aboutsummaryrefslogtreecommitdiffhomepage
path: root/plugins/ltac/tacinterp.ml
blob: 04dd7d6e997dd7f0aa947f7e5807030f9b552da7 (plain)
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
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
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
630
631
632
633
634
635
636
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
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
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
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
(************************************************************************)
(*         *   The Coq Proof Assistant / The Coq Development Team       *)
(*  v      *   INRIA, CNRS and contributors - Copyright 1999-2018       *)
(* <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 Constrintern
open Patternops
open Pp
open CAst
open Namegen
open Genredexpr
open Glob_term
open Glob_ops
open Tacred
open CErrors
open Util
open Names
open Nameops
open Libnames
open Globnames
open Nametab
open Refiner
open Tacmach.New
open Tactic_debug
open Constrexpr
open Termops
open Tacexpr
open Genarg
open Geninterp
open Stdarg
open Tacarg
open Printer
open Pretyping
open Tactypes
open Locus
open Tacintern
open Taccoerce
open Proofview.Notations
open Context.Named.Declaration
open Ltac_pretype

let ltac_trace_info = Tactic_debug.ltac_trace_info

let has_type : type a. Val.t -> a typed_abstract_argument_type -> bool = fun v wit ->
  let Val.Dyn (t, _) = v in
  let t' = match val_tag wit with
  | Val.Base t' -> t'
  | _ -> assert false (** not used in this module *)
  in
  match Val.eq t t' with
  | None -> false
  | Some Refl -> true

let prj : type a. a Val.typ -> Val.t -> a option = fun t v ->
  let Val.Dyn (t', x) = v in
  match Val.eq t t' with
  | None -> None
  | Some Refl -> Some x

let in_list tag v =
  let tag = match tag with Val.Base tag -> tag | _ -> assert false in
  Val.Dyn (Val.typ_list, List.map (fun x -> Val.Dyn (tag, x)) v)
let in_gen wit v =
  let t = match val_tag wit with
  | Val.Base t -> t
  | _ -> assert false (** not used in this module *)
  in
  Val.Dyn (t, v)
let out_gen wit v =
  let t = match val_tag wit with
  | Val.Base t -> t
  | _ -> assert false (** not used in this module *)
  in
  match prj t v with None -> assert false | Some x -> x

let val_tag wit = val_tag (topwit wit)

let pr_argument_type arg =
  let Val.Dyn (tag, _) = arg in
  Val.pr tag

let safe_msgnl s =
  Proofview.NonLogical.catch
    (Proofview.NonLogical.print_debug (s++fnl()))
    (fun _ -> Proofview.NonLogical.print_warning (str "bug in the debugger: an exception is raised while printing debug information"++fnl()))

type value = Val.t

let push_appl appl args =
  match appl with
  | UnnamedAppl -> UnnamedAppl
  | GlbAppl l -> GlbAppl (List.map (fun (h,vs) -> (h,vs@args)) l)
let pr_generic arg =
    let Val.Dyn (tag, _) = arg in
    str"<" ++ Val.pr tag ++ str ":(" ++ Pptactic.pr_value Pptactic.ltop arg ++ str ")>"
let pr_appl h vs =
  Pptactic.pr_ltac_constant  h ++ spc () ++
  Pp.prlist_with_sep spc pr_generic vs
let rec name_with_list appl t =
  match appl with
  | [] -> t
  | (h,vs)::l -> Proofview.Trace.name_tactic (fun () -> pr_appl h vs) (name_with_list l t)
let name_if_glob appl t =
  match appl with
  | UnnamedAppl -> t
  | GlbAppl l -> name_with_list l t
let combine_appl appl1 appl2 =
  match appl1,appl2 with
  | UnnamedAppl,a | a,UnnamedAppl -> a
  | GlbAppl l1 , GlbAppl l2 -> GlbAppl (l2@l1)

let of_tacvalue v = in_gen (topwit wit_tacvalue) v
let to_tacvalue v = out_gen (topwit wit_tacvalue) v

(** More naming applications *)
let name_vfun appl vle =
  if has_type vle (topwit wit_tacvalue) then
    match to_tacvalue vle with
    | VFun (appl0,trace,lfun,vars,t) -> of_tacvalue (VFun (combine_appl appl0 appl,trace,lfun,vars,t))
    | _ -> vle
  else vle

module TacStore = Geninterp.TacStore

let f_avoid_ids : Id.Set.t TacStore.field = TacStore.field ()
(* ids inherited from the call context (needed to get fresh ids) *)
let f_debug : debug_info TacStore.field = TacStore.field ()
let f_trace : ltac_trace TacStore.field = TacStore.field ()

(* Signature for interpretation: val_interp and interpretation functions *)
type interp_sign = Geninterp.interp_sign = {
  lfun : value Id.Map.t;
  extra : TacStore.t }

let extract_trace ist = match TacStore.get ist.extra f_trace with
| None -> []
| Some l -> l

module Value = struct

  include Taccoerce.Value

  let of_closure ist tac =
    let closure = VFun (UnnamedAppl,extract_trace ist, ist.lfun, [], tac) in
    of_tacvalue closure

end

let print_top_val env v = Pptactic.pr_value Pptactic.ltop v

let catching_error call_trace fail (e, info) =
  let inner_trace =
    Option.default [] (Exninfo.get info ltac_trace_info)
  in
  if List.is_empty call_trace && List.is_empty inner_trace then fail (e, info)
  else begin
    assert (CErrors.noncritical e); (* preserved invariant *)
    let new_trace = inner_trace @ call_trace in
    let located_exc = (e, Exninfo.add info ltac_trace_info new_trace) in
    fail located_exc
  end

let catch_error call_trace f x =
  try f x
  with e when CErrors.noncritical e ->
    let e = CErrors.push e in
    catching_error call_trace iraise e

let catch_error_tac call_trace tac =
  Proofview.tclORELSE
    tac
    (catching_error call_trace (fun (e, info) -> Proofview.tclZERO ~info e))

let curr_debug ist = match TacStore.get ist.extra f_debug with
| None -> DebugOff
| Some level -> level

let pr_closure env ist body =
  let pp_body = Pptactic.pr_glob_tactic env body in
  let pr_sep () = fnl () in
  let pr_iarg (id, arg) =
    let arg = pr_argument_type arg in
    hov 0 (Id.print id ++ spc () ++ str ":" ++ spc () ++ arg)
  in
  let pp_iargs = v 0 (prlist_with_sep pr_sep pr_iarg (Id.Map.bindings ist)) in
  pp_body ++ fnl() ++ str "in environment " ++ fnl() ++ pp_iargs

let pr_inspect env expr result =
  let pp_expr = Pptactic.pr_glob_tactic env expr in
  let pp_result =
    if has_type result (topwit wit_tacvalue) then
    match to_tacvalue result with
    | VFun (_,_, ist, ul, b) ->
      let body = if List.is_empty ul then b else (TacFun (ul, b)) in
      str "a closure with body " ++ fnl() ++ pr_closure env ist body
    | VRec (ist, body) ->
      str "a recursive closure" ++ fnl () ++ pr_closure env !ist body
    else
      let pp_type = pr_argument_type result in
      str "an object of type" ++ spc () ++ pp_type
  in
  pp_expr ++ fnl() ++ str "this is " ++ pp_result

(* Transforms an id into a constr if possible, or fails with Not_found *)
let constr_of_id env id =
  EConstr.mkVar (let _ = Environ.lookup_named id env in id)

(** Generic arguments : table of interpretation functions *)

(* Some of the code further down depends on the fact that push_trace does not modify sigma (the evar map) *)
let push_trace call ist = match TacStore.get ist.extra f_trace with
| None -> Proofview.tclUNIT [call]
| Some trace -> Proofview.tclUNIT (call :: trace)

let propagate_trace ist loc id v =
  if has_type v (topwit wit_tacvalue) then
    let tacv = to_tacvalue v in
    match tacv with
    | VFun (appl,_,lfun,it,b) ->
        let t = if List.is_empty it then b else TacFun (it,b) in
        push_trace(loc,LtacVarCall (id,t)) ist >>= fun trace ->
        let ans = VFun (appl,trace,lfun,it,b) in
        Proofview.tclUNIT (of_tacvalue ans)
    | _ ->  Proofview.tclUNIT v
  else Proofview.tclUNIT v

let append_trace trace v =
  if has_type v (topwit wit_tacvalue) then
    match to_tacvalue v with
    | VFun (appl,trace',lfun,it,b) -> of_tacvalue (VFun (appl,trace'@trace,lfun,it,b))
    | _ -> v
  else v

(* Dynamically check that an argument is a tactic *)
let coerce_to_tactic loc id v =
  let fail () = user_err ?loc 
    (str "Variable " ++ Id.print id ++ str " should be bound to a tactic.")
  in
  if has_type v (topwit wit_tacvalue) then
    let tacv = to_tacvalue v in
    match tacv with
    | VFun _ -> v
    | _ -> fail ()
  else fail ()

let intro_pattern_of_ident id = make @@ IntroNaming (IntroIdentifier id)
let value_of_ident id =
  in_gen (topwit wit_intro_pattern) (intro_pattern_of_ident id)

let (+++) lfun1 lfun2 = Id.Map.fold Id.Map.add lfun1 lfun2

let extend_values_with_bindings (ln,lm) lfun =
  let of_cub c = match c with
  | [], c -> Value.of_constr c
  | _ -> in_gen (topwit wit_constr_under_binders) c
  in
  (* For compatibility, bound variables are visible only if no other
     binding of the same name exists *)
  let accu = Id.Map.map value_of_ident ln in
  let accu = lfun +++ accu in
  Id.Map.fold (fun id c accu -> Id.Map.add id (of_cub c) accu) lm accu

(***************************************************************************)
(* Evaluation/interpretation *)

let is_variable env id =
  Id.List.mem id (ids_of_named_context (Environ.named_context env))

(* Debug reference *)
let debug = ref DebugOff

(* Sets the debugger mode *)
let set_debug pos = debug := pos

(* Gives the state of debug *)
let get_debug () = !debug

let debugging_step ist pp = match curr_debug ist with
  | DebugOn lev ->
      safe_msgnl (str "Level " ++ int lev ++ str": " ++ pp () ++ fnl())
  | _ -> Proofview.NonLogical.return ()

let debugging_exception_step ist signal_anomaly e pp =
  let explain_exc =
    if signal_anomaly then explain_logic_error
    else explain_logic_error_no_anomaly in
  debugging_step ist (fun () ->
    pp() ++ spc() ++ str "raised the exception" ++ fnl() ++ explain_exc e)

(* Raise Not_found if not in interpretation sign *)
let try_interp_ltac_var coerce ist env {loc;v=id} =
  let v = Id.Map.find id ist.lfun in
  try coerce v with CannotCoerceTo s ->
    Taccoerce.error_ltac_variable ?loc id env v s

let interp_ltac_var coerce ist env locid =
  try try_interp_ltac_var coerce ist env locid
  with Not_found -> anomaly (str "Detected '" ++ Id.print locid.v ++ str "' as ltac var at interning time.")

let interp_ident ist env sigma id =
  try try_interp_ltac_var (coerce_var_to_ident false env sigma) ist (Some (env,sigma)) (make id)
  with Not_found -> id

(* Interprets an optional identifier, bound or fresh *)
let interp_name ist env sigma = function
  | Anonymous -> Anonymous
  | Name id -> Name (interp_ident ist env sigma id)

let interp_intro_pattern_var loc ist env sigma id =
  try try_interp_ltac_var (coerce_to_intro_pattern env sigma) ist (Some (env,sigma)) (make ?loc id)
  with Not_found -> IntroNaming (IntroIdentifier id)

let interp_intro_pattern_naming_var loc ist env sigma id =
  try try_interp_ltac_var (coerce_to_intro_pattern_naming env sigma) ist (Some (env,sigma)) (make ?loc id)
  with Not_found -> IntroIdentifier id

let interp_int ist ({loc;v=id} as locid) =
  try try_interp_ltac_var coerce_to_int ist None locid
  with Not_found ->
    user_err ?loc ~hdr:"interp_int"
     (str "Unbound variable "  ++ Id.print id ++ str".")

let interp_int_or_var ist = function
  | ArgVar locid -> interp_int ist locid
  | ArgArg n -> n

let interp_int_or_var_as_list ist = function
  | ArgVar ({v=id} as locid) ->
      (try coerce_to_int_or_var_list (Id.Map.find id ist.lfun)
       with Not_found | CannotCoerceTo _ -> [ArgArg (interp_int ist locid)])
  | ArgArg n as x -> [x]

let interp_int_or_var_list ist l =
  List.flatten (List.map (interp_int_or_var_as_list ist) l)

(* Interprets a bound variable (especially an existing hypothesis) *)
let interp_hyp ist env sigma ({loc;v=id} as locid) =
  (* Look first in lfun for a value coercible to a variable *)
  try try_interp_ltac_var (coerce_to_hyp env sigma) ist (Some (env,sigma)) locid
  with Not_found ->
  (* Then look if bound in the proof context at calling time *)
  if is_variable env id then id
  else Loc.raise ?loc (Logic.RefinerError (env, sigma, Logic.NoSuchHyp id))

let interp_hyp_list_as_list ist env sigma ({loc;v=id} as x) =
  try coerce_to_hyp_list env sigma (Id.Map.find id ist.lfun)
  with Not_found | CannotCoerceTo _ -> [interp_hyp ist env sigma x]

let interp_hyp_list ist env sigma l =
  List.flatten (List.map (interp_hyp_list_as_list ist env sigma) l)

let interp_reference ist env sigma = function
  | ArgArg (_,r) -> r
  | ArgVar {loc;v=id} ->
    try try_interp_ltac_var (coerce_to_reference env sigma) ist (Some (env,sigma)) (make ?loc id)
    with Not_found ->
      try
        VarRef (get_id (Environ.lookup_named id env))
      with Not_found -> error_global_not_found (make ?loc @@ qualid_of_ident id)

let try_interp_evaluable env (loc, id) =
  let v = Environ.lookup_named id env in
  match v with
  | LocalDef _ -> EvalVarRef id
  | _ -> error_not_evaluable (VarRef id)

let interp_evaluable ist env sigma = function
  | ArgArg (r,Some {loc;v=id}) ->
    (* Maybe [id] has been introduced by Intro-like tactics *)
    begin
      try try_interp_evaluable env (loc, id)
      with Not_found ->
        match r with
        | EvalConstRef _ -> r
        | _ -> error_global_not_found (make ?loc @@ qualid_of_ident id)
    end
  | ArgArg (r,None) -> r
  | ArgVar {loc;v=id} ->
    try try_interp_ltac_var (coerce_to_evaluable_ref env sigma) ist (Some (env,sigma)) (make ?loc id)
    with Not_found ->
      try try_interp_evaluable env (loc, id)
      with Not_found -> error_global_not_found (make ?loc @@ qualid_of_ident id)

(* Interprets an hypothesis name *)
let interp_occurrences ist occs =
  Locusops.occurrences_map (interp_int_or_var_list ist) occs

let interp_hyp_location ist env sigma ((occs,id),hl) =
  ((interp_occurrences ist occs,interp_hyp ist env sigma id),hl)

let interp_hyp_location_list_as_list ist env sigma ((occs,id),hl as x) =
  match occs,hl with
  | AllOccurrences,InHyp ->
      List.map (fun id -> ((AllOccurrences,id),InHyp))
        (interp_hyp_list_as_list ist env sigma id)
  | _,_ -> [interp_hyp_location ist env sigma x]

let interp_hyp_location_list ist env sigma l =
  List.flatten (List.map (interp_hyp_location_list_as_list ist env sigma) l)

let interp_clause ist env sigma { onhyps=ol; concl_occs=occs } : clause =
  { onhyps=Option.map (interp_hyp_location_list ist env sigma) ol;
    concl_occs=interp_occurrences ist occs }

(* Interpretation of constructions *)

(* Extract the constr list from lfun *)
let extract_ltac_constr_values ist env =
  let fold id v accu =
    try
      let c = coerce_to_constr env v in
      Id.Map.add id c accu
    with CannotCoerceTo _ -> accu
  in
  Id.Map.fold fold ist.lfun Id.Map.empty
(** ppedrot: I have changed the semantics here. Before this patch, closure was
    implemented as a list and a variable could be bound several times with
    different types, resulting in its possible appearance on both sides. This
    could barely be defined as a feature... *)

(* Extract the identifier list from lfun: join all branches (what to do else?)*)
let rec intropattern_ids accu {loc;v=pat} = match pat with
  | IntroNaming (IntroIdentifier id) -> Id.Set.add id accu
  | IntroAction (IntroOrAndPattern (IntroAndPattern l)) ->
      List.fold_left intropattern_ids accu l
  | IntroAction (IntroOrAndPattern (IntroOrPattern ll)) ->
      List.fold_left intropattern_ids accu (List.flatten ll)
  | IntroAction (IntroInjection l) ->
      List.fold_left intropattern_ids accu l
  | IntroAction (IntroApplyOn ({v=c},pat)) -> intropattern_ids accu pat
  | IntroNaming (IntroAnonymous | IntroFresh _)
  | IntroAction (IntroWildcard | IntroRewrite _)
  | IntroForthcoming _ -> accu

let extract_ids ids lfun accu =
  let fold id v accu =
    if has_type v (topwit wit_intro_pattern) then
      let {v=ipat} = out_gen (topwit wit_intro_pattern) v in
      if Id.List.mem id ids then accu
      else intropattern_ids accu (make ipat)
    else accu
  in
  Id.Map.fold fold lfun accu

let default_fresh_id = Id.of_string "H"

let interp_fresh_id ist env sigma l =
  let extract_ident ist env sigma id =
    try try_interp_ltac_var (coerce_to_ident_not_fresh env sigma)
                            ist (Some (env,sigma)) (make id)
    with Not_found -> id in
  let ids = List.map_filter (function ArgVar {v=id} -> Some id | _ -> None) l in
  let avoid = match TacStore.get ist.extra f_avoid_ids with
  | None -> Id.Set.empty
  | Some l -> l
  in
  let avoid = extract_ids ids ist.lfun avoid in
  let id =
    if List.is_empty l then default_fresh_id
    else
      let s =
	String.concat "" (List.map (function
	  | ArgArg s -> s
          | ArgVar {v=id} -> Id.to_string (extract_ident ist env sigma id)) l) in
      let s = if CLexer.is_keyword s then s^"0" else s in
      Id.of_string s in
  Tactics.fresh_id_in_env avoid id env

(* Extract the uconstr list from lfun *)
let extract_ltac_constr_context ist env sigma =
  let add_uconstr id v map =
    try Id.Map.add id (coerce_to_uconstr env v) map
    with CannotCoerceTo _ -> map
  in
  let add_constr id v map =
    try Id.Map.add id (coerce_to_constr env v) map
    with CannotCoerceTo _ -> map
  in
  let add_ident id v map =
    try Id.Map.add id (coerce_var_to_ident false env sigma v) map
    with CannotCoerceTo _ -> map
  in
  let fold id v {idents;typed;untyped} =
    let idents = add_ident id v idents in
    let typed = add_constr id v typed in
    let untyped = add_uconstr id v untyped in
    { idents ; typed ; untyped }
  in
  let empty =  { idents = Id.Map.empty ;typed = Id.Map.empty ; untyped = Id.Map.empty } in
  Id.Map.fold fold ist.lfun empty

(** Significantly simpler than [interp_constr], to interpret an
    untyped constr, it suffices to adjoin a closure environment. *)
let interp_glob_closure ist env sigma ?(kind=WithoutTypeConstraint) ?(pattern_mode=false) (term,term_expr_opt) =
  let closure = extract_ltac_constr_context ist env sigma in
  match term_expr_opt with
  | None -> { closure ; term }
  | Some term_expr ->
     (* If at toplevel (term_expr_opt<>None), the error can be due to
       an incorrect context at globalization time: we retype with the
       now known intros/lettac/inversion hypothesis names *)
      let constr_context =
        Id.Set.union
          (Id.Map.domain closure.typed)
          (Id.Map.domain closure.untyped)
      in
      let ltacvars = {
        ltac_vars = constr_context;
        ltac_bound = Id.Map.domain ist.lfun;
        ltac_extra = Genintern.Store.empty;
      } in
      { closure ; term = intern_gen kind ~pattern_mode ~ltacvars env sigma term_expr }

let interp_uconstr ist env sigma c = interp_glob_closure ist env sigma c

let interp_gen kind ist pattern_mode flags env sigma c =
  let kind_for_intern = match kind with OfType _ -> WithoutTypeConstraint | _ -> kind in
  let { closure = constrvars ; term } =
    interp_glob_closure ist env sigma ~kind:kind_for_intern ~pattern_mode c in
  let vars = {
    ltac_constrs = constrvars.typed;
    ltac_uconstrs = constrvars.untyped;
    ltac_idents = constrvars.idents;
    ltac_genargs = ist.lfun;
  } in
  (* Jason Gross: To avoid unnecessary modifications to tacinterp, as
      suggested by Arnaud Spiwack, we run push_trace immediately.  We do
      this with the kludge of an empty proofview, and rely on the
      invariant that running the tactic returned by push_trace does
      not modify sigma. *)
  let (_, dummy_proofview) = Proofview.init sigma [] in
  let (trace,_,_,_) = Proofview.apply env (push_trace (loc_of_glob_constr term,LtacConstrInterp (term,vars)) ist) dummy_proofview in
  let (evd,c) =
    catch_error trace (understand_ltac flags env sigma vars kind) term
  in
  (* spiwack: to avoid unnecessary modifications of tacinterp, as this
     function already use effect, I call [run] hoping it doesn't mess
     up with any assumption. *)
  Proofview.NonLogical.run (db_constr (curr_debug ist) env evd c);
  (evd,c)

let constr_flags () = {
  use_typeclasses = true;
  solve_unification_constraints = true;
  use_hook = Pfedit.solve_by_implicit_tactic ();
  fail_evar = true;
  expand_evars = true }

