\begin{code}
module TcMatches ( tcMatchesFun, tcGRHSsPat, tcMatchesCase, tcMatchLambda,
TcMatchCtxt(..),
- tcStmts, tcDoStmts, tcBody,
+ tcStmts, tcStmtsAndThen, tcDoStmts, tcBody,
tcDoStmt, tcMDoStmt, tcGuardStmt
) where
tcGRHS :: TcMatchCtxt -> TcRhoType -> GRHS Name -> TcM (GRHS TcId)
tcGRHS ctxt res_ty (GRHS guards rhs)
- = do { (guards', rhs') <- tcStmts stmt_ctxt tcGuardStmt guards res_ty $
+ = do { (guards', rhs') <- tcStmtsAndThen stmt_ctxt tcGuardStmt guards res_ty $
mc_body ctxt rhs
; return (GRHS guards' rhs') }
where
-> TcM (HsExpr TcId) -- Returns a HsDo
tcDoStmts ListComp stmts res_ty
= do { (coi, elt_ty) <- matchExpectedListTy res_ty
- ; stmts' <- tcStmts ListComp (tcLcStmt listTyCon) stmts res_ty
+ ; stmts' <- tcStmts ListComp (tcLcStmt listTyCon) stmts elt_ty
; return $ mkHsWrapCoI coi
(HsDo ListComp stmts' (mkListTy elt_ty)) }
= do { stmts' <- tcStmts MonadComp tcMcStmt stmts res_ty
; return (HsDo MonadComp stmts' res_ty) }
-tcDoStmts ctxt _ _ _ _ = pprPanic "tcDoStmts" (pprStmtContext ctxt)
+tcDoStmts ctxt _ _ = pprPanic "tcDoStmts" (pprStmtContext ctxt)
tcBody :: LHsExpr Name -> TcRhoType -> TcM (LHsExpr TcId)
tcBody body res_ty
-> TcRhoType
-> TcM [LStmt TcId]
tcStmts ctxt stmt_chk stmts res_ty
- = do { (stmts', _) <- tcStmtsAndThen ctxt stmt_check stmts res_ty $
+ = do { (stmts', _) <- tcStmtsAndThen ctxt stmt_chk stmts res_ty $
const (return ())
; return stmts' }
tcLcStmt :: TyCon -- The list/Parray type constructor ([] or PArray)
-> TcStmtChecker
-tcLcStmt m_tc ctxt (LastStmt body _) elt_ty thing_inside
- = do { body' <- tcMonoExpr body elt_ty
- ; thing <- thing_inside elt_ty
+tcLcStmt _ _ (LastStmt body _) elt_ty thing_inside
+ = do { body' <- tcMonoExprNC body elt_ty
+ ; thing <- thing_inside (panic "tcLcStmt: thing_inside")
; return (LastStmt body' noSyntaxExpr, thing) }
-- A generator, pat <- rhs
loop ((stmts, names) : pairs)
= do { (stmts', (ids, pairs', thing))
- <- tcStmts ctxt (tcLcStmt m_tc) stmts elt_ty $ \ _elt_ty' ->
+ <- tcStmtsAndThen ctxt (tcLcStmt m_tc) stmts elt_ty $ \ _elt_ty' ->
do { ids <- tcLookupLocalIds names
; (pairs', thing) <- loop pairs
; return (ids, pairs', thing) }
tcLcStmt m_tc ctxt (TransformStmt stmts binders usingExpr maybeByExpr _ _) elt_ty thing_inside = do
(stmts', (binders', usingExpr', maybeByExpr', thing)) <-
- tcStmts (TransformStmtCtxt ctxt) (tcLcStmt m_tc) stmts elt_ty $ \elt_ty' -> do
+ tcStmtsAndThen (TransformStmtCtxt ctxt) (tcLcStmt m_tc) stmts elt_ty $ \elt_ty' -> do
let alphaListTy = mkTyConApp m_tc [alphaTy]
(usingExpr', maybeByExpr') <-
