X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=ghc%2Fcompiler%2Ftypecheck%2FTcEnv.lhs;h=1c7e72228248006d44b66c01c29893e05724906c;hb=d068f518de21a7a21613eb5a34c5eac8517bef75;hp=6ac4272f4adda6295a15bb98545fb36b350c61cb;hpb=204105777c7a67e99ccdc88106255bb83a033f1c;p=ghc-hetmet.git diff --git a/ghc/compiler/typecheck/TcEnv.lhs b/ghc/compiler/typecheck/TcEnv.lhs index 6ac4272..1c7e722 100644 --- a/ghc/compiler/typecheck/TcEnv.lhs +++ b/ghc/compiler/typecheck/TcEnv.lhs @@ -3,8 +3,8 @@ module TcEnv( TyThing(..), TcTyThing(..), TcId, -- Instance environment, and InstInfo type - InstInfo(..), pprInstInfo, pprInstInfoDetails, - simpleInstInfoTy, simpleInstInfoTyCon, + InstInfo(..), iDFunId, pprInstInfo, pprInstInfoDetails, + simpleInstInfoClsTy, simpleInstInfoTy, simpleInstInfoTyCon, InstBindings(..), -- Global environment @@ -13,18 +13,16 @@ module TcEnv( tcLookupLocatedGlobal, tcLookupGlobal, tcLookupGlobalId, tcLookupTyCon, tcLookupClass, tcLookupDataCon, tcLookupLocatedGlobalId, tcLookupLocatedTyCon, - tcLookupLocatedClass, tcLookupLocatedDataCon, + tcLookupLocatedClass, - getInGlobalScope, - -- Local environment - tcExtendKindEnv, - tcExtendTyVarEnv, tcExtendTyVarEnv2, - tcExtendLocalValEnv, tcExtendLocalValEnv2, + tcExtendKindEnv, tcExtendKindEnvTvs, + tcExtendTyVarEnv, tcExtendTyVarEnv2, + tcExtendIdEnv, tcExtendIdEnv1, tcExtendIdEnv2, tcLookup, tcLookupLocated, tcLookupLocalIds, tcLookupId, tcLookupTyVar, lclEnvElts, getInLocalScope, findGlobals, - wrongThingErr, + wrongThingErr, pprBinders, tcExtendRecEnv, -- For knot-tying @@ -38,43 +36,43 @@ module TcEnv( checkWellStaged, spliceOK, bracketOK, tcMetaTy, thLevel, topIdLvl, - -- Arrow stuff - checkProcLevel, - -- New Ids newLocalName, newDFunName ) where #include "HsVersions.h" -import HsSyn ( LRuleDecl, LHsBinds, LSig, pprLHsBinds ) +import HsSyn ( LRuleDecl, LHsBinds, LSig, + LHsTyVarBndr, HsTyVarBndr(..), pprLHsBinds ) import TcIface ( tcImportDecl ) +import IfaceEnv ( newGlobalBinder ) import TcRnMonad -import TcMType ( zonkTcType, zonkTcTyVar, zonkTcTyVarsAndFV ) -import TcType ( Type, TcKind, TcTyVar, TcTyVarSet, - tyVarsOfType, tyVarsOfTypes, tcSplitDFunTy, mkGenTyConApp, - getDFunTyKey, tcTyConAppTyCon, tyVarBindingInfo, - tidyOpenType, tidyOpenTyVar +import TcMType ( zonkTcType, zonkTcTyVarsAndFV ) +import TcType ( Type, TcKind, TcTyVar, TcTyVarSet, TcType, + tyVarsOfType, tyVarsOfTypes, mkGenTyConApp, + getDFunTyKey, tcTyConAppTyCon, tcGetTyVar, mkTyVarTy, + tidyOpenType ) import qualified Type ( getTyVar_maybe ) import Id ( idName, isLocalId ) -import Var ( TyVar, Id, idType ) +import Var ( TyVar, Id, idType, tyVarName ) import VarSet import VarEnv import RdrName ( extendLocalRdrEnv ) +import InstEnv ( Instance, DFunId, instanceDFunId, instanceHead ) import DataCon ( DataCon ) import TyCon ( TyCon ) import Class ( Class ) -import Name ( Name, NamedThing(..), getSrcLoc, mkInternalName, nameIsLocalOrFrom ) +import Name ( Name, NamedThing(..), getSrcLoc, nameModule ) +import PrelNames ( thFAKE ) import NameEnv import OccName ( mkDFunOcc, occNameString ) -import HscTypes ( DFunId, extendTypeEnvList, lookupType, +import HscTypes ( extendTypeEnvList, lookupType, TyThing(..), tyThingId, tyThingDataCon, ExternalPackageState(..) ) import SrcLoc ( SrcLoc, Located(..) ) import Outputable -import Maybe ( isJust ) \end{code} @@ -96,24 +94,30 @@ tcLookupLocatedGlobal name tcLookupGlobal :: Name -> TcM TyThing tcLookupGlobal name - = do { env <- getGblEnv - ; if nameIsLocalOrFrom (tcg_mod env) name - - then -- It's defined in this module - case lookupNameEnv (tcg_type_env env) name of - Just thing -> return thing - Nothing -> notFound "tcLookupGlobal" name + = ASSERT( isGlobalName name ) + do { env <- getGblEnv + + -- Try local envt + ; case lookupNameEnv (tcg_type_env env) name of { + Just thing -> return thing ; + Nothing -> do - else do -- It's imported + -- Try global envt { (eps,hpt) <- getEpsAndHpt - ; case lookupType hpt (eps_PTE eps) name of - Just thing -> return thing - Nothing -> do { traceIf (text "tcLookupGlobal" <+> ppr name) - ; initIfaceTcRn (tcImportDecl name) } - }} -\end{code} + ; case lookupType hpt (eps_PTE eps) name of { + Just thing -> return thing ; + Nothing -> do + + -- Should it have been in the local envt? + { let mod = nameModule name + ; if mod == tcg_mod env || mod == thFAKE then + notFound name -- It should be local, so panic + -- The thFAKE possibility is because it + -- might be in a declaration bracket + else + tcImportDecl name -- Go find it in an interface + }}}}} -\begin{code} tcLookupGlobalId :: Name -> TcM Id -- Never used for Haskell-source DataCons, hence no ADataCon case tcLookupGlobalId name @@ -142,9 +146,6 @@ tcLookupTyCon name tcLookupLocatedGlobalId :: Located Name -> TcM Id tcLookupLocatedGlobalId = addLocM tcLookupId -tcLookupLocatedDataCon :: Located Name -> TcM DataCon -tcLookupLocatedDataCon = addLocM tcLookupDataCon - tcLookupLocatedClass :: Located Name -> TcM Class tcLookupLocatedClass = addLocM tcLookupClass @@ -174,21 +175,6 @@ tcExtendGlobalValEnv ids thing_inside = tcExtendGlobalEnv [AnId id | id <- ids] thing_inside \end{code} -A variety of global lookups, when we know what we are looking for. - -\begin{code} -getInGlobalScope :: TcM (Name -> Bool) --- Get all things in the global environment; used for deciding what --- rules to suck in. Anything defined in this module (nameIsLocalOrFrom) --- is certainly in the envt, so we don't bother to look. -getInGlobalScope - = do { mod <- getModule - ; (eps,hpt) <- getEpsAndHpt - ; return (\n -> nameIsLocalOrFrom mod n || - isJust (lookupType hpt (eps_PTE eps) n)) } -\end{code} - - \begin{code} tcExtendRecEnv :: [(Name,TyThing)] -> TcM r -> TcM r -- Extend the global environments for the type/class knot tying game @@ -218,12 +204,12 @@ tcLookup name Nothing -> tcLookupGlobal name `thenM` \ thing -> returnM (AGlobal thing) -tcLookupTyVar :: Name -> TcM Id +tcLookupTyVar :: Name -> TcM TcTyVar tcLookupTyVar name = tcLookup name `thenM` \ thing -> case thing of - ATyVar tv -> returnM tv - other -> pprPanic "tcLookupTyVar" (ppr name) + ATyVar _ ty -> returnM (tcGetTyVar "tcLookupTyVar" ty) + other -> pprPanic "tcLookupTyVar" (ppr name) tcLookupId :: Name -> TcM Id -- Used when we aren't interested in the binding level @@ -231,7 +217,7 @@ tcLookupId :: Name -> TcM Id tcLookupId name = tcLookup name `thenM` \ thing -> case thing of - ATcId tc_id _ _ -> returnM tc_id + ATcId tc_id _ -> returnM tc_id AGlobal (AnId id) -> returnM id other -> pprPanic "tcLookupId" (ppr name) @@ -244,8 +230,8 @@ tcLookupLocalIds ns where lookup lenv lvl name = case lookupNameEnv lenv name of - Just (ATcId id lvl1 _) -> ASSERT( lvl == lvl1 ) id - other -> pprPanic "tcLookupLocalIds" (ppr name) + Just (ATcId id lvl1) -> ASSERT( lvl == lvl1 ) id + other -> pprPanic "tcLookupLocalIds" (ppr name) lclEnvElts :: TcLclEnv -> [TcTyThing] lclEnvElts env = nameEnvElts (tcl_env env) @@ -267,24 +253,27 @@ tcExtendKindEnv things thing_inside upd lcl_env = lcl_env { tcl_env = extend (tcl_env lcl_env) } extend env = extendNameEnvList env [(n, AThing k) | (n,k) <- things] +tcExtendKindEnvTvs :: [LHsTyVarBndr Name] -> TcM r -> TcM r +tcExtendKindEnvTvs bndrs thing_inside + = updLclEnv