(* Interprets a constr; expects evars to be solved *)
let interp_constr_gen kind ist env sigma c =
  interp_gen kind ist false (constr_flags ()) env sigma c

let interp_constr = interp_constr_gen WithoutTypeConstraint

let interp_type = interp_constr_gen IsType

let open_constr_use_classes_flags () = {
  use_typeclasses = true;
  solve_unification_constraints = true;
  use_hook = Pfedit.solve_by_implicit_tactic ();
  fail_evar = false;
  expand_evars = true }

let open_constr_no_classes_flags () = {
  use_typeclasses = false;
  solve_unification_constraints = true;
  use_hook = Pfedit.solve_by_implicit_tactic ();
  fail_evar = false;
  expand_evars = true }

let pure_open_constr_flags = {
  use_typeclasses = false;
  solve_unification_constraints = true;
  use_hook = None;
  fail_evar = false;
  expand_evars = false }

(* Interprets an open constr *)
let interp_open_constr ?(expected_type=WithoutTypeConstraint) ?(flags=open_constr_no_classes_flags ()) ist env sigma c =
  interp_gen expected_type ist false flags env sigma c

let interp_open_constr_with_classes ?(expected_type=WithoutTypeConstraint) ist env sigma c =
  interp_gen expected_type ist false (open_constr_use_classes_flags ()) env sigma c

let interp_pure_open_constr ist =
  interp_gen WithoutTypeConstraint ist false pure_open_constr_flags

let interp_typed_pattern ist env sigma (_,c,_) =
  let sigma, c =
    interp_gen WithoutTypeConstraint ist true pure_open_constr_flags env sigma c in
  (** FIXME: it is necessary to be unsafe here because of the way we handle
      evars in the pretyper. Sometimes they get solved eagerly. *)
  pattern_of_constr env sigma (EConstr.Unsafe.to_constr c)

(* Interprets a constr expression *)
let interp_constr_in_compound_list inj_fun dest_fun interp_fun ist env sigma l =
  let try_expand_ltac_var sigma x =
    try match DAst.get (fst (dest_fun x)) with
    | GVar id ->
      let v = Id.Map.find id ist.lfun in
      sigma, List.map inj_fun (coerce_to_constr_list env v)
    | _ ->
        raise Not_found
    with CannotCoerceTo _ | Not_found ->
      (* dest_fun, List.assoc may raise Not_found *)
      let sigma, c = interp_fun ist env sigma x in
      sigma, [c] in
  let sigma, l = List.fold_left_map try_expand_ltac_var sigma l in
  sigma, List.flatten l

let interp_constr_list ist env sigma c =
  interp_constr_in_compound_list (fun x -> x) (fun x -> x) interp_constr ist env sigma c

let interp_open_constr_list =
  interp_constr_in_compound_list (fun x -> x) (fun x -> x) interp_open_constr

(* Interprets a reduction expression *)
let interp_unfold ist env sigma (occs,qid) =
  (interp_occurrences ist occs,interp_evaluable ist env sigma qid)

let interp_flag ist env sigma red =
  { red with rConst = List.map (interp_evaluable ist env sigma) red.rConst }

let interp_constr_with_occurrences ist env sigma (occs,c) =
  let (sigma,c_interp) = interp_constr ist env sigma c in
  sigma , (interp_occurrences ist occs, c_interp)

let interp_closed_typed_pattern_with_occurrences ist env sigma (occs, a) =
  let p = match a with
  | Inl (ArgVar {loc;v=id}) ->
      (* This is the encoding of an ltac var supposed to be bound
         prioritary to an evaluable reference and otherwise to a constr
         (it is an encoding to satisfy the "union" type given to Simpl) *)
    let coerce_eval_ref_or_constr x =
      try Inl (coerce_to_evaluable_ref env sigma x)
      with CannotCoerceTo _ ->
        let c = coerce_to_closed_constr env x in
        Inr (pattern_of_constr env sigma (EConstr.to_constr sigma c)) in
    (try try_interp_ltac_var coerce_eval_ref_or_constr ist (Some (env,sigma)) (make ?loc id)
     with Not_found ->
       error_global_not_found (make ?loc @@ qualid_of_ident id))
  | Inl (ArgArg _ as b) -> Inl (interp_evaluable ist env sigma b)
  | Inr c -> Inr (interp_typed_pattern ist env sigma c) in
  interp_occurrences ist occs, p

let interp_constr_with_occurrences_and_name_as_list =
  interp_constr_in_compound_list
    (fun c -> ((AllOccurrences,c),Anonymous))
    (function ((occs,c),Anonymous) when occs == AllOccurrences -> c
      | _ -> raise Not_found)
    (fun ist env sigma (occ_c,na) ->
      let (sigma,c_interp) = interp_constr_with_occurrences ist env sigma occ_c in
      sigma, (c_interp,
       interp_name ist env sigma na))

let interp_red_expr ist env sigma = function
  | Unfold l -> sigma , Unfold (List.map (interp_unfold ist env sigma) l)
  | Fold l ->
    let (sigma,l_interp) = interp_constr_list ist env sigma l in
    sigma , Fold l_interp
  | Cbv f -> sigma , Cbv (interp_flag ist env sigma f)
  | Cbn f -> sigma , Cbn (interp_flag ist env sigma f)
  | Lazy f -> sigma , Lazy (interp_flag ist env sigma f)
  | Pattern l ->
      let (sigma,l_interp) =
        Evd.MonadR.List.map_right
          (fun c sigma -> interp_constr_with_occurrences ist env sigma c) l sigma
      in
      sigma , Pattern l_interp
  | Simpl (f,o) ->
     sigma , Simpl (interp_flag ist env sigma f,
		    Option.map (interp_closed_typed_pattern_with_occurrences ist env sigma) o)
  | CbvVm o ->
    sigma , CbvVm (Option.map (interp_closed_typed_pattern_with_occurrences ist env sigma) o)
  | CbvNative o ->
    sigma , CbvNative (Option.map (interp_closed_typed_pattern_with_occurrences ist env sigma) o)
  | (Red _ |  Hnf | ExtraRedExpr _ as r) -> sigma , r

let interp_may_eval f ist env sigma = function
  | ConstrEval (r,c) ->
      let (sigma,redexp) = interp_red_expr ist env sigma r in
      let (sigma,c_interp) = f ist env sigma c in
      let (redfun, _) = Redexpr.reduction_of_red_expr env redexp in
      redfun env sigma c_interp
  | ConstrContext ({loc;v=s},c) ->
      (try
	let (sigma,ic) = f ist env sigma c in
	let ctxt = coerce_to_constr_context (Id.Map.find s ist.lfun) in
	let ctxt = EConstr.Unsafe.to_constr ctxt in
        let ic = EConstr.Unsafe.to_constr ic in
	let c = subst_meta [Constr_matching.special_meta,ic] ctxt in
        Typing.solve_evars env sigma (EConstr.of_constr c)
      with
	| Not_found ->
	    user_err ?loc ~hdr:"interp_may_eval"
	    (str "Unbound context identifier" ++ Id.print s ++ str"."))
  | ConstrTypeOf c ->
      let (sigma,c_interp) = f ist env sigma c in
      let (sigma, t) = Typing.type_of ~refresh:true env sigma c_interp in
      (sigma, t)
  | ConstrTerm c ->
     try
	f ist env sigma c
     with reraise ->
       let reraise = CErrors.push reraise in
       (* spiwack: to avoid unnecessary modifications of tacinterp, as this
          function already use effect, I call [run] hoping it doesn't mess
          up with any assumption. *)
       Proofview.NonLogical.run (debugging_exception_step ist false (fst reraise) (fun () ->
         str"interpretation of term " ++ pr_glob_constr_env env (fst c)));
       iraise reraise

(* Interprets a constr expression possibly to first evaluate *)
let interp_constr_may_eval ist env sigma c =
  let (sigma,csr) =
    try
      interp_may_eval interp_constr ist env sigma c
    with reraise ->
      let reraise = CErrors.push reraise in
      (* spiwack: to avoid unnecessary modifications of tacinterp, as this
          function already use effect, I call [run] hoping it doesn't mess
          up with any assumption. *)
       Proofview.NonLogical.run (debugging_exception_step ist false (fst reraise) (fun () -> str"evaluation of term"));
      iraise reraise
  in
  begin
    (* spiwack: to avoid unnecessary modifications of tacinterp, as this
       function already use effect, I call [run] hoping it doesn't mess
       up with any assumption. *)
    Proofview.NonLogical.run (db_constr (curr_debug ist) env sigma csr);
    sigma , csr
  end

(** TODO: should use dedicated printers *)
let message_of_value v =
  let pr_with_env pr =
    Ftactic.enter begin fun gl -> Ftactic.return (pr (pf_env gl) (project gl)) end in
  let open Genprint in
  match generic_val_print v with
  | TopPrinterBasic pr -> Ftactic.return (pr ())
  | TopPrinterNeedsContext pr -> pr_with_env pr
  | TopPrinterNeedsContextAndLevel { default_ensure_surrounded; printer } ->
     pr_with_env (fun env sigma -> printer env sigma default_ensure_surrounded)

let interp_message_token ist = function
  | MsgString s -> Ftactic.return (str s)
  | MsgInt n -> Ftactic.return (int n)
  | MsgIdent {loc;v=id} ->
    let v = try Some (Id.Map.find id ist.lfun) with Not_found -> None in
    match v with
    | None -> Ftactic.lift (Tacticals.New.tclZEROMSG (Id.print id ++ str" not found."))
    | Some v -> message_of_value v

let interp_message ist l =
  let open Ftactic in
  Ftactic.List.map (interp_message_token ist) l >>= fun l ->
  Ftactic.return (prlist_with_sep spc (fun x -> x) l)

let rec interp_intro_pattern ist env sigma = with_loc_val (fun ?loc -> function
  | IntroAction pat ->
    let (sigma,pat) = interp_intro_pattern_action ist env sigma pat in
    sigma, make ?loc @@ IntroAction pat
  | IntroNaming (IntroIdentifier id) ->
    sigma, make ?loc @@ interp_intro_pattern_var loc ist env sigma id
  | IntroNaming pat ->
    sigma, make ?loc @@ IntroNaming (interp_intro_pattern_naming loc ist env sigma pat)
  | IntroForthcoming _  as x -> sigma, make ?loc x)

and interp_intro_pattern_naming loc ist env sigma = function
  | IntroFresh id -> IntroFresh (interp_ident ist env sigma id)
  | IntroIdentifier id -> interp_intro_pattern_naming_var loc ist env sigma id
  | IntroAnonymous as x -> x

and interp_intro_pattern_action ist env sigma = function
  | IntroOrAndPattern l ->
      let (sigma,l) = interp_or_and_intro_pattern ist env sigma l in
      sigma, IntroOrAndPattern l
  | IntroInjection l ->
      let sigma,l = interp_intro_pattern_list_as_list ist env sigma l in
      sigma, IntroInjection l
  | IntroApplyOn ({loc;v=c},ipat) ->
      let c env sigma = interp_open_constr ist env sigma c in
      let sigma,ipat = interp_intro_pattern ist env sigma ipat in
      sigma, IntroApplyOn (make ?loc c,ipat)
  | IntroWildcard | IntroRewrite _ as x -> sigma, x

and interp_or_and_intro_pattern ist env sigma = function
  | IntroAndPattern l ->
      let sigma, l = List.fold_left_map (interp_intro_pattern ist env) sigma l in
      sigma, IntroAndPattern l
  | IntroOrPattern ll ->
      let sigma, ll = List.fold_left_map (interp_intro_pattern_list_as_list ist env) sigma ll in
      sigma, IntroOrPattern ll

