#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 ( TcEnv, tcSetInstEnv, newDFunName, InstInfo(..), pprInstInfo,
+ tcLookupClass, tcLookupTyCon
+ )
import TcGenDeriv -- Deriv stuff
import InstEnv ( InstEnv, simpleDFunClassTyCon, extendInstEnv )
import TcSimplify ( tcSimplifyThetas )
import PrelInfo ( needsDataDeclCtxtClassKeys )
import Maybes ( maybeToBool, catMaybes )
import Module ( Module )
-import Name ( Name, isFrom, 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, isUnboxedType )
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}
%************************************************************************
-> Module -- name of module under scrutiny
-> InstEnv -- What we already know about instances
-> (Name -> Maybe Fixity) -- used in deriving Show and Read
- -> [TyCon] -- All type constructors
+ -> [RenamedTyClDecl] -- All type constructors
-> TcM ([InstInfo], -- The generated "instance decls".
RenamedHsBinds) -- Extra generated bindings
-tcDeriving prs mod inst_env_in get_fixity 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 tycons `thenTc` \ eqns ->
+ makeDerivEqns mod tycl_decls `thenTc` \ eqns ->
if null eqns then
returnTc ([], EmptyBinds)
else
all those.
\begin{code}
-makeDerivEqns :: Module -> [TyCon] -> TcM [DerivEqn]
+makeDerivEqns :: Module -> [RenamedTyClDecl] -> TcM [DerivEqn]
-makeDerivEqns this_mod tycons
- = let
- think_about_deriving = need_deriving tycons
- (derive_these, _) = removeDups cmp_deriv think_about_deriving
- in
- if null think_about_deriving then
- returnTc [] -- Bale out now
- else
- mapTc mk_eqn derive_these `thenTc` \ maybe_eqns ->
+makeDerivEqns this_mod 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
- = [ (clas,tycon) | tycon <- tycons_to_consider,
- isFrom this_mod tycon,
- clas <- tyConDerivings tycon ]
+ 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 _ _ tycon _ _ _ (Just classes) _ _ _ <- tycl_decls,
+ clas <- nub classes ]
------------------------------------------------------------------
- cmp_deriv :: (Class, TyCon) -> (Class, TyCon) -> Ordering
- cmp_deriv (c1, t1) (c2, t2)
- = (c1 `compare` c2) `thenCmp` (t1 `compare` t2)
-
- ------------------------------------------------------------------
- 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
+ = [ (clas, [arg_ty])
+ | arg_ty <- dataConArgTys data_con tyvar_tys,
+ not (isUnboxedType arg_ty) -- No constraints for unboxed types?
+ ]
+ in
+ case chk_out clas tycon of
Just err -> addErrTc err `thenNF_Tc_`
returnNF_Tc Nothing
Nothing -> newDFunName this_mod clas [ty] locn `thenNF_Tc` \ dfun_name ->
returnNF_Tc (Just (dfun_name, clas, tycon, tyvars, constraints))
- where
- 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 = []
- 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
projects / ghc-hetmet.git / blobdiff