#include "HsVersions.h"
import CmdLineOpts ( DynFlags, DynFlag(..), dopt )
-import HsSyn ( HsDecl(..), TyClDecl(..),
- HsTyVarBndr,
- ConDecl(..),
- Sig(..), HsPred(..),
- tyClDeclName, hsTyVarNames,
+import HsSyn ( TyClDecl(..),
+ ConDecl(..), Sig(..), HsPred(..),
+ tyClDeclName, hsTyVarNames, tyClDeclTyVars,
isIfaceSigDecl, isClassDecl, isSynDecl, isClassOpSig
)
-import RnHsSyn ( RenamedHsDecl, RenamedTyClDecl, tyClDeclFVs )
-import BasicTypes ( RecFlag(..), NewOrData(..), isRec )
+import RnHsSyn ( RenamedTyClDecl, tyClDeclFVs )
+import BasicTypes ( RecFlag(..), NewOrData(..) )
+import HscTypes ( implicitTyThingIds )
+import Module ( Module )
import TcMonad
import TcEnv ( TcEnv, RecTcEnv, TcTyThing(..), TyThing(..), TyThingDetails(..),
- tcExtendKindEnv, tcLookup, tcExtendGlobalEnv )
-import TcTyDecls ( tcTyDecl1, kcConDetails, mkNewTyConRep )
-import TcClassDcl ( tcClassDecl1 )
-import TcMonoType ( kcHsTyVars, kcHsType, kcHsBoxedSigType, kcHsContext, mkTyClTyVars )
-import TcType ( TcKind, newKindVar, zonkKindEnv )
-
-import TcUnify ( unifyKind )
+ tcExtendKindEnv, tcLookup, tcExtendGlobalEnv, tcExtendGlobalValEnv,
+ isLocalThing )
+import TcTyDecls ( tcTyDecl, kcConDetails, checkValidTyCon )
+import TcClassDcl ( tcClassDecl1, checkValidClass )
import TcInstDcls ( tcAddDeclCtxt )
-import Type ( Kind, mkArrowKind, boxedTypeKind, zipFunTys )
+import TcMonoType ( kcHsTyVars, kcHsType, kcHsLiftedSigType, kcHsContext, mkTyClTyVars )
+import TcMType ( newKindVar, zonkKindEnv )
+import TcUnify ( unifyKind )
+import TcType ( Type, Kind, TcKind, mkArrowKind, liftedTypeKind, zipFunTys )
+import Type ( splitTyConApp_maybe )
import Variance ( calcTyConArgVrcs )
import Class ( Class, mkClass, classTyCon )
-import TyCon ( TyCon, tyConKind, ArgVrcs, AlgTyConFlavour(..),
- mkSynTyCon, mkAlgTyCon, mkClassTyCon )
-import DataCon ( isNullaryDataCon )
+import TyCon ( TyCon, ArgVrcs, AlgTyConFlavour(..),
+ tyConKind, tyConTyVars, tyConDataCons, isNewTyCon,
+ mkSynTyCon, mkAlgTyCon, mkClassTyCon, mkForeignTyCon,
+ )
+import TysWiredIn ( unitTy )
+import Subst ( substTyWith )
+import DataCon ( dataConOrigArgTys )
import Var ( varName )
import FiniteMap
import Digraph ( stronglyConnComp, SCC(..) )
-import Name ( Name, NamedThing(..), getSrcLoc, isTyVarName )
-import Name ( NameEnv, mkNameEnv, lookupNameEnv_NF )
+import Name ( Name, getSrcLoc, isTyVarName )
+import NameEnv
import NameSet
import Outputable
import Maybes ( mapMaybe )
~~~~~~~~~~~~~~~~~
\begin{code}
tcTyAndClassDecls :: RecTcEnv -- Knot tying stuff
- -> [RenamedHsDecl]
+ -> Module -- Current module
+ -> [RenamedTyClDecl]
-> TcM TcEnv
-tcTyAndClassDecls unf_env decls
+tcTyAndClassDecls unf_env this_mod decls
= sortByDependency decls `thenTc` \ groups ->
- tcGroups unf_env groups
+ tcGroups unf_env this_mod groups
-tcGroups unf_env []
+tcGroups unf_env this_mod []
= tcGetEnv `thenNF_Tc` \ env ->
returnTc env
-tcGroups unf_env (group:groups)
- = tcGroup unf_env group `thenTc` \ env ->
- tcSetEnv env $
- tcGroups unf_env groups
+tcGroups unf_env this_mod (group:groups)
+ = tcGroup unf_env this_mod group `thenTc` \ env ->
+ tcSetEnv env $
+ tcGroups unf_env this_mod groups
\end{code}
Dealing with a group
to tcTyClDecl1.
-Step 6: tcTyClDecl1 again
+Step 6: Extend environment
+ We extend the type environment with bindings not only for the TyCons and Classes,
+ but also for their "implicit Ids" like data constructors and class selectors
+
+Step 7: checkValidTyCl
For a recursive group only, check all the decls again, just
- but this time with the wimp flag off. Now we can check things
- like whether a function argument is an unboxed tuple, looking
- through type synonyms properly. We can't do that in Step 5.
+ to check all the side conditions on validity. We could not
+ do this before because we were in a mutually recursive knot.
+
The knot-tying parameters: @rec_details_list@ is an alist mapping @Name@s to
@TyThing@s. @rec_vrcs@ is a finite map from @Name@s to @ArgVrcs@s.
\begin{code}
-tcGroup :: RecTcEnv -> SCC RenamedTyClDecl -> TcM TcEnv
-tcGroup unf_env scc
- = getDOptsTc `thenTc` \ dflags ->
+tcGroup :: RecTcEnv -> Module -> SCC RenamedTyClDecl -> TcM TcEnv
+tcGroup unf_env this_mod scc
+ = getDOptsTc `thenNF_Tc` \ dflags ->
-- Step 1
mapNF_Tc getInitialKind decls `thenNF_Tc` \ initial_kinds ->
zonkKindEnv initial_kinds `thenNF_Tc` \ final_kinds ->
-- Tie the knot
- fixTc ( \ ~(rec_details_list, _) ->
+ traceTc (text "starting" <+> ppr final_kinds) `thenTc_`
+ fixTc ( \ ~(rec_details_list, _, _) ->
-- Step 4
let
kind_env = mkNameEnv final_kinds
rec_details = mkNameEnv rec_details_list
- tyclss, all_tyclss :: [(Name, TyThing)]
+ tyclss, all_tyclss :: [TyThing]
tyclss = map (buildTyConOrClass dflags is_rec kind_env
rec_vrcs rec_details) decls
-- Add the tycons that come from the classes
-- We want them in the environment because
-- they are mentioned in interface files
- all_tyclss = [ (getName tycon, ATyCon tycon) | (_, AClass clas) <- tyclss,
- let tycon = classTyCon clas
- ] ++ tyclss
+ all_tyclss = [ ATyCon (classTyCon clas) | AClass clas <- tyclss]
+ ++ tyclss
-- Calculate variances, and (yes!) feed back into buildTyConOrClass.
- rec_vrcs = calcTyConArgVrcs [tc | (_, ATyCon tc) <- all_tyclss]
+ rec_vrcs = calcTyConArgVrcs [tc | ATyCon tc <- all_tyclss]
in
-- Step 5
- tcExtendGlobalEnv all_tyclss $
- mapTc (tcTyClDecl1 is_rec unf_env) decls `thenTc` \ tycls_details ->
+ -- Extend the environment with the final
+ -- TyCons/Classes and check the decls
+ tcExtendGlobalEnv all_tyclss $
+ mapTc (tcTyClDecl1 unf_env) decls `thenTc` \ tycls_details ->
+
+ -- Step 6
+ -- Extend the environment with implicit Ids
+ tcExtendGlobalValEnv (implicitTyThingIds all_tyclss) $
-- Return results
- tcGetEnv `thenNF_Tc` \ env ->
- returnTc (tycls_details, env)
- ) `thenTc` \ (_, env) ->
-
- -- Step 6
- -- For a recursive group, check all the types again,
- -- this time with the wimp flag off
- (if isRec is_rec then
- tcSetEnv env (mapTc_ (tcTyClDecl1 NonRecursive unf_env) decls)
- else
- returnTc ()
- ) `thenTc_`
+ tcGetEnv `thenNF_Tc` \ env ->
+ returnTc (tycls_details, tyclss, env)
+ ) `thenTc` \ (_, tyclss, env) ->
+
+ -- Step 7: Check validity
+ traceTc (text "ready for validity check") `thenTc_`
+ tcSetEnv env (
+ mapTc_ (checkValidTyCl this_mod) decls
+ ) `thenTc_`
+ traceTc (text "done") `thenTc_`
+
returnTc env
+
where
is_rec = case scc of
AcyclicSCC _ -> NonRecursive
AcyclicSCC decl -> [decl]
CyclicSCC decls -> decls
-tcTyClDecl1 is_rec unf_env decl
- | isClassDecl decl = tcAddDeclCtxt decl (tcClassDecl1 is_rec unf_env decl)
- | otherwise = tcAddDeclCtxt decl (tcTyDecl1 is_rec decl)
+tcTyClDecl1 unf_env decl
+ | isClassDecl decl = tcAddDeclCtxt decl (tcClassDecl1 unf_env decl)
+ | otherwise = tcAddDeclCtxt decl (tcTyDecl unf_env decl)
+
+checkValidTyCl this_mod decl
+ = tcLookup (tcdName decl) `thenNF_Tc` \ (AGlobal thing) ->
+ if not (isLocalThing this_mod thing) then
+ -- Don't bother to check validity for non-local things
+ returnTc ()
+ else
+ tcAddDeclCtxt decl $
+ case thing of
+ ATyCon tc -> checkValidTyCon tc
+ AClass cl -> checkValidClass cl
\end{code}
\begin{code}
getInitialKind :: RenamedTyClDecl -> NF_TcM (Name, TcKind)
-getInitialKind (TySynonym name tyvars _ _)
- = kcHsTyVars tyvars `thenNF_Tc` \ arg_kinds ->
- newKindVar `thenNF_Tc` \ result_kind ->
- returnNF_Tc (name, mk_kind arg_kinds result_kind)
-
-getInitialKind (TyData _ _ name tyvars _ _ _ _ _ _)
- = kcHsTyVars tyvars `thenNF_Tc` \ arg_kinds ->
- returnNF_Tc (name, mk_kind arg_kinds boxedTypeKind)
-
-getInitialKind (ClassDecl _ name tyvars _ _ _ _ _ )
- = kcHsTyVars tyvars `thenNF_Tc` \ arg_kinds ->
- returnNF_Tc (name, mk_kind arg_kinds boxedTypeKind)
+getInitialKind decl
+ = kcHsTyVars (tyClDeclTyVars decl) `thenNF_Tc` \ arg_kinds ->
+ newKindVar `thenNF_Tc` \ result_kind ->
+ returnNF_Tc (tcdName decl, mk_kind arg_kinds result_kind)
mk_kind tvs_w_kinds res_kind = foldr (mkArrowKind . snd) res_kind tvs_w_kinds
\end{code}
\begin{code}
kcTyClDecl :: RenamedTyClDecl -> TcM ()
-kcTyClDecl decl@(TySynonym tycon_name hs_tyvars rhs loc)
- = tcAddDeclCtxt decl $
- kcTyClDeclBody tycon_name hs_tyvars $ \ result_kind ->
- kcHsType rhs `thenTc` \ rhs_kind ->
+kcTyClDecl decl@(TySynonym {tcdSynRhs = rhs})
+ = kcTyClDeclBody decl $ \ result_kind ->
+ kcHsType rhs `thenTc` \ rhs_kind ->
unifyKind result_kind rhs_kind
-kcTyClDecl decl@(TyData new_or_data context tycon_name hs_tyvars con_decls _ _ loc _ _)
- = tcAddDeclCtxt decl $
- kcTyClDeclBody tycon_name hs_tyvars $ \ result_kind ->
+kcTyClDecl (ForeignType {}) = returnTc ()
+
+kcTyClDecl decl@(TyData {tcdND = new_or_data, tcdCtxt = context, tcdCons = con_decls})
+ = kcTyClDeclBody decl $ \ result_kind ->
kcHsContext context `thenTc_`
mapTc_ kc_con_decl con_decls
where
kc_con_decl (ConDecl _ _ ex_tvs ex_ctxt details loc)
- = tcAddSrcLoc loc $
- kcHsTyVars ex_tvs `thenNF_Tc` \ kind_env ->
+ = kcHsTyVars ex_tvs `thenNF_Tc` \ kind_env ->
tcExtendKindEnv kind_env $
kcConDetails new_or_data ex_ctxt details
-kcTyClDecl decl@(ClassDecl context class_name
- hs_tyvars fundeps class_sigs
- _ _ loc)
- = tcAddDeclCtxt decl $
- kcTyClDeclBody class_name hs_tyvars $ \ result_kind ->
- kcHsContext context `thenTc_`
+kcTyClDecl decl@(ClassDecl {tcdCtxt = context, tcdSigs = class_sigs})
+ = kcTyClDeclBody decl $ \ result_kind ->
+ kcHsContext context `thenTc_`
mapTc_ kc_sig (filter isClassOpSig class_sigs)
where
- kc_sig (ClassOpSig _ _ op_ty loc) = tcAddSrcLoc loc (kcHsBoxedSigType op_ty)
+ kc_sig (ClassOpSig _ _ op_ty loc) = kcHsLiftedSigType op_ty
-kcTyClDeclBody :: Name -> [HsTyVarBndr Name] -- Kind of the tycon/cls and its tyvars
- -> (Kind -> TcM a) -- Thing inside
- -> TcM a
+kcTyClDeclBody :: RenamedTyClDecl -> (Kind -> TcM a) -> TcM a
-- Extend the env with bindings for the tyvars, taken from
-- the kind of the tycon/class. Give it to the thing inside, and
-- check the result kind matches
-kcTyClDeclBody tc_name hs_tyvars thing_inside
- = tcLookup tc_name `thenNF_Tc` \ thing ->
+kcTyClDeclBody decl thing_inside
+ = tcAddDeclCtxt decl $
+ tcLookup (tcdName decl) `thenNF_Tc` \ thing ->
let
kind = case thing of
AGlobal (ATyCon tc) -> tyConKind tc
AThing kind -> kind
-- For some odd reason, a class doesn't include its kind
- (tyvars_w_kinds, result_kind) = zipFunTys (hsTyVarNames hs_tyvars) kind
+ (tyvars_w_kinds, result_kind) = zipFunTys (hsTyVarNames (tyClDeclTyVars decl)) kind
in
tcExtendKindEnv tyvars_w_kinds (thing_inside result_kind)
\end{code}
+
%************************************************************************
%* *
\subsection{Step 4: Building the tycon/class}
:: DynFlags
-> RecFlag -> NameEnv Kind
-> FiniteMap TyCon ArgVrcs -> NameEnv TyThingDetails
- -> RenamedTyClDecl -> (Name, TyThing)
- -- Can't fail; the only reason it's in the monad
- -- is so it can zonk the kinds
+ -> RenamedTyClDecl -> TyThing
buildTyConOrClass dflags is_rec kenv rec_vrcs rec_details
- (TySynonym tycon_name tyvar_names rhs src_loc)
- = (tycon_name, ATyCon tycon)
+ (TySynonym {tcdName = tycon_name, tcdTyVars = tyvar_names})
+ = ATyCon tycon
where
tycon = mkSynTyCon tycon_name tycon_kind arity tyvars rhs_ty argvrcs
tycon_kind = lookupNameEnv_NF kenv tycon_name
argvrcs = lookupWithDefaultFM rec_vrcs bogusVrcs tycon
buildTyConOrClass dflags is_rec kenv rec_vrcs rec_details
- (TyData data_or_new context tycon_name tyvar_names _ nconstrs _ src_loc name1 name2)
- = (tycon_name, ATyCon tycon)
+ (TyData {tcdND = data_or_new, tcdName = tycon_name, tcdTyVars = tyvar_names,
+ tcdNCons = nconstrs, tcdSysNames = sys_names})
+ = ATyCon tycon
where
tycon = mkAlgTyCon tycon_name tycon_kind tyvars ctxt argvrcs
- data_cons nconstrs
+ data_cons nconstrs sel_ids
flavour is_rec gen_info
gen_info | not (dopt Opt_Generics dflags) = Nothing
- | otherwise = mkTyConGenInfo tycon name1 name2
+ | otherwise = mkTyConGenInfo tycon sys_names
- DataTyDetails ctxt data_cons = lookupNameEnv_NF rec_details tycon_name
+ DataTyDetails ctxt data_cons sel_ids = lookupNameEnv_NF rec_details tycon_name
tycon_kind = lookupNameEnv_NF kenv tycon_name
tyvars = mkTyClTyVars tycon_kind tyvar_names
argvrcs = lookupWithDefaultFM rec_vrcs bogusVrcs tycon
+ -- Watch out! mkTyConApp asks whether the tycon is a NewType,
+ -- so flavour has to be able to answer this question without consulting rec_details
flavour = case data_or_new of
- NewType -> NewTyCon (mkNewTyConRep tycon)
- DataType | all isNullaryDataCon data_cons -> EnumTyCon
- | otherwise -> DataTyCon
+ NewType -> NewTyCon (mkNewTyConRep tycon)
+ DataType | all (null . dataConOrigArgTys) data_cons -> EnumTyCon
+ | otherwise -> DataTyCon
+ -- NB (null . dataConOrigArgTys). It used to say isNullaryDataCon
+ -- but that looks at the *representation* arity, and that in turn
+ -- depends on deciding whether to unpack the args, and that
+ -- depends on whether it's a data type or a newtype --- so
+ -- in the recursive case we can get a loop. This version is simple!
buildTyConOrClass dflags is_rec kenv rec_vrcs rec_details
- (ClassDecl context class_name
- tyvar_names fundeps class_sigs def_methods
- name_list src_loc)
- = (class_name, AClass clas)
+ (ForeignType {tcdName = tycon_name, tcdExtName = tycon_ext_name})
+ = ATyCon (mkForeignTyCon tycon_name tycon_ext_name liftedTypeKind 0 [])
+
+buildTyConOrClass dflags is_rec kenv rec_vrcs rec_details
+ (ClassDecl {tcdName = class_name, tcdTyVars = tyvar_names,
+ tcdFDs = fundeps, tcdSysNames = name_list} )
+ = AClass clas
where
(tycon_name, _, _, _) = getClassDeclSysNames name_list
clas = mkClass class_name tyvars fds
argvrcs dict_con
clas -- Yes! It's a dictionary
flavour
+ is_rec
+ -- A class can be recursive, and in the case of newtypes
+ -- this matters. For example
+ -- class C a where { op :: C b => a -> b -> Int }
+ -- Because C has only one operation, it is represented by
+ -- a newtype, and it should be a *recursive* newtype.
+ -- [If we don't make it a recursive newtype, we'll expand the
+ -- newtype like a synonym, but that will lead toan inifinite type
ClassDetails sc_theta sc_sel_ids op_items dict_con = lookupNameEnv_NF rec_details class_name
class_kind = lookupNameEnv_NF kenv class_name
tyvars = mkTyClTyVars class_kind tyvar_names
argvrcs = lookupWithDefaultFM rec_vrcs bogusVrcs tycon
- n_fields = length sc_sel_ids + length op_items
- flavour | n_fields == 1 = NewTyCon (mkNewTyConRep tycon)
- | otherwise = DataTyCon
+ flavour = case dataConOrigArgTys dict_con of
+ -- The tyvars in the datacon are the same as in the class
+ [rep_ty] -> NewTyCon rep_ty
+ other -> DataTyCon
-- We can find the functional dependencies right away,
-- and it is vital to do so. Why? Because in the next pass
bogusVrcs = panic "Bogus tycon arg variances"
\end{code}
+\begin{code}
+mkNewTyConRep :: TyCon -- The original type constructor
+ -> Type -- Chosen representation type
+ -- (guaranteed not to be another newtype)
+
+-- Find the representation type for this newtype TyCon
+--
+-- The non-recursive newtypes are easy, because they look transparent
+-- to splitTyConApp_maybe, but recursive ones really are represented as
+-- TyConApps (see TypeRep).
+--
+-- The trick is to to deal correctly with recursive newtypes
+-- such as newtype T = MkT T
+
+mkNewTyConRep tc
+ = go [] tc
+ where
+ -- Invariant: tc is a NewTyCon
+ -- tcs have been seen before
+ go tcs tc
+ | tc `elem` tcs = unitTy
+ | otherwise
+ = let
+ rep_ty = head (dataConOrigArgTys (head (tyConDataCons tc)))
+ in
+ case splitTyConApp_maybe rep_ty of
+ Nothing -> rep_ty
+ Just (tc', tys) | not (isNewTyCon tc') -> rep_ty
+ | otherwise -> go1 (tc:tcs) tc' tys
+
+ go1 tcs tc tys = substTyWith (tyConTyVars tc) tys (go tcs tc)
+\end{code}
%************************************************************************
%* *
Dependency analysis
~~~~~~~~~~~~~~~~~~~
\begin{code}
-sortByDependency :: [RenamedHsDecl] -> TcM [SCC RenamedTyClDecl]
+sortByDependency :: [RenamedTyClDecl] -> TcM [SCC RenamedTyClDecl]
sortByDependency decls
= let -- CHECK FOR CLASS CYCLES
cls_sccs = stronglyConnComp (mapMaybe mkClassEdges tycl_decls)
in
returnTc decl_sccs
where
- tycl_decls = [d | TyClD d <- decls, not (isIfaceSigDecl d)]
+ tycl_decls = filter (not . isIfaceSigDecl) decls
edges = map mkEdges tycl_decls
is_syn_decl (d, _, _) = isSynDecl d
mkClassEdges :: RenamedTyClDecl -> Maybe (RenamedTyClDecl, Name, [Name])
-mkClassEdges decl@(ClassDecl ctxt name _ _ _ _ _ _) = Just (decl, name, [c | HsPClass c _ <- ctxt])
-mkClassEdges other_decl = Nothing
+mkClassEdges decl@(ClassDecl {tcdCtxt = ctxt, tcdName = name}) = Just (decl, name, [c | HsClassP c _ <- ctxt])
+mkClassEdges other_decl = Nothing
mkEdges :: RenamedTyClDecl -> (RenamedTyClDecl, Name, [Name])
mkEdges decl = (decl, tyClDeclName decl, tyClDeclFTVs decl)
projects / ghc-hetmet.git / blobdiff