and interp_intro_pattern_list_as_list ist env sigma = function
  | [{loc;v=IntroNaming (IntroIdentifier id)}] as l ->
      (try sigma, coerce_to_intro_pattern_list ?loc env sigma (Id.Map.find id ist.lfun)
       with Not_found | CannotCoerceTo _ ->
         List.fold_left_map (interp_intro_pattern ist env) sigma l)
  | l -> List.fold_left_map (interp_intro_pattern ist env) sigma l

let interp_intro_pattern_naming_option ist env sigma = function
  | None -> None
  | Some lpat -> Some (map_with_loc (fun ?loc pat -> interp_intro_pattern_naming loc ist env sigma pat) lpat)

let interp_or_and_intro_pattern_option ist env sigma = function
  | None -> sigma, None
  | Some (ArgVar {loc;v=id}) ->
      (match interp_intro_pattern_var loc ist env sigma id with
      | IntroAction (IntroOrAndPattern l) -> sigma, Some (make ?loc l)
      | _ ->
        user_err ?loc (str "Cannot coerce to a disjunctive/conjunctive pattern."))
  | Some (ArgArg {loc;v=l}) ->
      let sigma,l = interp_or_and_intro_pattern ist env sigma l in
      sigma, Some (make ?loc l)

let interp_intro_pattern_option ist env sigma = function
  | None -> sigma, None
  | Some ipat ->
      let sigma, ipat = interp_intro_pattern ist env sigma ipat in
      sigma, Some ipat

let interp_in_hyp_as ist env sigma (id,ipat) =
  let sigma, ipat = interp_intro_pattern_option ist env sigma ipat in
  sigma,(interp_hyp ist env sigma id,ipat)

let interp_binding_name ist env sigma = function
  | AnonHyp n -> AnonHyp n
  | NamedHyp id ->
      (* If a name is bound, it has to be a quantified hypothesis *)
      (* user has to use other names for variables if these ones clash with *)
      (* a name intented to be used as a (non-variable) identifier *)
      try try_interp_ltac_var (coerce_to_quantified_hypothesis sigma) ist (Some (env,sigma)) (make id)
      with Not_found -> NamedHyp id

let interp_declared_or_quantified_hypothesis ist env sigma = function
  | AnonHyp n -> AnonHyp n
  | NamedHyp id ->
      try try_interp_ltac_var
            (coerce_to_decl_or_quant_hyp env sigma) ist (Some (env,sigma)) (make id)
      with Not_found -> NamedHyp id

let interp_binding ist env sigma {loc;v=(b,c)} =
  let sigma, c = interp_open_constr ist env sigma c in
  sigma, (make ?loc (interp_binding_name ist env sigma b,c))

let interp_bindings ist env sigma = function
| NoBindings ->
    sigma, NoBindings
| ImplicitBindings l ->
    let sigma, l = interp_open_constr_list ist env sigma l in
    sigma, ImplicitBindings l
| ExplicitBindings l ->
    let sigma, l = List.fold_left_map (interp_binding ist env) sigma l in
    sigma, ExplicitBindings l

let interp_constr_with_bindings ist env sigma (c,bl) =
  let sigma, bl = interp_bindings ist env sigma bl in
  let sigma, c = interp_constr ist env sigma c in
  sigma, (c,bl)

let interp_open_constr_with_bindings ist env sigma (c,bl) =
  let sigma, bl = interp_bindings ist env sigma bl in
  let sigma, c = interp_open_constr ist env sigma c in
  sigma, (c, bl)

let loc_of_bindings = function
| NoBindings         -> None
| ImplicitBindings l -> loc_of_glob_constr (fst (List.last l))
| ExplicitBindings l -> (List.last l).loc

let interp_open_constr_with_bindings_loc ist ((c,_),bl as cb) =
  let loc1 = loc_of_glob_constr c in
  let loc2 = loc_of_bindings bl in
  let loc  = Loc.merge_opt loc1 loc2 in
  let f env sigma = interp_open_constr_with_bindings ist env sigma cb in
  (loc,f)

let interp_destruction_arg ist gl arg =
  match arg with
  | keep,ElimOnConstr c ->
      keep,ElimOnConstr begin fun env sigma ->
        interp_open_constr_with_bindings ist env sigma c
      end
  | keep,ElimOnAnonHyp n as x -> x
  | keep,ElimOnIdent {loc;v=id} ->
      let error () = user_err ?loc 
       (strbrk "Cannot coerce " ++ Id.print id ++
        strbrk " neither to a quantified hypothesis nor to a term.")
      in
      let try_cast_id id' =
        if Tactics.is_quantified_hypothesis id' gl
        then keep,ElimOnIdent (make ?loc id')
        else
          (keep, ElimOnConstr begin fun env sigma ->
          try (sigma, (constr_of_id env id', NoBindings))
          with Not_found ->
            user_err ?loc  ~hdr:"interp_destruction_arg" (
            Id.print id ++ strbrk " binds to " ++ Id.print id' ++ strbrk " which is neither a declared nor a quantified hypothesis.")
          end)
      in
      try
        (** FIXME: should be moved to taccoerce *)
        let v = Id.Map.find id ist.lfun in
        if has_type v (topwit wit_intro_pattern) then
          let v = out_gen (topwit wit_intro_pattern) v in
          match v with
          | {v=IntroNaming (IntroIdentifier id)} -> try_cast_id id
          | _ -> error ()
        else if has_type v (topwit wit_var) then
          let id = out_gen (topwit wit_var) v in
          try_cast_id id
        else if has_type v (topwit wit_int) then
          keep,ElimOnAnonHyp (out_gen (topwit wit_int) v)
        else match Value.to_constr v with
        | None -> error ()
        | Some c -> keep,ElimOnConstr (fun env sigma -> (sigma, (c,NoBindings)))
      with Not_found ->
	(* We were in non strict (interactive) mode *)
	if Tactics.is_quantified_hypothesis id gl then
          keep,ElimOnIdent (make ?loc id)
	else
          let c = (DAst.make ?loc @@ GVar id,Some (make @@ CRef (make ?loc @@ Ident id,None))) in
          let f env sigma =
            let (sigma,c) = interp_open_constr ist env sigma c in
            (sigma, (c,NoBindings))
          in
          keep,ElimOnConstr f

(* Associates variables with values and gives the remaining variables and
   values *)
let head_with_value (lvar,lval) =
  let rec head_with_value_rec lacc = function
    | ([],[]) -> (lacc,[],[])
    | (vr::tvr,ve::tve) ->
      (match vr with
      |	Anonymous -> head_with_value_rec lacc (tvr,tve)
      | Name v -> head_with_value_rec ((v,ve)::lacc) (tvr,tve))
    | (vr,[]) -> (lacc,vr,[])
    | ([],ve) -> (lacc,[],ve)
  in
  head_with_value_rec [] (lvar,lval)

(** [interp_context ctxt] interprets a context (as in
    {!Matching.matching_result}) into a context value of Ltac.  *)
let interp_context ctxt = in_gen (topwit wit_constr_context) ctxt

(* Reads a pattern by substituting vars of lfun *)
let use_types = false

let eval_pattern lfun ist env sigma (bvars,(glob,_),pat as c) =
  if use_types then
    (bvars,interp_typed_pattern ist env sigma c)
  else
    (bvars,instantiate_pattern env sigma lfun pat)

let read_pattern lfun ist env sigma = function
  | Subterm (ido,c) -> Subterm (ido,eval_pattern lfun ist env sigma c)
  | Term c -> Term (eval_pattern lfun ist env sigma c)

(* Reads the hypotheses of a Match Context rule *)
let cons_and_check_name id l =
  if Id.List.mem id l then
    user_err ~hdr:"read_match_goal_hyps" (
      str "Hypothesis pattern-matching variable " ++ Id.print id ++
      str " used twice in the same pattern.")
  else id::l

let rec read_match_goal_hyps lfun ist env sigma lidh = function
  | (Hyp ({loc;v=na} as locna,mp))::tl ->
      let lidh' = Name.fold_right cons_and_check_name na lidh in
      Hyp (locna,read_pattern lfun ist env sigma mp)::
	(read_match_goal_hyps lfun ist env sigma lidh' tl)
  | (Def ({loc;v=na} as locna,mv,mp))::tl ->
      let lidh' = Name.fold_right cons_and_check_name na lidh in
      Def (locna,read_pattern lfun ist env sigma mv, read_pattern lfun ist env sigma mp)::
	(read_match_goal_hyps lfun ist env sigma lidh' tl)
  | [] -> []

(* Reads the rules of a Match Context or a Match *)
let rec read_match_rule lfun ist env sigma = function
  | (All tc)::tl -> (All tc)::(read_match_rule lfun ist env sigma tl)
  | (Pat (rl,mp,tc))::tl ->
      Pat (read_match_goal_hyps lfun ist env sigma [] rl, read_pattern lfun ist env sigma mp,tc)
      :: read_match_rule lfun ist env sigma tl
  | [] -> []

(* Fully evaluate an untyped constr *)
let type_uconstr ?(flags = {(constr_flags ()) with use_hook = None })
  ?(expected_type = WithoutTypeConstraint) ist c =
  begin fun env sigma ->
  let { closure; term } = c in
  let vars = {
    ltac_constrs = closure.typed;
    ltac_uconstrs = closure.untyped;
    ltac_idents = closure.idents;
    ltac_genargs = Id.Map.empty;
  } in
  understand_ltac flags env sigma vars expected_type term
  end

let warn_deprecated_info =
  CWarnings.create ~name:"deprecated-info-tactical" ~category:"deprecated"
         (fun () ->
          strbrk "The general \"info\" tactic is currently not working." ++ spc()++
            strbrk "There is an \"Info\" command to replace it." ++fnl () ++
            strbrk "Some specific verbose tactics may also exist, such as info_eauto.")

