[tiger.ml.git] / compiler / src / lib / tiger / tiger_semant.ml

module List = ListLabels

module A         = Tiger_absyn
module Env       = Tiger_env
module E         = Tiger_error
module Translate = Tiger_translate
module Type      = Tiger_env_type
module Value     = Tiger_env_value

(* The only reason for having this seemingly-superfluous inner module is to
 * have this nice signature as a summary of what each function does. *)
module Semant : sig
  type expty =
    { exp : Translate.exp
    ; ty  : Type.t
    }

  (* Violating normal naming convention just to make it easier to follow
   * Appel's
   *)
  val transExp : env:Env.t -> A.exp -> expty

  (* 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 rec actual_ty ty ~pos =
    match ty with
    | Type.Name (name, ty_opt_ref) ->
        (match !ty_opt_ref with
        | None ->
            E.raise (E.Unknown_type {ty_id=name; pos})
        | Some ty ->
            actual_ty ty ~pos
        )
    | Type.Unit
    | Type.Nil
    | Type.Int
    | Type.String
    | Type.Record _
    | Type.Array _ ->
        ty

  let return ty     = {exp = (); ty}
  let return_unit   = return Type.Unit
  let return_nil    = return Type.Nil
  let return_int    = return Type.Int
  let return_string = return Type.String

  let env_get_typ ~sym ~env ~pos : Type.t =
    match Env.get_typ env sym with
    | Some ty -> ty
    | None    -> E.raise (E.Unknown_type {ty_id=sym; pos})

  let env_get_typ_actual ~sym ~env ~pos : Type.t =
    actual_ty (env_get_typ ~sym ~env ~pos) ~pos

  let env_get_val ~sym ~env ~pos : Value.t =
    match Env.get_val env sym with
    | Some ty -> ty
    | None    -> E.raise (E.Unknown_id {id=sym; pos})

  let check_same {exp=_; ty=ty_left} {exp=_; ty=ty_right} ~pos : unit =
    if Type.is_equal ty_left ty_right then
      ()
    else
      E.raise (E.Wrong_type {expected=ty_left; given=ty_right; pos})

