\begin{code}
module TcEnv(
- TcIdOcc(..), TcIdBndr, tcIdType, tcIdTyVars, tcInstId,
-
- TcEnv,
-
- initEnv, getEnv_LocalIds, getEnv_TyCons, getEnv_Classes,
-
- tcExtendTyVarEnv, tcLookupTyVar,
-
- tcExtendTyConEnv, tcLookupTyCon, tcLookupTyConByKey,
- tcExtendClassEnv, tcLookupClass, tcLookupClassByKey,
- tcGetTyConsAndClasses,
-
- tcExtendGlobalValEnv, tcExtendLocalValEnv,
- tcLookupLocalValue, tcLookupLocalValueOK, tcLookupLocalValueByKey,
- tcLookupGlobalValue, tcLookupGlobalValueByKey, tcLookupGlobalValueMaybe,
- tcAddImportedIdInfo, tcExplicitLookupGlobal,
- tcLookupGlobalValueByKeyMaybe,
-
- newMonoIds, newLocalIds, newLocalId,
- tcGetGlobalTyVars, tcExtendGlobalTyVars
+ TyThing(..), TyThingDetails(..), TcTyThing(..), TcId,
+
+ -- Instance environment, and InstInfo type
+ tcGetInstEnv,
+ InstInfo(..), pprInstInfo, pprInstInfoDetails,
+ simpleInstInfoTy, simpleInstInfoTyCon,
+ InstBindings(..),
+
+ -- Global environment
+ tcExtendGlobalEnv,
+ tcExtendGlobalValEnv,
+ tcExtendGlobalTypeEnv,
+ tcLookupTyCon, tcLookupClass, tcLookupDataCon,
+ tcLookupGlobal_maybe, tcLookupGlobal, tcLookupGlobalId,
+ getInGlobalScope,
+
+ -- Local environment
+ tcExtendKindEnv,
+ tcExtendTyVarEnv, tcExtendTyVarEnv2,
+ tcExtendLocalValEnv, tcExtendLocalValEnv2,
+ tcLookup, tcLookupLocalIds, tcLookup_maybe,
+ tcLookupId,
+ lclEnvElts, getInLocalScope, findGlobals,
+
+ -- Instance environment
+ tcExtendLocalInstEnv, tcExtendInstEnv, tcExtendTempInstEnv, tcWithTempInstEnv,
+
+ -- Rules
+ tcExtendRules,
+
+ -- Global type variables
+ tcGetGlobalTyVars,
+
+ -- Template Haskell stuff
+ checkWellStaged, spliceOK, bracketOK, tcMetaTy, thLevel,
+ topIdLvl,
+
+ -- Arrow stuff
+ checkProcLevel,
+
+ -- New Ids
+ newLocalName, newDFunName,
+
+ -- Misc
+ isLocalThing
) where
#include "HsVersions.h"
-import Id ( Id, GenId, idType, mkUserLocal, mkUserId, replaceIdInfo, getIdInfo )
-import PragmaInfo ( PragmaInfo(..) )
-import TcKind ( TcKind, kindToTcKind, Kind )
-import TcType ( TcType, TcMaybe, TcTyVar, TcTyVarSet, TcThetaType,
- newTyVarTys, tcInstTyVars, zonkTcTyVars, tcInstType
- )
-import TyVar ( mkTyVarSet, unionTyVarSets, emptyTyVarSet, TyVar )
-import PprType ( GenTyVar )
-import Type ( tyVarsOfType, tyVarsOfTypes, splitForAllTys, splitRhoTy )
-import TyCon ( TyCon, tyConKind, tyConArity, isSynTyCon, Arity )
-import Class ( Class )
-
-import TcMonad
-
-import IdInfo ( noIdInfo )
-import Name ( Name, OccName(..),
- maybeWiredInTyConName, maybeWiredInIdName, isLocallyDefined,
- NamedThing(..)