(* Interprets an l-tac expression into a value *)
let rec val_interp ist ?(appl=UnnamedAppl) (tac:glob_tactic_expr) : Val.t Ftactic.t =
  (* The name [appl] of applied top-level Ltac names is ignored in
     [value_interp]. It is installed in the second step by a call to
     [name_vfun], because it gives more opportunities to detect a
     [VFun]. Otherwise a [Ltac t := let x := .. in tac] would never
     register its name since it is syntactically a let, not a
     function.  *)
  let value_interp ist = match tac with
  | TacFun (it, body) ->
    Ftactic.return (of_tacvalue (VFun (UnnamedAppl,extract_trace ist, ist.lfun, it, body)))
  | TacLetIn (true,l,u) -> interp_letrec ist l u
  | TacLetIn (false,l,u) -> interp_letin ist l u
  | TacMatchGoal (lz,lr,lmr) -> interp_match_goal ist lz lr lmr
  | TacMatch (lz,c,lmr) -> interp_match ist lz c lmr
  | TacArg (loc,a) -> interp_tacarg ist a
  | t ->
    (** Delayed evaluation *)
    Ftactic.return (of_tacvalue (VFun (UnnamedAppl,extract_trace ist, ist.lfun, [], t)))
  in
  let open Ftactic in
  Control.check_for_interrupt ();
  match curr_debug ist with
  | DebugOn lev ->
        let eval v =
          let ist = { ist with extra = TacStore.set ist.extra f_debug v } in
          value_interp ist >>= fun v -> return (name_vfun appl v)
        in
	Tactic_debug.debug_prompt lev tac eval
  | _ -> value_interp ist >>= fun v -> return (name_vfun appl v)


and eval_tactic ist tac : unit Proofview.tactic = match tac with
  | TacAtom (loc,t) ->
      let call = LtacAtomCall t in
      push_trace(loc,call) ist >>= fun trace ->
      Profile_ltac.do_profile "eval_tactic:2" trace
        (catch_error_tac trace (interp_atomic ist t))
  | TacFun _ | TacLetIn _ | TacMatchGoal _ | TacMatch _ -> interp_tactic ist tac
  | TacId [] -> Proofview.tclLIFT (db_breakpoint (curr_debug ist) [])
  | TacId s ->
      let msgnl =
        let open Ftactic in
        interp_message ist s >>= fun msg ->
        return (hov 0 msg , hov 0 msg)
      in
      let print (_,msgnl) = Proofview.(tclLIFT (NonLogical.print_info msgnl)) in
      let log (msg,_) = Proofview.Trace.log (fun () -> msg) in
      let break = Proofview.tclLIFT (db_breakpoint (curr_debug ist) s) in
      Ftactic.run msgnl begin fun msgnl ->
        print msgnl <*> log msgnl <*> break
      end
  | TacFail (g,n,s) ->
      let msg = interp_message ist s in
      let tac l = Tacticals.New.tclFAIL (interp_int_or_var ist n) l in
      let tac =
        match g with
        | TacLocal -> fun l -> Proofview.tclINDEPENDENT (tac l)
        | TacGlobal -> tac
      in
      Ftactic.run msg tac
  | TacProgress tac -> Tacticals.New.tclPROGRESS (interp_tactic ist tac)
  | TacShowHyps tac ->
         Proofview.V82.tactic begin
           tclSHOWHYPS (Proofview.V82.of_tactic (interp_tactic ist tac))
         end
  | TacAbstract (t,ido) ->
      let call = LtacMLCall tac in
      push_trace(None,call) ist >>= fun trace ->
      Profile_ltac.do_profile "eval_tactic:TacAbstract" trace
        (catch_error_tac trace begin
      Proofview.Goal.enter begin fun gl -> Tactics.tclABSTRACT
        (Option.map (interp_ident ist (pf_env gl) (project gl)) ido) (interp_tactic ist t)
      end end)
  | TacThen (t1,t) ->
      Tacticals.New.tclTHEN (interp_tactic ist t1) (interp_tactic ist t)
  | TacDispatch tl ->
      Proofview.tclDISPATCH (List.map (interp_tactic ist) tl)
  | TacExtendTac (tf,t,tl) ->
      Proofview.tclEXTEND (Array.map_to_list (interp_tactic ist) tf)
                          (interp_tactic ist t)
                          (Array.map_to_list (interp_tactic ist) tl)
  | TacThens (t1,tl) -> Tacticals.New.tclTHENS (interp_tactic ist t1) (List.map (interp_tactic ist) tl)
  | TacThens3parts (t1,tf,t,tl) ->
      Tacticals.New.tclTHENS3PARTS (interp_tactic ist t1)
	(Array.map (interp_tactic ist) tf) (interp_tactic ist t) (Array.map (interp_tactic ist) tl)
  | TacDo (n,tac) -> Tacticals.New.tclDO (interp_int_or_var ist n) (interp_tactic ist tac)
  | TacTimeout (n,tac) -> Tacticals.New.tclTIMEOUT (interp_int_or_var ist n) (interp_tactic ist tac)
  | TacTime (s,tac) -> Tacticals.New.tclTIME s (interp_tactic ist tac)
  | TacTry tac -> Tacticals.New.tclTRY (interp_tactic ist tac)
  | TacRepeat tac -> Tacticals.New.tclREPEAT (interp_tactic ist tac)
  | TacOr (tac1,tac2) ->
      Tacticals.New.tclOR (interp_tactic ist tac1) (interp_tactic ist tac2)
  | TacOnce tac ->
      Tacticals.New.tclONCE (interp_tactic ist tac)
  | TacExactlyOnce tac ->
      Tacticals.New.tclEXACTLY_ONCE (interp_tactic ist tac)
  | TacIfThenCatch (t,tt,te) ->
      Tacticals.New.tclIFCATCH
        (interp_tactic ist t)
        (fun () -> interp_tactic ist tt)
        (fun () -> interp_tactic ist te)
  | TacOrelse (tac1,tac2) ->
      Tacticals.New.tclORELSE (interp_tactic ist tac1) (interp_tactic ist tac2)
  | TacFirst l -> Tacticals.New.tclFIRST (List.map (interp_tactic ist) l)
  | TacSolve l -> Tacticals.New.tclSOLVE (List.map (interp_tactic ist) l)
  | TacComplete tac -> Tacticals.New.tclCOMPLETE (interp_tactic ist tac)
  | TacArg a -> interp_tactic ist (TacArg a)
  | TacInfo tac ->
      warn_deprecated_info ();
      eval_tactic ist tac
  | TacSelect (sel, tac) -> Tacticals.New.tclSELECT sel (interp_tactic ist tac)
  (* For extensions *)
  | TacAlias (loc,(s,l)) ->
      let (ids, body) = Tacenv.interp_alias s in
      let (>>=) = Ftactic.bind in
      let interp_vars = Ftactic.List.map (fun v -> interp_tacarg ist v) l in
      let tac l =
        let addvar x v accu = Id.Map.add x v accu in
        let lfun = List.fold_right2 addvar ids l ist.lfun in
        Ftactic.lift (push_trace (loc,LtacNotationCall s) ist) >>= fun trace ->
        let ist = {
          lfun = lfun;
          extra = TacStore.set ist.extra f_trace trace; } in
        val_interp ist body >>= fun v ->
        Ftactic.lift (tactic_of_value ist v)
      in
      let tac =
        Ftactic.with_env interp_vars >>= fun (env, lr) ->
        let name () = Pptactic.pr_alias (fun v -> print_top_val env v) 0 s lr in
        Proofview.Trace.name_tactic name (tac lr)
      (* spiwack: this use of name_tactic is not robust to a
         change of implementation of [Ftactic]. In such a situation,
         some more elaborate solution will have to be used. *)
      in
      let tac =
        let len1 = List.length ids in
        let len2 = List.length l in
        if len1 = len2 then tac
        else Tacticals.New.tclZEROMSG (str "Arguments length mismatch: \
          expected " ++ int len1 ++ str ", found " ++ int len2)
      in
      Ftactic.run tac (fun () -> Proofview.tclUNIT ())

  | TacML (loc,(opn,l)) ->
      push_trace (Loc.tag ?loc @@ LtacMLCall tac) ist >>= fun trace ->
      let ist = { ist with extra = TacStore.set ist.extra f_trace trace; } in
      let tac = Tacenv.interp_ml_tactic opn in
      let args = Ftactic.List.map_right (fun a -> interp_tacarg ist a) l in
      let tac args =
        let name () = Pptactic.pr_extend (fun v -> print_top_val () v) 0 opn args in
        Proofview.Trace.name_tactic name (catch_error_tac trace (tac args ist))
      in
      Ftactic.run args tac

and force_vrec ist v : Val.t Ftactic.t =
  if has_type v (topwit wit_tacvalue) then
    let v = to_tacvalue v in
    match v with
    | VRec (lfun,body) -> val_interp {ist with lfun = !lfun} body
    | v -> Ftactic.return (of_tacvalue v)
  else Ftactic.return v

and interp_ltac_reference ?loc' mustbetac ist r : Val.t Ftactic.t =
  match r with
  | ArgVar {loc;v=id} ->
      let v =
        try Id.Map.find id ist.lfun
        with Not_found -> in_gen (topwit wit_var) id
      in
      let open Ftactic in
      force_vrec ist v >>= begin fun v ->
      Ftactic.lift (propagate_trace ist loc id v) >>= fun v ->
      if mustbetac then Ftactic.return (coerce_to_tactic loc id v) else Ftactic.return v
      end
  | ArgArg (loc,r) ->
      let ids = extract_ids [] ist.lfun Id.Set.empty in
      let loc_info = (Option.default loc loc',LtacNameCall r) in
      let extra = TacStore.set ist.extra f_avoid_ids ids in
      push_trace loc_info ist >>= fun trace ->
      let extra = TacStore.set extra f_trace trace in
      let ist = { lfun = Id.Map.empty; extra = extra; } in
      let appl = GlbAppl[r,[]] in
      Profile_ltac.do_profile "interp_ltac_reference" trace ~count_call:false
        (val_interp ~appl ist (Tacenv.interp_ltac r))

and interp_tacarg ist arg : Val.t Ftactic.t =
  match arg with
  | TacGeneric arg -> interp_genarg ist arg
  | Reference r -> interp_ltac_reference false ist r
  | ConstrMayEval c ->
      Ftactic.enter begin fun gl ->
        let sigma = project gl in
        let env = Proofview.Goal.env gl in
        let (sigma,c_interp) = interp_constr_may_eval ist env sigma c in
        Proofview.tclTHEN (Proofview.Unsafe.tclEVARS sigma)
        (Ftactic.return (Value.of_constr c_interp))
      end
  | TacCall (loc,(r,[])) ->
      interp_ltac_reference true ist r
  | TacCall (loc,(f,l)) ->
      let (>>=) = Ftactic.bind in
      interp_ltac_reference true ist f >>= fun fv ->
      Ftactic.List.map (fun a -> interp_tacarg ist a) l >>= fun largs ->
      interp_app loc ist fv largs
  | TacFreshId l ->
      Ftactic.enter begin fun gl ->
        let id = interp_fresh_id ist (pf_env gl) (project gl) l in
        Ftactic.return (in_gen (topwit wit_intro_pattern) (make @@ IntroNaming (IntroIdentifier id)))
      end
  | TacPretype c ->
      Ftactic.enter begin fun gl ->
        let sigma = Proofview.Goal.sigma gl in
        let env = Proofview.Goal.env gl in
        let c = interp_uconstr ist env sigma c in
        let (sigma, c) = type_uconstr ist c env sigma in
        Proofview.tclTHEN (Proofview.Unsafe.tclEVARS sigma)
        (Ftactic.return (Value.of_constr c))
      end
  | TacNumgoals ->
      Ftactic.lift begin
        let open Proofview.Notations in
        Proofview.numgoals >>= fun i ->
        Proofview.tclUNIT (Value.of_int i)
      end
  | Tacexp t -> val_interp ist t