upd thing_inside + where + upd lcl_env = lcl_env { tcl_env = extend (tcl_env lcl_env) } + extend env = extendNameEnvList env pairs + pairs = [(n, AThing k) | L _ (KindedTyVar n k) <- bndrs] + tcExtendTyVarEnv :: [TyVar] -> TcM r -> TcM r tcExtendTyVarEnv tvs thing_inside - = tc_extend_tv_env [(getName tv, ATyVar tv) | tv <- tvs] tvs thing_inside - -tcExtendTyVarEnv2 :: [(TyVar,TcTyVar)] -> TcM r -> TcM r -tcExtendTyVarEnv2 tv_pairs thing_inside - = tc_extend_tv_env [(getName tv1, ATyVar tv2) | (tv1,tv2) <- tv_pairs] - [tv | (_,tv) <- tv_pairs] - thing_inside + = tcExtendTyVarEnv2 [(tyVarName tv, mkTyVarTy tv) | tv <- tvs] thing_inside -tc_extend_tv_env binds tyvars thing_inside +tcExtendTyVarEnv2 :: [(Name,TcType)] -> TcM r -> TcM r +tcExtendTyVarEnv2 binds thing_inside = getLclEnv `thenM` \ env@(TcLclEnv {tcl_env = le, tcl_tyvars = gtvs, tcl_rdr = rdr_env}) -> let - le' = extendNameEnvList le binds rdr_env' = extendLocalRdrEnv rdr_env (map fst binds) - new_tv_set = mkVarSet tyvars + new_tv_set = tyVarsOfTypes (map snd binds) + le' = extendNameEnvList le [(name, ATyVar name ty) | (name, ty) <- binds] in -- It's important to add the in-scope tyvars to the global tyvar set -- as well. Consider @@ -298,28 +287,26 @@ tc_extend_tv_env binds tyvars thing_inside \begin{code} -tcExtendLocalValEnv :: [TcId] -> TcM a -> TcM a -tcExtendLocalValEnv ids thing_inside - = getLclEnv `thenM` \ env -> - let - extra_global_tyvars = tyVarsOfTypes [idType id | id <- ids] - th_lvl = thLevel (tcl_th_ctxt env) - proc_lvl = proc_level (tcl_arrow_ctxt env) - extra_env = [(idName id, ATcId id th_lvl proc_lvl) | id <- ids] - le' = extendNameEnvList (tcl_env env) extra_env - rdr_env' = extendLocalRdrEnv (tcl_rdr env) (map idName ids) - in - tc_extend_gtvs (tcl_tyvars env) extra_global_tyvars `thenM` \ gtvs' -> - setLclEnv (env {tcl_env = le', tcl_tyvars = gtvs', tcl_rdr = rdr_env'}) thing_inside - -tcExtendLocalValEnv2 :: [(Name,TcId)] -> TcM a -> TcM a -tcExtendLocalValEnv2 names_w_ids thing_inside +tcExtendIdEnv :: [TcId] -> TcM a -> TcM a +-- Invariant: the TcIds are fully zonked. Reasons: +-- (a) The kinds of the forall'd type variables are defaulted +-- (see Kind.defaultKind, done in zonkQuantifiedTyVar) +-- (b) There are no via-Indirect occurrences of the bound variables +-- in the types, because instantiation does not look through such things +-- (c) The call to tyVarsOfTypes is ok without looking through refs +tcExtendIdEnv ids thing_inside = tcExtendIdEnv2 [(idName id, id) | id <- ids] thing_inside + +tcExtendIdEnv1 :: Name -> TcId -> TcM a -> TcM a +tcExtendIdEnv1 name id thing_inside = tcExtendIdEnv2 [(name,id)] thing_inside + +tcExtendIdEnv2 :: [(Name,TcId)] -> TcM a -> TcM a +-- Invariant: the TcIds are fully zonked (see tcExtendIdEnv above) +tcExtendIdEnv2 names_w_ids thing_inside = getLclEnv `thenM` \ env -> let extra_global_tyvars = tyVarsOfTypes [idType id | (name,id) <- names_w_ids] th_lvl = thLevel (tcl_th_ctxt env) - proc_lvl = proc_level (tcl_arrow_ctxt env) - extra_env = [(name, ATcId id th_lvl proc_lvl) | (name,id) <- names_w_ids] + extra_env = [(name, ATcId id th_lvl) | (name,id) <- names_w_ids] le' = extendNameEnvList (tcl_env env) extra_env rdr_env' = extendLocalRdrEnv (tcl_rdr env) (map fst names_w_ids) in @@ -353,7 +340,7 @@ findGlobals tvs tidy_env ignore_it ty = not (tvs `intersectsVarSet` tyVarsOfType ty) ----------------------- -find_thing ignore_it tidy_env (ATcId id _ _) +find_thing ignore_it tidy_env (ATcId id _) = zonkTcType (idType id) `thenM` \ id_ty -> if ignore_it id_ty then returnM (tidy_env, Nothing) @@ -365,23 +352,22 @@ find_thing ignore_it tidy_env (ATcId id _ _) in returnM (tidy_env', Just msg) -find_thing ignore_it tidy_env (ATyVar tv) - = zonkTcTyVar tv `thenM` \ tv_ty -> +find_thing ignore_it tidy_env (ATyVar tv ty) + = zonkTcType ty `thenM` \ tv_ty -> if ignore_it tv_ty then returnM (tidy_env, Nothing) else let - (tidy_env1, tv1) = tidyOpenTyVar tidy_env tv - (tidy_env2, tidy_ty) = tidyOpenType tidy_env1 tv_ty - msg = sep [ppr tv1 <+> eq_stuff, nest 2 bound_at] + -- The name tv is scoped, so we don't need to tidy it + (tidy_env1, tidy_ty) = tidyOpenType tidy_env tv_ty + msg = sep [ptext SLIT("Scoped type variable") <+> quotes (ppr tv) <+> eq_stuff, nest 2 bound_at] eq_stuff | Just tv' <- Type.getTyVar_maybe tv_ty, - tv == tv' = empty + getOccName tv == getOccName tv' = empty | otherwise = equals <+> ppr tidy_ty -- It's ok to use Type.getTyVar_maybe because ty is zonked by now - - bound_at = tyVarBindingInfo tv + bound_at = parens $ ptext SLIT("bound at:") <+> ppr (getSrcLoc tv) in - returnM (tidy_env2, Just msg) + returnM (tidy_env1, Just msg) \end{code} @@ -434,25 +420,6 @@ tcExtendRules lcl_rules thing_inside %************************************************************************ %* * - Arrow notation proc levels -%* * -%************************************************************************ - -\begin{code} -checkProcLevel :: TcId -> ProcLevel -> TcM () -checkProcLevel id id_lvl - = do { banned <- getBannedProcLevels - ; checkTc (not (id_lvl `elem` banned)) - (procLevelErr id id_lvl) } - -procLevelErr id id_lvl - = hang (ptext SLIT("Command-bound variable") <+> quotes (ppr id) <+> ptext SLIT("is not in scope here")) - 4 (ptext SLIT("Reason: it is used in the left argument of (-<)")) -\end{code} - - -%************************************************************************ -%* * Meta level %* * %************************************************************************ @@ -495,7 +462,7 @@ checkWellStaged pp_thing bind_lvl use_stage topIdLvl :: Id -> ThLevel -- Globals may either be imported, or may be from an earlier "chunk" -- (separated by declaration splices) of this module. The former --- *can* be used inside a top-level splice, but the latter cannot. +-- *can* be used inside a top-level splice, but the latter cannot. -- Hence we give the former impLevel, but the latter topLevel -- E.g. this is bad: -- x = [| foo |] @@ -508,7 +475,7 @@ topIdLvl id | isLocalId id = topLevel -- Indicates the legal transitions on bracket( [| |] ). bracketOK :: ThStage -> Maybe ThLevel bracketOK (Brack _ _ _) = Nothing -- Bracket illegal inside a bracket -bracketOK stage = (Just (thLevel stage + 1)) +bracketOK stage = Just (thLevel stage + 1) -- Indicates the legal transitions on splice($). spliceOK :: ThStage -> Maybe ThLevel @@ -528,40 +495,6 @@ tcMetaTy tc_name %************************************************************************ %* * -\subsection{Making new Ids} -%* * -%************************************************************************ - -Constructing new Ids - -\begin{code} -newLocalName :: Name -> TcM Name -newLocalName name -- Make a clone - = newUnique `thenM` \ uniq -> - returnM (mkInternalName uniq (getOccName name) (getSrcLoc name)) -\end{code} - -Make a name for the dict fun for an instance decl. It's a *local* -name for the moment. The CoreTidy pass will externalise it. Even in ---make and ghci stuff, we rebuild the instance environment each time, -so the dfun id is internal to begin with, and external when compiling -other modules - -\begin{code} -newDFunName :: Class -> [Type] -> SrcLoc -> TcM Name -newDFunName clas (ty:_) loc - = newUnique `thenM` \ uniq -> - returnM (mkInternalName uniq (mkDFunOcc dfun_string) loc) - where - -- Any string that is somewhat unique will do - dfun_string = occNameString (getOccName clas) ++ occNameString (getDFunTyKey ty) - -newDFunName clas [] loc = pprPanic "newDFunName" (ppr clas <+> ppr loc) -\end{code} - - -%************************************************************************ -%* * \subsection{The InstInfo type} %* * %************************************************************************ @@ -579,10 +512,13 @@ as well as explicit user written ones. \begin{code} data InstInfo = InstInfo { - iDFunId :: DFunId, -- The dfun id - iBinds :: InstBindings + iSpec :: Instance, -- Includes the dfun id. Its forall'd type + iBinds :: InstBindings -- variables scope over the stuff in InstBindings! } +iDFunId :: InstInfo -> DFunId +iDFunId info = instanceDFunId (iSpec info) + data InstBindings = VanillaInst -- The normal case (LHsBinds Name) -- Bindings @@ -602,9 +538,12 @@ pprInstInfoDetails info = pprInstInfo info $$ nest 2 (details (iBinds info)) details (VanillaInst b _) = pprLHsBinds b details (NewTypeDerived _) = text "Derived from the representation type" +simpleInstInfoClsTy :: InstInfo -> (Class, Type) +simpleInstInfoClsTy info = case instanceHead (iSpec info) of + (_, _, cls, [ty]) -> (cls, ty) + simpleInstInfoTy :: InstInfo -> Type -simpleInstInfoTy info = case tcSplitDFunTy (idType (iDFunId info)) of - (_, _, _, [ty]) -> ty +simpleInstInfoTy info = snd (simpleInstInfoClsTy info) simpleInstInfoTyCon :: InstInfo -> TyCon -- Gets the type constructor for a simple instance declaration, @@ -612,6 +551,24 @@ simpleInstInfoTyCon :: InstInfo -> TyCon simpleInstInfoTyCon inst = tcTyConAppTyCon (simpleInstInfoTy inst) \end{code} +Make a name for the dict fun for an instance decl. It's an *external* +name, like otber top-level names, and hence must be made with newGlobalBinder. + +\begin{code} +newDFunName :: Class -> [Type] -> SrcLoc -> TcM Name +newDFunName clas (ty:_) loc + = do { index <- nextDFunIndex + ; is_boot <- tcIsHsBoot + ; mod <- getModule + ; let info_string = occNameString (getOccName clas) ++ + occNameString (getDFunTyKey ty) + dfun_occ = mkDFunOcc info_string is_boot index + + ; newGlobalBinder mod dfun_occ Nothing loc } + +newDFunName clas [] loc = pprPanic "newDFunName" (ppr clas <+> ppr loc) +\end{code} + %************************************************************************ %* * @@ -620,17 +577,17 @@ simpleInstInfoTyCon inst = tcTyConAppTyCon (simpleInstInfoTy inst) %************************************************************************ \begin{code} -notFound wheRe name = failWithTc (text wheRe <> colon <+> quotes (ppr name) <+> - ptext SLIT("is not in scope")) +pprBinders :: [Name] -> SDoc +-- Used in error messages +-- Use quotes for a single one; they look a bit "busy" for several +pprBinders [bndr] = quotes (ppr bndr) +pprBinders bndrs = pprWithCommas ppr bndrs + +notFound name + = failWithTc (ptext SLIT("GHC internal error:") <+> quotes (ppr name) <+> + ptext SLIT("is not in scope")) wrongThingErr expected thing name - = failWithTc (pp_thing thing <+> quotes (ppr name) <+> + = failWithTc (pprTcTyThingCategory thing <+> quotes (ppr name) <+> ptext SLIT("used as a") <+> text expected) - where - pp_thing (AGlobal (ATyCon _)) = ptext SLIT("Type constructor") - pp_thing (AGlobal (AClass _)) = ptext SLIT("Class") - pp_thing (AGlobal (AnId _)) = ptext SLIT("Identifier") - pp_thing (AGlobal (ADataCon _)) = ptext SLIT("Data constructor") - pp_thing (ATyVar _) = ptext SLIT("Type variable") - pp_thing (ATcId _ _ _) = ptext SLIT("Local identifier") \end{code}