+import RnHsSyn ( RenamedMonoBinds, RenamedSig )
+import HsSyn ( RuleDecl(..), ifaceRuleDeclName )
+import TcRnMonad
+import TcMType ( zonkTcType, zonkTcTyVar, zonkTcTyVarsAndFV )
+import TcType ( Type, ThetaType, TcKind, TcTyVar, TcTyVarSet,
+ tyVarsOfType, tyVarsOfTypes, tcSplitDFunTy, mkGenTyConApp,
+ getDFunTyKey, tcTyConAppTyCon, tyVarBindingInfo,
+ tidyOpenType, tidyOpenTyVar
)
-import Unique ( pprUnique10{-, pprUnique ToDo:rm-}, Unique, Uniquable(..) )
-import UniqFM
-import Util ( zipEqual, zipWithEqual, zipWith3Equal )
-import Maybes ( maybeToBool )
+import qualified Type ( getTyVar_maybe )
+import Rules ( extendRuleBase )
+import Id ( idName, isLocalId )
+import Var ( TyVar, Id, idType )
+import VarSet
+import VarEnv
+import CoreSyn ( IdCoreRule )
+import DataCon ( DataCon )
+import TyCon ( TyCon, DataConDetails )
+import Class ( Class, ClassOpItem )
+import Name ( Name, NamedThing(..),
+ getSrcLoc, mkInternalName, nameIsLocalOrFrom
+ )
+import NameEnv
+import OccName ( mkDFunOcc, occNameString )
+import HscTypes ( DFunId, TypeEnv, extendTypeEnvList, lookupType,
+ TyThing(..), ExternalPackageState(..) )
+import Rules ( RuleBase )
+import BasicTypes ( EP )
+import Module ( Module )
+import InstEnv ( InstEnv, extendInstEnv )
+import SrcLoc ( SrcLoc )
import Outputable
+import Maybe ( isJust )
+import List ( partition )
\end{code}
+
%************************************************************************
%* *
-\subsection{TcId, TcIdOcc}
+ 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
+%* *
+%************************************************************************
\begin{code}
-type TcIdBndr s = GenId (TcType s) -- Binders are all TcTypes
-data TcIdOcc s = TcId (TcIdBndr s) -- Bindees may be either
- | RealId Id
+instance Outputable ThStage where
+ ppr Comp = text "Comp"
+ ppr (Brack l _ _) = text "Brack" <+> int l
+ ppr (Splice l) = text "Splice" <+> int l
+
+
+thLevel :: ThStage -> ThLevel
+thLevel Comp = topLevel
+thLevel (Splice l) = l
+thLevel (Brack l _ _) = l
+
+
+checkWellStaged :: SDoc -- What the stage check is for
+ -> ThLevel -- Binding level
+ -> ThStage -- Use stage
+ -> TcM () -- Fail if badly staged, adding an error
+checkWellStaged pp_thing bind_lvl use_stage
+ | bind_lvl <= use_lvl -- OK!
+ = returnM ()
+
+ | bind_lvl == topLevel -- GHC restriction on top level splices
+ = failWithTc $
+ sep [ptext SLIT("GHC stage restriction:") <+> pp_thing,
+ nest 2 (ptext SLIT("is used in a top-level splice, and must be imported, not defined locally"))]
+
+ | otherwise -- Badly staged
+ = failWithTc $
+ ptext SLIT("Stage error:") <+> pp_thing <+>
+ hsep [ptext SLIT("is bound at stage") <+> ppr bind_lvl,
+ ptext SLIT("but used at stage") <+> ppr use_lvl]
+ where
+ use_lvl = thLevel 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.
+-- Hence we give the former impLevel, but the latter topLevel
+-- E.g. this is bad:
+-- x = [| foo |]
+-- $( f x )
+-- By the time we are prcessing the $(f x), the binding for "x"
+-- will be in the global env, not the local one.
+topIdLvl id | isLocalId id = topLevel
+ | otherwise = impLevel
+
+-- Indicates the legal transitions on bracket( [| |] ).
+bracketOK :: ThStage -> Maybe ThLevel
+bracketOK (Brack _ _ _) = Nothing -- Bracket illegal inside a bracket
+bracketOK stage = (Just (thLevel stage + 1))
+
+-- Indicates the legal transitions on splice($).
+spliceOK :: ThStage -> Maybe ThLevel
+spliceOK (Splice _) = Nothing -- Splice illegal inside splice
+spliceOK stage = Just (thLevel stage - 1)
+
+tcMetaTy :: Name -> TcM Type
+-- Given the name of a Template Haskell data type,
+-- return the type
+-- E.g. given the name "Expr" return the type "Expr"
+tcMetaTy tc_name
+ = tcLookupTyCon tc_name `thenM` \ t ->
+ returnM (mkGenTyConApp t [])
+ -- Use mkGenTyConApp because it might be a synonym
+\end{code}
-instance Eq (TcIdOcc s) where
- (TcId id1) == (TcId id2) = id1 == id2
- (RealId id1) == (RealId id2) = id1 == id2
- _ == _ = False
-instance Ord (TcIdOcc s) where
- (TcId id1) `compare` (TcId id2) = id1 `compare` id2
- (RealId id1) `compare` (RealId id2) = id1 `compare` id2
- (TcId _) `compare` (RealId _) = LT
- (RealId _) `compare` (TcId _) = GT
+%************************************************************************
+%* *
+\subsection{TyThingDetails}
+%* *
+%************************************************************************
-instance Outputable (TcIdOcc s) where
- ppr (TcId id) = ppr id
- ppr (RealId id) = ppr id
+This data type is used to help tie the knot
+ when type checking type and class declarations
-instance NamedThing (TcIdOcc s) where
- getName (TcId id) = getName id
- getName (RealId id) = getName id
+\begin{code}