  let check_int expty ~pos : unit =
    check_same return_int expty ~pos

  let rec transExp ~env exp =
    let rec trexp exp =
      (match exp with
      | A.NilExp ->
          return_nil
      | A.IntExp _ ->
          return_int
      | A.StringExp {string=_; _} ->
          return_string
      | A.CallExp {func; args; pos} ->
          (match env_get_val ~sym:func ~env ~pos with
          | Value.Fun {formals; result} ->
              let expected = List.length formals in
              let given    = List.length args in
              if given = expected then
                begin
                  List.iter2 formals args ~f:(fun ty_expected exp_given ->
                    check_same
                      (return (actual_ty ~pos ty_expected))
                      (trexp exp_given)
                      ~pos;
                  );
                  return (actual_ty ~pos result)
                end
              else
                E.raise (E.Wrong_number_of_args {func; expected; given; pos})
          | Value.Var _ ->
              E.raise (E.Id_not_a_function {id=func; pos})
          )
      | A.OpExp {oper; left; right; pos} ->
          trop oper ~left ~right ~pos
      | A.RecordExp {fields=field_exps; typ; pos} ->
          let ty = env_get_typ_actual ~sym:typ ~env ~pos in
          Type.if_record
            ty
            ~f:(fun field_tys ->
              List.iter field_exps ~f:(fun (field, exp, pos) ->
                (match List.assoc_opt field field_tys with
                | Some field_ty ->
                    check_same (return (actual_ty ~pos field_ty)) (trexp exp) ~pos
                | None ->
                    E.raise
                      (E.No_such_field_in_record {field; record=ty; pos})
                )
              )
            )
            ~otherwise:(fun () ->
              E.raise (E.Wrong_type_used_as_record {ty_id=typ; ty; pos})
            );
          return (actual_ty ~pos ty)
      | 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, _) -> trexp exp)
          |> last
      | A.AssignExp {var; exp; pos} ->
          check_same (trvar var) (trexp exp) ~pos;
          (* TODO: Add var->exp to val env? *)
          return_unit
      | A.IfExp {test; then'; else'; pos} ->
          (* test : must be int, because we have no bool *)
          (* then : must equal else *)
          (* else : must equal then or be None *)
          check_int (trexp test) ~pos;
          (match (trexp then', else') with
          | expty_then, None ->
              expty_then
          | expty_then, Some else' ->
              let expty_else = trexp else' in
              check_same expty_then expty_else ~pos;
              expty_then
          )
      | A.WhileExp {test; body; pos} ->
          (* test : must be int, because we have no bool *)
          check_int (trexp test) ~pos;
          ignore (trexp body);  (* Only care if a type-error is raised *)
          return_unit
      | A.ForExp {var; lo; hi; body; pos; escape=_} ->
          check_int (trexp lo) ~pos;
          check_int (trexp hi) ~pos;
          (* Only care if a type-error is raised *)
          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; 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_actual ~sym:typ ~env ~pos in
          Type.if_array
            ty
            ~f:(fun ty_elements ->
              check_same (return (actual_ty ~pos ty_elements)) (trexp init) ~pos
            )
            ~otherwise:(fun () ->
              E.raise (E.Wrong_type_used_as_array {ty_id=typ; ty; pos})
            );
          return (actual_ty ~pos ty)
      | A.VarExp var ->
          trvar var
      )
    and trvar =
      (function
      | A.SimpleVar {symbol=sym; pos} ->
          (match env_get_val ~sym ~env ~pos with
          | Value.Fun _    -> E.raise (E.Id_is_a_function {id=sym; pos})
          | Value.Var {ty} -> return (actual_ty ~pos ty)
          )
      | A.FieldVar {var; symbol; pos} ->
          let {exp=_; ty} = trvar var in
          Type.if_record
            ty
            ~f:(fun fields ->
              (match List.assoc_opt symbol fields with
              | None ->
                  E.raise
                    (E.No_such_field_in_record {field=symbol; record=ty; pos})
              | Some ty ->
                  return (actual_ty ~pos ty)
              )
            )
            ~otherwise:(fun () -> E.raise (E.Exp_not_a_record {ty; pos}))
      | A.SubscriptVar {var; exp; pos} ->
          let {exp=_; ty} = trvar var in
          check_int (trexp exp) ~pos;
          Type.if_array
            ty
            ~f:(fun ty_elements -> return (actual_ty ~pos ty_elements))
            ~otherwise:(fun () -> E.raise (E.Exp_not_an_array {ty; pos}))
      )
    and trop oper ~left ~right ~pos =
      (* TODO: Refactor trop - all opers return bool/int *)
      let expty_left  = trexp left in
      let expty_right = trexp right in
      check_same expty_left expty_right ~pos;
      let {exp=_; ty} = expty_left in
      let module T = Type in
      (match oper with
      (* Arithmetic: int *)
      | A.PlusOp
      | A.MinusOp
      | A.TimesOp
      | A.DivideOp ->
          check_int expty_left ~pos;
          return_int
      (* Equality: int, string, array, record *)
      | A.EqOp
      | A.NeqOp ->
          if (T.is_int    ty)
          || (T.is_string ty)
          || (T.is_array  ty)
          || (T.is_record ty)
          then
            return_int  (* Because we have no bool type *)
          else
            E.raise (E.Invalid_operand_type
              { oper
              ; valid = ["int"; "string"; "array"; "record"]
              ; given = ty
              ; pos
              })
      (* Order: int, string *)
      | A.LtOp
      | A.LeOp
      | A.GtOp
      | A.GeOp ->
          if (T.is_int    ty)
          || (T.is_string ty)
          then
            return_int  (* Because we have no bool type *)
          else
            E.raise (E.Invalid_operand_type
              { oper
              ; valid = ["int"; "string"]
              ; given = ty
              ; pos
              })
      )
    in
    trexp exp
  and transDec ~(env : Env.t) (dec : A.dec) : Env.t =
    (match dec with
    | 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_actual ~sym ~env ~pos:pos_inner in
              check_same (return ty) expty_init ~pos:pos_outter;
              ty
          )
        in
        Env.set_val env name (Value.Var {ty})
    | A.TypeDecs typedecs ->
        let env =
          List.fold_left typedecs ~init:env ~f:(
            fun env (A.TypeDec {name; ty=_; pos=_}) ->
              Env.set_typ env name (Type.Name (name, ref None))
          )
        in
        List.iter typedecs ~f:(fun (A.TypeDec {name; ty=ty_exp; pos}) ->
          let ty = transTy ~env ty_exp in
          (match env_get_typ ~sym:name ~env ~pos with
          | Type.Name (_, ty_opt_ref) ->
              ty_opt_ref := Some ty
          | Type.Unit
          | Type.Nil
          | Type.Int
          | Type.String
          | Type.Record _
          | Type.Array _ ->
              ()
          )
        );
        env
    | A.FunDecs fundecs ->
        let env_with_fun_heads_only =
          List.fold_left fundecs ~init:env ~f:(
            fun env (A.FunDec {name; params; result; body=_; pos=_}) ->
              let formals =
                List.map params ~f:(
                  fun (A.Field {name=_; typ; pos; escape=_}) ->
                    env_get_typ_actual ~env ~sym:typ ~pos
                )
              in
              let result =
                match result with
                | Some (s, p) -> env_get_typ_actual ~sym:s ~env ~pos:p
                | None        -> Type.Unit
              in
              Env.set_val env name (Value.Fun {formals; result})
          )
        in
        List.iter fundecs ~f:(
          fun (A.FunDec {name=_; params; result=_; body; pos=_}) ->
            let env_with_fun_heads_and_local_vars =
              List.fold_left params ~init:env_with_fun_heads_only ~f:(
                fun env (A.Field {name=var_name; escape=_; typ; pos}) ->
                  let var_ty = env_get_typ_actual ~env ~sym:typ ~pos in
                  Env.set_val env var_name (Value.Var {ty = var_ty})
              )
            in
            (* we only care if an exception is raised *)
            ignore (transExp ~env:env_with_fun_heads_and_local_vars body);
        );
        env_with_fun_heads_only
    )
  and transTy ~(env : Env.t) (ty_exp : A.ty) : Type.t =
    (match ty_exp with
    | 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 {exp = _; ty = _} = transExp absyn ~env:Env.base in
  ()
Commit	Line	Data
523e2b06 SK	1	module List = ListLabels
523e2b06 SK	2
155ee327 SK	3	module A = Tiger_absyn
	4	module Env = Tiger_env
	5	module E = Tiger_error
155ee327 SK	6	module Translate = Tiger_translate
	7	module Type = Tiger_env_type
	8	module Value = Tiger_env_value
	9
	10	(* The only reason for having this seemingly-superfluous inner module is to
	11	* have this nice signature as a summary of what each function does. *)
	12	module Semant : sig
	13	type expty =
	14	{ exp : Translate.exp
	15	; ty : Type.t
	16	}
	17
	18	(* Violating normal naming convention just to make it easier to follow
	19	* Appel's
	20	*)
	21	val transExp : env:Env.t -> A.exp -> expty
862e5c05 SK	22
	23	(* transVar does not seem to be needed, as trvar handles all our cases.
	24	* Am I wrong?
	25	*
	26	* val transVar : env:Env.t -> A.var -> expty
	27	*
	28	*)
155ee327 SK	29	end = struct
	30	type expty =
	31	{ exp : Translate.exp
	32	; ty : Type.t
	33	}
	34
cbb4ffb6 SK	35	let rec actual_ty ty ~pos =
	36	match ty with
	37	\| Type.Name (name, ty_opt_ref) ->
	38	(match !ty_opt_ref with
	39	\| None ->
	40	E.raise (E.Unknown_type {ty_id=name; pos})
	41	\| Some ty ->
	42	actual_ty ty ~pos
	43	)
	44	\| Type.Unit
	45	\| Type.Nil
	46	\| Type.Int
	47	\| Type.String
	48	\| Type.Record _
	49	\| Type.Array _ ->
	50	ty
	51
523e2b06 SK	52	let return ty = {exp = (); ty}
	53	let return_unit = return Type.Unit
	54	let return_nil = return Type.Nil
	55	let return_int = return Type.Int
	56	let return_string = return Type.String
155ee327	57
523e2b06 SK	58	let env_get_typ ~sym ~env ~pos : Type.t =
	59	match Env.get_typ env sym with
	60	\| Some ty -> ty
	61	\| None -> E.raise (E.Unknown_type {ty_id=sym; pos})
	62
cbb4ffb6 SK	63	let env_get_typ_actual ~sym ~env ~pos : Type.t =
	64	actual_ty (env_get_typ ~sym ~env ~pos) ~pos
	65
523e2b06 SK	66	let env_get_val ~sym ~env ~pos : Value.t =
	67	match Env.get_val env sym with
	68	\| Some ty -> ty
	69	\| None -> E.raise (E.Unknown_id {id=sym; pos})
	70
	71	let check_same {exp=_; ty=ty_left} {exp=_; ty=ty_right} ~pos : unit =
	72	if Type.is_equal ty_left ty_right then
	73	()
	74	else
	75	E.raise (E.Wrong_type {expected=ty_left; given=ty_right; pos})
	76
	77	let check_int expty ~pos : unit =
cbb4ffb6	78	check_same return_int expty ~pos
978cb41c	79
523e2b06 SK	80	let rec transExp ~env exp =
	81	let rec trexp exp =
	82	(match exp with
	83	\| A.NilExp ->
	84	return_nil
	85	\| A.IntExp _ ->
	86	return_int
	87	\| A.StringExp {string=_; _} ->
	88	return_string
978cb41c SK	89	\| A.CallExp {func; args; pos} ->
	90	(match env_get_val ~sym:func ~env ~pos with
	91	\| Value.Fun {formals; result} ->
54e838f4 SK	92	let expected = List.length formals in
	93	let given = List.length args in
	94	if given = expected then
	95	begin
	96	List.iter2 formals args ~f:(fun ty_expected exp_given ->
	97	check_same
	98	(return (actual_ty ~pos ty_expected))
	99	(trexp exp_given)
	100	~pos;
	101	);
	102	return (actual_ty ~pos result)
	103	end
	104	else
	105	E.raise (E.Wrong_number_of_args {func; expected; given; pos})
978cb41c SK	106	\| Value.Var _ ->
	107	E.raise (E.Id_not_a_function {id=func; pos})
	108	)
523e2b06 SK	109	\| A.OpExp {oper; left; right; pos} ->
523e2b06 SK	110	trop oper ~left ~right ~pos
0ed7a07c	111	\| A.RecordExp {fields=field_exps; typ; pos} ->
cbb4ffb6	112	let ty = env_get_typ_actual ~sym:typ ~env ~pos in
0ed7a07c SK	113	Type.if_record
	114	ty
	115	~f:(fun field_tys ->
	116	List.iter field_exps ~f:(fun (field, exp, pos) ->
	117	(match List.assoc_opt field field_tys with
	118	\| Some field_ty ->
cbb4ffb6	119	check_same (return (actual_ty ~pos field_ty)) (trexp exp) ~pos
0ed7a07c SK	120	\| None ->
	121	E.raise
	122	(E.No_such_field_in_record {field; record=ty; pos})
	123	)
	124	)
	125	)
	126	~otherwise:(fun () ->
	127	E.raise (E.Wrong_type_used_as_record {ty_id=typ; ty; pos})
	128	);
cbb4ffb6	129	return (actual_ty ~pos ty)
9d8471b2	130	\| A.SeqExp [] ->
523e2b06	131	return_unit
9d8471b2 SK	132	\| A.SeqExp exps ->
	133	let last xs =
	134	xs
	135	\|> List.rev (* Yes, redundant, but clean-looking ;-P *)
	136	\|> List.hd (* Empty is matched in above SeqExp match case *)
	137	in
	138	exps
cbb4ffb6	139	\|> List.map ~f:(fun (exp, _) -> trexp exp)
9d8471b2	140	\|> last
523e2b06 SK	141	\| A.AssignExp {var; exp; pos} ->
	142	check_same (trvar var) (trexp exp) ~pos;
	143	(* TODO: Add var->exp to val env? *)
	144	return_unit
	145	\| A.IfExp {test; then'; else'; pos} ->
	146	(* test : must be int, because we have no bool *)
	147	(* then : must equal else *)
	148	(* else : must equal then or be None *)
	149	check_int (trexp test) ~pos;
	150	(match (trexp then', else') with
	151	\| expty_then, None ->
	152	expty_then
	153	\| expty_then, Some else' ->
	154	let expty_else = trexp else' in
	155	check_same expty_then expty_else ~pos;
	156	expty_then
	157	)
	158	\| A.WhileExp {test; body; pos} ->
	159	(* test : must be int, because we have no bool *)
	160	check_int (trexp test) ~pos;
	161	ignore (trexp body); (* Only care if a type-error is raised *)
	162	return_unit
	163	\| A.ForExp {var; lo; hi; body; pos; escape=_} ->
	164	check_int (trexp lo) ~pos;
	165	check_int (trexp hi) ~pos;
	166	(* Only care if a type-error is raised *)
85e08b69 SK	167	let env = Env.set_val env var (Value.Var {ty = Type.Int}) in
85e08b69 SK	168	ignore (transExp ~env body);
523e2b06 SK	169	return_unit
	170	\| A.BreakExp _ ->
	171	return_unit
8744eb3a SK	172	\| A.LetExp {decs; body; pos=_} ->
	173	(* (1) decs augment env *)
	174	(* (2) body checked against the new env *)
	175	let env =
	176	List.fold_left decs ~init:env ~f:(fun env dec -> transDec dec ~env)
	177	in
	178	transExp body ~env
4c550cd5 SK	179	\| A.ArrayExp {typ; size; init; pos} ->
4c550cd5 SK	180	check_int (trexp size) ~pos;
cbb4ffb6	181	let ty = env_get_typ_actual ~sym:typ ~env ~pos in
4c550cd5 SK	182	Type.if_array
	183	ty
	184	~f:(fun ty_elements ->
cbb4ffb6	185	check_same (return (actual_ty ~pos ty_elements)) (trexp init) ~pos
4c550cd5 SK	186	)
	187	~otherwise:(fun () ->
	188	E.raise (E.Wrong_type_used_as_array {ty_id=typ; ty; pos})
	189	);
cbb4ffb6	190	return (actual_ty ~pos ty)
523e2b06 SK	191	\| A.VarExp var ->
	192	trvar var
	193	)
	194	and trvar =
	195	(function
	196	\| A.SimpleVar {symbol=sym; pos} ->
	197	(match env_get_val ~sym ~env ~pos with
	198	\| Value.Fun _ -> E.raise (E.Id_is_a_function {id=sym; pos})
cbb4ffb6	199	\| Value.Var {ty} -> return (actual_ty ~pos ty)
523e2b06 SK	200	)
	201	\| A.FieldVar {var; symbol; pos} ->
	202	let {exp=_; ty} = trvar var in
	203	Type.if_record
	204	ty
	205	~f:(fun fields ->
	206	(match List.assoc_opt symbol fields with
	207	\| None ->
	208	E.raise
	209	(E.No_such_field_in_record {field=symbol; record=ty; pos})
	210	\| Some ty ->
cbb4ffb6	211	return (actual_ty ~pos ty)
523e2b06 SK	212	)
	213	)
	214	~otherwise:(fun () -> E.raise (E.Exp_not_a_record {ty; pos}))
161a300d SK	215	\| A.SubscriptVar {var; exp; pos} ->
	216	let {exp=_; ty} = trvar var in
	217	check_int (trexp exp) ~pos;
	218	Type.if_array
	219	ty
cbb4ffb6	220	~f:(fun ty_elements -> return (actual_ty ~pos ty_elements))
161a300d	221	~otherwise:(fun () -> E.raise (E.Exp_not_an_array {ty; pos}))
523e2b06 SK	222	)
523e2b06 SK	223	and trop oper ~left ~right ~pos =
cbb4ffb6	224	(* TODO: Refactor trop - all opers return bool/int *)
523e2b06 SK	225	let expty_left = trexp left in
	226	let expty_right = trexp right in
	227	check_same expty_left expty_right ~pos;
	228	let {exp=_; ty} = expty_left in
	229	let module T = Type in
	230	(match oper with
	231	(* Arithmetic: int *)
	232	\| A.PlusOp
	233	\| A.MinusOp
	234	\| A.TimesOp
	235	\| A.DivideOp ->
	236	check_int expty_left ~pos;
	237	return_int
	238	(* Equality: int, string, array, record *)
	239	\| A.EqOp
	240	\| A.NeqOp ->
	241	if (T.is_int ty)
	242	\|\| (T.is_string ty)
	243	\|\| (T.is_array ty)
	244	\|\| (T.is_record ty)
	245	then
cbb4ffb6	246	return_int (* Because we have no bool type *)
523e2b06 SK	247	else
	248	E.raise (E.Invalid_operand_type
	249	{ oper
	250	; valid = ["int"; "string"; "array"; "record"]
	251	; given = ty
	252	; pos
	253	})
	254	(* Order: int, string *)
	255	\| A.LtOp
	256	\| A.LeOp
	257	\| A.GtOp
	258	\| A.GeOp ->
	259	if (T.is_int ty)
	260	\|\| (T.is_string ty)
	261	then
cbb4ffb6	262	return_int (* Because we have no bool type *)
523e2b06 SK	263	else
	264	E.raise (E.Invalid_operand_type
	265	{ oper
	266	; valid = ["int"; "string"]
	267	; given = ty
	268	; pos
	269	})
	270	)
	271	in
	272	trexp exp
862e5c05	273	and transDec ~(env : Env.t) (dec : A.dec) : Env.t =
8744eb3a SK	274	(match dec with
	275	\| A.VarDec {name; typ=typ_opt; init; pos=pos_outter; escape=_} ->
	276	let ty =
	277	(match (typ_opt, transExp ~env init) with
	278	\| None, {ty; exp=()} ->
	279	ty
	280	\| Some (sym, pos_inner), expty_init ->
cbb4ffb6 SK	281	let ty = env_get_typ_actual ~sym ~env ~pos:pos_inner in
cbb4ffb6 SK	282	check_same (return ty) expty_init ~pos:pos_outter;
8744eb3a SK	283	ty
	284	)
	285	in
	286	Env.set_val env name (Value.Var {ty})
0324a942	287	\| A.TypeDecs typedecs ->
cbb4ffb6 SK	288	let env =
	289	List.fold_left typedecs ~init:env ~f:(
	290	fun env (A.TypeDec {name; ty=_; pos=_}) ->
	291	Env.set_typ env name (Type.Name (name, ref None))
	292	)
	293	in
	294	List.iter typedecs ~f:(fun (A.TypeDec {name; ty=ty_exp; pos}) ->
	295	let ty = transTy ~env ty_exp in
	296	(match env_get_typ ~sym:name ~env ~pos with
9340b0e3	297	\| Type.Name (_, ty_opt_ref) ->
cbb4ffb6 SK	298	ty_opt_ref := Some ty
	299	\| Type.Unit
	300	\| Type.Nil
	301	\| Type.Int
	302	\| Type.String
	303	\| Type.Record _
	304	\| Type.Array _ ->
	305	()
	306	)
	307	);
	308	env
76c771a7	309	\| A.FunDecs fundecs ->
a284f5c2 SK	310	let env_with_fun_heads_only =
	311	List.fold_left fundecs ~init:env ~f:(
	312	fun env (A.FunDec {name; params; result; body=_; pos=_}) ->
	313	let formals =
	314	List.map params ~f:(
	315	fun (A.Field {name=_; typ; pos; escape=_}) ->
	316	env_get_typ_actual ~env ~sym:typ ~pos
	317	)
	318	in
	319	let result =
	320	match result with
	321	\| Some (s, p) -> env_get_typ_actual ~sym:s ~env ~pos:p
	322	\| None -> Type.Unit
	323	in
	324	Env.set_val env name (Value.Fun {formals; result})
	325	)
	326	in
	327	List.iter fundecs ~f:(
	328	fun (A.FunDec {name=_; params; result=_; body; pos=_}) ->
	329	let env_with_fun_heads_and_local_vars =
	330	List.fold_left params ~init:env_with_fun_heads_only ~f:(
	331	fun env (A.Field {name=var_name; escape=_; typ; pos}) ->
	332	let var_ty = env_get_typ_actual ~env ~sym:typ ~pos in
	333	Env.set_val env var_name (Value.Var {ty = var_ty})
76c771a7 SK	334	)
76c771a7 SK	335	in
a284f5c2 SK	336	(* we only care if an exception is raised *)
	337	ignore (transExp ~env:env_with_fun_heads_and_local_vars body);
	338	);
	339	env_with_fun_heads_only
8744eb3a	340	)
cbb4ffb6 SK	341	and transTy ~(env : Env.t) (ty_exp : A.ty) : Type.t =
cbb4ffb6 SK	342	(match ty_exp with
0324a942 SK	343	\| A.NameTy {symbol=sym; pos} ->
	344	env_get_typ ~sym ~env ~pos
	345	\| A.RecordTy fields ->
	346	let fields =
	347	List.map fields ~f:(fun (A.Field {name; escape=_; typ; pos}) ->
	348	let ty = env_get_typ ~sym:typ ~env ~pos in
	349	(name, ty)
	350	)
	351	in
	352	Type.new_record fields
	353	\| A.ArrayTy {symbol=sym; pos} ->
	354	let element_ty = env_get_typ ~sym ~env ~pos in
	355	Type.new_array element_ty
	356	)
155ee327 SK	357	end
155ee327 SK	358
8744eb3a SK	359	open Semant
8744eb3a SK	360
155ee327	361	let transProg absyn =
155ee327 SK	362	let {exp = _; ty = _} = transExp absyn ~env:Env.base in
155ee327 SK	363	()