\begin{code}
-#include "HsVersions.h"
-
module TcEnv(
- TcEnv,
+ TcId, TcIdSet,
+ TyThing(..), TyThingDetails(..), TcTyThing(..),
- initEnv, getEnv_LocalIds, getEnv_TyCons, getEnv_Classes,
+ -- Getting stuff from the environment
+ TcEnv, initTcEnv,
+ tcEnvTyCons, tcEnvClasses, tcEnvIds, tcLEnvElts,
+ getTcGEnv,
- tcTyVarScope, tcTyVarScopeGivenKinds, tcLookupTyVar,
+ -- Instance environment, and InstInfo type
+ tcGetInstEnv, tcSetInstEnv,
+ InstInfo(..), pprInstInfo,
+ simpleInstInfoTy, simpleInstInfoTyCon,
+
+ -- Global environment
+ tcExtendGlobalEnv, tcExtendGlobalValEnv, tcExtendGlobalTypeEnv,
+ tcLookupTyCon, tcLookupClass, tcLookupGlobalId, tcLookupDataCon,
+ tcLookupGlobal_maybe, tcLookupGlobal,
+
+ -- Local environment
+ tcExtendKindEnv, tcLookupLocalIds, tcInLocalScope,
+ tcExtendTyVarEnv, tcExtendTyVarEnvForMeths,
+ tcExtendLocalValEnv, tcLookup, tcLookup_maybe, tcLookupId,
- tcExtendTyConEnv, tcLookupTyCon, tcLookupTyConByKey,
- tcExtendClassEnv, tcLookupClass, tcLookupClassByKey,
- tcGetTyConsAndClasses,
+ -- Global type variables
+ tcGetGlobalTyVars, tcExtendGlobalTyVars,
- tcExtendGlobalValEnv, tcExtendLocalValEnv,
- tcLookupLocalValue, tcLookupLocalValueOK, tcLookupLocalValueByKey,
- tcLookupGlobalValue, tcLookupGlobalValueByKey,
+ -- Random useful things
+ RecTcEnv, tcLookupRecId, tcLookupRecId_maybe,
- newMonoIds, newLocalIds, newLocalId,
- tcGetGlobalTyVars, tcExtendGlobalTyVars
+ -- New Ids
+ newLocalName, newDFunName,
+
+ -- Misc
+ isLocalThing, tcSetEnv
) where
+#include "HsVersions.h"
-IMP_Ubiq()
-IMPORT_DELOOPER(TcMLoop) -- for paranoia checking
-
-import Id ( SYN_IE(Id), GenId, idType, mkUserLocal )
-import TcHsSyn ( TcIdBndr(..), TcIdOcc(..) )
-import TcKind ( TcKind, newKindVars, tcDefaultKind, kindToTcKind )
-import TcType ( TcType(..), TcMaybe, TcTyVar(..), TcTyVarSet(..),
- newTyVarTys, tcInstTyVars, zonkTcTyVars
- )
-import TyVar ( mkTyVar, tyVarKind, unionTyVarSets, emptyTyVarSet )
-import Type ( tyVarsOfTypes )
-import TyCon ( TyCon, tyConKind, synTyConArity )
-import Class ( SYN_IE(Class), GenClass, classSig )
-
-import TcMonad hiding ( rnMtoTcM )
-
-import Name ( getOccName, getSrcLoc, Name{-instance NamedThing-} )
-import PprStyle
-import Pretty
-import RnHsSyn ( RnName(..) )
-import Type ( splitForAllTy )
-import Unique ( pprUnique10, pprUnique{-ToDo:rm-} )
-import UniqFM
-import Util ( zipEqual, zipWithEqual, zipWith3Equal, zipLazy,
- panic, pprPanic, pprTrace{-ToDo:rm-}
+import RnHsSyn ( RenamedMonoBinds, RenamedSig )
+import TcMonad
+import TcMType ( zonkTcTyVarsAndFV )
+import TcType ( Type, ThetaType, TcKind, TcTyVar, TcTyVarSet,
+ tyVarsOfTypes, tcSplitDFunTy,
+ getDFunTyKey, tcTyConAppTyCon
+ )
+import Id ( idName, isDataConWrapId_maybe )
+import IdInfo ( vanillaIdInfo )
+import Var ( TyVar, Id, idType, lazySetIdInfo, idInfo )
+import VarSet
+import DataCon ( DataCon )
+import TyCon ( TyCon )
+import Class ( Class, ClassOpItem )
+import Name ( Name, NamedThing(..),
+ getSrcLoc, mkLocalName, isLocalName, nameIsLocalOrFrom
)