+data TyThingDetails = SynTyDetails Type
+ | DataTyDetails ThetaType (DataConDetails DataCon) [Id] (Maybe (EP Id))
+ | ClassDetails ThetaType [Id] [ClassOpItem] DataCon Name
+ -- The Name is the Name of the implicit TyCon for the class
+ | ForeignTyDetails -- Nothing yet
+\end{code}
-tcIdType :: TcIdOcc s -> TcType s
-tcIdType (TcId id) = idType id
-tcIdType (RealId id) = pprPanic "tcIdType:" (ppr id)
+%************************************************************************
+%* *
+\subsection{Making new Ids}
+%* *
+%************************************************************************
-tcIdTyVars (TcId id) = tyVarsOfType (idType id)
-tcIdTyVars (RealId _) = emptyTyVarSet -- Top level Ids have no free type variables
+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
--- A useful function that takes an occurrence of a global thing
--- and instantiates its type with fresh type variables
-tcInstId :: Id
- -> NF_TcM s ([TcTyVar s], -- It's instantiated type
- TcThetaType s, --
- TcType s) --
+\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)
-tcInstId id
- = let
- (tyvars, rho) = splitForAllTys (idType id)
- in
- tcInstTyVars tyvars `thenNF_Tc` \ (tyvars', arg_tys, tenv) ->
- tcInstType tenv rho `thenNF_Tc` \ rho' ->
- let
- (theta', tau') = splitRhoTy rho'
- in
- returnNF_Tc (tyvars', theta', tau')
+newDFunName clas [] loc = pprPanic "newDFunName" (ppr clas <+> ppr loc)
\end{code}
+\begin{code}
+isLocalThing :: NamedThing a => Module -> a -> Bool
+isLocalThing mod thing = nameIsLocalOrFrom mod (getName thing)
+\end{code}
%************************************************************************
%* *
-\subsection{TcEnv}
+\subsection{The global environment}
%* *
%************************************************************************
-Data type declarations
-~~~~~~~~~~~~~~~~~~~~~
+\begin{code}
+tcExtendGlobalEnv :: [TyThing] -> TcM r -> TcM r
+ -- Given a mixture of Ids, TyCons, Classes, perhaps from the
+ -- module being compiled, perhaps from a package module,
+ -- extend the global environment, and update the EPS
+tcExtendGlobalEnv things thing_inside
+ = do { eps <- getEps
+ ; hpt <- getHpt
+ ; env <- getGblEnv
+ ; let mod = tcg_mod env
+ (lcl_things, pkg_things) = partition (isLocalThing mod) things
+ ge' = extendTypeEnvList (tcg_type_env env) lcl_things
+ eps' = eps { eps_PTE = extendTypeEnvList (eps_PTE eps) pkg_things }
+ ; setEps eps'
+ ; setGblEnv (env {tcg_type_env = ge'}) thing_inside }
+
+tcExtendGlobalValEnv :: [Id] -> TcM a -> TcM a
+ -- Same deal as tcExtendGlobalEnv, but for Ids
+tcExtendGlobalValEnv ids thing_inside
+ = tcExtendGlobalEnv [AnId id | id <- ids] thing_inside
+
+tcExtendGlobalTypeEnv :: TypeEnv -> TcM r -> TcM r
+ -- Top-level things of the interactive context
+ -- No need to extend the package env
+tcExtendGlobalTypeEnv extra_env thing_inside
+ = do { env <- getGblEnv
+ ; let ge' = tcg_type_env env `plusNameEnv` extra_env
+ ; setGblEnv (env {tcg_type_env = ge'}) thing_inside }
+\end{code}
+
\begin{code}
-data TcEnv s = TcEnv
- (TyVarEnv s)
- (TyConEnv s)
- (ClassEnv s)
- (ValueEnv Id) -- Globals
- (ValueEnv (TcIdBndr s)) -- Locals
- (TcRef s (TcTyVarSet s)) -- Free type variables of locals
- -- ...why mutable? see notes with tcGetGlobalTyVars
-
-type TyVarEnv s = UniqFM (TcKind s, TyVar)
-type TyConEnv s = UniqFM (TcKind s, Maybe Arity, TyCon) -- Arity present for Synonyms only
-type ClassEnv s = UniqFM ([TcKind s], Class) -- The kinds are the kinds of the args
- -- to the class
-type ValueEnv id = UniqFM id
-
-initEnv :: TcRef s (TcTyVarSet s) -> TcEnv s
-initEnv mut = TcEnv emptyUFM emptyUFM emptyUFM emptyUFM emptyUFM mut
-
-getEnv_LocalIds (TcEnv _ _ _ _ ls _) = eltsUFM ls
-getEnv_TyCons (TcEnv _ ts _ _ _ _) = [tycon | (_, _, tycon) <- eltsUFM ts]
-getEnv_Classes (TcEnv _ _ cs _ _ _) = [clas | (_, clas) <- eltsUFM cs]
+tcLookupGlobal_maybe :: Name -> TcRn m (Maybe TyThing)
+-- This is a rather heavily-used function, so I've inlined a few things (e.g. getEps)
+-- Notice that for imported things we read the current version from the EPS
+-- mutable variable. This is important in situations like
+-- ...$(e1)...$(e2)...
+-- where the code that e1 expands to might import some defns that
+-- also turn out to be needed by the code that e2 expands to.
+tcLookupGlobal_maybe name
+ = do { env <- getGblEnv
+ ; if nameIsLocalOrFrom (tcg_mod env) name then
+ -- Defined in this module
+ return (lookupNameEnv (tcg_type_env env) name)
+ else
+ do { env <- getTopEnv
+ ; eps <- readMutVar (top_eps env)
+ ; return (lookupType (top_hpt env) (eps_PTE eps) name) }}
\end{code}
-Type variable env
-~~~~~~~~~~~~~~~~~
+A variety of global lookups, when we know what we are looking for.