(* Interprets an application node *)
and interp_app loc ist fv largs : Val.t Ftactic.t =
  let (>>=) = Ftactic.bind in
  let fail = Tacticals.New.tclZEROMSG (str "Illegal tactic application.") in
  if has_type fv (topwit wit_tacvalue) then
  match to_tacvalue fv with
     (* if var=[] and body has been delayed by val_interp, then body
         is not a tactic that expects arguments.
         Otherwise Ltac goes into an infinite loop (val_interp puts
         a VFun back on body, and then interp_app is called again...) *)
    | (VFun(appl,trace,olfun,(_::_ as var),body)
      |VFun(appl,trace,olfun,([] as var),
         (TacFun _|TacLetIn _|TacMatchGoal _|TacMatch _| TacArg _ as body))) ->
	let (extfun,lvar,lval)=head_with_value (var,largs) in
        let fold accu (id, v) = Id.Map.add id v accu in
	let newlfun = List.fold_left fold olfun extfun in
      if List.is_empty lvar then
        begin Proofview.tclORELSE
            begin
              let ist = {
                lfun = newlfun;
                extra = TacStore.set ist.extra f_trace []; } in
              Profile_ltac.do_profile "interp_app" trace ~count_call:false
                (catch_error_tac trace (val_interp ist body)) >>= fun v ->
              Ftactic.return (name_vfun (push_appl appl largs) v)
            end
	    begin fun (e, info) ->
              Proofview.tclLIFT (debugging_exception_step ist false e (fun () -> str "evaluation")) <*>
	      Proofview.tclZERO ~info e
            end
        end >>= fun v ->
        (* No errors happened, we propagate the trace *)
        let v = append_trace trace v in
        let call_debug env =
          Proofview.tclLIFT (debugging_step ist (fun () -> str"evaluation returns"++fnl()++pr_value env v)) in
        begin
          let open Genprint in
          match generic_val_print v with
          | TopPrinterBasic _ -> call_debug None
          | TopPrinterNeedsContext _ | TopPrinterNeedsContextAndLevel _ ->
             Proofview.Goal.enter (fun gl -> call_debug (Some (pf_env gl,project gl)))
        end <*>
        if List.is_empty lval then Ftactic.return v else interp_app loc ist v lval
      else
        Ftactic.return (of_tacvalue (VFun(push_appl appl largs,trace,newlfun,lvar,body)))
    | (VFun(appl,trace,olfun,[],body)) ->
      let extra_args = List.length largs in
      Tacticals.New.tclZEROMSG (str "Illegal tactic application: got " ++
                                str (string_of_int extra_args) ++
                                str " extra " ++ str (String.plural extra_args "argument") ++
                                str ".")
    | VRec(_,_) -> fail
  else fail

(* Gives the tactic corresponding to the tactic value *)
and tactic_of_value ist vle =
  if has_type vle (topwit wit_tacvalue) then
  match to_tacvalue vle with
  | VFun (appl,trace,lfun,[],t) ->
      let ist = {
        lfun = lfun;
        extra = TacStore.set ist.extra f_trace []; } in
      let tac = name_if_glob appl (eval_tactic ist t) in
      Profile_ltac.do_profile "tactic_of_value" trace (catch_error_tac trace tac)
  | VFun (appl,_,vmap,vars,_) ->
     let tactic_nm =
       match appl with
         UnnamedAppl -> "An unnamed user-defined tactic"
       | GlbAppl apps ->
          let nms = List.map (fun (kn,_) -> Names.KerName.to_string kn) apps in
          match nms with
            []    -> assert false
          | kn::_ -> "The user-defined tactic \"" ^ kn ^ "\"" (* TODO: when do we not have a singleton? *)
     in
     let numargs = List.length vars in
     let givenargs =
       List.map (fun (arg,_) -> Names.Id.to_string arg) (Names.Id.Map.bindings vmap) in
     let numgiven = List.length givenargs in
     Tacticals.New.tclZEROMSG
       (Pp.str tactic_nm ++ Pp.str " was not fully applied:" ++ spc() ++
          (match numargs with
            0 -> assert false
          | 1 ->
             Pp.str "There is a missing argument for variable " ++
               (Name.print (List.hd vars))
          | _ -> Pp.str "There are missing arguments for variables " ++
             pr_enum Name.print vars) ++ Pp.pr_comma () ++
          match numgiven with
            0 ->
              Pp.str "no arguments at all were provided."
          | 1 ->
             Pp.str "an argument was provided for variable " ++
               Pp.str (List.hd givenargs) ++ Pp.str "."
          | _ ->
             Pp.str "arguments were provided for variables " ++
               pr_enum Pp.str givenargs ++ Pp.str ".")
  | VRec _ -> Tacticals.New.tclZEROMSG (str "A fully applied tactic is expected.")
  else if has_type vle (topwit wit_tactic) then
    let tac = out_gen (topwit wit_tactic) vle in
    tactic_of_value ist tac
  else Tacticals.New.tclZEROMSG (str "Expression does not evaluate to a tactic.")

(* Interprets the clauses of a recursive LetIn *)
and interp_letrec ist llc u =
  Proofview.tclUNIT () >>= fun () -> (* delay for the effects of [lref], just in case. *)
  let lref = ref ist.lfun in
  let fold accu ({v=na}, b) =
    let v = of_tacvalue (VRec (lref, TacArg (Loc.tag b))) in
    Name.fold_right (fun id -> Id.Map.add id v) na accu
  in
  let lfun = List.fold_left fold ist.lfun llc in
  let () = lref := lfun in
  let ist = { ist with lfun } in
  val_interp ist u

(* Interprets the clauses of a LetIn *)
and interp_letin ist llc u =
  let rec fold lfun = function
  | [] ->
    let ist = { ist with lfun } in
    val_interp ist u
  | ({v=na}, body) :: defs ->
    Ftactic.bind (interp_tacarg ist body) (fun v ->
    fold (Name.fold_right (fun id -> Id.Map.add id v) na lfun) defs)
  in
  fold ist.lfun llc

(** [interp_match_success lz ist succ] interprets a single matching success
    (of type {!Tactic_matching.t}). *)
and interp_match_success ist { Tactic_matching.subst ; context ; terms ; lhs } =
  let (>>=) = Ftactic.bind in
  let lctxt = Id.Map.map interp_context context in
  let hyp_subst = Id.Map.map Value.of_constr terms in
  let lfun = extend_values_with_bindings subst (lctxt +++ hyp_subst +++ ist.lfun) in
  let ist = { ist with lfun } in
  val_interp ist lhs >>= fun v ->
  if has_type v (topwit wit_tacvalue) then match to_tacvalue v with
  | VFun (appl,trace,lfun,[],t) ->
      let ist = {
        lfun = lfun;
        extra = TacStore.set ist.extra f_trace trace; } in
      let tac = eval_tactic ist t in
      let dummy = VFun (appl,extract_trace ist, Id.Map.empty, [], TacId []) in
      catch_error_tac trace (tac <*> Ftactic.return (of_tacvalue dummy))
  | _ -> Ftactic.return v
  else Ftactic.return v


(** [interp_match_successes lz ist s] interprets the stream of
    matching of successes [s]. If [lz] is set to true, then only the
    first success is considered, otherwise further successes are tried
    if the left-hand side fails. *)
and interp_match_successes lz ist s =
   let general =
     let break (e, info) = match e with
       | FailError (0, _) -> None
       | FailError (n, s) -> Some (FailError (pred n, s), info)
       | _ -> None
     in
     Proofview.tclBREAK break s >>= fun ans -> interp_match_success ist ans
   in
    match lz with
    | General ->
        general
    | Select ->
      begin
        (** Only keep the first matching result, we don't backtrack on it *)
        let s = Proofview.tclONCE s in
        s >>= fun ans -> interp_match_success ist ans
      end
    | Once ->
        (** Once a tactic has succeeded, do not backtrack anymore *)
        Proofview.tclONCE general

(* Interprets the Match expressions *)
and interp_match ist lz constr lmr =
  let (>>=) = Ftactic.bind in
  begin Proofview.tclORELSE
    (interp_ltac_constr ist constr)
    begin function
      | (e, info) ->
          Proofview.tclLIFT (debugging_exception_step ist true e
          (fun () -> str "evaluation of the matched expression")) <*>
          Proofview.tclZERO ~info e
    end
  end >>= fun constr ->
  Ftactic.enter begin fun gl ->
    let sigma = project gl in
    let env = Proofview.Goal.env gl in
    let ilr = read_match_rule (extract_ltac_constr_values ist env) ist env sigma lmr in
    interp_match_successes lz ist (Tactic_matching.match_term env sigma constr ilr)
  end

(* Interprets the Match Context expressions *)
and interp_match_goal ist lz lr lmr =
    Ftactic.enter begin fun gl ->
      let sigma = project gl in
      let env = Proofview.Goal.env gl in
      let hyps = Proofview.Goal.hyps gl in
      let hyps = if lr then List.rev hyps else hyps in
      let concl = Proofview.Goal.concl gl in
      let ilr = read_match_rule (extract_ltac_constr_values ist env) ist env sigma lmr in
      interp_match_successes lz ist (Tactic_matching.match_goal env sigma hyps concl ilr)
    end

(* Interprets extended tactic generic arguments *)
and interp_genarg ist x : Val.t Ftactic.t =
    let open Ftactic.Notations in
    (** Ad-hoc handling of some types. *)
    let tag = genarg_tag x in
    if argument_type_eq tag (unquote (topwit (wit_list wit_var))) then
      interp_genarg_var_list ist x
    else if argument_type_eq tag (unquote (topwit (wit_list wit_constr))) then
      interp_genarg_constr_list ist x
    else
    let GenArg (Glbwit wit, x) = x in
    match wit with
    | ListArg wit ->
      let map x = interp_genarg ist (Genarg.in_gen (glbwit wit) x) in
      Ftactic.List.map map x >>= fun l ->
      Ftactic.return (Val.Dyn (Val.typ_list, l))
    | OptArg wit ->
      begin match x with
      | None -> Ftactic.return (Val.Dyn (Val.typ_opt, None))
      | Some x ->
        interp_genarg ist (Genarg.in_gen (glbwit wit) x) >>= fun x ->
        Ftactic.return (Val.Dyn (Val.typ_opt, Some x))
      end
    | PairArg (wit1, wit2) ->
      let (p, q) = x in
      interp_genarg ist (Genarg.in_gen (glbwit wit1) p) >>= fun p ->
      interp_genarg ist (Genarg.in_gen (glbwit wit2) q) >>= fun q ->
      Ftactic.return (Val.Dyn (Val.typ_pair, (p, q)))
    | ExtraArg s ->
      Geninterp.interp wit ist x

(** returns [true] for genargs which have the same meaning
    independently of goals. *)

and interp_genarg_constr_list ist x =
  Ftactic.nf_enter begin fun gl ->
  let env = Proofview.Goal.env gl in
  let sigma = Proofview.Goal.sigma gl in
  let lc = Genarg.out_gen (glbwit (wit_list wit_constr)) x in
  let (sigma,lc) = interp_constr_list ist env sigma lc in
  let lc = in_list (val_tag wit_constr) lc in
  Proofview.tclTHEN (Proofview.Unsafe.tclEVARS sigma)
  (Ftactic.return lc)
  end

and interp_genarg_var_list ist x =
  Ftactic.enter begin fun gl ->
  let env = Proofview.Goal.env gl in
  let sigma = Proofview.Goal.sigma gl in
  let lc = Genarg.out_gen (glbwit (wit_list wit_var)) x in
  let lc = interp_hyp_list ist env sigma lc in
  let lc = in_list (val_tag wit_var) lc in
  Ftactic.return lc
  end

(* Interprets tactic expressions : returns a "constr" *)
and interp_ltac_constr ist e : EConstr.t Ftactic.t =
  let (>>=) = Ftactic.bind in
  begin Proofview.tclORELSE
      (val_interp ist e)
      begin function (err, info) -> match err with
        | Not_found ->
            Ftactic.enter begin fun gl ->
              let env = Proofview.Goal.env gl in
              Proofview.tclLIFT begin
                debugging_step ist (fun () ->
                  str "evaluation failed for" ++ fnl() ++
                    Pptactic.pr_glob_tactic env e)
              end
            <*> Proofview.tclZERO Not_found
            end
        | err -> Proofview.tclZERO ~info err
      end
  end >>= fun result ->
  Ftactic.enter begin fun gl ->
  let env = Proofview.Goal.env gl in
  let sigma = project gl in
  try
    let cresult = coerce_to_closed_constr env result in
    Proofview.tclLIFT begin
      debugging_step ist (fun () ->
        Pptactic.pr_glob_tactic env e ++ fnl() ++
          str " has value " ++ fnl() ++
          pr_econstr_env env sigma cresult)
    end <*>
    Ftactic.return cresult
  with CannotCoerceTo _ ->
    let env = Proofview.Goal.env gl in
    Tacticals.New.tclZEROMSG (str "Must evaluate to a closed term" ++ fnl() ++
      str "offending expression: " ++ fnl() ++ pr_inspect env e result)
  end


(* Interprets tactic expressions : returns a "tactic" *)
and interp_tactic ist tac : unit Proofview.tactic =
  Ftactic.run (val_interp ist tac) (fun v -> tactic_of_value ist v)

(* Provides a "name" for the trace to atomic tactics *)
and name_atomic ?env tacexpr tac : unit Proofview.tactic =
  begin match env with
  | Some e -> Proofview.tclUNIT e
  | None -> Proofview.tclENV
  end >>= fun env ->
  Proofview.tclEVARMAP >>= fun sigma ->
  let name () = Pptactic.pr_atomic_tactic env sigma tacexpr in
  Proofview.Trace.name_tactic name tac

(* Interprets a primitive tactic *)
and interp_atomic ist tac : unit Proofview.tactic =
  match tac with
  (* Basic tactics *)
  | TacIntroPattern (ev,l) ->
      Proofview.Goal.enter begin fun gl ->
        let env = Proofview.Goal.env gl in
        let sigma = project gl in
        let sigma,l' = interp_intro_pattern_list_as_list ist env sigma l in
        Tacticals.New.tclWITHHOLES ev
        (name_atomic ~env
          (TacIntroPattern (ev,l))
          (* spiwack: print uninterpreted, not sure if it is the
             expected behaviour. *)
          (Tactics.intro_patterns ev l')) sigma
      end
  | TacApply (a,ev,cb,cl) ->
      (* spiwack: until the tactic is in the monad *)
      Proofview.Trace.name_tactic (fun () -> Pp.str"<apply>") begin
      Proofview.Goal.enter begin fun gl ->
        let env = Proofview.Goal.env gl in
        let sigma = project gl in
	let l = List.map (fun (k,c) ->
          let loc, f = interp_open_constr_with_bindings_loc ist c in
            (k,(make ?loc f))) cb
	in
        let sigma,tac = match cl with
          | None -> sigma, Tactics.apply_with_delayed_bindings_gen a ev l
          | Some cl ->
              let sigma,(id,cl) = interp_in_hyp_as ist env sigma cl in
              sigma, Tactics.apply_delayed_in a ev id l cl in
        Tacticals.New.tclWITHHOLES ev tac sigma
      end
      end
  | TacElim (ev,(keep,cb),cbo) ->
      Proofview.Goal.enter begin fun gl ->
        let env = Proofview.Goal.env gl in
        let sigma = project gl in 
        let sigma, cb = interp_open_constr_with_bindings ist env sigma cb in
        let sigma, cbo = Option.fold_left_map (interp_open_constr_with_bindings ist env) sigma cbo in
        let named_tac =
          let tac = Tactics.elim ev keep cb cbo in
          name_atomic ~env (TacElim (ev,(keep,cb),cbo)) tac
        in
        Tacticals.New.tclWITHHOLES ev named_tac sigma
      end
  | TacCase (ev,(keep,cb)) ->
      Proofview.Goal.enter begin fun gl ->
        let sigma = project gl in
        let env = Proofview.Goal.env gl in
        let sigma, cb = interp_open_constr_with_bindings ist env sigma cb in
        let named_tac =
          let tac = Tactics.general_case_analysis ev keep cb in
          name_atomic ~env (TacCase(ev,(keep,cb))) tac
        in
        Tacticals.New.tclWITHHOLES ev named_tac sigma
      end
  | TacMutualFix (id,n,l) ->
      (* spiwack: until the tactic is in the monad *)
      Proofview.Trace.name_tactic (fun () -> Pp.str"<mutual fix>") begin
      Proofview.Goal.nf_enter begin fun gl ->
        let env = pf_env gl in
        let f sigma (id,n,c) =
          let (sigma,c_interp) = interp_type ist env sigma c in
	  sigma , (interp_ident ist env sigma id,n,c_interp) in
        let (sigma,l_interp) =
          Evd.MonadR.List.map_right (fun c sigma -> f sigma c) l (project gl)
        in
        Tacticals.New.tclTHEN (Proofview.Unsafe.tclEVARS sigma)
        (Tactics.mutual_fix (interp_ident ist env sigma id) n l_interp 0)
      end
      end
  | TacMutualCofix (id,l) ->
      (* spiwack: until the tactic is in the monad *)
      Proofview.Trace.name_tactic (fun () -> Pp.str"<mutual cofix>") begin
      Proofview.Goal.nf_enter begin fun gl ->
        let env = pf_env gl in
        let f sigma (id,c) =
	  let (sigma,c_interp) = interp_type ist env sigma c in
	  sigma , (interp_ident ist env sigma id,c_interp) in
        let (sigma,l_interp) =
          Evd.MonadR.List.map_right (fun c sigma -> f sigma c) l (project gl)
        in
        Tacticals.New.tclTHEN (Proofview.Unsafe.tclEVARS sigma)
        (Tactics.mutual_cofix (interp_ident ist env sigma id) l_interp 0)
      end
      end
  | TacAssert (ev,b,t,ipat,c) ->
      Proofview.Goal.enter begin fun gl ->
        let env = Proofview.Goal.env gl in
        let sigma = project gl in
        let (sigma,c) =
          let expected_type =
            if Option.is_empty t then WithoutTypeConstraint else IsType in
          let flags = open_constr_use_classes_flags () in
          interp_open_constr ~expected_type ~flags ist env sigma c
        in
        let sigma, ipat' = interp_intro_pattern_option ist env sigma ipat in
        let tac = Option.map (Option.map (interp_tactic ist)) t in
        Tacticals.New.tclWITHHOLES ev
        (name_atomic ~env
          (TacAssert(ev,b,Option.map (Option.map ignore) t,ipat,c))
          (Tactics.forward b tac ipat' c)) sigma
      end
  | TacGeneralize cl ->
      Proofview.Goal.enter begin fun gl ->
        let sigma = project gl in
        let env = Proofview.Goal.env gl in
        let sigma, cl = interp_constr_with_occurrences_and_name_as_list ist env sigma cl in
        Tacticals.New.tclWITHHOLES false
        (name_atomic ~env
          (TacGeneralize cl)
          (Tactics.generalize_gen cl)) sigma
      end
  | TacLetTac (ev,na,c,clp,b,eqpat) ->
      Proofview.Goal.enter begin fun gl ->
        let env = Proofview.Goal.env gl in
        let sigma = project gl in
        let clp = interp_clause ist env sigma clp in
        let eqpat = interp_intro_pattern_naming_option ist env sigma eqpat in
        if Locusops.is_nowhere clp (* typically "pose" *) then
        (* We try to fully-typecheck the term *)
          let flags = open_constr_use_classes_flags () in
          let (sigma,c_interp) = interp_open_constr ~flags ist env sigma c in
          let let_tac b na c cl eqpat =
            let id = Option.default (make IntroAnonymous) eqpat in
            let with_eq = if b then None else Some (true,id) in
            Tactics.letin_tac with_eq na c None cl
          in
          let na = interp_name ist env sigma na in
          Tacticals.New.tclWITHHOLES ev
          (name_atomic ~env
            (TacLetTac(ev,na,c_interp,clp,b,eqpat))
            (let_tac b na c_interp clp eqpat)) sigma
        else
        (* We try to keep the pattern structure as much as possible *)
          let let_pat_tac b na c cl eqpat =
            let id = Option.default (make IntroAnonymous) eqpat in
            let with_eq = if b then None else Some (true,id) in
            Tactics.letin_pat_tac ev with_eq na c cl
          in
          let (sigma',c) = interp_pure_open_constr ist env sigma c in
          name_atomic ~env
            (TacLetTac(ev,na,c,clp,b,eqpat))
	    (Tacticals.New.tclWITHHOLES ev
               (let_pat_tac b (interp_name ist env sigma na)
                  (sigma,c) clp eqpat) sigma')
      end

  (* Derived basic tactics *)
  | TacInductionDestruct (isrec,ev,(l,el)) ->
      (* spiwack: some unknown part of destruct needs the goal to be
         prenormalised. *)
      Proofview.Goal.nf_enter begin fun gl ->
        let env = Proofview.Goal.env gl in
        let sigma = project gl in
        let sigma,l =
          List.fold_left_map begin fun sigma (c,(ipato,ipats),cls) ->
            (* TODO: move sigma as a side-effect *)
             (* spiwack: the [*p] variants are for printing *)
            let cp = c in
            let c = interp_destruction_arg ist gl c in
            let ipato = interp_intro_pattern_naming_option ist env sigma ipato in
            let ipatsp = ipats in
            let sigma,ipats = interp_or_and_intro_pattern_option ist env sigma ipats in
            let cls = Option.map (interp_clause ist env sigma) cls in
            sigma,((c,(ipato,ipats),cls),(cp,(ipato,ipatsp),cls))
          end sigma l
        in
        let l,lp = List.split l in
        let sigma,el =
          Option.fold_left_map (interp_open_constr_with_bindings ist env) sigma el in
        Tacticals.New.tclTHEN (Proofview.Unsafe.tclEVARS sigma)
        (name_atomic ~env
          (TacInductionDestruct(isrec,ev,(lp,el)))
            (Tactics.induction_destruct isrec ev (l,el)))
      end

  (* Conversion *)
  | TacReduce (r,cl) ->
      Proofview.Goal.nf_enter begin fun gl ->
        let (sigma,r_interp) = interp_red_expr ist (pf_env gl) (project gl) r in
        Tacticals.New.tclTHEN (Proofview.Unsafe.tclEVARS sigma)
        (Tactics.reduce r_interp (interp_clause ist (pf_env gl) (project gl) cl))
      end
  | TacChange (None,c,cl) ->
      (* spiwack: until the tactic is in the monad *)
      Proofview.Trace.name_tactic (fun () -> Pp.str"<change>") begin
      Proofview.Goal.enter begin fun gl ->
        let is_onhyps = match cl.onhyps with
          | None | Some [] -> true
          | _ -> false
        in
        let is_onconcl = match cl.concl_occs with
          | AllOccurrences | NoOccurrences -> true
          | _ -> false
        in
        let c_interp patvars sigma =
	  let lfun' = Id.Map.fold (fun id c lfun ->
	    Id.Map.add id (Value.of_constr c) lfun) 
	    patvars ist.lfun
	  in
	  let ist = { ist with lfun = lfun' } in
            if is_onhyps && is_onconcl
            then interp_type ist (pf_env gl) sigma c
            else interp_constr ist (pf_env gl) sigma c
        in
        Tactics.change None c_interp (interp_clause ist (pf_env gl) (project gl) cl)
      end
      end
  | TacChange (Some op,c,cl) ->
      (* spiwack: until the tactic is in the monad *)
      Proofview.Trace.name_tactic (fun () -> Pp.str"<change>") begin
      Proofview.Goal.enter begin fun gl ->
        let env = Proofview.Goal.env gl in
        let sigma = project gl in
        let op = interp_typed_pattern ist env sigma op in
        let to_catch = function Not_found -> true | e -> CErrors.is_anomaly e in
        let c_interp patvars sigma =
          let lfun' = Id.Map.fold (fun id c lfun ->
            Id.Map.add id (Value.of_constr c) lfun) 
            patvars ist.lfun
          in
          let ist = { ist with lfun = lfun' } in
            try
              interp_constr ist env sigma c
            with e when to_catch e (* Hack *) ->
              user_err  (strbrk "Failed to get enough information from the left-hand side to type the right-hand side.")
        in
        Tactics.change (Some op) c_interp (interp_clause ist env sigma cl)
      end
      end


  (* Equality and inversion *)
  | TacRewrite (ev,l,cl,by) ->
      Proofview.Goal.enter begin fun gl ->
        let l' = List.map (fun (b,m,(keep,c)) ->
          let f env sigma =
            interp_open_constr_with_bindings ist env sigma c
          in
	  (b,m,keep,f)) l in
        let env = Proofview.Goal.env gl in
        let sigma = project gl in
        let cl = interp_clause ist env sigma cl in
        name_atomic ~env
          (TacRewrite (ev,l,cl,Option.map ignore by))
          (Equality.general_multi_rewrite ev l' cl
             (Option.map (fun by -> Tacticals.New.tclCOMPLETE (interp_tactic ist by),
               Equality.Naive)
                by))
      end
  | TacInversion (DepInversion (k,c,ids),hyp) ->
      Proofview.Goal.enter begin fun gl ->
        let env = Proofview.Goal.env gl in
        let sigma = project gl in
        let (sigma,c_interp) =
          match c with
          | None -> sigma , None
          | Some c ->
              let (sigma,c_interp) = interp_constr ist env sigma c in
              sigma , Some c_interp
        in
        let dqhyps = interp_declared_or_quantified_hypothesis ist env sigma hyp in
        let sigma,ids_interp = interp_or_and_intro_pattern_option ist env sigma ids in
        Tacticals.New.tclWITHHOLES false
        (name_atomic ~env
          (TacInversion(DepInversion(k,c_interp,ids),dqhyps))
          (Inv.dinv k c_interp ids_interp dqhyps)) sigma
      end
  | TacInversion (NonDepInversion (k,idl,ids),hyp) ->
      Proofview.Goal.enter begin fun gl ->
        let env = Proofview.Goal.env gl in
        let sigma = project gl in
        let hyps = interp_hyp_list ist env sigma idl in
        let dqhyps = interp_declared_or_quantified_hypothesis ist env sigma hyp in
        let sigma, ids_interp = interp_or_and_intro_pattern_option ist env sigma ids in
        Tacticals.New.tclWITHHOLES false
        (name_atomic ~env
          (TacInversion (NonDepInversion (k,hyps,ids),dqhyps))
          (Inv.inv_clause k ids_interp hyps dqhyps)) sigma
      end
  | TacInversion (InversionUsing (c,idl),hyp) ->
      Proofview.Goal.enter begin fun gl ->
        let env = Proofview.Goal.env gl in
        let sigma = project gl in
        let (sigma,c_interp) = interp_constr ist env sigma c in
        let dqhyps = interp_declared_or_quantified_hypothesis ist env sigma hyp in
        let hyps = interp_hyp_list ist env sigma idl in
        Tacticals.New.tclTHEN (Proofview.Unsafe.tclEVARS sigma)
        (name_atomic ~env
          (TacInversion (InversionUsing (c_interp,hyps),dqhyps))
          (Leminv.lemInv_clause dqhyps c_interp hyps))
      end

(* Initial call for interpretation *)

let default_ist () =
  let extra = TacStore.set TacStore.empty f_debug (get_debug ()) in
  { lfun = Id.Map.empty; extra = extra }

let eval_tactic t =
  Proofview.tclUNIT () >>= fun () -> (* delay for [default_ist] *)
  Proofview.tclLIFT db_initialize <*>
  interp_tactic (default_ist ()) t

let eval_tactic_ist ist t =
  Proofview.tclLIFT db_initialize <*>
  interp_tactic ist t

(* globalization + interpretation *)


let interp_tac_gen lfun avoid_ids debug t =
  Proofview.Goal.enter begin fun gl ->
  let env = Proofview.Goal.env gl in
  let extra = TacStore.set TacStore.empty f_debug debug in
  let extra = TacStore.set extra f_avoid_ids avoid_ids in
  let ist = { lfun = lfun; extra = extra } in
  let ltacvars = Id.Map.domain lfun in
  interp_tactic ist
    (intern_pure_tactic { (Genintern.empty_glob_sign env) with ltacvars } t)
  end

let interp t = interp_tac_gen Id.Map.empty Id.Set.empty (get_debug()) t

(* Used to hide interpretation for pretty-print, now just launch tactics *)
(* [global] means that [t] should be internalized outside of goals. *)
let hide_interp global t ot =
  let hide_interp env =
    let ist = Genintern.empty_glob_sign env in
    let te = intern_pure_tactic ist t in
    let t = eval_tactic te in
    match ot with
    | None -> t
    | Some t' -> Tacticals.New.tclTHEN t t'
  in
  if global then
    Proofview.tclENV >>= fun env ->
    hide_interp env
  else
    Proofview.Goal.enter begin fun gl ->
      hide_interp (Proofview.Goal.env gl)
    end

(***************************************************************************)
(** Register standard arguments *)

let register_interp0 wit f =
  let open Ftactic.Notations in
  let interp ist v =
    f ist v >>= fun v -> Ftactic.return (Val.inject (val_tag wit) v)
  in
  Geninterp.register_interp0 wit interp

let def_intern ist x = (ist, x)
let def_subst _ x = x
let def_interp ist x = Ftactic.return x

let declare_uniform t =
  Genintern.register_intern0 t def_intern;
  Genintern.register_subst0 t def_subst;
  register_interp0 t def_interp

let () =
  declare_uniform wit_unit

let () =
  declare_uniform wit_int

let () =
  declare_uniform wit_bool

let () =
  declare_uniform wit_string

let lift f = (); fun ist x -> Ftactic.enter begin fun gl ->
  let env = Proofview.Goal.env gl in
  let sigma = Proofview.Goal.sigma gl in
  Ftactic.return (f ist env sigma x)
end

let lifts f = (); fun ist x -> Ftactic.enter begin fun gl ->
  let env = Proofview.Goal.env gl in
  let sigma = Proofview.Goal.sigma gl in
  let (sigma, v) = f ist env sigma x in
  Proofview.tclTHEN (Proofview.Unsafe.tclEVARS sigma)
  (Ftactic.return v)
end

let interp_bindings' ist bl = Ftactic.return begin fun env sigma ->
  interp_bindings ist env sigma bl
  end

let interp_constr_with_bindings' ist c = Ftactic.return begin fun env sigma ->
  interp_constr_with_bindings ist env sigma c
  end

let interp_open_constr_with_bindings' ist c = Ftactic.return begin fun env sigma ->
  interp_open_constr_with_bindings ist env sigma c
  end

let interp_destruction_arg' ist c = Ftactic.enter begin fun gl ->
  Ftactic.return (interp_destruction_arg ist gl c)
end

let interp_pre_ident ist env sigma s =
  s |> Id.of_string |> interp_ident ist env sigma |> Id.to_string

let () =
  register_interp0 wit_int_or_var (fun ist n -> Ftactic.return (interp_int_or_var ist n));
  register_interp0 wit_ref (lift interp_reference);
  register_interp0 wit_pre_ident (lift interp_pre_ident);
  register_interp0 wit_ident (lift interp_ident);
  register_interp0 wit_var (lift interp_hyp);
  register_interp0 wit_intro_pattern (lifts interp_intro_pattern);
  register_interp0 wit_clause_dft_concl (lift interp_clause);
  register_interp0 wit_constr (lifts interp_constr);
  register_interp0 wit_tacvalue (fun ist v -> Ftactic.return v);
  register_interp0 wit_red_expr (lifts interp_red_expr);
  register_interp0 wit_quant_hyp (lift interp_declared_or_quantified_hypothesis);
  register_interp0 wit_open_constr (lifts interp_open_constr);
  register_interp0 wit_bindings interp_bindings';
  register_interp0 wit_constr_with_bindings interp_constr_with_bindings';
  register_interp0 wit_open_constr_with_bindings interp_open_constr_with_bindings';
  register_interp0 wit_destruction_arg interp_destruction_arg';
  ()

let () =
  let interp ist tac = Ftactic.return (Value.of_closure ist tac) in
  register_interp0 wit_tactic interp

let () =
  let interp ist tac = interp_tactic ist tac >>= fun () -> Ftactic.return () in
  register_interp0 wit_ltac interp

let () =
  register_interp0 wit_uconstr (fun ist c -> Ftactic.enter begin fun gl ->
    Ftactic.return (interp_uconstr ist (Proofview.Goal.env gl) (Tacmach.New.project gl) c)
  end)

(***************************************************************************)
(* Other entry points *)

let val_interp ist tac k = Ftactic.run (val_interp ist tac) k

let interp_ltac_constr ist c k = Ftactic.run (interp_ltac_constr ist c) k

let interp_redexp env sigma r =
  let ist = default_ist () in
  let gist = { fully_empty_glob_sign with genv = env; } in
  interp_red_expr ist env sigma (intern_red_expr gist r)

(***************************************************************************)
(* Backwarding recursive needs of tactic glob/interp/eval functions *)

let _ =
  let eval lfun env sigma ty tac =
    let extra = TacStore.set TacStore.empty f_debug (get_debug ()) in
    let ist = { lfun = lfun; extra; } in
    let tac = interp_tactic ist tac in
    let (c, sigma) = Pfedit.refine_by_tactic env sigma ty tac in
    (EConstr.of_constr c, sigma)
  in
  Pretyping.register_constr_interp0 wit_tactic eval

let vernac_debug b =
  set_debug (if b then Tactic_debug.DebugOn 0 else Tactic_debug.DebugOff)

let _ =
  let open Goptions in
  declare_bool_option
    { optdepr  = false;
      optname  = "Ltac debug";
      optkey   = ["Ltac";"Debug"];
      optread  = (fun () -> get_debug () != Tactic_debug.DebugOff);
      optwrite = vernac_debug }

let _ =
  let open Goptions in
  declare_bool_option
    { optdepr  = false;
      optname  = "Ltac debug";
      optkey   = ["Debug";"Ltac"];
      optread  = (fun () -> get_debug () != Tactic_debug.DebugOff);
      optwrite = vernac_debug }

let () = Hook.set Vernacentries.interp_redexp_hook interp_redexp