return (TransformStmt stmts' binders' usingExpr' maybeByExpr' noSyntaxExpr noSyntaxExpr, thing)
-tcLcStmt m_tc ctxt (GroupStmt stmts bindersMap by using _ _ _) elt_ty thing_inside
+tcLcStmt m_tc ctxt (GroupStmt { grpS_stmts = stmts, grpS_bndrs = bindersMap
+ , grpS_by = by, grpS_using = using
+ , grpS_explicit = explicit }) elt_ty thing_inside
= do { let (bndr_names, list_bndr_names) = unzip bindersMap
; (stmts', (bndr_ids, by', using_ty, elt_ty')) <-
- tcStmts (TransformStmtCtxt ctxt) (tcLcStmt m_tc) stmts elt_ty $ \elt_ty' -> do
+ tcStmtsAndThen (TransformStmtCtxt ctxt) (tcLcStmt m_tc) stmts elt_ty $ \elt_ty' -> do
(by', using_ty) <-
case by of
Nothing -> -- check that using :: forall a. [a] -> [[a]]
bindersMap' = bndr_ids `zip` list_bndr_ids
-- See Note [GroupStmt binder map] in HsExpr
- ; using' <- case using of
- Left e -> do { e' <- tcPolyExpr e using_ty; return (Left e') }
- Right e -> do { e' <- tcPolyExpr (noLoc e) using_ty; return (Right (unLoc e')) }
+ ; using' <- tcPolyExpr using using_ty
-- Type check the thing in the environment with
-- these new binders and return the result
; thing <- tcExtendIdEnv list_bndr_ids (thing_inside elt_ty')
- ; return (GroupStmt stmts' bindersMap' by' using' noSyntaxExpr noSyntaxExpr noSyntaxExpr, thing) }
+ ; return (emptyGroupStmt { grpS_stmts = stmts', grpS_bndrs = bindersMap'
+ , grpS_by = by', grpS_using = using'
+ , grpS_explicit = explicit }, thing) }
where
alphaListTy = mkTyConApp m_tc [alphaTy]
alphaListListTy = mkTyConApp m_tc [alphaListTy]
tcMcStmt :: TcStmtChecker
-tcMcStmt ctxt (LastStmt body return_op) res_ty thing_inside
+tcMcStmt _ (LastStmt body return_op) res_ty thing_inside
= do { a_ty <- newFlexiTyVarTy liftedTypeKind
; return_op' <- tcSyntaxOp MCompOrigin return_op
(a_ty `mkFunTy` res_ty)
- ; body' <- tcMonoExpr body a_ty
- ; return (body', return_op') }
+ ; body' <- tcMonoExprNC body a_ty
+ ; thing <- thing_inside (panic "tcMcStmt: thing_inside")
+ ; return (LastStmt body' return_op', thing) }
-- Generators for monad comprehensions ( pat <- rhs )
--
-- [ body | stmts, then f by e ] -> f :: forall a. (a -> t) -> m a -> m a
--
tcMcStmt ctxt (TransformStmt stmts binders usingExpr maybeByExpr return_op bind_op) res_ty thing_inside
- = do {
- -- We don't know the types of binders yet, so we use this dummy and
- -- later unify this type with the `m_bndr_ty`
- ty_dummy <- newFlexiTyVarTy liftedTypeKind
+ = do { let star_star_kind = liftedTypeKind `mkArrowKind` liftedTypeKind
+ ; m1_ty <- newFlexiTyVarTy star_star_kind
+ ; m2_ty <- newFlexiTyVarTy star_star_kind
+ ; n_ty <- newFlexiTyVarTy star_star_kind
+ ; tup_ty_var <- newFlexiTyVarTy liftedTypeKind
+ ; new_res_ty <- newFlexiTyVarTy liftedTypeKind
+ ; let m1_tup_ty = m1_ty `mkAppTy` tup_ty_var
+ -- 'stmts' returns a result of type (m1_ty tuple_ty),
+ -- typically something like [(Int,Bool,Int)]
+ -- We don't know what tuple_ty is yet, so we use a variable
; (stmts', (binders', usingExpr', maybeByExpr', return_op', bind_op', thing)) <-
- tcStmts (TransformStmtCtxt ctxt) tcMcStmt stmts ty_dummy $ \res_ty' -> do
- { (_, (m_ty, _)) <- matchExpectedAppTy res_ty'
- ; (usingExpr', maybeByExpr') <-
+ tcStmtsAndThen (TransformStmtCtxt ctxt) tcMcStmt stmts m1_tup_ty $ \res_ty' -> do
+ { (usingExpr', maybeByExpr') <-
case maybeByExpr of
Nothing -> do
-- We must validate that usingExpr :: forall a. m a -> m a
-- [ body | stmts, then group using f ]
-- -> f :: forall a. m a -> m (m a)
--
-tcMcStmt ctxt (GroupStmt stmts bindersMap by using return_op bind_op fmap_op) res_ty thing_inside
- = do { m1_ty <- newFlexiTyVarTy liftedTypeKind
- ; m2_ty <- newFlexiTyVarTy liftedTypeKind
- ; n_ty <- newFlexiTyVarTy liftedTypeKind
+tcMcStmt ctxt (GroupStmt { grpS_stmts = stmts, grpS_bndrs = bindersMap
+ , grpS_by = by, grpS_using = using, grpS_explicit = explicit
+ , grpS_ret = return_op, grpS_bind = bind_op
+ , grpS_fmap = fmap_op }) res_ty thing_inside
+ = do { let star_star_kind = liftedTypeKind `mkArrowKind` liftedTypeKind
+ ; m1_ty <- newFlexiTyVarTy star_star_kind
+ ; m2_ty <- newFlexiTyVarTy star_star_kind
+ ; n_ty <- newFlexiTyVarTy star_star_kind
; tup_ty_var <- newFlexiTyVarTy liftedTypeKind
; new_res_ty <- newFlexiTyVarTy liftedTypeKind
; let (bndr_names, n_bndr_names) = unzip bindersMap
-- typically something like [(Int,Bool,Int)]
-- We don't know what tuple_ty is yet, so we use a variable
; (stmts', (bndr_ids, by_e_ty, return_op')) <-
- tcStmts (TransformStmtCtxt ctxt) tcMcStmt stmts m1_tup_ty $ \res_ty' -> do
- { by_e_ty <- mapM tcInferRhoNC by_e
+ tcStmtsAndThen (TransformStmtCtxt ctxt) tcMcStmt stmts m1_tup_ty $ \res_ty' -> do
+ { by_e_ty <- case by of
+ Nothing -> return Nothing
+ Just e -> do { e_ty <- tcInferRhoNC e; return (Just e_ty) }
-- Find the Ids (and hence types) of all old binders
; bndr_ids <- tcLookupLocalIds bndr_names
using_res_ty = m2_ty `mkAppTy` n_tup_ty -- m2 (n (a,b,c))
using_fun_ty = using_arg_ty `mkFunTy` using_arg_ty
- -- (>>=) :: m2 (n (a,b,c)) -> ( n (a,b,c) -> new_res_ty ) -> res_ty
- -- using :: ((a,b,c)->t) -> m1 (a,b,c) -> m2 (n (a,b,c))
+ -- (>>=) :: m2 (n (a,b,c)) -> ( n (a,b,c) -> new_res_ty ) -> res_ty
+ -- using :: ((a,b,c)->t) -> m1 (a,b,c) -> m2 (n (a,b,c))
--------------- Typecheck the 'bind' function -------------
