* Appel's
*)
val transExp : env:Env.t -> A.exp -> expty
- val transVar : env:Env.t -> A.var -> expty
- val transDec : env:Env.t -> A.dec -> Env.t
- val transTy : env:Env.t -> A.ty -> Type.t (* needs only type env *)
+
+ (* transVar does not seem to be needed, as trvar handles all our cases.
+ * Am I wrong?
+ *
+ * val transVar : env:Env.t -> A.var -> expty
+ *
+ *)
end = struct
type expty =
{ exp : Translate.exp
; ty : Type.t
}
- let unimplemented () =
- failwith "unimplemented"
-
let return ty = {exp = (); ty}
let return_unit = return Type.Unit
let return_nil = return Type.Nil
check_same {exp=(); ty=Type.Int} expty ~pos
(* TODO: actual_ty *)
+ (* TODO: mutual recursion *)
let rec transExp ~env exp =
let rec trexp exp =
E.raise (E.Wrong_type_used_as_record {ty_id=typ; ty; pos})
);
return ty
- | A.SeqExp exps ->
- (* Ignoring value because we only care if a type-checking exception
- * is raised in one of trexp calls: *)
- List.iter exps ~f:(fun (exp, _) -> ignore (trexp exp));
+ | A.SeqExp [] ->
return_unit
+ | A.SeqExp exps ->
+ let last xs =
+ xs
+ |> List.rev (* Yes, redundant, but clean-looking ;-P *)
+ |> List.hd (* Empty is matched in above SeqExp match case *)
+ in
+ exps
+ |> List.map ~f:(fun (exp, _) -> let {ty; _} = trexp exp in ty)
+ |> last
+ |> return
| A.AssignExp {var; exp; pos} ->
check_same (trvar var) (trexp exp) ~pos;
(* TODO: Add var->exp to val env? *)
check_int (trexp lo) ~pos;
check_int (trexp hi) ~pos;
(* Only care if a type-error is raised *)
- ignore (transExp ~env:(Env.set_typ env var Type.Int) body);
+ let env = Env.set_val env var (Value.Var {ty = Type.Int}) in
+ ignore (transExp ~env body);
return_unit
| A.BreakExp _ ->
return_unit
- | A.LetExp {decs=_; body=_; _} ->
- unimplemented ()
+ | A.LetExp {decs; body; pos=_} ->
+ (* (1) decs augment env *)
+ (* (2) body checked against the new env *)
+ let env =
+ List.fold_left decs ~init:env ~f:(fun env dec -> transDec dec ~env)
+ in
+ transExp body ~env
| A.ArrayExp {typ; size; init; pos} ->
check_int (trexp size) ~pos;
let ty = env_get_typ ~sym:typ ~env ~pos in
)
in
trexp exp
-
- let transVar ~env:_ var =
- (match var with
- | A.SimpleVar {symbol=_; _} ->
- unimplemented ()
- | A.FieldVar {var=_; symbol=_; _} ->
- unimplemented ()
- | A.SubscriptVar {var=_; exp=_; _} ->
- unimplemented ()
- )
-
- let transDec ~env:_ dec =
+ and transDec ~(env : Env.t) (dec : A.dec) : Env.t =
(match dec with
- | A.VarDec {name=_; typ=_; init=_; pos=_; escape=_} ->
- unimplemented ()
- | A.TypeDecs _ ->
- unimplemented ()
- | A.FunDecs _ ->
- unimplemented ()
+ | A.VarDec {name; typ=typ_opt; init; pos=pos_outter; escape=_} ->
+ let ty =
+ (match (typ_opt, transExp ~env init) with
+ | None, {ty; exp=()} ->
+ ty
+ | Some (sym, pos_inner), expty_init ->
+ let ty = env_get_typ ~sym ~env ~pos:pos_inner in
+ check_same {exp=(); ty} expty_init ~pos:pos_outter;
+ ty
+ )
+ in
+ Env.set_val env name (Value.Var {ty})
+ | A.TypeDecs typedecs ->
+ List.fold_left typedecs ~init:env ~f:(
+ fun env (A.TypeDec {name; ty; pos=_}) ->
+ let ty = transTy ~env ty in
+ Env.set_typ env name ty
+ )
+ | A.FunDecs fundecs ->
+ List.fold_left fundecs ~init:env ~f:(
+ fun env (A.FunDec {name; params; result; body; pos=_}) ->
+ let (env_for_body, formals_in_reverse_order) =
+ List.fold_left params ~init:(env, []) ~f:(
+ fun (env, formals) (A.Field {name; escape=_; typ; pos}) ->
+ let ty = env_get_typ ~env ~sym:typ ~pos in
+ let env = Env.set_val env name (Value.Var {ty}) in
+ (env, ty :: formals)
+ )
+ in
+ (* ignore because we only care if an exception is raised *)
+ ignore (transExp ~env:env_for_body body);
+ let formals = List.rev formals_in_reverse_order in
+ let result =
+ match result with
+ | None ->
+ Type.Unit
+ | Some (sym, pos) ->
+ env_get_typ ~sym ~env ~pos
+ in
+ Env.set_val env name (Value.Fun {formals; result})
+ )
)
-
- let transTy ~env:_ typ =
+ and transTy ~(env : Env.t) (typ : A.ty) : Type.t =
(match typ with
- | A.NameTy {symbol = _; pos = _} ->
- unimplemented ()
- | A.RecordTy _ ->
- unimplemented ()
- | A.ArrayTy {symbol = _; pos = _} ->
- unimplemented ()
+ | A.NameTy {symbol=sym; pos} ->
+ env_get_typ ~sym ~env ~pos
+ | A.RecordTy fields ->
+ let fields =
+ List.map fields ~f:(fun (A.Field {name; escape=_; typ; pos}) ->
+ let ty = env_get_typ ~sym:typ ~env ~pos in
+ (name, ty)
+ )
+ in
+ Type.new_record fields
+ | A.ArrayTy {symbol=sym; pos} ->
+ let element_ty = env_get_typ ~sym ~env ~pos in
+ Type.new_array element_ty
)
end
+open Semant
+
let transProg absyn =
- let open Semant in
let {exp = _; ty = _} = transExp absyn ~env:Env.base in
()