+import NameEnv ( NameEnv, lookupNameEnv, nameEnvElts, elemNameEnv,
+ extendNameEnvList, emptyNameEnv, plusNameEnv )
+import OccName ( mkDFunOcc, occNameString )
+import HscTypes ( DFunId,
+ PackageTypeEnv, TypeEnv,
+ extendTypeEnvList, extendTypeEnvWithIds,
+ typeEnvTyCons, typeEnvClasses, typeEnvIds,
+ HomeSymbolTable
+ )
+import Module ( Module )
+import InstEnv ( InstEnv, emptyInstEnv )
+import HscTypes ( lookupType, TyThing(..) )
+import Util ( zipEqual )
+import SrcLoc ( SrcLoc )
+import Outputable
+
+import IOExts ( newIORef )
\end{code}
-Data type declarations
-~~~~~~~~~~~~~~~~~~~~~
+%************************************************************************
+%* *
+\subsection{TcEnv}
+%* *
+%************************************************************************
\begin{code}
-data TcEnv s = TcEnv
- (TyVarEnv s)
- (TyConEnv s)
- (ClassEnv s)
- (ValueEnv Id) -- Globals
- (ValueEnv (TcIdBndr s)) -- Locals
- (MutableVar 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)
-type ValueEnv id = UniqFM id
-
-initEnv :: MutableVar 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]
+type TcId = Id -- Type may be a TcType
+type TcIdSet = IdSet
+
+data TcEnv
+ = TcEnv {
+ tcGST :: Name -> Maybe TyThing, -- The type environment at the moment we began this compilation
+
+ tcInsts :: InstEnv, -- All instances (both imported and in this module)
+
+ tcGEnv :: TypeEnv, -- The global type environment we've accumulated while
+ {- NameEnv TyThing-} -- compiling this module:
+ -- types and classes (both imported and local)
+ -- imported Ids
+ -- (Ids defined in this module start in the local envt,
+ -- though they move to the global envt during zonking)
+
+ tcLEnv :: NameEnv TcTyThing, -- The local type environment: Ids and TyVars
+ -- defined in this module
+
+ tcTyVars :: TcRef TcTyVarSet -- The "global tyvars"
+ -- Namely, the in-scope TyVars bound in tcLEnv, plus the tyvars
+ -- mentioned in the types of Ids bound in tcLEnv
+ -- Why mutable? see notes with tcGetGlobalTyVars
+ }
+
\end{code}
-Making new TcTyVars, with knot tying!
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+The Global-Env/Local-Env story
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+During type checking, we keep in the GlobalEnv
+ * All types and classes
+ * All Ids derived from types and classes (constructors, selectors)
+ * Imported Ids
+
+At the end of type checking, we zonk the local bindings,
+and as we do so we add to the GlobalEnv
+ * Locally defined top-level Ids
+
+Why? Because they are now Ids not TcIds. This final GlobalEnv is
+used thus:
+ a) fed back (via the knot) to typechecking the
+ unfoldings of interface signatures
+
+ b) used to augment the GlobalSymbolTable
+
+
\begin{code}
-tcTyVarScopeGivenKinds
- :: [Name] -- Names of some type variables
- -> [TcKind s]
- -> ([TyVar] -> TcM s a) -- Thing to type check in their scope
- -> TcM s a -- Result
-
-tcTyVarScopeGivenKinds names kinds thing_inside
- = fixTc (\ ~(rec_tyvars, _) ->
- -- Ok to look at names, kinds, but not tyvars!
-
- tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- let
- tve' = addListToUFM tve (zipEqual "tcTyVarScopeGivenKinds" names (kinds `zipLazy` rec_tyvars))
- in
- tcSetEnv (TcEnv tve' tce ce gve lve gtvs)
- (thing_inside rec_tyvars) `thenTc` \ result ->
-
- -- Get the tyvar's Kinds from their TcKinds
- mapNF_Tc tcDefaultKind kinds `thenNF_Tc` \ kinds' ->
-
- -- Construct the real TyVars
- let
- tyvars = zipWithEqual "tcTyVarScopeGivenKinds" mkTyVar names kinds'
- in
- returnTc (tyvars, result)
- ) `thenTc` \ (_,result) ->
- returnTc result
-
-tcTyVarScope names thing_inside
- = newKindVars (length names) `thenNF_Tc` \ kinds ->
- tcTyVarScopeGivenKinds names kinds thing_inside
+initTcEnv :: HomeSymbolTable -> PackageTypeEnv -> IO TcEnv
+initTcEnv hst pte
+ = do { gtv_var <- newIORef emptyVarSet ;
+ return (TcEnv { tcGST = lookup,
+ tcGEnv = emptyNameEnv,
+ tcInsts = emptyInstEnv,
+ tcLEnv = emptyNameEnv,
+ tcTyVars = gtv_var
+ })}
+ where
+ lookup name | isLocalName name = Nothing
+ | otherwise = lookupType hst pte name
+
+
+tcEnvClasses env = typeEnvClasses (tcGEnv env)
+tcEnvTyCons env = typeEnvTyCons (tcGEnv env)
+tcEnvIds env = typeEnvIds (tcGEnv env)
+tcLEnvElts env = nameEnvElts (tcLEnv env)
+
+getTcGEnv (TcEnv { tcGEnv = genv }) = genv
+
+tcInLocalScope :: TcEnv -> Name -> Bool
+tcInLocalScope env v = v `elemNameEnv` (tcLEnv env)
\end{code}
+\begin{code}
+data TcTyThing
+ = AGlobal TyThing -- Used only in the return type of a lookup
+ | ATcId TcId -- Ids defined in this module
+ | ATyVar TyVar -- Type variables
+ | AThing TcKind -- Used temporarily, during kind checking
+-- Here's an example of how the AThing guy is used
+-- Suppose we are checking (forall a. T a Int):
+-- 1. We first bind (a -> AThink kv), where kv is a kind variable.
+-- 2. Then we kind-check the (T a Int) part.
+-- 3. Then we zonk the kind variable.
+-- 4. Now we know the kind for 'a', and we add (a -> ATyVar a::K) to the environment
-The Kind, TyVar, Class and TyCon envs
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+\end{code}
-Extending the environments. Notice the uses of @zipLazy@, which makes sure
-that the knot-tied TyVars, TyCons and Classes aren't looked at too early.
+This data type is used to help tie the knot
+ when type checking type and class declarations
\begin{code}
-tcExtendTyConEnv :: [(RnName,Maybe Arity)] -> [TyCon] -> TcM s r -> TcM s r
+data TyThingDetails = SynTyDetails Type
+ | DataTyDetails ThetaType [DataCon] [Id]
+ | ClassDetails ThetaType [Id] [ClassOpItem] DataCon
+ | ForeignTyDetails -- Nothing yet
+\end{code}
-tcExtendTyConEnv names_w_arities tycons scope
- = newKindVars (length names_w_arities) `thenNF_Tc` \ kinds ->
- tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- let
- tce' = addListToUFM tce [ (name, (kind, arity, tycon))
- | ((name,arity), (kind,tycon))
- <- zipEqual "tcExtendTyConEnv" names_w_arities (kinds `zipLazy` tycons)
- ]
- in
- tcSetEnv (TcEnv tve tce' ce gve lve gtvs) scope `thenTc` \ result ->
- mapNF_Tc tcDefaultKind kinds `thenNF_Tc_`
- returnTc result
+%************************************************************************
+%* *
+\subsection{Basic lookups}
+%* *
+%************************************************************************
+\begin{code}
+lookup_global :: TcEnv -> Name -> Maybe TyThing
+ -- Try the global envt and then the global symbol table
+lookup_global env name
+ = case lookupNameEnv (tcGEnv env) name of
+ Just thing -> Just thing
+ Nothing -> tcGST env name
+
+lookup_local :: TcEnv -> Name -> Maybe TcTyThing
+ -- Try the local envt and then try the global
+lookup_local env name
+ = case lookupNameEnv (tcLEnv env) name of
+ Just thing -> Just thing
+ Nothing -> case lookup_global env name of
+ Just thing -> Just (AGlobal thing)
+ Nothing -> Nothing
+\end{code}
-tcExtendClassEnv :: [RnName] -> [Class] -> TcM s r -> TcM s r
-tcExtendClassEnv names classes scope
- = newKindVars (length names) `thenNF_Tc` \ kinds ->
- tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- let
- ce' = addListToUFM ce (zipEqual "tcExtendClassEnv" names (kinds `zipLazy` classes))
- in
- tcSetEnv (TcEnv tve tce ce' gve lve gtvs) scope `thenTc` \ result ->
- mapNF_Tc tcDefaultKind kinds `thenNF_Tc_`
- returnTc result
+\begin{code}
+type RecTcEnv = TcEnv
+-- This environment is used for getting the 'right' IdInfo
+-- on imported things and for looking up Ids in unfoldings
+-- The environment doesn't have any local Ids in it
+
+tcLookupRecId_maybe :: RecTcEnv -> Name -> Maybe Id
+tcLookupRecId_maybe env name = case lookup_global env name of
+ Just (AnId id) -> Just id
+ other -> Nothing
+
+tcLookupRecId :: RecTcEnv -> Name -> Id
+tcLookupRecId env name = case lookup_global env name of
+ Just (AnId id) -> id
+ Nothing -> pprPanic "tcLookupRecId" (ppr name)
\end{code}
+%************************************************************************
+%* *
+\subsection{Making new Ids}
+%* *
+%************************************************************************
+
+Constructing new Ids
+
+\begin{code}
+newLocalName :: Name -> NF_TcM Name
+newLocalName name -- Make a clone
+ = tcGetUnique `thenNF_Tc` \ uniq ->
+ returnNF_Tc (mkLocalName uniq (getOccName name) (getSrcLoc name))
+\end{code}
-Looking up in the environments.
+Make a name for the dict fun for an instance decl.
+It's a *local* name for the moment. The CoreTidy pass
+will globalise it.
\begin{code}
-tcLookupTyVar name
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- returnNF_Tc (lookupWithDefaultUFM tve (pprPanic "tcLookupTyVar:" (ppr PprShowAll name)) name)
+newDFunName :: Class -> [Type] -> SrcLoc -> NF_TcM Name
+newDFunName clas (ty:_) loc
+ = tcGetUnique `thenNF_Tc` \ uniq ->
+ returnNF_Tc (mkLocalName 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}
+
+\begin{code}
+isLocalThing :: NamedThing a => Module -> a -> Bool
+isLocalThing mod thing = nameIsLocalOrFrom mod (getName thing)
+\end{code}
-tcLookupTyCon (WiredInTyCon tc) -- wired in tycons
- = returnNF_Tc (kindToTcKind (tyConKind tc), synTyConArity tc, tc)
+%************************************************************************
+%* *
+\subsection{The global environment}
+%* *
+%************************************************************************
-tcLookupTyCon name
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- returnNF_Tc (lookupWithDefaultUFM tce (pprPanic "tcLookupTyCon:" (ppr PprShowAll name)) name)
-
-tcLookupTyConByKey uniq
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- let
- (kind, arity, tycon) = lookupWithDefaultUFM_Directly tce
- (pprPanic "tcLookupTyCon:" (pprUnique10 uniq))
- uniq
+\begin{code}
+tcExtendGlobalEnv :: [TyThing] -> TcM r -> TcM r
+tcExtendGlobalEnv things thing_inside
+ = tcGetEnv `thenNF_Tc` \ env ->
+ let
+ ge' = extendTypeEnvList (tcGEnv env) things
in
- returnNF_Tc tycon
+ tcSetEnv (env {tcGEnv = ge'}) thing_inside
-tcLookupClass name
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
--- pprTrace "tcLookupClass:" (ppCat [ppStr "Uniq:", pprUnique10 (uniqueOf name), ppStr "; avail:", ppCat (map (pprUnique10 . fst) (ufmToList ce))]) $
--- pprTrace "tcLookupClass:" (ppCat [ppStr "Uniq:", pprUnique (uniqueOf name), ppStr "; avail:", ppCat (map (pprUnique . fst) (ufmToList ce))]) $
- returnNF_Tc (lookupWithDefaultUFM ce (pprPanic "tcLookupClass:" (ppr PprShowAll name)) name)
-tcLookupClassByKey uniq
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
+tcExtendGlobalTypeEnv :: TypeEnv -> TcM r -> TcM r
+tcExtendGlobalTypeEnv extra_env thing_inside
+ = tcGetEnv `thenNF_Tc` \ env ->
let
- (kind, clas) = lookupWithDefaultUFM_Directly ce
- (pprPanic "tcLookupClassByKey:" (pprUnique10 uniq))
- uniq
+ ge' = tcGEnv env `plusNameEnv` extra_env
in
- returnNF_Tc clas
+ tcSetEnv (env {tcGEnv = ge'}) thing_inside
-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])
+tcExtendGlobalValEnv :: [Id] -> TcM a -> TcM a
+tcExtendGlobalValEnv ids thing_inside
+ = tcGetEnv `thenNF_Tc` \ env ->
+ let
+ ge' = extendTypeEnvWithIds (tcGEnv env) ids
+ in
+ tcSetEnv (env {tcGEnv = ge'}) thing_inside
+\end{code}
+
+
+\begin{code}
+tcLookupGlobal_maybe :: Name -> NF_TcM (Maybe TyThing)
+tcLookupGlobal_maybe name
+ = tcGetEnv `thenNF_Tc` \ env ->
+ returnNF_Tc (lookup_global env name)
+\end{code}
+
+A variety of global lookups, when we know what we are looking for.
+
+\begin{code}
+tcLookupGlobal :: Name -> NF_TcM TyThing
+tcLookupGlobal name
+ = tcLookupGlobal_maybe name `thenNF_Tc` \ maybe_thing ->
+ case maybe_thing of
+ Just thing -> returnNF_Tc thing
+ other -> notFound "tcLookupGlobal" name
+
+tcLookupGlobalId :: Name -> NF_TcM Id
+tcLookupGlobalId name
+ = tcLookupGlobal_maybe name `thenNF_Tc` \ maybe_id ->
+ case maybe_id of
+ Just (AnId id) -> returnNF_Tc id
+ other -> notFound "tcLookupGlobalId" name
+
+tcLookupDataCon :: Name -> TcM DataCon
+tcLookupDataCon con_name
+ = tcLookupGlobalId con_name `thenNF_Tc` \ con_id ->
+ case isDataConWrapId_maybe con_id of
+ Just data_con -> returnTc data_con
+ Nothing -> failWithTc (badCon con_id)
+
+
+tcLookupClass :: Name -> NF_TcM Class
+tcLookupClass name
+ = tcLookupGlobal_maybe name `thenNF_Tc` \ maybe_clas ->
+ case maybe_clas of
+ Just (AClass clas) -> returnNF_Tc clas
+ other -> notFound "tcLookupClass" name
+
+tcLookupTyCon :: Name -> NF_TcM TyCon
+tcLookupTyCon name
+ = tcLookupGlobal_maybe name `thenNF_Tc` \ maybe_tc ->
+ case maybe_tc of
+ Just (ATyCon tc) -> returnNF_Tc tc
+ other -> notFound "tcLookupTyCon" name
+
+tcLookupId :: Name -> NF_TcM Id
+tcLookupId name
+ = tcLookup name `thenNF_Tc` \ thing ->
+ case thing of
+ ATcId tc_id -> returnNF_Tc tc_id
+ AGlobal (AnId id) -> returnNF_Tc id
+ other -> pprPanic "tcLookupId" (ppr name)
+
+tcLookupLocalIds :: [Name] -> NF_TcM [TcId]
+tcLookupLocalIds ns
+ = tcGetEnv `thenNF_Tc` \ env ->
+ returnNF_Tc (map (lookup (tcLEnv env)) ns)
+ where
+ lookup lenv name = case lookupNameEnv lenv name of
+ Just (ATcId id) -> id
+ other -> pprPanic "tcLookupLocalIds" (ppr name)
\end{code}
+%************************************************************************
+%* *
+\subsection{The local environment}
+%* *
+%************************************************************************
+
+\begin{code}
+tcLookup_maybe :: Name -> NF_TcM (Maybe TcTyThing)
+tcLookup_maybe name
+ = tcGetEnv `thenNF_Tc` \ env ->
+ returnNF_Tc (lookup_local env name)
+
+tcLookup :: Name -> NF_TcM TcTyThing
+tcLookup name
+ = tcLookup_maybe name `thenNF_Tc` \ maybe_thing ->
+ case maybe_thing of
+ Just thing -> returnNF_Tc thing
+ other -> notFound "tcLookup" name
+ -- Extract the IdInfo from an IfaceSig imported from an interface file
+\end{code}
+
-Extending and consulting the value environment
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
\begin{code}
-tcExtendGlobalValEnv ids scope
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
+tcExtendKindEnv :: [(Name,TcKind)] -> TcM r -> TcM r
+tcExtendKindEnv pairs thing_inside
+ = tcGetEnv `thenNF_Tc` \ env ->
+ let
+ le' = extendNameEnvList (tcLEnv env) [(n, AThing k) | (n,k) <- pairs]
+ -- No need to extend global tyvars for kind checking
+ in
+ tcSetEnv (env {tcLEnv = le'}) thing_inside
+
+tcExtendTyVarEnv :: [TyVar] -> TcM r -> TcM r
+tcExtendTyVarEnv tyvars thing_inside
+ = tcGetEnv `thenNF_Tc` \ env@(TcEnv {tcLEnv = le, tcTyVars = gtvs}) ->
+ let
+ le' = extendNameEnvList le [ (getName tv, ATyVar tv) | tv <- tyvars]
+ new_tv_set = mkVarSet tyvars
+ in
+ -- 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 `thenNF_Tc` \ gtvs' ->
+ tcSetEnv (env {tcLEnv = le', tcTyVars = gtvs'}) thing_inside
+
+-- This variant, tcExtendTyVarEnvForMeths, takes *two* bunches of tyvars:
+-- the signature tyvars contain the original names
+-- the instance tyvars are what those names should be mapped to
+-- It's needed when typechecking the method bindings of class and instance decls
+-- It does *not* extend the global tyvars; tcMethodBind does that for itself
+
+tcExtendTyVarEnvForMeths :: [TyVar] -> [TcTyVar] -> TcM r -> TcM r
+tcExtendTyVarEnvForMeths sig_tyvars inst_tyvars thing_inside
+ = tcGetEnv `thenNF_Tc` \ env ->
let
- gve' = addListToUFM_Directly gve [(uniqueOf id, id) | id <- ids]
+ le' = extendNameEnvList (tcLEnv env) stuff
+ stuff = [ (getName sig_tv, ATyVar inst_tv)
+ | (sig_tv, inst_tv) <- zipEqual "tcMeth" sig_tyvars inst_tyvars
+ ]
in
- tcSetEnv (TcEnv tve tce ce gve' lve gtvs) scope
+ tcSetEnv (env {tcLEnv = le'}) thing_inside
+\end{code}
+
-tcExtendLocalValEnv names ids scope
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- tcReadMutVar gtvs `thenNF_Tc` \ global_tvs ->
+\begin{code}
+tcExtendLocalValEnv :: [(Name,TcId)] -> TcM a -> TcM a
+tcExtendLocalValEnv names_w_ids thing_inside
+ = tcGetEnv `thenNF_Tc` \ env ->
let
- lve' = addListToUFM lve (zipEqual "tcExtendLocalValEnv" names ids)
- extra_global_tyvars = tyVarsOfTypes (map idType ids)
- new_global_tyvars = global_tvs `unionTyVarSets` extra_global_tyvars
+ extra_global_tyvars = tyVarsOfTypes [idType id | (name,id) <- names_w_ids]
+ extra_env = [(name, ATcId id) | (name,id) <- names_w_ids]
+ le' = extendNameEnvList (tcLEnv env) extra_env
in
- tcNewMutVar new_global_tyvars `thenNF_Tc` \ gtvs' ->
+ tc_extend_gtvs (tcTyVars env) extra_global_tyvars `thenNF_Tc` \ gtvs' ->
+ tcSetEnv (env {tcLEnv = le', tcTyVars = gtvs'}) thing_inside
+\end{code}
+
+
+%************************************************************************
+%* *
+\subsection{The global tyvars}
+%* *
+%************************************************************************
- tcSetEnv (TcEnv tve tce ce gve lve' gtvs') scope
+\begin{code}
+tcExtendGlobalTyVars extra_global_tvs thing_inside
+ = tcGetEnv `thenNF_Tc` \ env ->
+ tc_extend_gtvs (tcTyVars env) extra_global_tvs `thenNF_Tc` \ gtvs' ->
+ tcSetEnv (env {tcTyVars = gtvs'}) thing_inside
+
+tc_extend_gtvs gtvs extra_global_tvs
+ = tcReadMutVar gtvs `thenNF_Tc` \ global_tvs ->
+ tcNewMutVar (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 :: NF_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` extra_global_tvs
- in
- tcNewMutVar new_global_tyvars `thenNF_Tc` \ gtvs' ->
- tcSetEnv (TcEnv tve tce ce gve lve gtvs') scope
+ = tcGetEnv `thenNF_Tc` \ (TcEnv {tcTyVars = gtv_var}) ->
+ tcReadMutVar gtv_var `thenNF_Tc` \ gbl_tvs ->
+ zonkTcTyVarsAndFV (varSetElems gbl_tvs) `thenNF_Tc` \ gbl_tvs' ->
+ tcWriteMutVar gtv_var gbl_tvs' `thenNF_Tc_`
+ returnNF_Tc gbl_tvs'
\end{code}
-\begin{code}
-tcLookupLocalValue :: RnName -> 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)
+%************************************************************************
+%* *
+\subsection{The instance environment}
