#include "HsVersions.h"
-import HsSyn ( HsBinds(..), MonoBinds(..), collectLocatedMonoBinders )
+import HsSyn ( HsBinds(..), MonoBinds(..), TyClDecl(..),
+ collectLocatedMonoBinders )
import RdrHsSyn ( RdrNameMonoBinds )
-import RnHsSyn ( RenamedHsBinds, RenamedMonoBinds )
+import RnHsSyn ( RenamedHsBinds, RenamedMonoBinds, RenamedTyClDecl )
import CmdLineOpts ( DynFlag(..), DynFlags )
import TcMonad
-import TcEnv ( TcEnv, tcSetInstEnv, newDFunName, InstInfo(..), pprInstInfo )
+import TcEnv ( tcSetInstEnv, newDFunName, InstInfo(..), pprInstInfo,
+ tcLookupClass, tcLookupTyCon
+ )
import TcGenDeriv -- Deriv stuff
import InstEnv ( InstEnv, simpleDFunClassTyCon, extendInstEnv )
import TcSimplify ( tcSimplifyThetas )
import RnBinds ( rnMethodBinds, rnTopMonoBinds )
import RnEnv ( bindLocatedLocalsRn )
-import RnMonad ( --RnNameSupply,
- renameSourceCode, thenRn, mapRn, returnRn )
+import RnMonad ( renameDerivedCode, thenRn, mapRn, returnRn )
import HscTypes ( DFunId, PersistentRenamerState )
import BasicTypes ( Fixity )
import Class ( classKey, Class )
import ErrUtils ( dumpIfSet_dyn, Message )
import MkId ( mkDictFunId )
-import Id ( idType )
import DataCon ( dataConArgTys, isNullaryDataCon, isExistentialDataCon )
import PrelInfo ( needsDataDeclCtxtClassKeys )
import Maybes ( maybeToBool, catMaybes )
import Module ( Module )
-import Name ( Name, isLocallyDefined, getSrcLoc )
+import Name ( Name, getSrcLoc )
import RdrName ( RdrName )
-import TyCon ( tyConTyVars, tyConDataCons, tyConDerivings,
+import TyCon ( tyConTyVars, tyConDataCons,
tyConTheta, maybeTyConSingleCon, isDataTyCon,
isEnumerationTyCon, TyCon
)
-import Type ( TauType, PredType(..), mkTyVarTys, mkTyConApp,
- splitDFunTy, isUnboxedType
- )
+import Type ( TauType, ThetaType, PredType, mkTyVarTys, mkTyConApp,
+ isUnLiftedType, mkClassPred )
import Var ( TyVar )
import PrelNames
-import Util ( zipWithEqual, sortLt, thenCmp )
+import Util ( zipWithEqual, sortLt )
import ListSetOps ( removeDups, assoc )
import Outputable
+import List ( nub )
\end{code}
%************************************************************************
-- The Name is the name for the DFun we'll build
-- The tyvars bind all the variables in the RHS
-type DerivRhs = [(Class, [TauType])] -- Same as a ThetaType!
- --[PredType] -- ... | Class Class [Type==TauType]
-
+type DerivRhs = ThetaType
type DerivSoln = DerivRhs
\end{code}
-> Module -- name of module under scrutiny
-> InstEnv -- What we already know about instances
-> (Name -> Maybe Fixity) -- used in deriving Show and Read
- -> [TyCon] -- "local_tycons" ???
+ -> [RenamedTyClDecl] -- All type constructors
-> TcM ([InstInfo], -- The generated "instance decls".
RenamedHsBinds) -- Extra generated bindings
-tcDeriving prs mod inst_env_in get_fixity local_tycons
+tcDeriving prs mod inst_env_in get_fixity tycl_decls
= recoverTc (returnTc ([], EmptyBinds)) $
-- Fish the "deriving"-related information out of the TcEnv
-- and make the necessary "equations".
- makeDerivEqns mod local_tycons `thenTc` \ eqns ->
+ makeDerivEqns tycl_decls `thenTc` \ eqns ->
if null eqns then
returnTc ([], EmptyBinds)
else
-- The only tricky bit is that the extra_binds must scope over the
-- method bindings for the instances.
(rn_method_binds_s, rn_extra_binds)
- = renameSourceCode dflags mod prs (
+ = renameDerivedCode dflags mod prs (
bindLocatedLocalsRn (ptext (SLIT("deriving"))) mbinders $ \ _ ->
rnTopMonoBinds extra_mbinds [] `thenRn` \ (rn_extra_binds, _) ->
mapRn rn_meths method_binds_s `thenRn` \ rn_method_binds_s ->
returnRn (rn_method_binds_s, rn_extra_binds)
)
- new_inst_infos = map gen_inst_info (new_dfuns `zip` rn_method_binds_s)
+ new_inst_infos = zipWith gen_inst_info new_dfuns rn_method_binds_s
in
ioToTc (dumpIfSet_dyn dflags Opt_D_dump_deriv "Derived instances"
where
-- Make a Real dfun instead of the dummy one we have so far
- gen_inst_info :: (DFunId, RenamedMonoBinds) -> InstInfo
- gen_inst_info (dfun, binds)
- = InstInfo { iLocal = True,
- iClass = clas, iTyVars = tyvars,
- iTys = tys, iTheta = theta,
- iDFunId = dfun,
- iBinds = binds,
- iLoc = getSrcLoc dfun, iPrags = [] }
- where
- (tyvars, theta, clas, tys) = splitDFunTy (idType dfun)
+ gen_inst_info :: DFunId -> RenamedMonoBinds -> InstInfo
+ gen_inst_info dfun binds
+ = InstInfo { iDFunId = dfun,
+ iBinds = binds, iPrags = [] }
rn_meths meths = rnMethodBinds [] meths `thenRn` \ (meths', _) -> returnRn meths'
-- Ignore the free vars returned
all those.
\begin{code}
-makeDerivEqns :: Module -> [TyCon] -> TcM [DerivEqn]
+makeDerivEqns :: [RenamedTyClDecl] -> TcM [DerivEqn]
-makeDerivEqns this_mod local_tycons
- = let
- think_about_deriving = need_deriving local_tycons
- (derive_these, _) = removeDups cmp_deriv think_about_deriving
- in
- if null local_tycons then
- returnTc [] -- Bale out now
- else
- mapTc mk_eqn derive_these `thenTc` \ maybe_eqns ->
+makeDerivEqns tycl_decls
+ = mapTc mk_eqn derive_these `thenTc` \ maybe_eqns ->
returnTc (catMaybes maybe_eqns)
where
------------------------------------------------------------------
- need_deriving :: [TyCon] -> [(Class, TyCon)]
- -- find the tycons that have `deriving' clauses;
-
- need_deriving tycons_to_consider
- = foldr (\ tycon acc -> [(clas,tycon) | clas <- tyConDerivings tycon] ++ acc)
- []
- tycons_to_consider
-
- ------------------------------------------------------------------
- cmp_deriv :: (Class, TyCon) -> (Class, TyCon) -> Ordering
- cmp_deriv (c1, t1) (c2, t2)
- = (c1 `compare` c2) `thenCmp` (t1 `compare` t2)
+ derive_these :: [(Name, Name)]
+ -- Find the (Class,TyCon) pairs that must be `derived'
+ -- NB: only source-language decls have deriving, no imported ones do
+ derive_these = [ (clas,tycon)
+ | TyData {tcdName = tycon, tcdDerivs = Just classes} <- tycl_decls,
+ clas <- nub classes ]
------------------------------------------------------------------
- mk_eqn :: (Class, TyCon) -> NF_TcM (Maybe DerivEqn)
+ mk_eqn :: (Name, Name) -> NF_TcM (Maybe DerivEqn)
-- we swizzle the tyvars and datacons out of the tycon
-- to make the rest of the equation
- mk_eqn (clas, tycon)
- = case chk_out clas tycon of
+ mk_eqn (clas_name, tycon_name)
+ = tcLookupClass clas_name `thenNF_Tc` \ clas ->
+ tcLookupTyCon tycon_name `thenNF_Tc` \ tycon ->
+ let
+ clas_key = classKey clas
+ tyvars = tyConTyVars tycon
+ tyvar_tys = mkTyVarTys tyvars
+ ty = mkTyConApp tycon tyvar_tys
+ data_cons = tyConDataCons tycon
+ locn = getSrcLoc tycon
+ constraints = extra_constraints ++ concat (map mk_constraints data_cons)
+
+ -- "extra_constraints": see notes above about contexts on data decls
+ extra_constraints
+ | offensive_class = tyConTheta tycon
+ | otherwise = []
+
+ offensive_class = clas_key `elem` needsDataDeclCtxtClassKeys
+
+ mk_constraints data_con
+ = [ mkClassPred clas [arg_ty]
+ | arg_ty <- dataConArgTys data_con tyvar_tys,
+ not (isUnLiftedType arg_ty) -- No constraints for unlifted types?
+ ]
+ in
+ case chk_out clas tycon of
Just err -> addErrTc err `thenNF_Tc_`
returnNF_Tc Nothing
- Nothing -> newDFunName this_mod clas tyvar_tys locn `thenNF_Tc` \ dfun_name ->
+ Nothing -> newDFunName clas [ty] locn `thenNF_Tc` \ dfun_name ->
returnNF_Tc (Just (dfun_name, clas, tycon, tyvars, constraints))
- where
- clas_key = classKey clas
- tyvars = tyConTyVars tycon -- ToDo: Do we need new tyvars ???
- tyvar_tys = mkTyVarTys tyvars
- data_cons = tyConDataCons tycon
- locn = getSrcLoc tycon
-
- constraints = extra_constraints ++ concat (map mk_constraints data_cons)
-
- -- "extra_constraints": see notes above about contexts on data decls
- extra_constraints
- | offensive_class = tyConTheta tycon
- | otherwise = []
- where
- offensive_class = clas_key `elem` needsDataDeclCtxtClassKeys
- mk_constraints data_con
- = [ (clas, [arg_ty])
- | arg_ty <- instd_arg_tys,
- not (isUnboxedType arg_ty) -- No constraints for unboxed types?
- ]
- where
- instd_arg_tys = dataConArgTys data_con tyvar_tys
+
------------------------------------------------------------------
chk_out :: Class -> TyCon -> Maybe Message
in
-- Simplify each RHS
tcSetInstEnv inst_env (
- listTc [ tcAddErrCtxt (derivCtxt tc) $
+ listTc [ tcAddSrcLoc (getSrcLoc tc) $
+ tcAddErrCtxt (derivCtxt tc) $
tcSimplifyThetas deriv_rhs
| (_, _,tc,_,deriv_rhs) <- orig_eqns ]
) `thenTc` \ next_solns ->
-- They'll appear later, when we do the top-level extendInstEnvs
mk_deriv_dfun (dfun_name, clas, tycon, tyvars, _) theta
- = mkDictFunId dfun_name clas tyvars [mkTyConApp tycon (mkTyVarTys tyvars)]
- (map pair2PredType theta)
-
- pair2PredType (clas, tautypes) = Class clas tautypes
+ = mkDictFunId dfun_name clas tyvars
+ [mkTyConApp tycon (mkTyVarTys tyvars)]
+ theta
\end{code}
%************************************************************************
-- names.)
gen_bind :: (Name -> Maybe Fixity) -> DFunId -> RdrNameMonoBinds
gen_bind get_fixity dfun
- | not (isLocallyDefined tycon) = EmptyMonoBinds
| clas `hasKey` showClassKey = gen_Show_binds get_fixity tycon
| clas `hasKey` readClassKey = gen_Read_binds get_fixity tycon
| otherwise
con2tag_Foo :: Foo ... -> Int#
tag2con_Foo :: Int -> Foo ... -- easier if Int, not Int#
-maxtag_Foo :: Int -- ditto (NB: not unboxed)
+maxtag_Foo :: Int -- ditto (NB: not unlifted)
We have a @con2tag@ function for a tycon if: