typing.ml 26.6 KB
Newer Older
1 2
(**************************************************************************)
(*                                                                        *)
Jean-Christophe Filliâtre's avatar
headers  
Jean-Christophe Filliâtre committed
3 4 5 6 7
(*  Copyright (C) 2010-                                                   *)
(*    Francois Bobot                                                      *)
(*    Jean-Christophe Filliatre                                           *)
(*    Johannes Kanig                                                      *)
(*    Andrei Paskevich                                                    *)
8 9 10 11 12 13 14 15 16 17 18
(*                                                                        *)
(*  This software is free software; you can redistribute it and/or        *)
(*  modify it under the terms of the GNU Library General Public           *)
(*  License version 2.1, with the special exception on linking            *)
(*  described in file LICENSE.                                            *)
(*                                                                        *)
(*  This software is distributed in the hope that it will be useful,      *)
(*  but WITHOUT ANY WARRANTY; without even the implied warranty of        *)
(*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.                  *)
(*                                                                        *)
(**************************************************************************)
19

20 21
open Util
open Format
22
open Pp
23
open Ident
24
open Ty
25
open Term
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
26
open Ptree
27
open Theory
28

29 30 31
(** errors *)

type error = 
32
  | Message of string
33
  | ClashType of string
34
  | DuplicateTypeVar of string
35
  | UnboundType of string
36
  | TypeArity of qualid * int * int
37
  | Clash of string
38 39
  | PredicateExpected
  | TermExpected
40
  | UnboundSymbol of string
41 42
  | TermExpectedType of (formatter -> unit) * (formatter -> unit) 
      (* actual / expected *)
43
  | BadNumberOfArguments of Ident.ident * int * int 
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
44
  | ClashTheory of string
45
  | ClashNamespace of string
46
  | UnboundTheory of string
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
47
  | AlreadyTheory of string
48
  | UnboundNamespace of string
49 50 51 52
  | UnboundFile of string
  | UnboundDir of string
  | AmbiguousPath of string * string
  | NotInLoadpath of string
53 54
  | CyclicTypeDef
  | UnboundTypeVar of string
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
55
  | AnyMessage of string
56 57 58 59 60 61 62

exception Error of error

let error ?loc e = match loc with
  | None -> raise (Error e)
  | Some loc -> raise (Loc.Located (loc, Error e))

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
63 64 65 66 67 68 69 70 71 72 73
let errorm ?loc f =
  let buf = Buffer.create 512 in
  let fmt = Format.formatter_of_buffer buf in
  Format.kfprintf 
    (fun _ -> 
       Format.pp_print_flush fmt ();
       let s = Buffer.contents buf in
       Buffer.clear buf;
       error ?loc (AnyMessage s))
    fmt f

74
let rec print_qualid fmt = function
75
  | Qident s -> fprintf fmt "%s" s.id
76
  | Qdot (m, s) -> fprintf fmt "%a.%s" print_qualid m s.id
77

78
let report fmt = function
79 80
  | Message s ->
      fprintf fmt "%s" s
81 82
  | ClashType s ->
      fprintf fmt "clash with previous type %s" s
83
  | DuplicateTypeVar s ->
84
      fprintf fmt "duplicate type parameter %s" s
85
  | UnboundType s ->
86
       fprintf fmt "Unbound type '%s'" s
87
  | TypeArity (id, a, n) ->
88
      fprintf fmt "@[The type %a expects %d argument(s),@ " print_qualid id a;
89 90
      fprintf fmt "but is applied to %d argument(s)@]" n
  | Clash id ->
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
91
      fprintf fmt "Clash with previous symbol %s" id
92 93 94 95
  | PredicateExpected ->
      fprintf fmt "syntax error: predicate expected"
  | TermExpected ->
      fprintf fmt "syntax error: term expected"
96
  | UnboundSymbol s ->
97
       fprintf fmt "Unbound symbol '%s'" s
98
  | BadNumberOfArguments (s, n, m) ->
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
99
      fprintf fmt "@[Symbol `%s' is applied to %d terms,@ " s.id_short n;
100 101 102 103
      fprintf fmt "but is expecting %d arguments@]" m
  | TermExpectedType (ty1, ty2) ->
      fprintf fmt "@[This term has type "; ty1 fmt; 
      fprintf fmt "@ but is expected to have type@ "; ty2 fmt; fprintf fmt "@]"
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
104 105
  | ClashTheory s ->
      fprintf fmt "clash with previous theory %s" s
106 107
  | ClashNamespace s ->
      fprintf fmt "clash with previous namespace %s" s
108 109
  | UnboundTheory s ->
      fprintf fmt "unbound theory %s" s
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
110 111
  | AlreadyTheory s ->
      fprintf fmt "already using a theory with name %s" s
112 113
  | UnboundNamespace s ->
      fprintf fmt "unbound namespace %s" s
114 115 116 117 118 119 120 121
  | UnboundFile s ->
      fprintf fmt "no such file %s" s
  | UnboundDir s ->
      fprintf fmt "no such directory %s" s
  | AmbiguousPath (f1, f2) ->
      fprintf fmt "@[ambiguous path:@ both `%s'@ and `%s'@ match@]" f1 f2
  | NotInLoadpath f ->
      fprintf fmt "cannot find `%s' in loadpath" f
122 123 124 125
  | CyclicTypeDef ->
      fprintf fmt "cyclic type definition"
  | UnboundTypeVar s ->
      fprintf fmt "unbound type variable '%s" s
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
126 127
  | AnyMessage s ->
      fprintf fmt "%s" s
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
128

129 130
(** Environments *)

131
module S = Set.Make(String)
132 133 134 135
module M = Map.Make(String)

type env = {
  loadpath : string list;
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
136
  theories : theory M.t; (* local theories *)
137 138 139 140 141 142
}

let create lp = {
  loadpath = lp;
  theories = M.empty;
}
143 144

(** typing using destructive type variables 
145

146 147 148 149 150 151
    parsed trees        intermediate trees       typed trees
      (Ptree)               (D below)               (Term)
   -----------------------------------------------------------
     ppure_type  ---dty--->   dty       ---ty--->    ty
      lexpr      --dterm-->   dterm     --term-->    term
      lexpr      --dfmla-->   dfmla     --fmla-->    fmla
152

153 154 155 156 157 158 159 160 161 162 163 164 165
*)

(** types with destructive type variables *)

type dty =
  | Tyvar of type_var
  | Tyapp of tysymbol * dty list
      
and type_var = { 
  tag : int; 
  user : bool;
  tvsymbol : tvsymbol;
  mutable type_val : dty option;
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
166
  type_var_loc : loc option;
167
}
168

169 170 171 172
let rec print_dty fmt = function
  | Tyvar { type_val = Some t } ->
      print_dty fmt t
  | Tyvar { type_val = None; tvsymbol = v } ->
173
      fprintf fmt "'%s" v.id_short
174
  | Tyapp (s, []) ->
175
      fprintf fmt "%s" s.ts_name.id_short
176
  | Tyapp (s, [t]) -> 
177
      fprintf fmt "%a %s" print_dty t s.ts_name.id_short
178
  | Tyapp (s, l) -> 
179 180
      fprintf fmt "(%a) %s" 
	(print_list comma print_dty) l s.ts_name.id_short
181

182 183
let create_type_var =
  let t = ref 0 in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
184
  fun ?loc ~user tv -> 
185
    incr t; 
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
186 187
    { tag = !t; user = user; tvsymbol = tv; type_val = None;
      type_var_loc = loc }
188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215

let rec occurs v = function
  | Tyvar { type_val = Some t } -> occurs v t
  | Tyvar { tag = t; type_val = None } -> v.tag = t
  | Tyapp (_, l) -> List.exists (occurs v) l

(* destructive type unification *)
let rec unify t1 t2 = match t1, t2 with
  | Tyvar { type_val = Some t1 }, _ ->
      unify t1 t2
  | _, Tyvar { type_val = Some t2 } ->
      unify t1 t2
  | Tyvar v1, Tyvar v2 when v1.tag = v2.tag ->
      true
	(* instantiable variables *)
  | Tyvar ({user=false} as v), t
  | t, Tyvar ({user=false} as v) ->
      not (occurs v t) && (v.type_val <- Some t; true)
	(* recursive types *)
  | Tyapp (s1, l1), Tyapp (s2, l2) ->
      s1 == s2 && List.length l1 = List.length l2 &&
	  List.for_all2 unify l1 l2
  | Tyapp _, _ | _, Tyapp _ ->
      false
	(* other cases *)
  | Tyvar {user=true; tag=t1}, Tyvar {user=true; tag=t2} -> 
      t1 = t2

216
(** Destructive typing environment, that is
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
217
    environment + local variables.
218
    It is only local to this module and created with [create_denv] below. *)
219 220

type denv = { 
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
221
  th : theory_uc; (* the theory under construction *)
222 223
  utyvars : (string, type_var) Hashtbl.t; (* user type variables *)
  dvars : dty M.t; (* local variables, to be bound later *)
224 225
}

226 227
let create_denv th = { 
  th = th; 
228 229 230
  utyvars = Hashtbl.create 17; 
  dvars = M.empty;
}
231

232 233 234 235
let find_user_type_var x env =
  try
    Hashtbl.find env.utyvars x
  with Not_found ->
236
    (* TODO: shouldn't we localize this ident? *)
237 238
    let v = create_tvsymbol (id_fresh x) in
    let v = create_type_var ~user:true v in
239 240 241
    Hashtbl.add env.utyvars x v;
    v
 
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
242 243
(* Specialize *)

244
module Htv = Hid
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
245

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
246
let find_type_var ~loc env tv =
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
247 248 249
  try
    Htv.find env tv
  with Not_found ->
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
250
    let v = create_type_var ~loc ~user:false tv in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
251 252 253
    Htv.add env tv v;
    v
 
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
254
let rec specialize ~loc env t = match t.ty_node with
255
  | Ty.Tyvar tv -> 
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
256
      Tyvar (find_type_var ~loc env tv)
257
  | Ty.Tyapp (s, tl) ->
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
258
      Tyapp (s, List.map (specialize ~loc env) tl)
259

260 261 262
(** generic find function using a path *)

let find_local_namespace {id=x; id_loc=loc} ns = 
263
  try Mnm.find x ns.ns_ns
264 265 266 267 268 269 270 271 272 273 274 275
  with Not_found -> error ~loc (UnboundNamespace x)

let rec find_namespace q ns = match q with
  | Qident t -> find_local_namespace t ns
  | Qdot (q, t) -> let ns = find_namespace q ns in find_local_namespace t ns

let rec find f q ns = match q with
  | Qident x -> f x ns
  | Qdot (m, x) -> let ns = find_namespace m ns in f x ns

(** specific find functions using a path *)

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
276
let find_local_tysymbol {id=x; id_loc=loc} ns = 
277
  try Mnm.find x ns.ns_ts
278 279
  with Not_found -> error ~loc (UnboundType x)

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
280 281 282
let find_tysymbol_ns p ns =
  find find_local_tysymbol p ns

283
let find_tysymbol p th = 
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
284
  find_tysymbol_ns p (get_namespace th)
285

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
286
let specialize_tysymbol ~loc x env =
287
  let s = find_tysymbol x env.th in
288
  let env = Htv.create 17 in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
289
  s, List.map (find_type_var ~loc env) s.ts_args
290
	
291
let find_fsymbol {id=x; id_loc=loc} ns = 
292
  try Mnm.find x ns.ns_fs
293 294
  with Not_found -> error ~loc (UnboundSymbol x)

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
295 296 297
let find_fsymbol_ns p ns = 
  find find_fsymbol p ns

298
let find_fsymbol p th = 
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
299
  find_fsymbol_ns p (get_namespace th)
300

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
301
let specialize_fsymbol ~loc s =
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
302 303
  let tl, t = s.fs_scheme in
  let env = Htv.create 17 in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
304
  s, List.map (specialize ~loc env) tl, specialize ?loc env t
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
305

306
let find_psymbol {id=x; id_loc=loc} ns = 
307
  try Mnm.find x ns.ns_ps
308 309
  with Not_found -> error ~loc (UnboundSymbol x)

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
310 311 312
let find_psymbol_ns p ns =
  find find_psymbol p ns

313
let find_psymbol p th =
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
314
  find_psymbol_ns p (get_namespace th)
315

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
316
let specialize_psymbol ~loc s =
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
317
  let env = Htv.create 17 in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
318
  s, List.map (specialize ~loc env) s.ps_scheme
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
319

320 321
(** Typing types *)

322
let rec qloc = function
323
  | Qident x -> x.id_loc
324
  | Qdot (m, x) -> Loc.join (qloc m) x.id_loc
325 326

(* parsed types -> intermediate types *)
327 328 329 330 331

let rec type_inst s ty = match ty.ty_node with
  | Ty.Tyvar n -> Mid.find n s
  | Ty.Tyapp (ts, tyl) -> Tyapp (ts, List.map (type_inst s) tyl)

332
let rec dty env = function
333
  | PPTtyvar {id=x} -> 
334
      Tyvar (find_user_type_var x env)
335
  | PPTtyapp (p, x) ->
336
      let loc = qloc x in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
337
      let ts, tv = specialize_tysymbol ~loc x env in
338 339 340
      let np = List.length p in
      let a = List.length tv in
      if np <> a then error ~loc (TypeArity (x, a, np));
341 342 343 344 345 346 347 348
      let tyl = List.map (dty env) p in
      match ts.ts_def with
	| None -> 
	    Tyapp (ts, tyl)
	| Some ty -> 
	    let add m v t = Mid.add v t m in
            let s = List.fold_left2 add Mid.empty ts.ts_args tyl in
	    type_inst s ty
349 350

(* intermediate types -> types *)
351
let rec ty_of_dty = function
352
  | Tyvar { type_val = Some t } ->
353
      ty_of_dty t
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
354 355
  | Tyvar { type_val = None; user = false; type_var_loc = loc } ->
      errorm ?loc "undefined type variable"
356 357 358
  | Tyvar { tvsymbol = tv } ->
      Ty.ty_var tv
  | Tyapp (s, tl) ->
359
      Ty.ty_app s (List.map ty_of_dty tl)
360

361
(** Typing terms and formulas *)
362 363 364 365

type dterm = { dt_node : dterm_node; dt_ty : dty }

and dterm_node =
366
  | Tvar of string
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
367
  | Tconst of constant
368 369 370
  | Tapp of fsymbol * dterm list
  | Tlet of dterm * string * dterm
(*   | Tcase of dterm * tbranch list *)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
371
  | Tnamed of string * dterm
372 373 374 375
  | Teps of string * dfmla

and dfmla = 
  | Fapp of psymbol * dterm list
376
  | Fquant of quant * string list * dty * dtrigger list list * dfmla
377 378 379 380 381
  | Fbinop of binop * dfmla * dfmla
  | Fnot of dfmla
  | Ftrue
  | Ffalse
  | Fif of dfmla * dfmla * dfmla
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
382
  | Flet of dterm * string * dfmla
383
(*   | Fcase of dterm * (pattern * dfmla) list *)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
384
  | Fnamed of string * dfmla
385

386 387 388 389
and dtrigger =
  | TRterm of dterm
  | TRfmla of dfmla

390 391 392 393 394 395
let binop = function
  | PPand -> Fand
  | PPor -> For
  | PPimplies -> Fimplies
  | PPiff -> Fiff

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
396 397 398 399 400
let rec trigger_not_a_term_exn = function
  | Error (TermExpected | UnboundSymbol _) -> true
  | Loc.Located (_, exn) -> trigger_not_a_term_exn exn
  | _ -> false

401 402 403 404 405
let rec dterm env t = 
  let n, ty = dterm_node t.pp_loc env t.pp_desc in
  { dt_node = n; dt_ty = ty }

and dterm_node loc env = function
406 407 408 409 410 411
  | PPvar (Qident {id=x}) when M.mem x env.dvars ->
      (* local variable *)
      let ty = M.find x env.dvars in
      Tvar x, ty
  | PPvar x -> 
      (* 0-arity symbol (constant) *)
Jean-Christophe Filliâtre's avatar
egalite  
Jean-Christophe Filliâtre committed
412
      let s = find_fsymbol x env.th in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
413
      let s, tyl, ty = specialize_fsymbol ~loc s in
414 415 416
      let n = List.length tyl in
      if n > 0 then error ~loc (BadNumberOfArguments (s.fs_name, 0, n));
      Tapp (s, []), ty
417
  | PPapp (x, tl) ->
Jean-Christophe Filliâtre's avatar
egalite  
Jean-Christophe Filliâtre committed
418
      let s = find_fsymbol x env.th in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
419
      let s, tyl, ty = specialize_fsymbol ~loc s in
420 421
      let tl = dtype_args s.fs_name loc env tyl tl in
      Tapp (s, tl), ty
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
422
  | PPconst (ConstInt _ as c) ->
423
      Tconst c, Tyapp (Ty.ts_int, [])
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
424
  | PPconst (ConstReal _ as c) ->
425
      Tconst c, Tyapp (Ty.ts_real, [])
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
426 427 428 429 430 431
  | PPlet ({id=x}, e1, e2) ->
      let e1 = dterm env e1 in
      let ty = e1.dt_ty in
      let env = { env with dvars = M.add x ty env.dvars } in
      let e2 = dterm env e2 in
      Tlet (e1, x, e2), e2.dt_ty
432 433
  | PPmatch _ ->
      assert false (* TODO *)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
434 435 436
  | PPnamed (x, e1) ->
      let e1 = dterm env e1 in
      Tnamed (x, e1), e1.dt_ty
437 438 439
  | PPexists _ | PPforall _ | PPif _ 
  | PPprefix _ | PPinfix _ | PPfalse | PPtrue ->
      error ~loc TermExpected
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
440

441 442 443 444 445 446 447 448 449 450 451
and dfmla env e = match e.pp_desc with
  | PPtrue ->
      Ftrue
  | PPfalse ->
      Ffalse
  | PPprefix (PPnot, a) ->
      Fnot (dfmla env a)
  | PPinfix (a, (PPand | PPor | PPimplies | PPiff as op), b) ->
      Fbinop (binop op, dfmla env a, dfmla env b)
  | PPif (a, b, c) ->
      Fif (dfmla env a, dfmla env b, dfmla env c)  
452
  | PPforall (idl, ty, trl, a) ->
453
      let ty = dty env ty in
454 455 456 457 458 459 460 461
      let env, idl = 
	map_fold_left
	  (fun env {id=x} -> { env with dvars = M.add x ty env.dvars }, x)
	  env idl
      in
      let trigger e = (* FIXME? *)
	try 
	  TRterm (dterm env e) 
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
462 463
	with exn when trigger_not_a_term_exn exn ->
	  TRfmla (dfmla env e) 
464 465 466 467
      in
      let trl = List.map (List.map trigger) trl in
      Fquant (Fforall, idl, ty, trl, dfmla env a)
  | PPexists ({id=x}, ty, a) -> (* TODO: triggers? *)
468
      let ty = dty env ty in
469
      let env = { env with dvars = M.add x ty env.dvars } in
470
      Fquant (Fexists, [x], ty, [], dfmla env a)
471
  | PPapp (x, tl) ->
Jean-Christophe Filliâtre's avatar
egalite  
Jean-Christophe Filliâtre committed
472
      let s = find_psymbol x env.th in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
473
      let s, tyl = specialize_psymbol ~loc:e.pp_loc s in
474 475
      let tl = dtype_args s.ps_name e.pp_loc env tyl tl in
      Fapp (s, tl)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
476 477 478 479 480 481
  | PPlet ({id=x}, e1, e2) ->
      let e1 = dterm env e1 in
      let ty = e1.dt_ty in
      let env = { env with dvars = M.add x ty env.dvars } in
      let e2 = dfmla env e2 in
      Flet (e1, x, e2)
482 483
  | PPmatch _ ->
      assert false (* TODO *)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
484 485 486
  | PPnamed (x, f1) ->
      let f1 = dfmla env f1 in
      Fnamed (x, f1)
487 488 489 490
  | PPvar _ -> 
      assert false (* TODO *)
  | PPconst _ | PPprefix (PPneg, _) ->
      error ~loc:e.pp_loc PredicateExpected
491

492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513
and dtype_args s loc env el tl =
  let n = List.length el and m = List.length tl in
  if n <> m then error ~loc (BadNumberOfArguments (s, m, n));
  let rec check_arg = function
    | [], [] -> 
	[]
    | a :: al, t :: bl ->
	let loc = t.pp_loc in
	let t = dterm env t in
	if not (unify a t.dt_ty) then
	  error ~loc (TermExpectedType ((fun f -> print_dty f t.dt_ty),
					(fun f -> print_dty f a)));
	t :: check_arg (al, bl)
    | _ ->
	assert false
  in
  check_arg (el, tl)

let rec term env t = match t.dt_node with
  | Tvar x ->
      assert (M.mem x env);
      t_var (M.find x env)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
514
  | Tconst c ->
515
      t_const c (ty_of_dty t.dt_ty)
516
  | Tapp (s, tl) ->
517
      t_app s (List.map (term env) tl) (ty_of_dty t.dt_ty)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
518 519 520 521 522 523 524
  | Tlet (e1, x, e2) ->
      let ty = ty_of_dty e1.dt_ty in
      let e1 = term env e1 in 
      let v = create_vsymbol (id_fresh x) ty in
      let env = M.add x v env in
      let e2 = term env e2 in
      t_let v e1 e2
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
525 526 527
  | Tnamed (x, e1) ->
      let e1 = term env e1 in
      t_label_add x e1
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
528 529
  | Teps _ ->
      assert false (*TODO*)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
530

531 532 533 534 535 536 537 538 539 540 541
and fmla env = function
  | Ftrue ->
      f_true
  | Ffalse ->
      f_false 
  | Fnot f ->
      f_not (fmla env f)
  | Fbinop (op, f1, f2) ->
      f_binary op (fmla env f1) (fmla env f2)
  | Fif (f1, f2, f3) ->
      f_if (fmla env f1) (fmla env f2) (fmla env f3)
542
  | Fquant (q, xl, ty, trl, f1) ->
543
      (* TODO: shouldn't we localize this ident? *)
544 545 546 547 548 549 550 551
      let ty = ty_of_dty ty in
      let env, vl = 
	map_fold_left 
	  (fun env x -> 
	     let v = create_vsymbol (id_fresh x) ty in M.add x v env, v) 
	  env xl 
      in
      f_quant q vl [] (fmla env f1)
552 553
  | Fapp (s, tl) ->
      f_app s (List.map (term env) tl)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
554
  | Flet (e1, x, f2) ->
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
555 556 557 558
      let ty = ty_of_dty e1.dt_ty in
      let e1 = term env e1 in 
      let v = create_vsymbol (id_fresh x) ty in
      let env = M.add x v env in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
559 560 561
      let f2 = fmla env f2 in
      f_let v e1 f2
  | Fnamed (x, f1) ->
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
562
      let f1 = fmla env f1 in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
563
      f_label_add x f1
564

565
(** Typing declarations, that is building environments. *)
566 567 568

open Ptree

569
let add_types loc dl th =
570
  let ns = get_namespace th in
571 572 573 574
  let def = 
    List.fold_left 
      (fun def d -> 
	 let id = d.td_ident in
575 576
	 if M.mem id.id def || Mnm.mem id.id ns.ns_ts then 
	   error ~loc:id.id_loc (ClashType id.id);
577 578
	 M.add id.id d def) 
      M.empty dl 
579
  in
580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595
  let tysymbols = Hashtbl.create 17 in
  let rec visit x = 
    try
      match Hashtbl.find tysymbols x with
	| None -> error CyclicTypeDef
	| Some ts -> ts
    with Not_found ->
      Hashtbl.add tysymbols x None;
      let d = M.find x def in
      let id = d.td_ident.id in
      let vars = Hashtbl.create 17 in
      let vl = 
	List.map 
	  (fun v -> 
	     if Hashtbl.mem vars v.id then 
	       error ~loc:v.id_loc (DuplicateTypeVar v.id);
596
	     let i = create_tvsymbol (id_user v.id v.id_loc) in
597 598 599 600
	     Hashtbl.add vars v.id i;
	     i)
	  d.td_params 
      in
601
      let id = id_user id d.td_ident.id_loc in
602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629
      let ts = match d.td_def with
	| TDalias ty -> 
	    let rec apply = function
	      | PPTtyvar v -> 
		  begin 
		    try ty_var (Hashtbl.find vars v.id)
		    with Not_found -> error ~loc:v.id_loc (UnboundTypeVar v.id)
		  end
	      | PPTtyapp (tyl, q) ->
		  let ts = match q with
		    | Qident x when M.mem x.id def ->
			visit x.id
		    | Qident _ | Qdot _ ->
			find_tysymbol q th
		  in
		  try
		    ty_app ts (List.map apply tyl)
		  with Ty.BadTypeArity ->
		    error ~loc:(qloc q) (TypeArity (q, List.length ts.ts_args,
						    List.length tyl))
	    in
	    create_tysymbol id vl (Some (apply ty))
	| TDabstract | TDalgebraic _ -> 
	    create_tysymbol id vl None
      in
      Hashtbl.add tysymbols x (Some ts);
      ts
  in
630 631 632 633 634 635
  let th' = 
    let tsl = 
      M.fold (fun x _ tsl -> let ts = visit x in (ts, Tabstract) :: tsl) def []
    in
    add_decl th (create_type tsl)
  in
636
  let decl d = 
637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661
    let ts, th' = match Hashtbl.find tysymbols d.td_ident.id with
      | None -> 
	  assert false
      | Some ts -> 
	  let th' = create_denv th' in
	  let vars = th'.utyvars in
	  List.iter 
	    (fun v -> 
	       Hashtbl.add vars v.id_short (create_type_var ~user:true v)) 
	    ts.ts_args;
	  ts, th'
    in
    let d = match d.td_def with
      | TDabstract | TDalias _ -> 
	  Tabstract
      | TDalgebraic cl -> 
	  let ty = ty_app ts (List.map ty_var ts.ts_args) in
	  let constructor (loc, id, pl) = 
	    let param (_, t) = ty_of_dty (dty th' t) in
	    let tyl = List.map param pl in
	    create_fsymbol (id_user id.id id.id_loc) (tyl, ty) true
	  in
	  Talgebraic (List.map constructor cl)
    in
    ts, d
662 663
  in
  let dl = List.map decl dl in
664
  add_decl th (create_type dl)
665

Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
666 667 668 669
let env_of_vsymbol_list vl =
  List.fold_left (fun env v -> M.add v.vs_name.id_short v env) M.empty vl

let add_logics loc dl th =
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
670
  let ns = get_namespace th in
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
671 672
  let fsymbols = Hashtbl.create 17 in
  let psymbols = Hashtbl.create 17 in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
673
  let denvs = Hashtbl.create 17 in
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
674 675 676
  (* 1. create all symbols and make an environment with these symbols *)
  let create_symbol th d = 
    let id = d.ld_ident.id in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
677
    if Hashtbl.mem denvs id || Mnm.mem id ns.ns_fs then error ~loc (Clash id);
678
    let v = id_user id loc in
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
679
    let denv = create_denv th in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
680
    Hashtbl.add denvs id denv;
681
    let type_ty (_,t) = ty_of_dty (dty denv t) in
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
682 683 684 685 686
    let pl = List.map type_ty d.ld_params in
    match d.ld_type with
      | None -> (* predicate *)
	  let ps = create_psymbol v pl in
	  Hashtbl.add psymbols id ps;
687
	  add_decl th (create_logic [Lpredicate (ps, None)])
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
688 689 690 691
      | Some t -> (* function *)
	  let t = type_ty (None, t) in
	  let fs = create_fsymbol v (pl, t) false in
	  Hashtbl.add fsymbols id fs;
692
	  add_decl th (create_logic [Lfunction (fs, None)])
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
693 694 695 696 697 698 699 700 701
  in
  let th' = List.fold_left create_symbol th dl in
  (* 2. then type-check all definitions *)
  let type_decl d = 
    let id = d.ld_ident.id in
    let dadd_var denv (x, ty) = match x with
      | None -> denv
      | Some id -> { denv with dvars = M.add id.id (dty denv ty) denv.dvars }
    in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
702 703 704
    let denv = Hashtbl.find denvs id in
    let denv = { denv with th = th' } in
    let denv = List.fold_left dadd_var denv d.ld_params in
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
705 706
    let create_var (x, _) ty = 
      let id = match x with 
707 708
	| None -> id_fresh "%x"
	| Some id -> id_user id.id id.id_loc
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
709 710 711
      in
      create_vsymbol id ty
    in
712
    let mk_vlist = List.map2 create_var d.ld_params in
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
713 714 715
    match d.ld_type with
    | None -> (* predicate *)
	let ps = Hashtbl.find psymbols id in
716 717
        let defn = match d.ld_def with
	  | None -> None
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
718 719
	  | Some f -> 
	      let f = dfmla denv f in
720
	      let vl = mk_vlist ps.ps_scheme in
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
721
	      let env = env_of_vsymbol_list vl in
722 723 724
              Some (make_ps_defn ps vl (fmla env f))
        in
        Lpredicate (ps, defn)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
725
    | Some ty -> (* function *)
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
726
	let fs = Hashtbl.find fsymbols id in
727 728
        let defn = match d.ld_def with
	  | None -> None
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
729
	  | Some t -> 
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
730
	      let loc = t.pp_loc in
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
731
	      let t = dterm denv t in
732
	      let vl = mk_vlist (fst fs.fs_scheme) in
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
733
	      let env = env_of_vsymbol_list vl in
734 735 736 737 738 739
              try Some (make_fs_defn fs vl (term env t))
	      with _ -> error ~loc (TermExpectedType 
                ((fun f -> print_dty f t.dt_ty),
                 (fun f -> print_dty f (dty denv ty))))
        in
        Lfunction (fs, defn)
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
740 741
  in
  let dl = List.map type_decl dl in
742
  add_decl th (create_logic dl)
743

744

745 746 747
let term env t =
  let denv = create_denv env in
  let t = dterm denv t in
748
  term M.empty t
749

Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
750 751 752 753 754
let fmla env f =
  let denv = create_denv env in
  let f = dfmla denv f in
  fmla M.empty f

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
755 756 757
let add_prop k loc s f th =
  let f = fmla th f in
  try
758
    add_decl th (create_prop k (id_user s.id loc) f)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
759 760
  with ClashSymbol _ ->
    error ~loc (Clash s.id)
761

762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787
let find_in_loadpath env f =
  let rec find c lp = match lp, c with
    | [], None -> 
	error ~loc:f.id_loc (NotInLoadpath f.id)
    | [], Some file ->
	file
    | dir :: lp, _ ->
	let file = Filename.concat dir f.id in
	if Sys.file_exists file then begin match c with
	  | None -> find (Some file) lp
	  | Some file' -> error ~loc:f.id_loc (AmbiguousPath (file, file'))
	end else
	  find c lp
  in
  find None env.loadpath

let locate_file env q = 
  let rec locate_dir = function
    | Qident d ->
	find_in_loadpath env d
    | Qdot (q, d) -> 
	let dir = locate_dir q in
	let dir = Filename.concat dir d.id in
	if not (Sys.file_exists dir) then error ~loc:d.id_loc (UnboundDir dir);
	dir
  in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
788 789 790 791 792 793 794 795 796
  match q with
    | Qident f -> 
	find_in_loadpath env { f with id = f.id ^ ".why" }
    | Qdot (p, f) -> 
	let dir = locate_dir p in 
	let file = Filename.concat dir f.id ^ ".why" in
	if not (Sys.file_exists file) then 
	  error ~loc:(qloc q) (UnboundFile file);
	file
797

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
798
let loaded_theories = Hashtbl.create 17 (* file -> string -> Theory.t *)
799 800

(* parse file and store all theories into parsed_theories *)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
801 802 803 804 805 806 807
let load_file file =
  let c = open_in file in
  let lb = Lexing.from_channel c in
  Loc.set_file file lb;
  let tl = Lexer.parse_logic_file lb in 
  close_in c;
  tl
808

Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
809
let prop_kind = function
810 811 812
  | Kaxiom -> Paxiom
  | Kgoal -> Pgoal
  | Klemma -> Plemma
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
813

814
let rec find_theory env q = match q with
815
  | Qident id -> 
816
      (* local theory *)
817 818 819 820 821
      begin 
	try M.find id.id env.theories 
	with Not_found -> error ~loc:id.id_loc (UnboundTheory id.id) 
      end
  | Qdot (f, id) ->
822 823
      (* theory in file f *)
      let file = locate_file env f in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
824 825 826 827 828 829 830 831 832 833 834 835
      if not (Hashtbl.mem loaded_theories file) then begin
	let tl = load_file file in
	let h = Hashtbl.create 17 in
	Hashtbl.add loaded_theories file h;
	let env = { env with theories = M.empty } in
	let add env pt =
	  let t, env = add_theory env pt in
	  Hashtbl.add h t.th_name.id_short t;
	  env
	in
	ignore (List.fold_left add env tl);
      end;
836
      let h = Hashtbl.find loaded_theories file in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
837 838
      try Hashtbl.find h id.id
      with Not_found -> error ~loc:id.id_loc (UnboundTheory id.id)
839 840

and type_theory env id pt =
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
841
  (* TODO: use long name *)
842
  let n = id_user id.id id.id_loc in
843
  let th = create_theory n in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
844
  let th = add_decls env th pt.pt_decl in
845 846 847
  close_theory th

and add_decls env th = List.fold_left (add_decl env) th
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
848

849
and add_decl env th = function
850 851
  | TypeDecl (loc, dl) ->
      add_types loc dl th
Jean-Christophe Filliâtre's avatar
logic  
Jean-Christophe Filliâtre committed
852 853
  | Logic (loc, dl) ->
      add_logics loc dl th
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
854 855
  | Prop (loc, k, s, f) ->
      add_prop (prop_kind k) loc s f th
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
856
  | UseClone (loc, use, subst) ->
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
857
      let t = find_theory env use.use_theory in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877
      let use_or_clone th = match subst with
	| None -> 
	    use_export th t
	| Some s -> 
	    let add_ts m (p, q) = 
	      Mts.add (find_tysymbol_ns p t.th_export) (find_tysymbol q th) m
	    in
	    let add_fs m (p, q) = 
	      Mfs.add (find_fsymbol_ns p t.th_export) (find_fsymbol q th) m
	    in
	    let add_ps m (p, q) = 
	      Mps.add (find_psymbol_ns p t.th_export) (find_psymbol q th) m
	    in
	    let s = 
	      { inst_ts = List.fold_left add_ts Mts.empty s.ts_subst;
		inst_fs = List.fold_left add_fs Mfs.empty s.fs_subst;
		inst_ps = List.fold_left add_ps Mps.empty s.ps_subst; }
	    in
	    clone_export th t s
      in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
878
      let n = match use.use_as with 
879 880
	| None -> t.th_name.id_short
	| Some x -> x.id
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
881
      in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
882
      begin try match use.use_imp_exp with
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
883 884 885
	| Nothing ->
	    (* use T = namespace T use_export T end *)
	    let th = open_namespace th in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
886
	    let th = use_or_clone th in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
887 888 889 890
	    close_namespace th n ~import:false
	| Import ->
	    (* use import T = namespace T use_export T end import T *)
	    let th = open_namespace th in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
891
	    let th = use_or_clone th in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
892 893
	    close_namespace th n ~import:true
	| Export ->
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
894
	    use_or_clone th 
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
895 896
      with Theory.ClashSymbol s ->
	error ~loc (Clash s)
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
897
      end
898 899
  | Namespace (_, {id=id; id_loc=loc}, dl) ->
      let ns = get_namespace th in
900
      if Mnm.mem id ns.ns_ns then error ~loc (ClashNamespace id);
901
      let th = open_namespace th in
Jean-Christophe Filliâtre's avatar
Jean-Christophe Filliâtre committed
902
      let th = add_decls env th dl in
903
      close_namespace th id ~import:false