, zonkTcType, zonkTcTypes, tcSplitForAllTy, + TcType, TcTauType, TcTyVarSet, + zonkTcTyVars, zonkTcType, zonkTcTypes, zonkTcThetaType ) -import Bag ( emptyBag, unitBag, unionBags, unionManyBags, - listToBag, consBag, Bag ) -import Class ( classInstEnv, - Class, ClassInstEnv - ) -import MkId ( mkUserLocal, mkSysLocal ) -import Id ( Id, idType, mkId, - GenIdSet, elementOfIdSet - ) +import Bag +import Class ( Class, FunDep ) +import FunDeps ( instantiateFdClassTys ) +import Id ( Id, idFreeTyVars, idType, mkUserLocal, mkSysLocal ) import PrelInfo ( isStandardClass, isCcallishClass, isNoDictClass ) -import Name ( OccName(..), Name, occNameString, getOccName ) -import PprType ( TyCon, pprConstraint ) -import SpecEnv ( SpecEnv, lookupSpecEnv ) +import Name ( OccName, Name, mkDictOcc, mkMethodOcc, mkIPOcc, + getOccName, nameUnique ) +import PprType ( pprPred ) import SrcLoc ( SrcLoc ) -import Type ( Type, ThetaType, instantiateTy, instantiateThetaTy, - isTyVarTy, mkDictTy, splitForAllTys, splitSigmaTy, - splitRhoTy, tyVarsOfType, tyVarsOfTypes, - mkSynTy +import Type ( Type, PredType(..), ThetaType, + mkTyVarTy, isTyVarTy, mkDictTy, mkPredTy, + splitForAllTys, splitSigmaTy, + splitRhoTy, tyVarsOfType, tyVarsOfTypes, tyVarsOfPred, + mkSynTy, tidyOpenType, tidyOpenTypes ) -import TyVar ( zipTyVarEnv, lookupTyVarEnv, unionTyVarSets ) +import Subst ( emptyInScopeSet, mkSubst, + substTy, substClasses, mkTyVarSubst, mkTopTyVarSubst + ) +import TyCon ( TyCon ) +import Literal ( inIntRange ) +import Var ( TyVar ) +import VarEnv ( lookupVarEnv, TidyEnv, + lookupSubstEnv, SubstResult(..) + ) +import VarSet ( elemVarSet, emptyVarSet, unionVarSet ) import TysPrim ( intPrimTy, floatPrimTy, doublePrimTy ) -import TysWiredIn ( intDataCon, integerTy, isIntTy, isIntegerTy, inIntRange, - floatDataCon, isFloatTy, - doubleDataCon, isDoubleTy ) +import TysWiredIn ( intDataCon, isIntTy, + floatDataCon, isFloatTy, + doubleDataCon, isDoubleTy, + integerTy, isIntegerTy, + voidTy + ) import Unique ( fromRationalClassOpKey, rationalTyConKey, fromIntClassOpKey, fromIntegerClassOpKey, Unique ) -import Maybes ( MaybeErr, expectJust ) -import Util ( thenCmp, zipWithEqual ) +import Maybes ( expectJust ) +import Maybe ( catMaybes ) +import Util ( thenCmp, zipWithEqual, mapAccumL ) import Outputable \end{code} @@ -81,26 +99,29 @@ import Outputable %************************************************************************ \begin{code} -type LIE s = Bag (Inst s) +type LIE = Bag Inst +isEmptyLIE = isEmptyBag emptyLIE = emptyBag unitLIE inst = unitBag inst mkLIE insts = listToBag insts plusLIE lie1 lie2 = lie1 `unionBags` lie2 consLIE inst lie = inst `consBag` lie plusLIEs lies = unionManyBags lies +lieToList = bagToList +listToLIE = listToBag -zonkLIE :: LIE s -> NF_TcM s (LIE s) +zonkLIE :: LIE -> NF_TcM s LIE zonkLIE lie = mapBagNF_Tc zonkInst lie -pprInsts :: [Inst s] -> SDoc -pprInsts insts = parens (hsep (punctuate comma (map pprInst insts))) +pprInsts :: [Inst] -> SDoc +pprInsts insts = parens (sep (punctuate comma (map pprInst insts))) pprInstsInFull insts = vcat (map go insts) where - go inst = quotes (ppr inst) <+> pprOrigin inst + go inst = quotes (ppr inst) <+> pprInstLoc (instLoc inst) \end{code} %************************************************************************ @@ -118,35 +139,32 @@ type Int, represented by Method 34 doubleId [Int] origin \begin{code} -data Inst s +data Inst = Dict Unique - Class -- The type of the dict is (c ts), where - [TcType s] -- c is the class and ts the types; - (InstOrigin s) - SrcLoc + TcPredType + InstLoc | Method Unique - (TcIdOcc s) -- The overloaded function + TcId -- The overloaded function -- This function will be a global, local, or ClassOpId; -- inside instance decls (only) it can also be an InstId! -- The id needn't be completely polymorphic. -- You'll probably find its name (for documentation purposes) -- inside the InstOrigin - [TcType s] -- The types to which its polymorphic tyvars + [TcType] -- The types to which its polymorphic tyvars -- should be instantiated. -- These types must saturate the Id's foralls. - (TcThetaType