; bind_op' <- tcSyntaxOp MCompOrigin bind_op $
`mkFunTy` res_ty
--------------- Typecheck the 'using' function -------------
- ; let using_fun_ty = (m1_ty `mkAppTy` alphaTy) `mkFunTy`
+ ; let poly_fun_ty = (m1_ty `mkAppTy` alphaTy) `mkFunTy`
(m2_ty `mkAppTy` (n_ty `mkAppTy` alphaTy))
using_poly_ty = case by_e_ty of
- Nothing -> mkForAllTy alphaTyVar using_fun_ty
+ Nothing -> mkForAllTy alphaTyVar poly_fun_ty
-- using :: forall a. m1 a -> m2 (n a)
Just (_,t_ty) -> mkForAllTy alphaTyVar $
- (alphaTy `mkFunTy` t_ty) `mkFunTy` using_fun_ty
+ (alphaTy `mkFunTy` t_ty) `mkFunTy` poly_fun_ty
-- using :: forall a. (a->t) -> m1 a -> m2 (n a)
-- where by :: t
- ; using' <- case using of
- Left e -> do { e' <- tcPolyExpr e using_poly_ty
- ; return (Left e') }
- Right e -> do { e' <- tcPolyExpr (noLoc e) using_poly_ty
- ; return (Right (unLoc e')) }
+ ; using' <- tcPolyExpr using using_poly_ty
; coi <- unifyType (applyTy using_poly_ty tup_ty)
(case by_e_ty of
Nothing -> using_fun_ty
Just (_,t_ty) -> (tup_ty `mkFunTy` t_ty) `mkFunTy` using_fun_ty)
- ; let final_using = mkHsWrapCoI coi (HsWrap (WpTyApp tup_ty) using')
+ ; let final_using = fmap (mkHsWrapCoI coi . HsWrap (WpTyApp tup_ty)) using'
--------------- Typecheck the 'fmap' function -------------
; fmap_op' <- fmap unLoc . tcPolyExpr (noLoc fmap_op) $
mkForAllTy alphaTyVar $ mkForAllTy betaTyVar $
- (alphaTy `mkFunTy` betaTy)
- `mkFunTy`
- (m_ty `mkAppTy` alphaTy)
- `mkFunTy`
- (m_ty `mkAppTy` betaTy)
+ (alphaTy `mkFunTy` betaTy)
+ `mkFunTy` (n_ty `mkAppTy` alphaTy)
+ `mkFunTy` (n_ty `mkAppTy` betaTy)
; let mk_n_bndr :: Name -> TcId -> TcId
mk_n_bndr n_bndr_name bndr_id
- = mkLocalId bndr_name (n_ty `mkAppTy` idType bndr_id)
+ = mkLocalId n_bndr_name (n_ty `mkAppTy` idType bndr_id)
-- Ensure that every old binder of type `b` is linked up with its
-- new binder which should have type `n b`
-- return the result
; thing <- tcExtendIdEnv n_bndr_ids (thing_inside res_ty)
- ; return (GroupStmt stmts' bindersMap'
- (fmap fst by_e_ty) final_using
- return_op' bind_op' fmap_op', thing) }
+ ; return (GroupStmt { grpS_stmts = stmts', grpS_bndrs = bindersMap'
+ , grpS_by = fmap fst by_e_ty, grpS_using = final_using
+ , grpS_ret = return_op', grpS_bind = bind_op'
+ , grpS_fmap = fmap_op', grpS_explicit = explicit }, thing) }
-- Typecheck `ParStmt`. See `tcLcStmt` for more informations about typechecking
-- of `ParStmt`s.
--
tcMcStmt ctxt (ParStmt bndr_stmts_s mzip_op bind_op return_op) res_ty thing_inside
= do { (_,(m_ty,_)) <- matchExpectedAppTy res_ty
+ -- ToDo: what if the coercion isn't the identity?