+%* *
+%************************************************************************
-tcLookupLocalValueOK :: String -> RnName -> 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)
+\begin{code}
+tcGetInstEnv :: NF_TcM InstEnv
+tcGetInstEnv = tcGetEnv `thenNF_Tc` \ env ->
+ returnNF_Tc (tcInsts env)
+tcSetInstEnv :: InstEnv -> TcM a -> TcM a
+tcSetInstEnv ie thing_inside
+ = tcGetEnv `thenNF_Tc` \ env ->
+ tcSetEnv (env {tcInsts = ie}) thing_inside
+\end{code}
-tcLookupGlobalValue :: RnName -> NF_TcM s Id
-tcLookupGlobalValue (WiredInId id) -- wired in ids
- = returnNF_Tc id
+%************************************************************************
+%* *
+\subsection{The InstInfo type}
+%* *
+%************************************************************************
-tcLookupGlobalValue name
- = tcGetEnv `thenNF_Tc` \ (TcEnv tve tce ce gve lve gtvs) ->
- returnNF_Tc (lookupWithDefaultUFM gve def name)
- where
-#ifdef DEBUG
- def = pprPanic "tcLookupGlobalValue:" (ppr PprDebug name)
-#else
- def = panic "tcLookupGlobalValue"
-#endif
-
-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)
- where
-#ifdef DEBUG
- def = pprPanic "tcLookupGlobalValueByKey:" (pprUnique10 uniq)
-#else
- def = panic "tcLookupGlobalValueByKey"
-#endif
+The InstInfo type summarises the information in an instance declaration
+
+ instance c => k (t tvs) where b
+\begin{code}
+data InstInfo
+ = InstInfo {
+ iDFunId :: DFunId, -- The dfun id
+ iBinds :: RenamedMonoBinds, -- Bindings, b
+ iPrags :: [RenamedSig] -- User pragmas recorded for generating specialised instances
+ }
+
+pprInstInfo info = vcat [ptext SLIT("InstInfo:") <+> ppr (idType (iDFunId info)),
+ nest 4 (ppr (iBinds info))]
+
+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}
-Constructing new Ids
-~~~~~~~~~~~~~~~~~~~~
+%************************************************************************
+%* *
+\subsection{Errors}
+%* *
+%************************************************************************
\begin{code}
-newMonoIds :: [RnName] -> Kind -> ([TcIdBndr s] -> TcM s a) -> TcM s a
-
-newMonoIds names kind m
- = newTyVarTys no_of_names kind `thenNF_Tc` \ tys ->
- tcGetUniques no_of_names `thenNF_Tc` \ uniqs ->
- let
- new_ids = zipWith3Equal "newMonoIds" mk_id names uniqs tys
+badCon con_id = quotes (ppr con_id) <+> ptext SLIT("is not a data constructor")
- mk_id name uniq ty
- = let
- name_str = case (getOccName name) of { Unqual n -> n; Qual m n -> n }
- in
- mkUserLocal name_str uniq ty (getSrcLoc name)
- in
- tcExtendLocalValEnv names new_ids (m new_ids)
- where
- no_of_names = length names
-
-newLocalId :: FAST_STRING -> TcType s -> NF_TcM s (TcIdOcc s)
-newLocalId name ty
- = tcGetSrcLoc `thenNF_Tc` \ loc ->
- tcGetUnique `thenNF_Tc` \ uniq ->
- returnNF_Tc (TcId (mkUserLocal name uniq ty loc))
-
-newLocalIds :: [FAST_STRING] -> [TcType s] -> NF_TcM s [TcIdOcc 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 = TcId (mkUserLocal name uniq ty loc)
- in
- returnNF_Tc new_ids
+notFound wheRe name = failWithTc (text wheRe <> colon <+> quotes (ppr name) <+>
+ ptext SLIT("is not in scope"))
\end{code}
-
-