s) -- The (types of the) dictionaries to which the function + TcThetaType -- The (types of the) dictionaries to which the function -- must be applied to get the method - (TcTauType s) -- The type of the method + TcTauType -- The type of the method - (InstOrigin s) - SrcLoc + InstLoc -- INVARIANT: in (Method u f tys theta tau loc) -- type of (f tys dicts(from theta)) = tau @@ -154,9 +172,14 @@ data Inst s | LitInst Unique OverloadedLit - (TcType s) -- The type at which the literal is used - (InstOrigin s) -- Always a literal; but more convenient to carry this around - SrcLoc + TcType -- The type at which the literal is used + InstLoc + + | FunDep + Unique + Class -- the class from which this arises + [FunDep TcType] + InstLoc data OverloadedLit = OverloadedIntegral Integer -- The number @@ -170,31 +193,27 @@ unique. This allows the context-reduction mechanism to use standard finite maps to do their stuff. \begin{code} -instance Ord (Inst s) where +instance Ord Inst where compare = cmpInst -instance Eq (Inst s) where +instance Eq Inst where (==) i1 i2 = case i1 `cmpInst` i2 of EQ -> True other -> False -cmpInst (Dict _ clas1 tys1 _ _) (Dict _ clas2 tys2 _ _) - = (clas1 `compare` clas2) `thenCmp` (tys1 `compare` tys2) -cmpInst (Dict _ _ _ _ _) other - = LT +cmpInst (Dict _ pred1 _) (Dict _ pred2 _) = (pred1 `compare` pred2) +cmpInst (Dict _ _ _) other = LT +cmpInst (Method _ _ _ _ _ _) (Dict _ _ _) = GT +cmpInst (Method _ id1 tys1 _ _ _) (Method _ id2 tys2 _ _ _) = (id1 `compare` id2) `thenCmp` (tys1 `compare` tys2) +cmpInst (Method _ _ _ _ _ _) other = LT -cmpInst (Method _ _ _ _ _ _ _) (Dict _ _ _ _ _) - = GT -cmpInst (Method _ id1 tys1 _ _ _ _) (Method _ id2 tys2 _ _ _ _) - = (id1 `compare` id2) `thenCmp` (tys1 `compare` tys2) -cmpInst (Method _ _ _ _ _ _ _) other - = LT +cmpInst (LitInst _ lit1 ty1 _) (LitInst _ lit2 ty2 _) = (lit1 `cmpOverLit` lit2) `thenCmp` (ty1 `compare` ty2) +cmpInst (LitInst _ _ _ _) (FunDep _ _ _ _) = LT +cmpInst (LitInst _ _ _ _) other = GT -cmpInst (LitInst _ lit1 ty1 _ _) (LitInst _ lit2 ty2 _ _) - = (lit1 `cmpOverLit` lit2) `thenCmp` (ty1 `compare` ty2) -cmpInst (LitInst _ _ _ _ _) other - = GT +cmpInst (FunDep _ clas1 fds1 _) (FunDep _ clas2 fds2 _) = (clas1 `compare` clas2) `thenCmp` (fds1 `compare` fds2) +cmpInst (FunDep _ _ _ _) other = GT cmpOverLit (OverloadedIntegral i1) (OverloadedIntegral i2) = i1 `compare` i2 cmpOverLit (OverloadedFractional f1) (OverloadedFractional f2) = f1 `compare` f2 @@ -206,43 +225,89 @@ cmpOverLit (OverloadedFractional _) (OverloadedIntegral _) = GT Selection ~~~~~~~~~ \begin{code} -instOrigin (Dict u clas tys origin loc) = origin -instOrigin (Method u clas ty _ _ origin loc) = origin -instOrigin (LitInst u lit ty origin loc) = origin +instLoc (Dict u pred loc) = loc +instLoc (Method u _ _ _ _ loc) = loc +instLoc (LitInst u lit ty loc) = loc +instLoc (FunDep _ _ _ loc) = loc + +getDictPred_maybe (Dict _ p _) = Just p +getDictPred_maybe _ = Nothing + +getMethodTheta_maybe (Method _ _ _ theta _ _) = Just theta +getMethodTheta_maybe _ = Nothing + +getDictClassTys (Dict u (Class clas tys) _) = (clas, tys) + +getFunDeps (FunDep _ clas fds _) = Just (clas, fds) +getFunDeps _ = Nothing + +getFunDepsOfLIE lie = catMaybes (map getFunDeps (lieToList lie)) + +getIPsOfPred (IParam n ty) = [(n, ty)] +getIPsOfPred _ = [] +getIPsOfTheta theta = concatMap getIPsOfPred theta -instLoc (Dict u clas tys origin loc) = loc -instLoc (Method u clas ty _ _ origin loc) = loc -instLoc (LitInst u lit ty origin loc) = loc +getIPs (Dict u (IParam n ty) loc) = [(n, ty)] +getIPs (Method u id _ theta t loc) = getIPsOfTheta theta +getIPs _ = [] -getDictClassTys (Dict u clas tys _ _) = (clas, tys) +getIPsOfLIE lie = concatMap getIPs (lieToList lie) -tyVarsOfInst :: Inst s -> TcTyVarSet s -tyVarsOfInst (Dict _ _ tys _ _) = tyVarsOfTypes tys -tyVarsOfInst (Method _ id tys _ _ _ _) = tyVarsOfTypes tys `unionTyVarSets` tcIdTyVars id - -- The id might not be a RealId; in the case of +getAllFunDeps (FunDep _ clas fds _) = fds +getAllFunDeps inst = map (\(n,ty) -> ([], [ty])) (getIPs inst) + +getAllFunDepsOfLIE lie = concat (map getAllFunDeps (lieToList lie)) + +tyVarsOfInst :: Inst -> TcTyVarSet +tyVarsOfInst (Dict _ pred _) = tyVarsOfPred pred +tyVarsOfInst (Method _ id tys _ _ _) = tyVarsOfTypes tys `unionVarSet` idFreeTyVars id + -- The id might have free type variables; in the case of -- locally-overloaded class methods, for example -tyVarsOfInst (LitInst _ _ ty _ _) = tyVarsOfType ty +tyVarsOfInst (LitInst _ _ ty _) = tyVarsOfType ty +tyVarsOfInst (FunDep _ _ fds _) + = foldr unionVarSet emptyVarSet (map tyVarsOfFd fds) + where tyVarsOfFd (ts1, ts2) = + tyVarsOfTypes ts1 `unionVarSet` tyVarsOfTypes ts2 + +tyVarsOfInsts insts + = foldr unionVarSet emptyVarSet (map tyVarsOfInst insts) + +tyVarsOfLIE lie + = foldr unionVarSet emptyVarSet (map tyVarsOfInst insts) + where insts = lieToList lie \end{code} Predicates ~~~~~~~~~~ \begin{code} -isDict :: Inst s -> Bool -isDict (Dict _ _ _ _ _) = True -isDict other = False - -isMethodFor :: GenIdSet (TcType s) -> Inst s -> Bool -isMethodFor ids (Method uniq (TcId id) tys _ _ orig loc) - = id `elementOfIdSet` ids -isMethodFor ids inst - = False +isDict :: Inst -> Bool +isDict (Dict _ _ _) = True +isDict other = False + +isClassDict :: Inst -> Bool +isClassDict (Dict _ (Class _ _) _) = True +isClassDict other = False -isTyVarDict :: Inst s -> Bool -isTyVarDict (Dict _ _ tys _ _) = all isTyVarTy tys -isTyVarDict other = False +isMethod :: Inst -> Bool +isMethod (Method _ _ _ _ _ _) = True +isMethod other = False -isStdClassTyVarDict (Dict _ clas [ty] _ _) = isStandardClass clas && isTyVarTy ty -isStdClassTyVarDict other = False +isMethodFor :: TcIdSet -> Inst -> Bool +isMethodFor ids (Method uniq id tys _ _ loc) = id `elemVarSet` ids +isMethodFor ids inst = False + +isTyVarDict :: Inst -> Bool +isTyVarDict (Dict _ (Class _ tys) _) = all isTyVarTy tys +isTyVarDict other = False + +isStdClassTyVarDict (Dict _ (Class clas [ty]) _) + = isStandardClass clas && isTyVarTy ty +isStdClassTyVarDict other + = False + +notFunDep :: Inst -> Bool +notFunDep (FunDep _ _ _ _) = False +notFunDep other = True \end{code} Two predicates which deal with the case where class constraints don't @@ -251,13 +316,14 @@ must be witnessed by an actual binding; the second tells whether an @Inst@ can be generalised over. \begin{code} -instBindingRequired :: Inst s -> Bool -instBindingRequired (Dict _ clas _ _ _) = not (isNoDictClass clas) -instBindingRequired other = True - -instCanBeGeneralised :: Inst s -> Bool -instCanBeGeneralised (Dict _ clas _ _ _) = not (isCcallishClass clas) -instCanBeGeneralised other = True +instBindingRequired :: Inst -> Bool +instBindingRequired (Dict _ (Class clas _) _) = not (isNoDictClass clas) +instBindingRequired (Dict _ (IParam _ _) _) = False +instBindingRequired other = True + +instCanBeGeneralised :: Inst -> Bool +instCanBeGeneralised (Dict _ (Class clas _) _) = not (isCcallishClass clas) +instCanBeGeneralised other = True \end{code} @@ -265,78 +331,94 @@ Construction ~~~~~~~~~~~~ \begin{code} -newDicts :: InstOrigin s - -> TcThetaType s - -> NF_TcM s (LIE s, [TcIdOcc s]) +newDicts :: InstOrigin + -> TcThetaType + -> NF_TcM s (LIE, [TcId]) newDicts orig theta - = tcGetSrcLoc `thenNF_Tc` \ loc -> - newDictsAtLoc orig loc theta `thenNF_Tc` \ (dicts, ids) -> + = tcGetInstLoc orig `thenNF_Tc` \ loc -> + newDictsAtLoc loc theta `thenNF_Tc` \ (dicts, ids) -> returnNF_Tc (listToBag dicts, ids) +newClassDicts :: InstOrigin + -> [(Class,[TcType])] + -> NF_TcM s (LIE, [TcId]) +newClassDicts orig theta + = newDicts orig (map (uncurry Class) theta) + -- Local function, similar to newDicts, -- but with slightly different interface -newDictsAtLoc :: InstOrigin s - -> SrcLoc - -> TcThetaType s - -> NF_TcM s ([Inst s], [TcIdOcc s]) -newDictsAtLoc orig loc theta = +newDictsAtLoc :: InstLoc + -> TcThetaType + -> NF_TcM s ([Inst], [TcId]) +newDictsAtLoc loc theta = tcGetUniques (length theta) `thenNF_Tc` \ new_uniqs -> let - mk_dict u (clas, tys) = Dict u clas tys orig loc + mk_dict u pred = Dict u pred loc dicts = zipWithEqual "newDictsAtLoc" mk_dict new_uniqs theta in returnNF_Tc (dicts, map instToId dicts) -newDictFromOld :: Inst s -> Class -> [TcType s] -> NF_TcM s (Inst s) -newDictFromOld (Dict _ _ _ orig loc) clas tys +newDictFromOld :: Inst -> Class -> [TcType] -> NF_TcM s Inst +newDictFromOld (Dict _ _ loc) clas tys = tcGetUnique `thenNF_Tc` \ uniq -> - returnNF_Tc (Dict uniq clas tys orig loc) + returnNF_Tc (Dict uniq (Class clas tys) loc) -newMethod :: InstOrigin s - -> TcIdOcc s - -> [TcType s] - -> NF_TcM s (LIE s, TcIdOcc s) +newMethod :: InstOrigin + -> TcId + -> [TcType] + -> NF_TcM s (LIE, TcId) newMethod orig id tys = -- Get the Id type and instantiate it at the specified types - (case id of - RealId id -> let (tyvars, rho) = splitForAllTys (idType id) - in - ASSERT( length tyvars == length tys) - tcInstType (zipTyVarEnv tyvars tys) rho - - TcId id -> tcSplitForAllTy (idType id) `thenNF_Tc` \ (tyvars, rho) -> - returnNF_Tc (instantiateTy (zipTyVarEnv tyvars tys) rho) - ) `thenNF_Tc` \ rho_ty -> let - (theta, tau) = splitRhoTy rho_ty + (tyvars, rho) = splitForAllTys (idType id) + rho_ty = substTy (mkTyVarSubst tyvars tys) rho + (theta, tau) = splitRhoTy rho_ty in - -- Our friend does the rest - newMethodWithGivenTy orig id tys theta tau + newMethodWithGivenTy orig id tys theta tau `thenNF_Tc` \ meth_inst -> + returnNF_Tc (unitLIE meth_inst, instToId meth_inst) +instOverloadedFun orig v arg_tys theta tau +-- This is where we introduce new functional dependencies into the LIE + = newMethodWithGivenTy orig v arg_tys theta tau `thenNF_Tc` \ inst -> + instFunDeps orig theta `thenNF_Tc` \ fds -> + returnNF_Tc (instToId inst, mkLIE (inst : fds)) + +instFunDeps orig theta + = tcGetUnique `thenNF_Tc` \ uniq -> + tcGetInstLoc orig `thenNF_Tc` \ loc -> + let ifd (Class clas tys) = + let fds = instantiateFdClassTys clas tys in + if null fds then Nothing else Just (FunDep uniq clas fds loc) + ifd _ = Nothing + in returnNF_Tc (catMaybes (map ifd theta)) + +instFunDepsOfTheta theta + = let ifd (Class clas tys) = instantiateFdClassTys clas tys + ifd (IParam n ty) = [([], [ty])] + in concat (map ifd theta) newMethodWithGivenTy orig id tys theta tau - = tcGetSrcLoc `thenNF_Tc` \ loc -> - tcGetUnique `thenNF_Tc` \ new_uniq -> - let - meth_inst = Method new_uniq id tys theta tau orig loc - in - returnNF_Tc (unitLIE meth_inst, instToId meth_inst) + = tcGetInstLoc orig `thenNF_Tc` \ loc -> + newMethodWith id tys theta tau loc + +newMethodWith id tys theta tau loc + = tcGetUnique `thenNF_Tc` \ new_uniq -> + returnNF_Tc (Method new_uniq id tys theta tau loc) -newMethodAtLoc :: InstOrigin s -> SrcLoc - -> Id -> [TcType s] - -> NF_TcM s (Inst s, TcIdOcc s) -newMethodAtLoc orig loc real_id tys -- Local function, similar to newMethod but with +newMethodAtLoc :: InstLoc + -> Id -> [TcType] + -> NF_TcM s (Inst, TcId) +newMethodAtLoc loc real_id tys -- Local function, similar to newMethod but with -- slightly different interface = -- Get the Id type and instantiate it at the specified types - let - (tyvars,rho) = splitForAllTys (idType real_id) - in - tcInstType (zipTyVarEnv tyvars tys) rho `thenNF_Tc` \ rho_ty -> tcGetUnique `thenNF_Tc` \ new_uniq -> let - (theta, tau) = splitRhoTy rho_ty - meth_inst = Method new_uniq (RealId real_id) tys theta tau orig loc + (tyvars,rho) = splitForAllTys (idType real_id) + rho_ty = ASSERT( length tyvars == length tys ) + substTy (mkTopTyVarSubst tyvars tys) rho + (theta, tau) = splitRhoTy rho_ty + meth_inst = Method new_uniq real_id tys theta tau loc in returnNF_Tc (meth_inst, instToId meth_inst) \end{code} @@ -347,10 +429,10 @@ temporarily generating overloaded literals, but it won't catch all cases (the rest are caught in lookupInst). \begin{code} -newOverloadedLit :: InstOrigin s +newOverloadedLit :: InstOrigin -> OverloadedLit - -> TcType s - -> NF_TcM s (TcExpr s, LIE s) + -> TcType + -> NF_TcM s (TcExpr, LIE) newOverloadedLit orig (OverloadedIntegral i) ty | isIntTy ty && inIntRange i -- Short cut for Int = returnNF_Tc (int_lit, emptyLIE) @@ -361,30 +443,55 @@ newOverloadedLit orig (OverloadedIntegral i) ty where intprim_lit = HsLitOut (HsIntPrim i) intPrimTy integer_lit = HsLitOut (HsInt i) integerTy - int_lit = HsApp (HsVar (RealId intDataCon)) intprim_lit - + int_lit = mkHsConApp intDataCon [] [intprim_lit] + newOverloadedLit orig lit ty -- The general case - = tcGetSrcLoc `thenNF_Tc` \ loc -> + = tcGetInstLoc orig `thenNF_Tc` \ loc -> tcGetUnique `thenNF_Tc` \ new_uniq -> let - lit_inst = LitInst new_uniq lit ty orig loc + lit_inst = LitInst new_uniq lit ty loc in returnNF_Tc (HsVar (instToId lit_inst), unitLIE lit_inst) \end{code} +\begin{code} +newFunDepFromDict dict + = tcGetUnique `thenNF_Tc` \ uniq -> + let (clas, tys) = getDictClassTys dict + fds = instantiateFdClassTys clas tys + inst = FunDep uniq clas fds (instLoc dict) + in + if null fds then returnNF_Tc Nothing else returnNF_Tc (Just inst) +\end{code} \begin{code} -instToId :: Inst s -> TcIdOcc s -instToId (Dict u clas ty orig loc) - = TcId (mkUserLocal occ u (mkDictTy clas ty) loc) - where - occ = VarOcc (SLIT("d.") _APPEND_ (occNameString (getOccName clas))) +newIPDict name ty loc + = tcGetUnique `thenNF_Tc` \ new_uniq -> + let d = Dict new_uniq (IParam name ty) loc in + returnNF_Tc d +\end{code} + +\begin{code} +instToId :: Inst -> TcId +instToId inst = instToIdBndr inst + +instToIdBndr :: Inst -> TcId +instToIdBndr (Dict u (Class clas tys) (_,loc,_)) + = mkUserLocal (mkDictOcc (getOccName clas)) u (mkDictTy clas tys) loc +instToIdBndr (Dict u (IParam n ty) (_,loc,_)) + = ipToId n ty loc -instToId (Method u id tys theta tau orig loc) - = TcId (mkUserLocal (getOccName id) u tau loc) - -instToId (LitInst u list ty orig loc) - = TcId (mkSysLocal SLIT("lit") u ty loc) +instToIdBndr (Method u id tys theta tau (_,loc,_)) + = mkUserLocal (mkMethodOcc (getOccName id)) u tau loc + +instToIdBndr (LitInst u list ty loc) + = mkSysLocal SLIT("lit") u ty + +instToIdBndr (FunDep u clas fds _) + = mkSysLocal SLIT("FunDep") u voidTy + +ipToId n ty loc + = mkUserLocal (mkIPOcc (getOccName n)) (nameUnique n) (mkPredTy (IParam n ty)) loc \end{code} @@ -395,22 +502,54 @@ but doesn't do the same for the Id in a Method. There's no need, and it's a lot of extra work. \begin{code} -zonkInst :: Inst s -> NF_TcM s (Inst s) -zonkInst (Dict u clas tys orig loc) - = zonkTcTypes tys `thenNF_Tc` \ new_tys -> - returnNF_Tc (Dict u clas new_tys orig loc) - -zonkInst (Method u id tys theta tau orig loc) - = zonkTcId id `thenNF_Tc` \ new_id -> - -- Essential to zonk the id in case it's a local variable +zonkPred :: TcPredType -> NF_TcM s TcPredType +zonkPred (Class clas tys) + = zonkTcTypes tys `thenNF_Tc` \ new_tys -> + returnNF_Tc (Class clas new_tys) +zonkPred (IParam n ty) + = zonkTcType ty `thenNF_Tc` \ new_ty -> + returnNF_Tc (IParam n new_ty) + +zonkInst :: Inst -> NF_TcM s Inst +zonkInst (Dict u pred loc) + = zonkPred pred `thenNF_Tc` \ new_pred -> + returnNF_Tc (Dict u new_pred loc) + +zonkInst (Method u id tys theta tau loc) + = zonkId id `thenNF_Tc` \ new_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 `thenNF_Tc` \ new_tys -> zonkTcThetaType theta `thenNF_Tc` \ new_theta -> zonkTcType tau `thenNF_Tc` \ new_tau -> - returnNF_Tc (Method u new_id new_tys new_theta new_tau orig loc) + returnNF_Tc (Method u new_id new_tys new_theta new_tau loc) -zonkInst (LitInst u lit ty orig loc) +zonkInst (LitInst u lit ty loc) = zonkTcType ty `thenNF_Tc` \ new_ty -> - returnNF_Tc (LitInst u lit new_ty orig loc) + returnNF_Tc (LitInst u lit new_ty loc) + +zonkInst (FunDep u clas fds loc) + = zonkFunDeps fds `thenNF_Tc` \ fds' -> + returnNF_Tc (FunDep u clas fds' loc) + +zonkPreds preds = mapNF_Tc zonkPred preds +zonkInsts insts = mapNF_Tc zonkInst insts + +zonkFunDeps fds = mapNF_Tc zonkFd fds + where + zonkFd (ts1, ts2) + = zonkTcTypes ts1 `thenNF_Tc` \ ts1' -> + zonkTcTypes ts2 `thenNF_Tc` \ ts2' -> + returnNF_Tc (ts1', ts2') + +zonkTvFunDeps fds = mapNF_Tc zonkFd fds + where + zonkFd (tvs1, tvs2) + = zonkTcTyVars tvs1 `thenNF_Tc` \ tvs1' -> + zonkTcTyVars tvs2 `thenNF_Tc` \ tvs2' -> + returnNF_Tc (tvs1', tvs2') \end{code} @@ -420,10 +559,10 @@ ToDo: improve these pretty-printing things. The ``origin'' is really only relevant in error messages. \begin{code} -instance Outputable (Inst s) where +instance Outputable Inst where ppr inst = pprInst inst -pprInst (LitInst u lit ty orig loc) +pprInst (LitInst u lit ty loc) = hsep [case lit of OverloadedIntegral i -> integer i OverloadedFractional f -> rational f, @@ -431,12 +570,50 @@ pprInst (LitInst u lit ty orig loc) ppr ty, show_uniq u] -pprInst (Dict u clas tys orig loc) = pprConstraint clas tys <+> show_uniq u +pprInst (Dict u pred loc) = pprPred pred <+> show_uniq u -pprInst (Method u id tys _ _ orig loc) +pprInst m@(Method u id tys theta tau loc) = hsep [ppr id, ptext SLIT("at"), - interppSP tys, - show_uniq u] + brackets (interppSP tys) {- , + ppr theta, ppr tau, + show_uniq u, + ppr (instToId m) -}] + +pprInst (FunDep _ clas fds loc) + = hsep [ppr clas, ppr fds] + +tidyPred :: TidyEnv -> TcPredType -> (TidyEnv, TcPredType) +tidyPred env (Class clas tys) + = (env', Class clas tys') + where + (env', tys') = tidyOpenTypes env tys +tidyPred env (IParam n ty) + = (env', IParam n ty') + where + (env', ty') = tidyOpenType env ty + +tidyInst :: TidyEnv -> Inst -> (TidyEnv, Inst) +tidyInst env (LitInst u lit ty loc) + = (env', LitInst u lit ty' loc) + where + (env', ty') = tidyOpenType env ty + +tidyInst env (Dict u pred loc) + = (env', Dict u pred' loc) + where + (env', pred') = tidyPred env pred + +tidyInst env (Method u id tys theta tau loc) + = (env', Method u id tys' theta tau loc) + -- Leave theta, tau alone cos we don't print them + where + (env', tys') = tidyOpenTypes env tys + +-- this case shouldn't arise... (we never print fundeps) +tidyInst env fd@(FunDep _ clas fds loc) + = (env, fd) + +tidyInsts env insts = mapAccumL tidyInst env insts show_uniq u = ifPprDebug (text "{-" <> ppr u <> text "-}") \end{code} @@ -449,68 +626,53 @@ show_uniq u = ifPprDebug (text "{-" <> ppr u <> text "-}") %************************************************************************ \begin{code} -type InstanceMapper = Class -> ClassInstEnv -\end{code} - -A @ClassInstEnv@ lives inside a class, and identifies all the instances -of that class. The @Id@ inside a ClassInstEnv mapping is the dfun for -that instance. - -There is an important consistency constraint between the @MatchEnv@s -in and the dfun @Id@s inside them: the free type variables of the -@Type@ key in the @MatchEnv@ must be a subset of the universally-quantified -type variables of the dfun. Thus, the @ClassInstEnv@ for @Eq@ might -contain the following entry: -@ - [a] ===> dfun_Eq_List :: forall a. Eq a => Eq [a] -@ -The "a" in the pattern must be one of the forall'd variables in -the dfun type. - -\begin{code} data LookupInstResult s = NoInstance - | SimpleInst (TcExpr s) -- Just a variable, type application, or literal - | GenInst [Inst s] (TcExpr s) -- The expression and its needed insts -lookupInst :: Inst s + | SimpleInst TcExpr -- Just a variable, type application, or literal + | GenInst [Inst] TcExpr -- The expression and its needed insts + +lookupInst :: Inst -> NF_TcM s (LookupInstResult s) -- Dictionaries -lookupInst dict@(Dict _ clas tys orig loc) - = case lookupSpecEnv (ppr clas) (classInstEnv clas) tys of +lookupInst dict@(Dict _ (Class clas tys) loc) + = tcGetInstEnv `thenNF_Tc` \ inst_env -> + case lookupInstEnv inst_env clas tys of - Just (tenv, dfun_id) + FoundInst tenv dfun_id -> let + subst = mkSubst (tyVarsOfTypes tys) tenv (tyvars, rho) = splitForAllTys (idType dfun_id) - ty_args = map (expectJust "Inst" . lookupTyVarEnv tenv) tyvars - -- tenv should bind all the tyvars - in - tcInstType tenv rho `thenNF_Tc` \ dfun_rho -> - let - (theta, tau) = splitRhoTy dfun_rho - ty_app = mkHsTyApp (HsVar (RealId dfun_id)) ty_args + ty_args = map subst_tv tyvars + dfun_rho = substTy subst rho + (theta, tau) = splitRhoTy dfun_rho + ty_app = mkHsTyApp (HsVar dfun_id) ty_args + subst_tv tv = case lookupSubstEnv tenv tv of + Just (DoneTy ty) -> ty + -- tenv should bind all the tyvars in if null theta then returnNF_Tc (SimpleInst ty_app) else - newDictsAtLoc orig loc theta `thenNF_Tc` \ (dicts, dict_ids) -> + newDictsAtLoc loc theta `thenNF_Tc` \ (dicts, dict_ids) -> let rhs = mkHsDictApp ty_app dict_ids in returnNF_Tc (GenInst dicts rhs) - - Nothing -> returnNF_Tc NoInstance + + other -> returnNF_Tc NoInstance +lookupInst dict@(Dict _ _ loc) = returnNF_Tc NoInstance -- Methods -lookupInst inst@(Method _ id tys theta _ orig loc) - = newDictsAtLoc orig loc theta `thenNF_Tc` \ (dicts, dict_ids) -> +lookupInst inst@(Method _ id tys theta _ loc) + = newDictsAtLoc loc theta `thenNF_Tc` \ (dicts, dict_ids) -> returnNF_Tc (GenInst dicts (mkHsDictApp (mkHsTyApp (HsVar id) tys) dict_ids)) -- Literals -lookupInst inst@(LitInst u (OverloadedIntegral i) ty orig loc) +lookupInst inst@(LitInst u (OverloadedIntegral i) ty loc) | isIntTy ty && in_int_range -- Short cut for Int = returnNF_Tc (GenInst [] int_lit) -- GenInst, not SimpleInst, because int_lit is actually a constructor application @@ -519,30 +681,30 @@ lookupInst inst@(LitInst u (OverloadedIntegral i) ty orig loc) = returnNF_Tc (GenInst [] integer_lit) | in_int_range -- It's overloaded but small enough to fit into an Int - = tcLookupGlobalValueByKey fromIntClassOpKey `thenNF_Tc` \ from_int -> - newMethodAtLoc orig loc from_int [ty] `thenNF_Tc` \ (method_inst, method_id) -> + = tcLookupValueByKey fromIntClassOpKey `thenNF_Tc` \ from_int -> + newMethodAtLoc loc from_int [ty] `thenNF_Tc` \ (method_inst, method_id) -> returnNF_Tc (GenInst [method_inst] (HsApp (HsVar method_id) int_lit)) | otherwise -- Alas, it is overloaded and a big literal! - = tcLookupGlobalValueByKey fromIntegerClassOpKey `thenNF_Tc` \ from_integer -> - newMethodAtLoc orig loc from_integer [ty] `thenNF_Tc` \ (method_inst, method_id) -> + = tcLookupValueByKey fromIntegerClassOpKey `thenNF_Tc` \ from_integer -> + newMethodAtLoc loc from_integer [ty] `thenNF_Tc` \ (method_inst, method_id) -> returnNF_Tc (GenInst [method_inst] (HsApp (HsVar method_id) integer_lit)) where in_int_range = inIntRange i intprim_lit = HsLitOut (HsIntPrim i) intPrimTy integer_lit = HsLitOut (HsInt i) integerTy - int_lit = HsApp (HsVar (RealId intDataCon)) intprim_lit + int_lit = mkHsConApp intDataCon [] [intprim_lit] -- similar idea for overloaded floating point literals: if the literal is -- *definitely* a float or a double, generate the real thing here. -- This is essential (see nofib/spectral/nucleic). -lookupInst inst@(LitInst u (OverloadedFractional f) ty orig loc) +lookupInst inst@(LitInst u (OverloadedFractional f) ty loc) | isFloatTy ty = returnNF_Tc (GenInst [] float_lit) | isDoubleTy ty = returnNF_Tc (GenInst [] double_lit) | otherwise - = tcLookupGlobalValueByKey fromRationalClassOpKey `thenNF_Tc` \ from_rational -> + = tcLookupValueByKey fromRationalClassOpKey `thenNF_Tc` \ from_rational -> -- The type Rational isn't wired in so we have to conjure it up tcLookupTyConByKey rationalTyConKey `thenNF_Tc` \ rational_tycon -> @@ -550,14 +712,18 @@ lookupInst inst@(LitInst u (OverloadedFractional f) ty orig loc) rational_ty = mkSynTy rational_tycon [] rational_lit = HsLitOut (HsFrac f) rational_ty in - newMethodAtLoc orig loc from_rational [ty] `thenNF_Tc` \ (method_inst, method_id) -> + newMethodAtLoc loc from_rational [ty] `thenNF_Tc` \ (method_inst, method_id) -> returnNF_Tc (GenInst [method_inst] (HsApp (HsVar method_id) rational_lit)) where floatprim_lit = HsLitOut (HsFloatPrim f) floatPrimTy - float_lit = HsApp (HsVar (RealId floatDataCon)) floatprim_lit + float_lit = mkHsConApp floatDataCon [] [floatprim_lit] doubleprim_lit = HsLitOut (HsDoublePrim f) doublePrimTy - double_lit = HsApp (HsVar (RealId doubleDataCon)) doubleprim_lit + double_lit = mkHsConApp doubleDataCon [] [doubleprim_lit] + +-- there are no `instances' of functional dependencies or implicit params + +lookupInst _ = returnNF_Tc NoInstance \end{code} @@ -567,120 +733,20 @@ appropriate dictionary if it exists. It is used only when resolving ambiguous dictionaries. \begin{code} -lookupSimpleInst :: ClassInstEnv - -> Class - -> [Type] -- Look up (c,t) - -> NF_TcM s (Maybe ThetaType) -- Here are the needed (c,t)s - -lookupSimpleInst class_inst_env clas tys - = case lookupSpecEnv (ppr clas) class_inst_env tys of - Nothing -> returnNF_Tc Nothing - - Just (tenv, dfun) - -> returnNF_Tc (Just (instantiateThetaTy tenv theta)) +lookupSimpleInst :: Class + -> [Type] -- Look up (c,t) + -> NF_TcM s (Maybe [(Class,[Type])]) -- Here are the needed (c,t)s + +lookupSimpleInst clas tys + = tcGetInstEnv `thenNF_Tc` \ inst_env -> + case lookupInstEnv inst_env clas tys of + FoundInst tenv dfun + -> returnNF_Tc (Just (substClasses (mkSubst emptyInScopeSet tenv) theta')) where (_, theta, _) = splitSigmaTy (idType dfun) -\end{code} - - + theta' = map (\(Class clas tys) -> (clas,tys)) theta -%************************************************************************ -%* * -\subsection[Inst-origin]{The @InstOrigin@ type} -%* * -%************************************************************************ - -The @InstOrigin@ type gives information about where a dictionary came from. -This is important for decent error message reporting because dictionaries -don't appear in the original source code. Doubtless this type will evolve... - -\begin{code} -data InstOrigin s - = OccurrenceOf (TcIdOcc s) -- Occurrence of an overloaded identifier - | OccurrenceOfCon Id -- Occurrence of a data constructor - - | RecordUpdOrigin - - | DataDeclOrigin -- Typechecking a data declaration - - | InstanceDeclOrigin -- Typechecking an instance decl - - | LiteralOrigin HsLit -- Occurrence of a literal - - | ArithSeqOrigin RenamedArithSeqInfo -- [x..], [x..y] etc - - | SignatureOrigin -- A dict created from a type signature - | Rank2Origin -- A dict created when typechecking the argument - -- of a rank-2 typed function - - | DoOrigin -- The monad for a do expression - - | ClassDeclOrigin -- Manufactured during a class decl - - | InstanceSpecOrigin Class -- in a SPECIALIZE instance pragma - Type - - -- When specialising instances the instance info attached to - -- each class is not yet ready, so we record it inside the - -- origin information. This is a bit of a hack, but it works - -- fine. (Patrick is to blame [WDP].) - - | ValSpecOrigin Name -- in a SPECIALIZE pragma for a value - - -- Argument or result of a ccall - -- Dictionaries with this origin aren't actually mentioned in the - -- translated term, and so need not be bound. Nor should they - -- be abstracted over. - - | CCallOrigin String -- CCall label - (Maybe RenamedHsExpr) -- Nothing if it's the result - -- Just arg, for an argument - - | LitLitOrigin String -- the litlit - - | UnknownOrigin -- Help! I give up... + other -> returnNF_Tc Nothing \end{code} -\begin{code} -pprOrigin :: Inst s -> SDoc -pprOrigin inst - = hsep [text "arising from", pp_orig orig, text "at", ppr locn] - where - (orig, locn) = case inst of - Dict _ _ _ orig loc -> (orig,loc) - Method _ _ _ _ _ orig loc -> (orig,loc) - LitInst _ _ _ orig loc -> (orig,loc) - - pp_orig (OccurrenceOf id) - = hsep [ptext SLIT("use of"), quotes (ppr id)] - pp_orig (OccurrenceOfCon id) - = hsep [ptext SLIT("use of"), quotes (ppr id)] - pp_orig (LiteralOrigin lit) - = hsep [ptext SLIT("the literal"), quotes (ppr lit)] - pp_orig (InstanceDeclOrigin) - = ptext SLIT("an instance declaration") - pp_orig (ArithSeqOrigin seq) - = hsep [ptext SLIT("the arithmetic sequence"), quotes (ppr seq)] - pp_orig (SignatureOrigin) - = ptext SLIT("a type signature") - pp_orig (Rank2Origin) - = ptext SLIT("a function with an overloaded argument type") - pp_orig (DoOrigin) - = ptext SLIT("a do statement") - pp_orig (ClassDeclOrigin) - = ptext SLIT("a class declaration") - pp_orig (InstanceSpecOrigin clas ty) - = hsep [text "a SPECIALIZE instance pragma; class", - quotes (ppr clas), text "type:", ppr ty] - pp_orig (ValSpecOrigin name) - = hsep [ptext SLIT("a SPECIALIZE user-pragma for"), quotes (ppr name)] - pp_orig (CCallOrigin clabel Nothing{-ccall result-}) - = hsep [ptext SLIT("the result of the _ccall_ to"), quotes (text clabel)] - pp_orig (CCallOrigin clabel (Just arg_expr)) - = hsep [ptext SLIT("an argument in the _ccall_ to"), quotes (text clabel) <> comma, - text "namely", quotes (ppr arg_expr)] - pp_orig (LitLitOrigin s) - = hsep [ptext SLIT("the ``literal-literal''"), quotes (text s)] - pp_orig (UnknownOrigin) - = ptext SLIT("...oops -- I don't know where the overloading came from!") -\end{code} +