+
; (pairs', thing) <- loop m_ty bndr_stmts_s
; let mzip_ty = mkForAllTys [alphaTyVar, betaTyVar] $
; return_op' <- fmap unLoc . tcPolyExpr (noLoc return_op) $
mkForAllTy alphaTyVar $
alphaTy `mkFunTy` (m_ty `mkAppTy` alphaTy)
- ; return_op' <- tcSyntaxOp MCompOrigin return_op
- (bndr_ty `mkFunTy` m_bndr_ty)
; return (ParStmt pairs' mzip_op' bind_op' return_op', thing) }
- where mk_tuple_ty tys = foldr (\tn tm -> mkBoxedTupleTy [tn, tm]) (last tys) (init tys)
+ where mk_tuple_ty tys = foldr1 (\tn tm -> mkBoxedTupleTy [tn, tm]) tys
-- loop :: Type -- m_ty
-- -> [([LStmt Name], [Name])]
= do { -- type dummy since we don't know all binder types yet
ty_dummy <- newFlexiTyVarTy liftedTypeKind
; (stmts', (ids, pairs', thing))
- <- tcStmts ctxt tcMcStmt stmts ty_dummy $ \res_ty' ->
+ <- tcStmtsAndThen ctxt tcMcStmt stmts ty_dummy $ \res_ty' ->
do { ids <- tcLookupLocalIds names
; _ <- unifyType res_ty' (m_ty `mkAppTy` mkBigCoreVarTupTy ids)
; (pairs', thing) <- loop m_ty pairs
tcDoStmt :: TcStmtChecker
-tcDoStmt ctxt (LastStmt body _) res_ty thing_inside
- = do { body' <- tcMonoExpr body res_ty
- ; thing <- thing_inside body_ty
+tcDoStmt _ (LastStmt body _) res_ty thing_inside
+ = do { body' <- tcMonoExprNC body res_ty
+ ; thing <- thing_inside (panic "tcDoStmt: thing_inside")
; return (LastStmt body' noSyntaxExpr, thing) }
tcDoStmt ctxt (BindStmt pat rhs bind_op fail_op) res_ty thing_inside
; tcExtendIdEnv tup_ids $ do
{ stmts_ty <- newFlexiTyVarTy liftedTypeKind
; (stmts', (ret_op', tup_rets))
- <- tcStmts ctxt tcDoStmt stmts stmts_ty $ \ inner_res_ty ->
+ <- tcStmtsAndThen ctxt tcDoStmt stmts stmts_ty $ \ inner_res_ty ->
do { tup_rets <- zipWithM tcCheckId tup_names tup_elt_tys
-- Unify the types of the "final" Ids (which may
-- be polymorphic) with those of "knot-tied" Ids
, recS_rec_ids = recNames }) res_ty thing_inside
= do { rec_tys <- newFlexiTyVarTys (length recNames) liftedTypeKind
; let rec_ids = zipWith mkLocalId recNames rec_tys
- ; tcExtendIdEnv rec_ids $ do
+ ; tcExtendIdEnv rec_ids $ do
{ (stmts', (later_ids, rec_rets))
- <- tcStmts ctxt (tcMDoStmt tc_rhs) stmts res_ty $ \ _res_ty' ->
+ <- tcStmtsAndThen ctxt (tcMDoStmt tc_rhs) stmts res_ty $ \ _res_ty' ->
-- ToDo: res_ty not really right
do { rec_rets <- zipWithM tcCheckId recNames rec_tys
; later_ids <- tcLookupLocalIds laterNames
-- some of them with polymorphic things with the same Name
-- (see note [RecStmt] in HsExpr)
- ; return (RecStmt stmts' later_ids rec_ids noSyntaxExpr noSyntaxExpr noSyntaxExpr rec_rets, thing)
+ ; return (emptyRecStmt { recS_stmts = stmts', recS_later_ids = later_ids
+ , recS_rec_ids = rec_ids, recS_rec_rets = rec_rets
+ , recS_ret_ty = res_ty }, thing)
}}
tcMDoStmt _ _ stmt _ _
= pprPanic "tcMDoStmt: unexpected Stmt" (ppr stmt)
-
\end{code}