+
\begin{code}
-tcExtendTyVarEnv :: [Name] -> [(TcKind s, TyVar)] -> TcM s r -> TcM s r
-tcExtendTyVarEnv names kinds_w_types scope
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- let
- tve' = addListToUFM tve (zipEqual "tcTyVarScope" names kinds_w_types)
- in
- tcSetEnv (TcEnv tve' tce ce gve lve gtvs) scope
+tcLookupGlobal :: Name -> TcM TyThing
+tcLookupGlobal name
+ = tcLookupGlobal_maybe name `thenM` \ maybe_thing ->
+ case maybe_thing of
+ Just thing -> returnM thing
+ other -> notFound "tcLookupGlobal" name
+
+tcLookupGlobalId :: Name -> TcM Id
+-- Never used for Haskell-source DataCons, hence no ADataCon case
+tcLookupGlobalId name
+ = tcLookupGlobal_maybe name `thenM` \ maybe_thing ->
+ case maybe_thing of
+ Just (AnId id) -> returnM id
+ other -> notFound "tcLookupGlobal (id)" name
+
+tcLookupDataCon :: Name -> TcM DataCon
+tcLookupDataCon con_name
+ = tcLookupGlobal_maybe con_name `thenM` \ maybe_thing ->
+ case maybe_thing of
+ Just (ADataCon data_con) -> returnM data_con
+ other -> notFound "tcLookupDataCon" con_name
+
+tcLookupClass :: Name -> TcM Class
+tcLookupClass name
+ = tcLookupGlobal_maybe name `thenM` \ maybe_clas ->
+ case maybe_clas of
+ Just (AClass clas) -> returnM clas
+ other -> notFound "tcLookupClass" name
+
+tcLookupTyCon :: Name -> TcM TyCon
+tcLookupTyCon name
+ = tcLookupGlobal_maybe name `thenM` \ maybe_tc ->
+ case maybe_tc of
+ Just (ATyCon tc) -> returnM tc
+ other -> notFound "tcLookupTyCon" name
+
+
+getInGlobalScope :: TcRn m (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 <- getEps
+ ; hpt <- getHpt
+ ; return (\n -> nameIsLocalOrFrom mod n ||
+ isJust (lookupType hpt (eps_PTE eps) n)) }
\end{code}
-The Kind, TyVar, Class and TyCon envs
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-Extending the environments.
+%************************************************************************
+%* *
+\subsection{The local environment}
+%* *
+%************************************************************************
\begin{code}
-tcExtendTyConEnv :: [(Name, (TcKind s, Maybe Arity, TyCon))] -> TcM s r -> TcM s r
-
-tcExtendTyConEnv bindings scope
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- let
- tce' = addListToUFM tce bindings
- in
- tcSetEnv (TcEnv tve tce' ce gve lve gtvs) scope
+tcLookup_maybe :: Name -> TcM (Maybe TcTyThing)
+tcLookup_maybe name
+ = getLclEnv `thenM` \ local_env ->
+ case lookupNameEnv (tcl_env local_env) name of
+ Just thing -> returnM (Just thing)
+ Nothing -> tcLookupGlobal_maybe name `thenM` \ mb_res ->
+ returnM (case mb_res of
+ Just thing -> Just (AGlobal thing)
+ Nothing -> Nothing)
+
+tcLookup :: Name -> TcM TcTyThing
+tcLookup name
+ = tcLookup_maybe name `thenM` \ maybe_thing ->
+ case maybe_thing of
+ Just thing -> returnM thing
+ other -> notFound "tcLookup" name
+ -- Extract the IdInfo from an IfaceSig imported from an interface file
+tcLookupId :: Name -> TcM Id
+-- Used when we aren't interested in the binding level
+-- Never a DataCon. (Why does that matter? see TcExpr.tcId)
+tcLookupId name
+ = tcLookup name `thenM` \ thing ->
+ case thing of
+ ATcId tc_id _ _ -> returnM tc_id
+ AGlobal (AnId id) -> returnM id
+ other -> pprPanic "tcLookupId" (ppr name)
+
+tcLookupLocalIds :: [Name] -> TcM [TcId]
+-- We expect the variables to all be bound, and all at
+-- the same level as the lookup. Only used in one place...
+tcLookupLocalIds ns
+ = getLclEnv `thenM` \ env ->
+ returnM (map (lookup (tcl_env env) (thLevel (tcl_th_ctxt env))) ns)
+ where
+ lookup lenv lvl name
+ = case lookupNameEnv lenv name of
+ Just (ATcId id lvl1 _) -> ASSERT( lvl == lvl1 ) id
+ other -> pprPanic "tcLookupLocalIds" (ppr name)
+
+lclEnvElts :: TcLclEnv -> [TcTyThing]
+lclEnvElts env = nameEnvElts (tcl_env env)
+
+getInLocalScope :: TcM (Name -> Bool)
+ -- Ids only
+getInLocalScope = getLclEnv `thenM` \ env ->
+ let
+ lcl_env = tcl_env env
+ in
+ return (`elemNameEnv` lcl_env)
+\end{code}
-tcExtendClassEnv :: [(Name, ([TcKind s], Class))] -> TcM s r -> TcM s r
-tcExtendClassEnv bindings scope
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
+\begin{code}
+tcExtendKindEnv :: [(Name,TcKind)] -> TcM r -> TcM r
+tcExtendKindEnv pairs thing_inside
+ = updLclEnv upd thing_inside
+ where
+ upd lcl_env = lcl_env { tcl_env = extend (tcl_env lcl_env) }
+ extend env = extendNameEnvList env [(n, AThing k) | (n,k) <- pairs]
+ -- No need to extend global tyvars for kind checking
+
+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
+
+tc_extend_tv_env binds tyvars thing_inside
+ = getLclEnv `thenM` \ env@(TcLclEnv {tcl_env = le, tcl_tyvars = gtvs}) ->
let
- ce' = addListToUFM ce bindings
+ le' = extendNameEnvList le binds
+ new_tv_set = mkVarSet tyvars
in
- tcSetEnv (TcEnv tve tce ce' gve lve gtvs) scope
+ -- It's important to add the in-scope tyvars to the global tyvar set
+ -- as well. Consider
+ -- f (x::r) = let g y = y::r in ...
