mlw_typing.ml 81.3 KB
Newer Older
Andrei Paskevich's avatar
Andrei Paskevich committed
1 2 3
(********************************************************************)
(*                                                                  *)
(*  The Why3 Verification Platform   /   The Why3 Development Team  *)
4
(*  Copyright 2010-2013   --   INRIA - CNRS - Paris-Sud University  *)
Andrei Paskevich's avatar
Andrei Paskevich committed
5 6 7 8 9 10
(*                                                                  *)
(*  This software is distributed under the terms of the GNU Lesser  *)
(*  General Public License version 2.1, with the special exception  *)
(*  on linking described in file LICENSE.                           *)
(*                                                                  *)
(********************************************************************)
11

12
open Stdlib
13
open Ident
14 15 16
open Ty
open Term
open Decl
17 18 19
open Theory
open Env
open Ptree
20
open Mlw_dtree
21
open Mlw_ty
22
open Mlw_ty.T
23 24
open Mlw_expr
open Mlw_decl
25
open Mlw_pretty
26
open Mlw_module
Andrei Paskevich's avatar
Andrei Paskevich committed
27
open Mlw_wp
28
open Mlw_dty
29

30 31
(** errors *)

32
exception DuplicateProgVar of string
33 34 35 36 37 38
exception DuplicateTypeVar of string
exception UnboundTypeVar of string

let error = Loc.error
let errorm = Loc.errorm

39 40
let qloc = Typing.qloc
let print_qualid = Typing.print_qualid
41 42 43

let () = Exn_printer.register (fun fmt e -> match e with
  | DuplicateTypeVar s ->
44 45 46
      Format.fprintf fmt "Type parameter %s is used twice" s
  | DuplicateProgVar s ->
      Format.fprintf fmt "Parameter %s is used twice" s
47 48
  | UnboundTypeVar s ->
      Format.fprintf fmt "Unbound type variable '%s" s
49 50 51
  | TooLateInvariant ->
      Format.fprintf fmt
        "Cannot add a type invariant after another program declaration"
52 53 54
  | _ -> raise e)

(* TODO: let type_only = Debug.test_flag Typing.debug_type_only in *)
55 56
let implicit_post = Debug.register_flag "implicit_post"
  ~desc:"Generate@ a@ postcondition@ for@ pure@ functions@ without@ one."
57

58 59
type denv = {
  uc     : module_uc;
60
  locals : (tvars option * dvty) Mstr.t;
61
  tvars  : tvars;
Andrei Paskevich's avatar
Andrei Paskevich committed
62
  uloc   : Ptree.loc option;
63
}
64

65 66 67 68
let create_denv uc = {
  uc     = uc;
  locals = Mstr.empty;
  tvars  = empty_tvars;
Andrei Paskevich's avatar
Andrei Paskevich committed
69
  uloc   = None;
70
}
71

72 73
(* Handle tuple symbols *)

74 75 76
let ht_tuple   = Hint.create 3
let ts_tuple n = Hint.replace ht_tuple n (); ts_tuple n
let fs_tuple n = Hint.replace ht_tuple n (); fs_tuple n
77

78
let check_at f0 =
Andrei Paskevich's avatar
Andrei Paskevich committed
79 80 81 82 83 84 85 86 87 88 89 90
  let rec check f = match f.t_node with
    | Term.Tapp (ls, _) when ls_equal ls fs_at ->
        let d = Mvs.set_diff f.t_vars f0.t_vars in
        if not (Mvs.is_empty d) then errorm ?loc:f.t_loc
          "locally bound variable %a under `at'"
          Pretty.print_vs (fst (Mvs.choose d))
        else true
    | _ ->
        t_all check f
  in
  ignore (check f0)

91 92
let count_term_tuples t =
  let syms_ts _ ts = match is_ts_tuple_id ts.ts_name with
93
    | Some n -> Hint.replace ht_tuple n () | _ -> () in
94 95 96
  let syms_ty _ ty = ty_s_fold syms_ts () ty in
  t_s_fold syms_ty (fun _ _ -> ()) () t

97
let flush_tuples uc =
98 99
  let kn = Theory.get_known (get_theory uc) in
  let add_tuple n _ uc =
Andrei Paskevich's avatar
Andrei Paskevich committed
100
    if Mid.mem (Ty.ts_tuple n).ts_name kn then uc
101
    else use_export_theory uc (tuple_theory n) in
102 103
  let uc = Hint.fold add_tuple ht_tuple uc in
  Hint.clear ht_tuple;
104 105
  uc

106
let add_pdecl_with_tuples ~wp uc pd = add_pdecl ~wp (flush_tuples uc) pd
107
let add_decl_with_tuples uc d = add_decl (flush_tuples uc) d
108

109 110 111
(** Namespace lookup *)

let uc_find_ls uc p =
112 113
  let ns = Theory.get_namespace (get_theory uc) in
  Typing.find_ns (fun ls -> ls.ls_name) Theory.ns_find_ls p ns
114

115
let get_id_ts = function
116
  | PT pt -> pt.its_ts.ts_name
117
  | TS ts -> ts.ts_name
Andrei Paskevich's avatar
Andrei Paskevich committed
118

119
let uc_find_ts uc p =
120
  Typing.find_ns get_id_ts ns_find_type_symbol p (get_namespace uc)
121 122 123 124 125 126 127

let get_id_ps = function
  | PV pv -> pv.pv_vs.vs_name
  | PS ps -> ps.ps_name
  | PL pl -> pl.pl_ls.ls_name
  | XS xs -> xs.xs_name
  | LS ls -> ls.ls_name
Andrei Paskevich's avatar
Andrei Paskevich committed
128

129
let uc_find_ps uc p =
130
  Typing.find_ns get_id_ps ns_find_prog_symbol p (get_namespace uc)
131

132 133
(** Typing type expressions *)

134
let rec dity_of_pty denv = function
135 136
  | Ptree.PPTtyvar (id, op) ->
      create_user_type_variable id op
137
  | Ptree.PPTtyapp (p, pl) ->
138
      let dl = List.map (dity_of_pty denv) pl in
139
      begin match uc_find_ts denv.uc p with
140
        | PT ts -> its_app ts dl
141
        | TS ts -> ts_app ts dl
142 143
      end
  | Ptree.PPTtuple pl ->
144
      let dl = List.map (dity_of_pty denv) pl in
145
      ts_app (ts_tuple (List.length pl)) dl
146

147 148 149
let opaque_binders acc args =
  List.fold_left (fun acc (_,_,dty) -> opaque_tvs acc dty) acc args

150 151
(** Typing program expressions *)

Andrei Paskevich's avatar
Andrei Paskevich committed
152
let dity_int  = ts_app ts_int  []
153
let dity_real = ts_app ts_real []
154
let dity_bool = ts_app ts_bool []
Andrei Paskevich's avatar
Andrei Paskevich committed
155
let dity_unit = ts_app ts_unit []
156

157
let unify_loc unify_fn loc x1 x2 = try unify_fn x1 x2 with
Andrei Paskevich's avatar
Andrei Paskevich committed
158
  | TypeMismatch (ity1,ity2,_) -> errorm ~loc
159
      "This expression has type %a,@ but is expected to have type %a"
160
      Mlw_pretty.print_ity ity2 Mlw_pretty.print_ity ity1
Andrei Paskevich's avatar
Andrei Paskevich committed
161 162 163
  | DTypeMismatch (dity1,dity2) -> errorm ~loc
      "This expression has type %a,@ but is expected to have type %a"
      Mlw_dty.print_dity dity2 Mlw_dty.print_dity dity1
164
  | exn when Debug.test_noflag Debug.stack_trace -> error ~loc exn
165

166 167 168 169 170 171 172
let expected_type { de_loc = loc ; de_type = (argl,res) } dity =
  if argl <> [] then errorm ~loc "This expression is not a first-order value";
  unify_loc unify loc dity res

let expected_type_weak { de_loc = loc ; de_type = (argl,res) } dity =
  if argl <> [] then errorm ~loc "This expression is not a first-order value";
  unify_loc unify_weak loc dity res
173

174
let rec extract_labels labs loc e = match e.Ptree.expr_desc with
175
  | Ptree.Enamed (Ptree.Lstr s, e) -> extract_labels (Slab.add s labs) loc e
176 177 178 179
  | Ptree.Enamed (Ptree.Lpos p, e) -> extract_labels labs (Some p) e
  | Ptree.Ecast  (e, ty) ->
      let labs, loc, d = extract_labels labs loc e in
      labs, loc, Ptree.Ecast ({ e with Ptree.expr_desc = d }, ty)
180
  | e -> labs, loc, e
181

182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206
(* Hack alert. Since the result type in "let [rec] fn x y : ty = ..."
   is moved to Ecast and then usually lost in destructive unification,
   we try to preserve opacity annotations by moving them to binders. *)
let pass_opacity (e,_) bl =
  let rec find e = match e.Ptree.expr_desc with
    | Ptree.Ecast (_, pty) -> Some pty
    | Ptree.Enamed (_, e) -> find e
    | _ -> None in
  match find e with
  | Some pty ->
      let ht = Hstr.create 3 in
      let rec fill = function
        | Ptree.PPTtyapp (_, pl) | Ptree.PPTtuple pl -> List.iter fill pl
        | Ptree.PPTtyvar (id, true) -> Hstr.replace ht id.id ()
        | Ptree.PPTtyvar _ -> () in
      fill pty;
      if Hstr.length ht = 0 then bl else
      let rec pass = function
        | Ptree.PPTtyvar (id,op) -> Ptree.PPTtyvar (id, op || Hstr.mem ht id.id)
        | Ptree.PPTtyapp (p, pl) -> Ptree.PPTtyapp (p, List.map pass pl)
        | Ptree.PPTtuple pl -> Ptree.PPTtuple (List.map pass pl) in
      List.map (fun (loc,id,gh,pty) -> loc, id, gh, Opt.map pass pty) bl
  | None ->
      bl

207 208 209
let rec decompose_app args e = match e.Ptree.expr_desc with
  | Eapply (e1, e2) -> decompose_app (e2 :: args) e1
  | _ -> e, args
210

211 212 213 214 215 216 217
(* record parsing *)

let parse_record uc fll =
  let pl = match fll with
    | [] -> raise EmptyRecord
    | (pl,_)::_ -> pl in
  let its = match pl.pl_args with
218
    | [{ fd_ity = { ity_node = Ityapp (its,_,_) }}] -> its
219 220
    | _ -> raise (BadRecordField pl.pl_ls) in
  let cs, pjl = match find_constructors (get_known uc) its with
221
    | [cs,pjl] -> cs, List.map (Opt.get_exn (BadRecordField pl.pl_ls)) pjl
222 223 224 225 226 227 228 229 230
    | _ -> raise (BadRecordField pl.pl_ls) in
  let pjs = List.fold_left (fun s pj -> Sls.add pj.pl_ls s) Sls.empty pjl in
  let flm = List.fold_left (fun m (pj,v) -> let pj = pj.pl_ls in
    if not (Sls.mem pj pjs) then raise (BadRecordField pj) else
      Mls.add_new (DuplicateRecordField (cs.pl_ls,pj)) pj v m)
    Mls.empty fll
  in
  cs,pjl,flm

231 232
let find_prog_field uc (p,e) = match uc_find_ps uc p with PL pl -> pl, e
  | _ -> errorm ~loc:(qloc p) "'%a' is not a record field" print_qualid p
233

234
let find_pure_field uc (p,e) = uc_find_ls uc p, e
235

236 237
let is_pure_record uc = function
  | fl :: _ -> (try ignore (find_prog_field uc fl); false with _ -> true)
238
  | [] -> raise Decl.EmptyRecord
239 240

let hidden_pl ~loc pl =
241 242
  { de_desc = DEglobal_pl pl;
    de_type = specialize_plsymbol pl;
243
    de_loc  = loc; de_lab = Slab.empty }
244 245

let hidden_ls ~loc ls =
246
  { de_desc = DEglobal_ls ls;
247
    de_type = Loc.try1 loc specialize_lsymbol ls;
248
    de_loc  = loc; de_lab = Slab.empty }
249 250

(* helper functions for let-expansion *)
251
let test_var e = match e.de_desc with
252
  | DElocal _ | DEglobal_pv _ | DEconstant _ -> true
253 254
  | _ -> false

255
let mk_var name e =
256
  if test_var e then e else
257
  { de_desc = DElocal name;
258 259
    de_type = e.de_type;
    de_loc  = e.de_loc;
260
    de_lab  = Slab.empty }
261

262 263 264
let mk_id s loc =
  { id = s; id_loc = loc; id_lab = [] }

265 266
let mk_dexpr desc dvty loc labs =
  { de_desc = desc; de_type = dvty; de_loc = loc; de_lab = labs }
267

268
let mk_let name ~loc ~uloc e (desc,dvty) =
269
  if test_var e then desc, dvty else
270
  let loc = Opt.get_def loc uloc in
271
  let e1 = mk_dexpr desc dvty loc Slab.empty in
272
  DElet (mk_id name e.de_loc, false, e, e1), dvty
273

274 275
(* patterns *)

276 277 278 279 280 281 282 283 284
let add_poly id dvty denv =
  let locals = Mstr.add id.id (Some denv.tvars, dvty) denv.locals in
  { denv with locals = locals }

let add_mono id dvty denv =
  let locals = Mstr.add id.id (None, dvty) denv.locals in
  { denv with locals = locals; tvars = add_dvty denv.tvars dvty }

let add_var id dity denv = add_mono id ([],dity) denv
285

286
let specialize_qualid uc p = match uc_find_ps uc p with
287
  | PV pv -> DEglobal_pv pv, ([],specialize_pvsymbol pv)
288 289
  | PS ps -> DEglobal_ps ps, specialize_psymbol  ps
  | PL pl -> DEglobal_pl pl, specialize_plsymbol pl
290
  | LS ls -> DEglobal_ls ls, Loc.try1 (qloc p) specialize_lsymbol ls
291
  | XS xs -> errorm ~loc:(qloc p) "unexpected exception symbol %a" print_xs xs
292

293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311
let chainable_qualid uc p = match uc_find_ps uc p with
  | PS { ps_aty = { aty_args = [pv1;pv2]; aty_result = VTvalue ity }}
  | PS { ps_aty = { aty_args = [pv1]; aty_result =
          VTarrow { aty_args = [pv2]; aty_result = VTvalue ity }}} ->
      ity_equal ity ity_bool
      && not (ity_equal pv1.pv_ity ity_bool)
      && not (ity_equal pv2.pv_ity ity_bool)
  | LS { ls_args = [ty1;ty2]; ls_value = ty } ->
      Opt.fold (fun _ ty -> ty_equal ty ty_bool) true ty
      && not (ty_equal ty1 ty_bool)
      && not (ty_equal ty2 ty_bool)
  | PS _ | LS _ | PL _ | PV _ | XS _ -> false

let chainable_op denv op =
  op.id = "infix =" || op.id = "infix <>" ||
  match Mstr.find_opt op.id denv.locals with
  | Some (_, dvty) -> is_chainable dvty
  | None -> chainable_qualid denv.uc (Qident op)

312 313
let find_xsymbol uc p = match uc_find_ps uc p with
  | XS xs -> xs
314
  | _ -> errorm ~loc:(qloc p) "exception symbol expected"
Andrei Paskevich's avatar
Andrei Paskevich committed
315

316
let find_variant_ls uc p = match uc_find_ls uc p with
317 318
  | { ls_args = [u;v]; ls_value = None } as ls when ty_equal u v -> ls
  | ls -> errorm ~loc:(qloc p) "%a is not a binary relation" Pretty.print_ls ls
319

320
let find_global_vs uc p = try match uc_find_ps uc p with
321 322
  | PV pv -> Some pv.pv_vs
  | _ -> None
323
  with _ -> None
324

325 326 327 328 329 330
let find_vs uc lvm p = match p with
  | Qdot _ -> find_global_vs uc p
  | Qident id ->
      let ovs = Mstr.find_opt id.id lvm in
      if ovs = None then find_global_vs uc p else ovs

331
let rec dpattern denv ({ pat_loc = loc } as pp) dity = match pp.pat_desc with
332
  | Ptree.PPpwild ->
333
      PPwild, denv
334
  | Ptree.PPpvar id ->
335
      PPvar (Denv.create_user_id id), add_var id dity denv
336
  | Ptree.PPpapp (q,ppl) ->
337
      let sym, dvty = specialize_qualid denv.uc q in
338
      dpat_app denv loc (mk_dexpr sym dvty loc Slab.empty) ppl dity
339
  | Ptree.PPprec fl when is_pure_record denv.uc fl ->
340
      let kn = Theory.get_known (get_theory denv.uc) in
341
      let fl = List.map (find_pure_field denv.uc) fl in
342 343 344
      let cs,pjl,flm = Loc.try2 loc Decl.parse_record kn fl in
      let wild = { pat_desc = Ptree.PPpwild; pat_loc = loc } in
      let get_val pj = Mls.find_def wild pj flm in
345
      dpat_app denv loc (hidden_ls ~loc cs) (List.map get_val pjl) dity
346
  | Ptree.PPprec fl ->
347
      let fl = List.map (find_prog_field denv.uc) fl in
348 349 350
      let cs,pjl,flm = Loc.try2 loc parse_record denv.uc fl in
      let wild = { pat_desc = Ptree.PPpwild; pat_loc = loc } in
      let get_val pj = Mls.find_def wild pj.pl_ls flm in
351
      dpat_app denv loc (hidden_pl ~loc cs) (List.map get_val pjl) dity
352 353
  | Ptree.PPptuple ppl ->
      let cs = fs_tuple (List.length ppl) in
354
      dpat_app denv loc (hidden_ls ~loc cs) ppl dity
355
  | Ptree.PPpor (lpp1, lpp2) ->
356 357 358
      let pp1, denv = dpattern denv lpp1 dity in
      let pp2, denv = dpattern denv lpp2 dity in
      PPor (pp1, pp2), denv
359
  | Ptree.PPpas (pp, id) ->
360 361 362 363 364 365 366
      let pp, denv = dpattern denv pp dity in
      PPas (pp, Denv.create_user_id id), add_var id dity denv

and dpat_app denv gloc ({ de_loc = loc } as de) ppl dity =
  let ls = match de.de_desc with
    | DEglobal_pl pl -> pl.pl_ls
    | DEglobal_ls ls -> ls
367 368
    | DEglobal_pv pv -> errorm ~loc "%a is not a constructor" print_pv pv
    | DEglobal_ps ps -> errorm ~loc "%a is not a constructor" print_ps ps
369
    | _ -> assert false in
370
  let argl, res = de.de_type in
371 372
  if List.length argl <> List.length ppl then
    error ~loc:gloc (Term.BadArity (ls, List.length ppl));
373 374 375 376 377 378 379 380 381
  unify_loc unify gloc res dity;
  let add_pp lp ty (ppl, denv) =
    let pp, denv = dpattern denv lp ty in pp::ppl, denv in
  let ppl, denv = List.fold_right2 add_pp ppl argl ([],denv) in
  let pp = match de.de_desc with
    | DEglobal_pl pl -> Mlw_expr.PPpapp (pl, ppl)
    | DEglobal_ls ls -> Mlw_expr.PPlapp (ls, ppl)
    | _ -> assert false in
  pp, denv
382

383 384
(* specifications *)

385
let dbinders denv bl =
386 387
  let s = ref Sstr.empty in
  let dbinder (loc,id,gh,pty) (denv,bl,tyl) =
388
    let dity = match pty with
389
      | Some pty -> dity_of_pty denv pty
390 391 392 393 394 395 396 397 398 399
      | None -> create_type_variable ()
    in
    let denv, id = match id with
      | Some ({ id = x; id_loc = loc } as id) ->
          s := Loc.try3 loc Sstr.add_new (DuplicateProgVar x) x !s;
          add_var id dity denv, id
      | None ->
          denv, { id = "_"; id_loc = loc; id_lab = [] }
    in
    denv, (id,gh,dity)::bl, dity::tyl
400 401
  in
  List.fold_right dbinder bl (denv,[],[])
402

403
let mk_dpost loc = function
404
  | [{ pat_desc = PPpwild | PPptuple [] | PPpvar _ }, _ as p] -> p
405
  | l ->
406 407 408 409
      let i = { id = "(null)"; id_loc = loc; id_lab = [] } in
      let p = { pat_desc = Ptree.PPpvar i; pat_loc = loc } in
      let v = { pp_desc = Ptree.PPvar (Qident i); pp_loc = loc } in
      p, { pp_desc = PPmatch (v,l); pp_loc = loc }
410 411

let dpost ql = List.map (fun (loc, ql) -> mk_dpost loc ql) ql
412 413

let dxpost uc ql =
414
  let add_exn (q,pat,f) m =
415
    let xs = find_xsymbol uc q in
416 417 418 419 420 421
    Mexn.change (function
      | Some l -> Some ((pat,f) :: l)
      | None   -> Some ((pat,f) :: [])) xs m in
  let exn_map (loc,ql) =
    let m = List.fold_right add_exn ql Mexn.empty in
    Mexn.map (fun ql -> [mk_dpost loc ql]) m in
422 423 424
  let add_map ql m =
    Mexn.union (fun _ l r -> Some (l @ r)) (exn_map ql) m in
  List.fold_right add_map ql Mexn.empty
425 426

let dvariant uc var =
427
  List.map (fun (le,q) -> le, Opt.map (find_variant_ls uc) q) var
428 429 430

let dspec uc sp = {
  ds_pre     = sp.sp_pre;
431
  ds_post    = dpost sp.sp_post;
432
  ds_xpost   = dxpost uc sp.sp_xpost;
433
  ds_writes  = sp.sp_writes;
434 435
  ds_variant = dvariant uc sp.sp_variant;
}
436

437 438 439
let rec dtype_c denv (tyv, sp) =
  let tyv, dvty = dtype_v denv tyv in
  (tyv, dspec denv.uc sp), dvty
440 441 442

and dtype_v denv = function
  | Tpure pty ->
443
      let dity = dity_of_pty denv pty in
444
      DSpecV dity, ([],dity)
445
  | Tarrow (bl,tyc) ->
446
      let bl = List.map (fun (l,i,g,t) -> l,i,g,Some t) bl in
447
      let denv,bl,tyl = dbinders denv bl in
448 449
      let tyc,(argl,res) = dtype_c denv tyc in
      DSpecA (bl,tyc), (tyl @ argl,res)
450

451
(* expressions *)
452

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
453 454 455 456 457 458 459
let add_lemma_label ~top id = function
  | Gnone -> id, false
  | Gghost -> id, true
  | Glemma when not top ->
      errorm ~loc:id.id_loc "lemma functions are only allowed at toplevel"
  | Glemma -> { id with id_lab = Lstr Mlw_wp.lemma_label :: id.id_lab }, true

460
let de_unit ~loc = hidden_ls ~loc Mlw_expr.fs_void
461

462 463 464 465 466 467 468 469 470 471 472 473 474 475
let de_app _loc e el =
  let argl, res = e.de_type in
  let rec unify_list argl el = match argl, el with
    | arg::argl, e::el when Loc.equal e.de_loc Loc.dummy_position ->
        expected_type e arg; unify_list argl el
    | arg::argl, e::el ->
        let res = unify_list argl el in expected_type e arg; res
    | argl, [] -> argl, res
    | [], _ when fst e.de_type = [] -> errorm ~loc:e.de_loc
        "This expression is not a function and cannot be applied"
    | [], _ -> errorm ~loc:e.de_loc
        "This function is applied to too many arguments"
  in
  DEapply (e, el), unify_list argl el
476

Andrei Paskevich's avatar
Andrei Paskevich committed
477
let rec dexpr denv e =
478
  let loc = e.Ptree.expr_loc in
479
  let labs, uloc, d = extract_labels Slab.empty denv.uloc e in
Andrei Paskevich's avatar
Andrei Paskevich committed
480
  let denv = { denv with uloc = uloc } in
481
  let d, ty = de_desc denv loc d in
482
  let loc = Opt.get_def loc uloc in
483
  mk_dexpr d ty loc labs
484

485
and de_desc denv loc = function
486 487 488 489 490 491
  | Ptree.Eident (Qident {id = x} as p) ->
      begin match Mstr.find_opt x denv.locals with
        | Some (Some tvs, dvty) -> DElocal x, specialize_scheme tvs dvty
        | Some (None,     dvty) -> DElocal x, dvty
        | None                  -> specialize_qualid denv.uc p
      end
492
  | Ptree.Eident p ->
493
      specialize_qualid denv.uc p
494 495
  | Ptree.Eapply (e1, e2) ->
      let e, el = decompose_app [e2] e1 in
Andrei Paskevich's avatar
Andrei Paskevich committed
496
      let el = List.map (dexpr denv) el in
497
      de_app loc (dexpr denv e) el
498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528
  | Ptree.Einfix (e12, op2, e3)
  | Ptree.Einnfix (e12, op2, e3) ->
      let mk_bool (d,ty) =
        let de = mk_dexpr d ty (Opt.get_def loc denv.uloc) Slab.empty in
        expected_type de dity_bool; de in
      let make_app de1 op de2 =
        let id = Ptree.Eident (Qident op) in
        let e0 = { expr_desc = id; expr_loc = op.id_loc } in
        de_app loc (dexpr denv e0) [de1; de2] in
      let make_app de1 op de2 =
        if op.id <> "infix <>" then make_app de1 op de2 else
          let de12 = mk_bool (make_app de1 { op with id = "infix =" } de2) in
          DEnot de12, de12.de_type in
      let rec make_chain n1 n2 de1 = function
        | [op,de2] ->
            make_app de1 op de2
        | (op,de2) :: ch ->
            let v = mk_var n1 de2 in
            let de12 = mk_bool (make_app de1 op v) in
            let de23 = mk_bool (make_chain n2 n1 v ch) in
            let d = DElazy (LazyAnd, de12, de23) in
            mk_let n1 ~loc ~uloc:denv.uloc de2 (d, de12.de_type)
        | [] -> assert false in
      let rec get_chain e12 acc = match e12.expr_desc with
        | Ptree.Einfix (e1, op1, e2) when chainable_op denv op1 ->
            get_chain e1 ((op1, dexpr denv e2) :: acc)
        | _ -> e12, acc in
      let e1, ch = if chainable_op denv op2
        then get_chain e12 [op2, dexpr denv e3]
        else e12, [op2, dexpr denv e3] in
      make_chain "q1 " "q2 " (dexpr denv e1) ch
529
  | Ptree.Elet (id, gh, e1, e2) ->
Andrei Paskevich's avatar
Andrei Paskevich committed
530
      let e1 = dexpr denv e1 in
531 532 533
      let denv = match e1.de_desc with
        | DEfun _ -> add_poly id e1.de_type denv
        | _       -> add_mono id e1.de_type denv in
Andrei Paskevich's avatar
Andrei Paskevich committed
534
      let e2 = dexpr denv e2 in
535
      DElet (id, gh, e1, e2), e2.de_type
536
  | Ptree.Eletrec (fdl, e1) ->
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
537
      let fdl = dletrec ~top:false denv fdl in
538
      let add_one denv (id,_,dvty,_,_) = add_poly id dvty denv in
539
      let denv = List.fold_left add_one denv fdl in
Andrei Paskevich's avatar
Andrei Paskevich committed
540
      let e1 = dexpr denv e1 in
541
      DEletrec (fdl, e1), e1.de_type
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
542
  | Ptree.Efun (bl, tr) ->
543
      let denv, bl, tyl = dbinders denv (pass_opacity tr bl) in
544
      let tr, (argl, res) = dtriple denv tr in
545
      DEfun (bl, tr), (tyl @ argl, res)
546
  | Ptree.Ecast (e1, pty) ->
Andrei Paskevich's avatar
Andrei Paskevich committed
547
      let e1 = dexpr denv e1 in
548
      expected_type_weak e1 (dity_of_pty denv pty);
549
      e1.de_desc, e1.de_type
550 551
  | Ptree.Enamed _ ->
      assert false
552
  | Ptree.Esequence (e1, e2) ->
Andrei Paskevich's avatar
Andrei Paskevich committed
553
      let e1 = dexpr denv e1 in
554
      expected_type e1 dity_unit;
Andrei Paskevich's avatar
Andrei Paskevich committed
555
      let e2 = dexpr denv e2 in
556
      DElet (mk_id "_" loc, false, e1, e2), e2.de_type
557
  | Ptree.Eif (e1, e2, e3) ->
Andrei Paskevich's avatar
Andrei Paskevich committed
558
      let e1 = dexpr denv e1 in
559
      expected_type e1 dity_bool;
Andrei Paskevich's avatar
Andrei Paskevich committed
560 561
      let e2 = dexpr denv e2 in
      let e3 = dexpr denv e3 in
562 563 564
      let res = create_type_variable () in
      expected_type e2 res;
      expected_type e3 res;
565
      DEif (e1, e2, e3), e2.de_type
566 567
  | Ptree.Etuple el ->
      let ls = fs_tuple (List.length el) in
Andrei Paskevich's avatar
Andrei Paskevich committed
568
      let el = List.map (dexpr denv) el in
569
      de_app loc (hidden_ls ~loc ls) el
570
  | Ptree.Erecord fl when is_pure_record denv.uc fl ->
571
      let kn = Theory.get_known (get_theory denv.uc) in
572
      let fl = List.map (find_pure_field denv.uc) fl in
573 574
      let cs,pjl,flm = Loc.try2 loc Decl.parse_record kn fl in
      let get_val pj = match Mls.find_opt pj flm with
Andrei Paskevich's avatar
Andrei Paskevich committed
575
        | Some e -> dexpr denv e
576
        | None -> error ~loc (Decl.RecordFieldMissing (cs,pj)) in
577
      de_app loc (hidden_ls ~loc cs) (List.map get_val pjl)
578
  | Ptree.Erecord fl ->
579
      let fl = List.map (find_prog_field denv.uc) fl in
580 581
      let cs,pjl,flm = Loc.try2 loc parse_record denv.uc fl in
      let get_val pj = match Mls.find_opt pj.pl_ls flm with
Andrei Paskevich's avatar
Andrei Paskevich committed
582
        | Some e -> dexpr denv e
583
        | None -> error ~loc (Decl.RecordFieldMissing (cs.pl_ls,pj.pl_ls)) in
584
      de_app loc (hidden_pl ~loc cs) (List.map get_val pjl)
585
  | Ptree.Eupdate (e1, fl) when is_pure_record denv.uc fl ->
Andrei Paskevich's avatar
Andrei Paskevich committed
586
      let e1 = dexpr denv e1 in
587
      let e0 = mk_var "q " e1 in
588
      let kn = Theory.get_known (get_theory denv.uc) in
589
      let fl = List.map (find_pure_field denv.uc) fl in
590 591
      let cs,pjl,flm = Loc.try2 loc Decl.parse_record kn fl in
      let get_val pj = match Mls.find_opt pj flm with
Andrei Paskevich's avatar
Andrei Paskevich committed
592
        | Some e -> dexpr denv e
593
        | None ->
594
            let loc = Loc.dummy_position in
595 596
            let d, dvty = de_app loc (hidden_ls ~loc pj) [e0] in
            mk_dexpr d dvty loc Slab.empty in
597
      let res = de_app loc (hidden_ls ~loc cs) (List.map get_val pjl) in
598
      mk_let "q " ~loc ~uloc:denv.uloc e1 res
599
  | Ptree.Eupdate (e1, fl) ->
Andrei Paskevich's avatar
Andrei Paskevich committed
600
      let e1 = dexpr denv e1 in
601
      let e0 = mk_var "q " e1 in
602
      let fl = List.map (find_prog_field denv.uc) fl in
603 604
      let cs,pjl,flm = Loc.try2 loc parse_record denv.uc fl in
      let get_val pj = match Mls.find_opt pj.pl_ls flm with
Andrei Paskevich's avatar
Andrei Paskevich committed
605
        | Some e -> dexpr denv e
606
        | None ->
607
            let loc = Loc.dummy_position in
608 609
            let d, dvty = de_app loc (hidden_pl ~loc pj) [e0] in
            mk_dexpr d dvty loc Slab.empty in
610
      let res = de_app loc (hidden_pl ~loc cs) (List.map get_val pjl) in
611
      mk_let "q " ~loc ~uloc:denv.uloc e1 res
Andrei Paskevich's avatar
Andrei Paskevich committed
612
  | Ptree.Eassign (e1, q, e2) ->
613 614 615 616 617
      let fl = dexpr denv { expr_desc = Eident q; expr_loc = qloc q } in
      let pl = match fl.de_desc with
        | DEglobal_pl pl -> pl
        | _ -> Loc.errorm ~loc:(qloc q) "%a is not a field name" print_qualid q
      in
Andrei Paskevich's avatar
Andrei Paskevich committed
618 619
      let e1 = dexpr denv e1 in
      let e2 = dexpr denv e2 in
620 621
      let d, ty = de_app loc fl [e1] in
      let e0 = mk_dexpr d ty loc Slab.empty in
622
      let res = create_type_variable () in
623
      expected_type e0 res;
624
      expected_type_weak e2 res;
625
      DEassign (pl, e1, e2), ([], dity_unit)
626
  | Ptree.Econstant (Number.ConstInt _ as c) ->
627
      DEconstant c, ([], dity_int)
628
  | Ptree.Econstant (Number.ConstReal _ as c) ->
629
      DEconstant c, ([], dity_real)
630
  | Ptree.Enot e1 ->
Andrei Paskevich's avatar
Andrei Paskevich committed
631
      let e1 = dexpr denv e1 in
632
      expected_type e1 dity_bool;
633
      DEnot e1, ([], dity_bool)
634
  | Ptree.Elazy (op, e1, e2) ->
Andrei Paskevich's avatar
Andrei Paskevich committed
635 636
      let e1 = dexpr denv e1 in
      let e2 = dexpr denv e2 in
637 638
      expected_type e1 dity_bool;
      expected_type e2 dity_bool;
639
      DElazy (op, e1, e2), ([], dity_bool)
640
  | Ptree.Ematch (e1, bl) ->
Andrei Paskevich's avatar
Andrei Paskevich committed
641
      let e1 = dexpr denv e1 in
642
      let ety = create_type_variable () in
643
      let res = create_type_variable () in
644
      expected_type e1 ety;
645
      let branch (pp,e) =
646
        let ppat, denv = dpattern denv pp ety in
Andrei Paskevich's avatar
Andrei Paskevich committed
647
        let e = dexpr denv e in
648 649
        expected_type e res;
        ppat, e in
650
      DEmatch (e1, List.map branch bl), ([], res)
Andrei Paskevich's avatar
Andrei Paskevich committed
651
  | Ptree.Eraise (q, e1) ->
652
      let xs = find_xsymbol denv.uc q in
Andrei Paskevich's avatar
Andrei Paskevich committed
653
      let e1 = match e1 with
Andrei Paskevich's avatar
Andrei Paskevich committed
654
        | Some e1 -> dexpr denv e1
655
        | None when ity_equal xs.xs_ity ity_unit -> de_unit ~loc
Andrei Paskevich's avatar
Andrei Paskevich committed
656
        | _ -> errorm ~loc "exception argument expected" in
Andrei Paskevich's avatar
minor  
Andrei Paskevich committed
657
      expected_type e1 (specialize_xsymbol xs);
658
      DEraise (xs, e1), ([], create_type_variable ())
Andrei Paskevich's avatar
Andrei Paskevich committed
659
  | Ptree.Etry (e1, cl) ->
660
      let res = create_type_variable () in
Andrei Paskevich's avatar
Andrei Paskevich committed
661
      let e1 = dexpr denv e1 in
662
      expected_type e1 res;
663
      let branch (q, pp, e) =
664
        let xs = find_xsymbol denv.uc q in
665
        let ety = specialize_xsymbol xs in
666
        let ppat, denv = dpattern denv pp ety in
667
        let e = dexpr denv e in
668
        expected_type e res;
669
        xs, ppat, e in
Andrei Paskevich's avatar
minor  
Andrei Paskevich committed
670
      DEtry (e1, List.map branch cl), e1.de_type
671
  | Ptree.Eabsurd ->
672
      DEabsurd, ([], create_type_variable ())
673
  | Ptree.Eassert (ak, lexpr) ->
674
      DEassert (ak, lexpr), ([], dity_unit)
Andrei Paskevich's avatar
Andrei Paskevich committed
675 676
  | Ptree.Emark (id, e1) ->
      let e1 = dexpr denv e1 in
677
      DEmark (id, e1), e1.de_type
678
  | Ptree.Eany tyc ->
679 680
      let tyc, dvty = dtype_c denv tyc in
      DEany tyc, dvty
681 682 683
  | Ptree.Eghost e1 ->
      let e1 = dexpr denv e1 in
      DEghost e1, e1.de_type
684
  | Ptree.Eabstract (e1, sp) ->
685
      let e1 = dexpr denv e1 in
686 687
      let sp = dspec denv.uc sp in
      DEabstract (e1, sp), e1.de_type
688 689 690 691
  | Ptree.Eloop ({ loop_invariant = inv; loop_variant = var }, e1) ->
      let e1 = dexpr denv e1 in
      let var = dvariant denv.uc var in
      expected_type e1 dity_unit;
Andrei Paskevich's avatar
minor  
Andrei Paskevich committed
692
      DEloop (var, inv, e1), e1.de_type
693 694 695 696 697 698 699 700
  | Ptree.Efor (id, efrom, dir, eto, inv, e1) ->
      let efrom = dexpr denv efrom in
      let eto = dexpr denv eto in
      let denv = add_var id dity_int denv in
      let e1 = dexpr denv e1 in
      expected_type efrom dity_int;
      expected_type eto dity_int;
      expected_type e1 dity_unit;
Andrei Paskevich's avatar
minor  
Andrei Paskevich committed
701
      DEfor (id, efrom, dir, eto, inv, e1), e1.de_type
702

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
703
and dletrec ~top denv fdl =
704
  (* add all functions into the environment *)
705
  let add_one denv (_,id,_,bl,_) =
706 707
    let argl = List.map (fun _ -> create_type_variable ()) bl in
    let dvty = argl, create_type_variable () in
708
    add_mono id dvty denv, dvty in
709
  let denv, dvtyl = Lists.map_fold_left add_one denv fdl in
710
  (* then unify the binders *)
711 712
  let bind_one (_,_,_,bl,tr) (argl,res) =
    let denv,bl,tyl = dbinders denv (pass_opacity tr bl) in
713 714
    List.iter2 unify argl tyl;
    denv,bl,tyl,res in
715
  let denvl = List.map2 bind_one fdl dvtyl in
716
  (* then type-check the bodies *)
717
  let type_one (loc,id,gh,_,tr) (denv,bl,tyl,tyv) =
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed