1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
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
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
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
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
(************************************************************************)
(*         *   The Coq Proof Assistant / The Coq Development Team       *)
(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2019       *)
(* <O___,, *       (see CREDITS file for the list of authors)           *)
(*   \VV/  **************************************************************)
(*    //   *    This file is distributed under the terms of the         *)
(*         *     GNU Lesser General Public License Version 2.1          *)
(*         *     (see LICENSE file for the text of the license)         *)
(************************************************************************)

open CErrors
open Util
open Pp
open Names
open Libnames
open Globnames

type object_prefix = {
  obj_dir : DirPath.t;
  obj_mp  : ModPath.t;
}

let eq_op op1 op2 =
  DirPath.equal op1.obj_dir op2.obj_dir &&
  ModPath.equal op1.obj_mp  op2.obj_mp

(* to this type are mapped DirPath.t's in the nametab *)
module GlobDirRef = struct
  type t =
    | DirOpenModule of object_prefix
    | DirOpenModtype of object_prefix
    | DirOpenSection of object_prefix
    | DirModule of object_prefix

  let equal r1 r2 = match r1, r2 with
    | DirOpenModule op1, DirOpenModule op2 -> eq_op op1 op2
    | DirOpenModtype op1, DirOpenModtype op2 -> eq_op op1 op2
    | DirOpenSection op1, DirOpenSection op2 -> eq_op op1 op2
    | DirModule op1, DirModule op2 -> eq_op op1 op2
    | _ -> false

end

exception GlobalizationError of qualid

let error_global_not_found qid =
  Loc.raise ?loc:qid.CAst.loc (GlobalizationError qid)

(* The visibility can be registered either
   - for all suffixes not shorter then a given int - when the object
     is loaded inside a module
   or
   - for a precise suffix, when the module containing (the module
     containing ...) the object is open (imported)
*)
type visibility = Until of int | Exactly of int

let map_visibility f = function
  | Until i -> Until (f i)
  | Exactly i -> Exactly (f i)

(* Data structure for nametabs *******************************************)


(* This module type will be instantiated by [full_path] of [DirPath.t] *)
(* The [repr] function is assumed to return the reversed list of idents. *)
module type UserName = sig
  type t
  val equal : t -> t -> bool
  val to_string : t -> string
  val repr : t -> Id.t * module_ident list
end

module type EqualityType =
sig
  type t
  val equal : t -> t -> bool
end

(* A ['a t] is a map from [user_name] to ['a], with possible lookup by
   partially qualified names of type [qualid]. The mapping of
   partially qualified names to ['a] is determined by the [visibility]
   parameter of [push].

   The [shortest_qualid] function given a user_name Coq.A.B.x, tries
   to find the shortest among x, B.x, A.B.x and Coq.A.B.x that denotes
   the same object.
*)
module type NAMETREE = sig
  type elt
  type t
  type user_name

  val empty : t
  val push : visibility -> user_name -> elt -> t -> t
  val locate : qualid -> t -> elt
  val find : user_name -> t -> elt
  val exists : user_name -> t -> bool
  val user_name : qualid -> t -> user_name
  val shortest_qualid : ?loc:Loc.t -> Id.Set.t -> user_name -> t -> qualid
  val find_prefixes : qualid -> t -> elt list

  (** Matches a prefix of [qualid], useful for completion *)
  val match_prefixes : qualid -> t -> elt list
end

module Make (U : UserName) (E : EqualityType) : NAMETREE
  with type user_name = U.t and type elt = E.t =
struct
  type elt = E.t

  (* A name became inaccessible, even with absolute qualification.
     Example:
     Module F (X : S). Module X.
     The argument X of the functor F is masked by the inner module X.
   *)
  let warn_masking_absolute =
    CWarnings.create ~name:"masking-absolute-name" ~category:"deprecated"
      (fun n -> str ("Trying to mask the absolute name \"" ^ U.to_string n ^ "\"!"))

  type user_name = U.t

  type path_status =
      Nothing
    | Relative of user_name * elt
    | Absolute of user_name * elt

  (* Dictionaries of short names *)
  type nametree =
      { path : path_status;
        map : nametree ModIdmap.t }

  let mktree p m = { path=p; map=m }
  let empty_tree = mktree Nothing ModIdmap.empty

  type t = nametree Id.Map.t

  let empty = Id.Map.empty

  (* [push_until] is used to register [Until vis] visibility and
     [push_exactly] to [Exactly vis] and [push_tree] chooses the right one*)

  let rec push_until uname o level tree = function
    | modid :: path ->
        let modify _ mc = push_until uname o (level-1) mc path in
        let map =
          try ModIdmap.modify modid modify tree.map
          with Not_found ->
            let ptab = modify () empty_tree in
            ModIdmap.add modid ptab tree.map
        in
        let this =
          if level <= 0 then
            match tree.path with
              | Absolute (n,_) ->
                  (* This is an absolute name, we must keep it
                     otherwise it may become unaccessible forever *)
                warn_masking_absolute n; tree.path
              | Nothing
              | Relative _ -> Relative (uname,o)
          else tree.path
        in
        mktree this map
    | [] ->
        match tree.path with
          | Absolute (uname',o') ->
              if E.equal o' o then begin
                assert (U.equal uname uname');
                tree
                  (* we are putting the same thing for the second time :) *)
              end
              else
                (* This is an absolute name, we must keep it otherwise it may
                   become unaccessible forever *)
                (* But ours is also absolute! This is an error! *)
                user_err Pp.(str @@ "Cannot mask the absolute name \""
                                   ^ U.to_string uname' ^ "\"!")
          | Nothing
          | Relative _ -> mktree (Absolute (uname,o)) tree.map

let rec push_exactly uname o level tree = function
| [] ->
  anomaly (Pp.str "Prefix longer than path! Impossible!")
| modid :: path ->
  if Int.equal level 0 then
    let this =
      match tree.path with
        | Absolute (n,_) ->
            (* This is an absolute name, we must keep it
                otherwise it may become unaccessible forever *)
            warn_masking_absolute n; tree.path
        | Nothing
        | Relative _ -> Relative (uname,o)
    in
    mktree this tree.map
  else (* not right level *)
    let modify _ mc = push_exactly uname o (level-1) mc path in
    let map =
      try ModIdmap.modify modid modify tree.map
      with Not_found ->
        let ptab = modify () empty_tree in
        ModIdmap.add modid ptab tree.map
    in
    mktree tree.path map


let push visibility uname o tab =
  let id,dir = U.repr uname in
  let modify _ ptab = match visibility with
    | Until i -> push_until uname o (i-1) ptab dir
    | Exactly i -> push_exactly uname o (i-1) ptab dir
  in
  try Id.Map.modify id modify tab
  with Not_found ->
    let ptab = modify () empty_tree in
    Id.Map.add id ptab tab


let rec search tree = function
  | modid :: path -> search (ModIdmap.find modid tree.map) path
  | [] -> tree.path

let find_node qid tab =
  let (dir,id) = repr_qualid qid in
    search (Id.Map.find id tab) (DirPath.repr dir)

let locate qid tab =
  let o = match find_node qid tab with
    | Absolute (uname,o) | Relative (uname,o) -> o
    | Nothing -> raise Not_found
  in
    o

let user_name qid tab =
  let uname = match find_node qid tab with
    | Absolute (uname,o) | Relative (uname,o) -> uname
    | Nothing -> raise Not_found
  in
    uname

let find uname tab =
  let id,l = U.repr uname in
    match search (Id.Map.find id tab) l with
        Absolute (_,o) -> o
      | _ -> raise Not_found

let exists uname tab =
  try
    let _ = find uname tab in
      true
  with
      Not_found -> false

let shortest_qualid ?loc ctx uname tab =
  let id,dir = U.repr uname in
  let hidden = Id.Set.mem id ctx in
  let rec find_uname pos dir tree =
    let is_empty = match pos with [] -> true | _ -> false in
    match tree.path with
    | Absolute (u,_) | Relative (u,_)
          when U.equal u uname && not (is_empty && hidden) -> List.rev pos
    | _ ->
        match dir with
            [] -> raise Not_found
          | id::dir -> find_uname (id::pos) dir (ModIdmap.find id tree.map)
  in
  let ptab = Id.Map.find id tab in
  let found_dir = find_uname [] dir ptab in
    make_qualid ?loc (DirPath.make found_dir) id

let push_node node l =
  match node with
  | Absolute (_,o) | Relative (_,o) when not (List.mem_f E.equal o l) -> o::l
  | _ -> l

let rec flatten_idmap tab l =
  let f _ tree l = flatten_idmap tree.map (push_node tree.path l) in
  ModIdmap.fold f tab l

let rec search_prefixes tree = function
  | modid :: path -> search_prefixes (ModIdmap.find modid tree.map) path
  | [] -> List.rev (flatten_idmap tree.map (push_node tree.path []))

let find_prefixes qid tab =
  try
    let (dir,id) = repr_qualid qid in
    search_prefixes (Id.Map.find id tab) (DirPath.repr dir)
  with Not_found -> []

let match_prefixes =
  let cprefix x y = CString.(compare x (sub y 0 (min (length x) (length y)))) in
  fun qid tab ->
    try
      let (dir,id) = repr_qualid qid in
      let id_prefix = cprefix Id.(to_string id) in
      let matches = Id.Map.filter_range (fun x -> id_prefix Id.(to_string x)) tab in
      let matches = Id.Map.mapi (fun _key tab -> search_prefixes tab (DirPath.repr dir)) matches in
      (* Coq's flatten is "magical", so this is not so bad perf-wise *)
      CList.flatten @@ Id.Map.(fold (fun _ r l -> r :: l) matches [])
    with Not_found -> []

end

(* Global name tables *************************************************)

module FullPath =
struct
  type t = full_path
  let equal = eq_full_path
  let to_string = string_of_path
  let repr sp =
    let dir,id = repr_path sp in
      id, (DirPath.repr dir)
end

module ExtRefEqual = ExtRefOrdered
module MPEqual = Names.ModPath

module ExtRefTab = Make(FullPath)(ExtRefEqual)
module MPTab = Make(FullPath)(MPEqual)

type ccitab = ExtRefTab.t
let the_ccitab = Summary.ref ~name:"ccitab" (ExtRefTab.empty : ccitab)

type mptab = MPTab.t
let the_modtypetab = Summary.ref ~name:"modtypetab" (MPTab.empty : mptab)

module DirPath' =
struct
  include DirPath
  let repr dir = match DirPath.repr dir with
    | [] -> anomaly (Pp.str "Empty dirpath.")
    | id :: l -> (id, l)
end

module DirTab = Make(DirPath')(GlobDirRef)

(* If we have a (closed) module M having a submodule N, than N does not
   have the entry in [the_dirtab]. *)
type dirtab = DirTab.t
let the_dirtab = Summary.ref ~name:"dirtab" (DirTab.empty : dirtab)

module UnivIdEqual =
struct
  type t = Univ.Level.UGlobal.t
  let equal = Univ.Level.UGlobal.equal
end
module UnivTab = Make(FullPath)(UnivIdEqual)
type univtab = UnivTab.t
let the_univtab = Summary.ref ~name:"univtab" (UnivTab.empty : univtab)

(* Reversed name tables ***************************************************)

(* This table translates extended_global_references back to section paths *)
module Globrevtab = HMap.Make(ExtRefOrdered)

type globrevtab = full_path Globrevtab.t
let the_globrevtab = Summary.ref ~name:"globrevtab" (Globrevtab.empty : globrevtab)


type mprevtab = DirPath.t MPmap.t
let the_modrevtab = Summary.ref ~name:"modrevtab" (MPmap.empty : mprevtab)

type mptrevtab = full_path MPmap.t
let the_modtyperevtab = Summary.ref ~name:"modtyperevtab" (MPmap.empty : mptrevtab)

module UnivIdOrdered =
struct
  type t = Univ.Level.UGlobal.t
  let hash = Univ.Level.UGlobal.hash
  let compare = Univ.Level.UGlobal.compare
end

module UnivIdMap = HMap.Make(UnivIdOrdered)

type univrevtab = full_path UnivIdMap.t
let the_univrevtab = Summary.ref ~name:"univrevtab" (UnivIdMap.empty : univrevtab)

(* Push functions *********************************************************)

(* This is for permanent constructions (never discharged -- but with
   possibly limited visibility, i.e. Theorem, Lemma, Definition, Axiom,
   Parameter but also Remark and Fact) *)

let push_xref visibility sp xref =
  match visibility with
    | Until _ ->
        the_ccitab := ExtRefTab.push visibility sp xref !the_ccitab;
        the_globrevtab := Globrevtab.add xref sp !the_globrevtab
    | _ ->
        begin
          if ExtRefTab.exists sp !the_ccitab then
            let open GlobRef in
            match ExtRefTab.find sp !the_ccitab with
              | TrueGlobal( ConstRef _) | TrueGlobal( IndRef _) |
                    TrueGlobal( ConstructRef _) as xref ->
                  the_ccitab := ExtRefTab.push visibility sp xref !the_ccitab;
              | _ -> 
                  the_ccitab := ExtRefTab.push visibility sp xref !the_ccitab;
            else
              the_ccitab := ExtRefTab.push visibility sp xref !the_ccitab;
        end

let push_cci visibility sp ref =
  push_xref visibility sp (TrueGlobal ref)
    
(* This is for Syntactic Definitions *)
let push_syndef visibility sp kn =
  push_xref visibility sp (SynDef kn)

let push = push_cci

let push_modtype vis sp kn =
  the_modtypetab := MPTab.push vis sp kn !the_modtypetab;
  the_modtyperevtab := MPmap.add kn sp !the_modtyperevtab

(* This is to remember absolute Section/Module names and to avoid redundancy *)
let push_dir vis dir dir_ref =
  the_dirtab := DirTab.push vis dir dir_ref !the_dirtab;
  match dir_ref with
  | GlobDirRef.DirModule { obj_mp; _ } -> the_modrevtab := MPmap.add obj_mp dir !the_modrevtab
  | _ -> ()

(* This is for global universe names *)

let push_universe vis sp univ =
  the_univtab := UnivTab.push vis sp univ !the_univtab;
  the_univrevtab := UnivIdMap.add univ sp !the_univrevtab

(* Locate functions *******************************************************)


(* This should be used when syntactic definitions are allowed *)
let locate_extended qid = ExtRefTab.locate qid !the_ccitab

(* This should be used when no syntactic definitions is expected *)
let locate qid = match locate_extended qid with
  | TrueGlobal ref -> ref
  | SynDef _ -> raise Not_found
let full_name_cci qid = ExtRefTab.user_name qid !the_ccitab

let locate_syndef qid = match locate_extended qid with
  | TrueGlobal _ -> raise Not_found
  | SynDef kn -> kn

let locate_modtype qid = MPTab.locate qid !the_modtypetab
let full_name_modtype qid = MPTab.user_name qid !the_modtypetab

let locate_universe qid = UnivTab.locate qid !the_univtab

let locate_dir qid = DirTab.locate qid !the_dirtab

let locate_module qid =
  match locate_dir qid with
    | GlobDirRef.DirModule { obj_mp ; _} -> obj_mp
    | _ -> raise Not_found

let full_name_module qid =
  match locate_dir qid with
    | GlobDirRef.DirModule { obj_dir ; _} -> obj_dir
    | _ -> raise Not_found

let locate_section qid =
  match locate_dir qid with
    | GlobDirRef.DirOpenSection { obj_dir; _ } -> obj_dir
    | _ -> raise Not_found

let locate_all qid =
  List.fold_right (fun a l -> match a with TrueGlobal a -> a::l | _ -> l)
    (ExtRefTab.find_prefixes qid !the_ccitab) []

let locate_extended_all qid = ExtRefTab.find_prefixes qid !the_ccitab

let locate_extended_all_dir qid = DirTab.find_prefixes qid !the_dirtab

let locate_extended_all_modtype qid = MPTab.find_prefixes qid !the_modtypetab

(* Completion *)
let completion_canditates qualid =
  ExtRefTab.match_prefixes qualid !the_ccitab

(* Derived functions *)

let locate_constant qid =
  let open GlobRef in
  match locate_extended qid with
    | TrueGlobal (ConstRef kn) -> kn
    | _ -> raise Not_found

let global_of_path sp =
  match ExtRefTab.find sp !the_ccitab with
    | TrueGlobal ref -> ref
    | _ -> raise Not_found

let extended_global_of_path sp = ExtRefTab.find sp !the_ccitab

let global qid =
  try match locate_extended qid with
    | TrueGlobal ref -> ref
    | SynDef _ ->
        user_err ?loc:qid.CAst.loc ~hdr:"global"
          (str "Unexpected reference to a notation: " ++
           pr_qualid qid)
  with Not_found ->
    error_global_not_found qid

(* Exists functions ********************************************************)

let exists_cci sp = ExtRefTab.exists sp !the_ccitab

let exists_dir dir = DirTab.exists dir !the_dirtab

let exists_modtype sp = MPTab.exists sp !the_modtypetab

let exists_universe kn = UnivTab.exists kn !the_univtab

(* Reverse locate functions ***********************************************)

let path_of_global ref =
  let open GlobRef in
  match ref with
    | VarRef id -> make_path DirPath.empty id
    | _ -> Globrevtab.find (TrueGlobal ref) !the_globrevtab

let dirpath_of_global ref =
  fst (repr_path (path_of_global ref))

let basename_of_global ref =
  snd (repr_path (path_of_global ref))

let path_of_syndef kn =
  Globrevtab.find (SynDef kn) !the_globrevtab

let dirpath_of_module mp =
  MPmap.find mp !the_modrevtab

let path_of_modtype mp =
  MPmap.find mp !the_modtyperevtab

let path_of_universe mp =
  UnivIdMap.find mp !the_univrevtab

(* Shortest qualid functions **********************************************)

let shortest_qualid_of_global ?loc ctx ref =
  let open GlobRef in
  match ref with
    | VarRef id -> make_qualid ?loc DirPath.empty id
    | _ ->
        let sp = Globrevtab.find (TrueGlobal ref) !the_globrevtab in
        ExtRefTab.shortest_qualid ?loc ctx sp !the_ccitab

let shortest_qualid_of_syndef ?loc ctx kn =
  let sp = path_of_syndef kn in
    ExtRefTab.shortest_qualid ?loc ctx sp !the_ccitab

let shortest_qualid_of_module ?loc mp =
  let dir = MPmap.find mp !the_modrevtab in
    DirTab.shortest_qualid ?loc Id.Set.empty dir !the_dirtab

let shortest_qualid_of_modtype ?loc kn =
  let sp = MPmap.find kn !the_modtyperevtab in
    MPTab.shortest_qualid ?loc Id.Set.empty sp !the_modtypetab

let shortest_qualid_of_universe ?loc kn =
  let sp = UnivIdMap.find kn !the_univrevtab in
    UnivTab.shortest_qualid ?loc Id.Set.empty sp !the_univtab

let pr_global_env env ref =
  try pr_qualid (shortest_qualid_of_global env ref)
  with Not_found as e ->
    if !Flags.debug then Feedback.msg_debug (Pp.str "pr_global_env not found"); raise e

let global_inductive qid =
  let open GlobRef in
  match global qid with
  | IndRef ind -> ind
  | ref ->
      user_err ?loc:qid.CAst.loc ~hdr:"global_inductive"
        (pr_qualid qid ++ spc () ++ str "is not an inductive type")