+ -- Here, g mustn't be generalised. This is also important during
+ -- class and instance decls, when we mustn't generalise the class tyvars
+ -- when typechecking the methods.
+ tc_extend_gtvs gtvs new_tv_set `thenM` \ gtvs' ->
+ setLclEnv (env {tcl_env = le', tcl_tyvars = gtvs'}) thing_inside
\end{code}
-Looking up in the environments.
-
\begin{code}
-tcLookupTyVar name
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- returnNF_Tc (lookupWithDefaultUFM tve (pprPanic "tcLookupTyVar:" (ppr name)) name)
-
-
-tcLookupTyCon name
- = -- Try for a wired-in tycon
- case maybeWiredInTyConName name of {
- Just tc | isSynTyCon tc -> returnTc (kind, Just (tyConArity tc), tc)
- | otherwise -> returnTc (kind, Nothing, tc)
- where {
- kind = kindToTcKind (tyConKind tc)
- };
-
- Nothing ->
-
- -- Try in the environment
- tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- case lookupUFM tce name of {
- Just stuff -> returnTc stuff;
-
- Nothing ->
-
- -- Could be that he's using a class name as a type constructor
- case lookupUFM ce name of
- Just _ -> failWithTc (classAsTyConErr name)
- Nothing -> pprPanic "tcLookupTyCon:" (ppr name)
- } }
-
-tcLookupTyConByKey uniq
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- let
- (kind, arity, tycon) = lookupWithDefaultUFM_Directly tce
- (pprPanic "tcLookupTyConByKey:" (pprUnique10 uniq))
- uniq
+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
in
- returnNF_Tc tycon
-
-tcLookupClass name
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- case lookupUFM ce name of
- Just stuff -- Common case: it's ok
- -> returnTc stuff
-
- Nothing -- Could be that he's using a type constructor as a class
- | maybeToBool (maybeWiredInTyConName name)
- || maybeToBool (lookupUFM tce name)
- -> failWithTc (tyConAsClassErr name)
-
- | otherwise -- Wierd! Renamer shouldn't let this happen
- -> pprPanic "tcLookupClass" (ppr name)
+ tc_extend_gtvs (tcl_tyvars env) extra_global_tyvars `thenM` \ gtvs' ->
+ setLclEnv (env {tcl_env = le', tcl_tyvars = gtvs'}) thing_inside
-tcLookupClassByKey uniq
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
+tcExtendLocalValEnv2 :: [(Name,TcId)] -> TcM a -> TcM a
+tcExtendLocalValEnv2 names_w_ids thing_inside
+ = getLclEnv `thenM` \ env ->
let
- (kind, clas) = lookupWithDefaultUFM_Directly ce
- (pprPanic "tcLookupClassByKey:" (pprUnique10 uniq))
- uniq
+ 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]
+ le' = extendNameEnvList (tcl_env env) extra_env
in
- returnNF_Tc clas
-
-tcGetTyConsAndClasses :: NF_TcM s ([TyCon], [Class])
-tcGetTyConsAndClasses
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- returnNF_Tc ([tc | (_, _, tc) <- eltsUFM tce],
- [c | (_, c) <- eltsUFM ce])
+ tc_extend_gtvs (tcl_tyvars env) extra_global_tyvars `thenM` \ gtvs' ->
+ setLclEnv (env {tcl_env = le', tcl_tyvars = gtvs'}) thing_inside
\end{code}
-
-Extending and consulting the value environment
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
\begin{code}
-tcExtendGlobalValEnv ids scope
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- let
- gve' = addListToUFM_Directly gve [(uniqueOf id, id) | id <- ids]
+-----------------------
+-- findGlobals looks at the value environment and finds values
+-- whose types mention the offending type variable. It has to be
+-- careful to zonk the Id's type first, so it has to be in the monad.
+-- We must be careful to pass it a zonked type variable, too.
+
+findGlobals :: TcTyVarSet
+ -> TidyEnv
+ -> TcM (TidyEnv, [SDoc])
+
+findGlobals tvs tidy_env
+ = getLclEnv `thenM` \ lcl_env ->
+ go tidy_env [] (lclEnvElts lcl_env)
+ where
+ go tidy_env acc [] = returnM (tidy_env, acc)
+ go tidy_env acc (thing : things)
+ = find_thing ignore_it tidy_env thing `thenM` \ (tidy_env1, maybe_doc) ->
+ case maybe_doc of
+ Just d -> go tidy_env1 (d:acc) things
+ Nothing -> go tidy_env1 acc things
+
+ ignore_it ty = not (tvs `intersectsVarSet` tyVarsOfType ty)
+
+-----------------------
+find_thing ignore_it tidy_env (ATcId id _ _)
+ = zonkTcType (idType id) `thenM` \ id_ty ->
+ if ignore_it id_ty then
+ returnM (tidy_env, Nothing)
+ else let
+ (tidy_env', tidy_ty) = tidyOpenType tidy_env id_ty
+ msg = sep [ppr id <+> dcolon <+> ppr tidy_ty,
+ nest 2 (parens (ptext SLIT("bound at") <+>
+ ppr (getSrcLoc id)))]
in
- tcSetEnv (TcEnv tve tce ce gve' lve gtvs) scope
-
-tcExtendLocalValEnv names ids scope
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- tcReadMutVar gtvs `thenNF_Tc` \ global_tvs ->
- let
- lve' = addListToUFM lve (zipEqual "tcExtendLocalValEnv" names ids)
- extra_global_tyvars = tyVarsOfTypes (map idType ids)
- new_global_tyvars = global_tvs `unionTyVarSets` extra_global_tyvars
+ returnM (tidy_env', Just msg)
+
+find_thing ignore_it tidy_env (ATyVar tv)
+ = zonkTcTyVar tv `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]
+
+ eq_stuff | Just tv' <- Type.getTyVar_maybe tv_ty, tv == tv' = empty
+ | otherwise = equals <+> ppr tv_ty
+ -- It's ok to use Type.getTyVar_maybe because ty is zonked by now
+
+ bound_at = tyVarBindingInfo tv
in
- tcNewMutVar new_global_tyvars `thenNF_Tc` \ gtvs' ->
+ returnM (tidy_env2, Just msg)
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{The global tyvars}
+%* *
+%************************************************************************
- tcSetEnv (TcEnv tve tce ce gve lve' gtvs') scope
+\begin{code}
+tc_extend_gtvs gtvs extra_global_tvs
+ = readMutVar gtvs `thenM` \ global_tvs ->
+ newMutVar (global_tvs `unionVarSet` extra_global_tvs)
\end{code}
@tcGetGlobalTyVars@ returns a fully-zonked set of tyvars free in the environment.
the environment.
\begin{code}
-tcGetGlobalTyVars :: NF_TcM s (TcTyVarSet s)
+tcGetGlobalTyVars :: TcM TcTyVarSet
tcGetGlobalTyVars
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- tcReadMutVar gtvs `thenNF_Tc` \ global_tvs ->
- zonkTcTyVars global_tvs `thenNF_Tc` \ global_tvs' ->
- tcWriteMutVar gtvs global_tvs' `thenNF_Tc_`
- returnNF_Tc global_tvs'
-
-tcExtendGlobalTyVars extra_global_tvs scope
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- tcReadMutVar gtvs `thenNF_Tc` \ global_tvs ->
- let
- new_global_tyvars = global_tvs `unionTyVarSets` mkTyVarSet extra_global_tvs
- in
- tcNewMutVar new_global_tyvars `thenNF_Tc` \ gtvs' ->
- tcSetEnv (TcEnv tve tce ce gve lve gtvs') scope
+ = getLclEnv `thenM` \ (TcLclEnv {tcl_tyvars = gtv_var}) ->
+ readMutVar gtv_var `thenM` \ gbl_tvs ->
+ zonkTcTyVarsAndFV (varSetElems gbl_tvs) `thenM` \ gbl_tvs' ->
+ writeMutVar gtv_var gbl_tvs' `thenM_`
+ returnM gbl_tvs'
\end{code}
-\begin{code}
-tcLookupLocalValue :: Name -> NF_TcM s (Maybe (TcIdBndr s))
-tcLookupLocalValue name
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- returnNF_Tc (lookupUFM lve name)
-
-tcLookupLocalValueByKey :: Unique -> NF_TcM s (Maybe (TcIdBndr s))
-tcLookupLocalValueByKey uniq
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- returnNF_Tc (lookupUFM_Directly lve uniq)
-
-tcLookupLocalValueOK :: String -> Name -> NF_TcM s (TcIdBndr s)
-tcLookupLocalValueOK err name
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- returnNF_Tc (lookupWithDefaultUFM lve (panic err) name)
-
-
-tcLookupGlobalValue :: Name -> NF_TcM s Id
-tcLookupGlobalValue name
- = case maybeWiredInIdName name of
- Just id -> returnNF_Tc id
- Nothing -> tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- returnNF_Tc (lookupWithDefaultUFM gve def name)
- where
- def = pprPanic "tcLookupGlobalValue:" (ppr name)
-tcLookupGlobalValueMaybe :: Name -> NF_TcM s (Maybe Id)
-tcLookupGlobalValueMaybe name
- = case maybeWiredInIdName name of
- Just id -> returnNF_Tc (Just id)
- Nothing -> tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- returnNF_Tc (lookupUFM gve name)
+%************************************************************************
+%* *
+\subsection{The instance environment}
+%* *
+%************************************************************************
+The TcGblEnv holds a mutable variable containing the current full, instance environment.
+The ExtendInstEnv functions extend this environment by side effect, in case we are
+sucking in new instance declarations deep in the body of a TH splice, which are needed
+in another TH splice. The tcg_insts field of the TcGblEnv contains just the dfuns
+from this module
-tcLookupGlobalValueByKey :: Unique -> NF_TcM s Id
-tcLookupGlobalValueByKey uniq
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- returnNF_Tc (lookupWithDefaultUFM_Directly gve def uniq)
+\begin{code}
+tcGetInstEnv :: TcM InstEnv
+tcGetInstEnv = do { env <- getGblEnv; readMutVar (tcg_inst_env env) }
+
+tcExtendInstEnv :: [DFunId] -> TcM a -> TcM a
+ -- Add instances from local or imported
+ -- instances, and refresh the instance-env cache
+tcExtendInstEnv dfuns thing_inside
+ = do { dflags <- getDOpts
+ ; eps <- getEps
+ ; env <- getGblEnv
+ ; let ie_var = tcg_inst_env env
+ ; inst_env <- readMutVar ie_var
+ ; let
+ -- Extend the total inst-env with the new dfuns
+ (inst_env', errs) = extendInstEnv dflags inst_env dfuns
+
+ -- Sort the ones from this module from the others
+ (lcl_dfuns, pkg_dfuns) = partition (isLocalThing mod) dfuns
+ mod = tcg_mod env
+
+ -- And add the pieces to the right places
+ (eps_inst_env', _) = extendInstEnv dflags (eps_inst_env eps) pkg_dfuns
+ eps' = eps { eps_inst_env = eps_inst_env' }
+
+ env' = env { tcg_insts = lcl_dfuns ++ tcg_insts env }
+
+ ; traceDFuns dfuns
+ ; addErrs errs
+ ; writeMutVar ie_var inst_env'
+ ; setEps eps'
+ ; setGblEnv env' thing_inside }
+
+tcExtendLocalInstEnv :: [InstInfo] -> TcM a -> TcM a
+ -- Special case for local instance decls
+tcExtendLocalInstEnv infos thing_inside
+ = do { dflags <- getDOpts
+ ; env <- getGblEnv
+ ; let ie_var = tcg_inst_env env
+ ; inst_env <- readMutVar ie_var
+ ; let
+ dfuns = map iDFunId infos
+ (inst_env', errs) = extendInstEnv dflags inst_env dfuns
+ env' = env { tcg_insts = dfuns ++ tcg_insts env }
+ ; traceDFuns dfuns
+ ; addErrs errs
+ ; writeMutVar ie_var inst_env'
+ ; setGblEnv env' thing_inside }
+
+tcExtendTempInstEnv :: [DFunId] -> TcM a -> TcM a
+ -- Extend the instance envt, but with *no* permanent
+ -- effect on mutable variables; also ignore errors
+ -- Used during 'deriving' stuff
+tcExtendTempInstEnv dfuns thing_inside
+ = do { dflags <- getDOpts
+ ; env <- getGblEnv
+ ; let ie_var = tcg_inst_env env
+ ; inst_env <- readMutVar ie_var
+ ; let (inst_env', errs) = extendInstEnv dflags inst_env dfuns
+ -- Ignore the errors about duplicate instances.
+ -- We don't want repeated error messages
+ -- They'll appear later, when we do the top-level extendInstEnvs
+ ; writeMutVar ie_var inst_env'
+ ; result <- thing_inside
+ ; writeMutVar ie_var inst_env -- Restore!
+ ; return result }
+
+tcWithTempInstEnv :: TcM a -> TcM a
+-- Run thing_inside, discarding any effects on the instance environment
+tcWithTempInstEnv thing_inside
+ = do { env <- getGblEnv
+ ; let ie_var = tcg_inst_env env
+ ; old_ie <- readMutVar ie_var
+ ; result <- thing_inside
+ ; writeMutVar ie_var old_ie -- Restore
+ ; return result }
+
+traceDFuns dfuns
+ = traceTc (text "Adding instances:" <+> vcat (map pp dfuns))
where
-#ifdef DEBUG
- def = pprPanic "tcLookupGlobalValueByKey:" (pprUnique10 uniq)
-#else
- def = panic "tcLookupGlobalValueByKey"
-#endif
-
-tcLookupGlobalValueByKeyMaybe :: Unique -> NF_TcM s (Maybe Id)
-tcLookupGlobalValueByKeyMaybe uniq
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- returnNF_Tc (lookupUFM_Directly gve uniq)
+ pp dfun = ppr dfun <+> dcolon <+> ppr (idType dfun)
+\end{code}
--- Non-monadic version, environment given explicitly
-tcExplicitLookupGlobal :: TcEnv s -> Name -> Maybe Id
-tcExplicitLookupGlobal (TcEnv tve tce ce gve lve gtvs) name
- = case maybeWiredInIdName name of
- Just id -> Just id
- Nothing -> lookupUFM gve name
+%************************************************************************
+%* *
+\subsection{Rules}
+%* *
+%************************************************************************
- -- Extract the IdInfo from an IfaceSig imported from an interface file
-tcAddImportedIdInfo :: TcEnv s -> Id -> Id
-tcAddImportedIdInfo unf_env id
- | isLocallyDefined id -- Don't look up locally defined Ids, because they
- -- have explicit local definitions, so we get a black hole!
- = id
- | otherwise
- = id `replaceIdInfo` new_info
- -- The Id must be returned without a data dependency on maybe_id
- where
- new_info = -- pprTrace "tcAdd" (ppr id) $
- case tcExplicitLookupGlobal unf_env (getName id) of
- Nothing -> noIdInfo
- Just imported_id -> getIdInfo imported_id
- -- ToDo: could check that types are the same
+\begin{code}
+tcExtendRules :: [RuleDecl Id] -> TcM a -> TcM a
+ -- Just pop the new rules into the EPS and envt resp
+ -- All the rules come from an interface file, not soruce
+ -- Nevertheless, some may be for this module, if we read
+ -- its interface instead of its source code
+tcExtendRules rules thing_inside
+ = do { eps <- getEps
+ ; env <- getGblEnv
+ ; let
+ (lcl_rules, pkg_rules) = partition is_local_rule rules
+ is_local_rule = isLocalThing mod . ifaceRuleDeclName
+ mod = tcg_mod env
+
+ core_rules = [(id,rule) | IfaceRuleOut id rule <- pkg_rules]
+ eps' = eps { eps_rule_base = addIfaceRules (eps_rule_base eps) core_rules }
+ -- All the rules from an interface are of the IfaceRuleOut form
+
+ env' = env { tcg_rules = lcl_rules ++ tcg_rules env }
+
+ ; setEps eps'
+ ; setGblEnv env' thing_inside }
+
+addIfaceRules :: RuleBase -> [IdCoreRule] -> RuleBase
+addIfaceRules rule_base rules
+ = foldl extendRuleBase rule_base rules
\end{code}
-Constructing new Ids
-~~~~~~~~~~~~~~~~~~~~
+%************************************************************************
+%* *
+\subsection{The InstInfo type}
+%* *
+%************************************************************************
-\begin{code}
--- Uses the Name as the Name of the Id
-newMonoIds :: [Name] -> Kind -> ([TcIdBndr s] -> TcM s a) -> TcM s a
+The InstInfo type summarises the information in an instance declaration
-newMonoIds names kind m
- = newTyVarTys no_of_names kind `thenNF_Tc` \ tys ->
- let
- new_ids = zipWithEqual "newMonoIds" mk_id names tys
- mk_id name ty = mkUserId name ty
- in
- tcExtendLocalValEnv names new_ids (m new_ids)
- where
- no_of_names = length names
-
-newLocalId :: OccName -> TcType s -> NF_TcM s (TcIdBndr s)
-newLocalId name ty
- = tcGetSrcLoc `thenNF_Tc` \ loc ->
- tcGetUnique `thenNF_Tc` \ uniq ->
- returnNF_Tc (mkUserLocal name uniq ty loc)
-
-newLocalIds :: [OccName] -> [TcType s] -> NF_TcM s [TcIdBndr s]
-newLocalIds names tys
- = tcGetSrcLoc `thenNF_Tc` \ loc ->
- tcGetUniques (length names) `thenNF_Tc` \ uniqs ->
- let
- new_ids = zipWith3Equal "newLocalIds" mk_id names uniqs tys
- mk_id name uniq ty = mkUserLocal name uniq ty loc
- in
- returnNF_Tc new_ids
+ instance c => k (t tvs) where b
+
+It is used just for *local* instance decls (not ones from interface files).
+But local instance decls includes
+ - derived ones
+ - generic ones
+as well as explicit user written ones.
+
+\begin{code}
+data InstInfo
+ = InstInfo {
+ iDFunId :: DFunId, -- The dfun id
+ iBinds :: InstBindings
+ }
+
+data InstBindings
+ = VanillaInst -- The normal case
+ RenamedMonoBinds -- Bindings
+ [RenamedSig] -- User pragmas recorded for generating
+ -- specialised instances
+
+ | NewTypeDerived -- Used for deriving instances of newtypes, where the
+ [Type] -- witness dictionary is identical to the argument
+ -- dictionary. Hence no bindings, no pragmas
+ -- The [Type] are the representation types
+ -- See notes in TcDeriv
+
+pprInstInfo info = vcat [ptext SLIT("InstInfo:") <+> ppr (idType (iDFunId info))]
+
+pprInstInfoDetails (InstInfo { iBinds = VanillaInst b _ }) = ppr b
+pprInstInfoDetails (InstInfo { iBinds = NewTypeDerived _}) = text "Derived from the representation type"
+
+simpleInstInfoTy :: InstInfo -> Type
+simpleInstInfoTy info = case tcSplitDFunTy (idType (iDFunId info)) of
+ (_, _, _, [ty]) -> ty
+
+simpleInstInfoTyCon :: InstInfo -> TyCon
+ -- Gets the type constructor for a simple instance declaration,
+ -- i.e. one of the form instance (...) => C (T a b c) where ...
+simpleInstInfoTyCon inst = tcTyConAppTyCon (simpleInstInfoTy inst)
\end{code}
+%************************************************************************
+%* *
+\subsection{Errors}
+%* *
+%************************************************************************
+
\begin{code}
-classAsTyConErr name
- = ptext SLIT("Class used as a type constructor:") <+> ppr name
+badCon con_id = quotes (ppr con_id) <+> ptext SLIT("is not a data constructor")
-tyConAsClassErr name
- = ptext SLIT("Type constructor used as a class:") <+> ppr name
+notFound wheRe name = failWithTc (text wheRe <> colon <+> quotes (ppr name) <+>
+ ptext SLIT("is not in scope"))
\end{code}
projects / ghc-hetmet.git / blobdiff