aboutsummaryrefslogtreecommitdiffhomepage
path: root/proofs/refiner.ml
blob: be32aadd91f8ad83f3362cd6fe264c0cce0af984 (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
(************************************************************************)
(*         *   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 Pp
open CErrors
open Util
open Evd
open Proof_type
open Logic

module NamedDecl = Context.Named.Declaration

let sig_it x = x.it
let project x = x.sigma

(* Getting env *)

let pf_env gls = Global.env_of_context (Goal.V82.hyps (project gls) (sig_it gls))
let pf_hyps gls = EConstr.named_context_of_val (Goal.V82.hyps (project gls) (sig_it gls))

let refiner pr goal_sigma =
  let (sgl,sigma') = prim_refiner pr goal_sigma.sigma goal_sigma.it in
  { it = sgl; sigma = sigma'; }

(* Profiling refiner *)
let refiner = 
  if Flags.profile then
    let refiner_key = CProfile.declare_profile "refiner" in
      CProfile.profile2 refiner_key refiner
  else refiner

(*********************)
(*   Tacticals       *)
(*********************)


let unpackage glsig = (ref (glsig.sigma)), glsig.it

let repackage r v = {it = v; sigma = !r; }

let apply_sig_tac r tac g =
  Control.check_for_interrupt (); (* Breakpoint *)
  let glsigma = tac (repackage r g) in
  r := glsigma.sigma;
  glsigma.it

(* [goal_goal_list : goal sigma -> goal list sigma] *)
let goal_goal_list gls = {it=[gls.it]; sigma=gls.sigma; }

(* identity tactic without any message *)
let tclIDTAC gls = goal_goal_list gls

(* the message printing identity tactic *)
let tclIDTAC_MESSAGE s gls =
  Feedback.msg_info (hov 0 s); tclIDTAC gls

(* General failure tactic *)
let tclFAIL_s s gls = user_err ~hdr:"Refiner.tclFAIL_s" (str s)

(* A special exception for levels for the Fail tactic *)
exception FailError of int * Pp.t Lazy.t

(* The Fail tactic *)
let tclFAIL lvl s g = raise (FailError (lvl,lazy s))

let tclFAIL_lazy lvl s g = raise (FailError (lvl,s))

let start_tac gls =
  let sigr, g = unpackage gls in
  (sigr, [g])

let finish_tac (sigr,gl) = repackage sigr gl

(* Apply [tacfi.(i)] on the first n subgoals, [tacli.(i)] on the last
   m subgoals, and [tac] on the others *)
let thens3parts_tac tacfi tac tacli (sigr,gs) =
  let nf = Array.length tacfi in
  let nl = Array.length tacli in
  let ng = List.length gs in
  if ng<nf+nl then user_err ~hdr:"Refiner.thensn_tac" (str "Not enough subgoals.");
  let gll =
      (List.map_i (fun i ->
        apply_sig_tac sigr (if i<nf then tacfi.(i) else if i>=ng-nl then tacli.(nl-ng+i) else tac))
	0 gs) in
    (sigr,List.flatten gll)

(* Apply [taci.(i)] on the first n subgoals and [tac] on the others *)
let thensf_tac taci tac = thens3parts_tac taci tac [||]

(* Apply [tac i] on the ith subgoal (no subgoals number check) *)
let thensi_tac tac (sigr,gs) =
  let gll =
    List.map_i (fun i -> apply_sig_tac sigr (tac i)) 1 gs in
  (sigr, List.flatten gll)

let then_tac tac = thensf_tac [||] tac

(* [tclTHENS3PARTS tac1 [|t1 ; ... ; tn|] tac2 [|t'1 ; ... ; t'm|] gls]
   applies the tactic [tac1] to [gls] then, applies [t1], ..., [tn] to
   the first [n] resulting subgoals, [t'1], ..., [t'm] to the last [m]
   subgoals and [tac2] to the rest of the subgoals in the middle. Raises an
   error if the number of resulting subgoals is strictly less than [n+m] *)
let tclTHENS3PARTS tac1 tacfi tac tacli gls =
  finish_tac (thens3parts_tac tacfi tac tacli (then_tac tac1 (start_tac gls)))

(* [tclTHENSFIRSTn tac1 [|t1 ; ... ; tn|] tac2 gls] applies the tactic [tac1]
   to [gls] and applies [t1], ..., [tn] to the first [n] resulting
   subgoals, and [tac2] to the others subgoals. Raises an error if
   the number of resulting subgoals is strictly less than [n] *)
let tclTHENSFIRSTn tac1 taci tac = tclTHENS3PARTS tac1 taci tac [||]

(* [tclTHENSLASTn tac1 tac2 [|t1 ;...; tn|] gls] applies the tactic [tac1]
   to [gls] and applies [t1], ..., [tn] to the last [n] resulting
   subgoals, and [tac2] to the other subgoals. Raises an error if the
   number of resulting subgoals is strictly less than [n] *)
let tclTHENSLASTn tac1 tac taci = tclTHENS3PARTS tac1 [||] tac taci

(* [tclTHEN_i tac taci gls] applies the tactic [tac] to [gls] and applies
   [(taci i)] to the i_th resulting subgoal (starting from 1), whatever the
   number of subgoals is *)
let tclTHEN_i tac taci gls =
  finish_tac (thensi_tac taci (then_tac tac (start_tac gls)))

let tclTHENLASTn tac1 taci = tclTHENSLASTn tac1 tclIDTAC taci
let tclTHENFIRSTn tac1 taci = tclTHENSFIRSTn tac1 taci tclIDTAC

(* [tclTHEN tac1 tac2 gls] applies the tactic [tac1] to [gls] and applies
   [tac2] to every resulting subgoals *)
let tclTHEN tac1 tac2 = tclTHENS3PARTS tac1 [||] tac2 [||]

(* [tclTHENSV tac1 [t1 ; ... ; tn] gls] applies the tactic [tac1] to
   [gls] and applies [t1],..., [tn] to the [n] resulting subgoals. Raises
   an error if the number of resulting subgoals is not [n] *)
let tclTHENSV tac1 tac2v =
  tclTHENS3PARTS tac1 tac2v (tclFAIL_s "Wrong number of tactics.") [||]

let tclTHENS tac1 tac2l = tclTHENSV tac1 (Array.of_list tac2l)

(* [tclTHENLAST tac1 tac2 gls] applies the tactic [tac1] to [gls] and [tac2]
   to the last resulting subgoal *)
let tclTHENLAST tac1 tac2 = tclTHENSLASTn tac1 tclIDTAC [|tac2|]

(* [tclTHENFIRST tac1 tac2 gls] applies the tactic [tac1] to [gls] and [tac2]
   to the first resulting subgoal *)
let tclTHENFIRST tac1 tac2 = tclTHENSFIRSTn tac1 [|tac2|] tclIDTAC

(* [tclTHENLIST [t1;..;tn]] applies [t1] then [t2] ... then [tn]. More
   convenient than [tclTHEN] when [n] is large. *)
let rec tclTHENLIST = function
    [] -> tclIDTAC
  | t1::tacl -> tclTHEN t1 (tclTHENLIST tacl)

(* [tclMAP f [x1..xn]] builds [(f x1);(f x2);...(f xn)] *)
let tclMAP tacfun l =
  List.fold_right (fun x -> (tclTHEN (tacfun x))) l tclIDTAC

(* PROGRESS tac ptree applies tac to the goal ptree and fails if tac leaves
the goal unchanged *)
let tclPROGRESS tac ptree =
  let rslt = tac ptree in
  if Goal.V82.progress rslt ptree then rslt
  else user_err ~hdr:"Refiner.PROGRESS" (str"Failed to progress.")

(* Execute tac, show the names of new hypothesis names created by tac
   in the "as" format and then forget everything. From the logical
   point of view [tclSHOWHYPS tac] is therefore equivalent to idtac,
   except that it takes the time and memory of tac and prints "as"
   information). The resulting (unchanged) goals are printed *after*
   the as-expression, which forces pg to some gymnastic.
   TODO: Have something similar (better?) in the xml protocol.
   NOTE: some tactics delete hypothesis and reuse names (induction,
   destruct), this is not detected by this tactical. *)
let tclSHOWHYPS (tac : tactic) (goal: Goal.goal Evd.sigma)
    :Proof_type.goal list Evd.sigma =
  let oldhyps = pf_hyps goal in
  let rslt:Proof_type.goal list Evd.sigma = tac goal in
  let { it = gls; sigma = sigma; } = rslt in
  let hyps =
    List.map (fun gl -> pf_hyps { it = gl; sigma=sigma; }) gls in
  let cmp d1 d2 = Names.Id.equal (NamedDecl.get_id d1) (NamedDecl.get_id d2) in
  let newhyps =
    List.map
      (fun hypl -> List.subtract cmp hypl oldhyps)
      hyps
  in
  let s = 
    let frst = ref true in
    List.fold_left
    (fun acc lh -> acc ^ (if !frst then (frst:=false;"") else " | ")
      ^ (List.fold_left
	   (fun acc d -> (Names.Id.to_string (NamedDecl.get_id d)) ^ " " ^ acc)
	   "" lh))
    "" newhyps in
  Feedback.msg_notice
    (str "<infoH>"
      ++  (hov 0 (str s))
      ++  (str "</infoH>"));
  tclIDTAC goal;;


let catch_failerror (e, info) =
  if catchable_exception e then Control.check_for_interrupt ()
  else match e with
  | FailError (0,_) ->
      Control.check_for_interrupt ()
  | FailError (lvl,s) ->
    iraise (FailError (lvl - 1, s), info)
  | e -> iraise (e, info)
  (** FIXME: do we need to add a [Errors.push] here? *)

(* ORELSE0 t1 t2 tries to apply t1 and if it fails, applies t2 *)
let tclORELSE0 t1 t2 g =
  try
    t1 g
  with (* Breakpoint *)
    | e when CErrors.noncritical e ->
      let e = CErrors.push e in catch_failerror e; t2 g

(* ORELSE t1 t2 tries to apply t1 and if it fails or does not progress,
   then applies t2 *)
let tclORELSE t1 t2 = tclORELSE0 (tclPROGRESS t1) t2

(* applies t1;t2then if t1 succeeds or t2else if t1 fails
   t2* are called in terminal position (unless t1 produces more than
   1 subgoal!) *)
let tclORELSE_THEN t1 t2then t2else gls =
  match
    try Some(tclPROGRESS t1 gls)
    with e when CErrors.noncritical e ->
      let e = CErrors.push e in catch_failerror e; None
  with
    | None -> t2else gls
    | Some sgl ->
        let sigr, gl = unpackage sgl in
        finish_tac (then_tac t2then  (sigr,gl))

(* TRY f tries to apply f, and if it fails, leave the goal unchanged *)
let tclTRY f = (tclORELSE0 f tclIDTAC)

let tclTHENTRY f g = (tclTHEN f (tclTRY g))

(* Try the first tactic that does not fail in a list of tactics *)

let rec tclFIRST = function
  | [] -> tclFAIL_s "No applicable tactic."
  |  t::rest -> tclORELSE0 t (tclFIRST rest)

let ite_gen tcal tac_if continue tac_else gl=
  let success=ref false in
  let tac_if0 gl=
    let result=tac_if gl in
      success:=true;result in
  let tac_else0 e gl=
    if !success then
      iraise e
    else
      try
        tac_else gl
      with
        e' when CErrors.noncritical e' -> iraise e in
  try
    tcal tac_if0 continue gl
  with (* Breakpoint *)
  | e when CErrors.noncritical e ->
    let e = CErrors.push e in catch_failerror e; tac_else0 e gl

(* Try the first tactic and, if it succeeds, continue with
   the second one, and if it fails, use the third one *)

let tclIFTHENELSE=ite_gen tclTHEN

(* Idem with tclTHENS and tclTHENSV *)

let tclIFTHENSELSE=ite_gen tclTHENS

let tclIFTHENSVELSE=ite_gen tclTHENSV

let tclIFTHENTRYELSEMUST tac1 tac2 gl =
  tclIFTHENELSE tac1 (tclTRY tac2) tac2 gl

(* Fails if a tactic did not solve the goal *)
let tclCOMPLETE tac = tclTHEN tac (tclFAIL_s "Proof is not complete.")

(* Try the first thats solves the current goal *)
let tclSOLVE tacl = tclFIRST (List.map tclCOMPLETE tacl)


(* Iteration tacticals *)

let tclDO n t =
  let rec dorec k =
    if k < 0 then user_err ~hdr:"Refiner.tclDO"
      (str"Wrong argument : Do needs a positive integer.");
    if Int.equal k 0 then tclIDTAC
    else if Int.equal k 1 then t else (tclTHEN t (dorec (k-1)))
  in
  dorec n


(* Beware: call by need of CAML, g is needed *)
let rec tclREPEAT t g =
  tclORELSE_THEN t (tclREPEAT t) tclIDTAC g

let tclAT_LEAST_ONCE t = (tclTHEN t (tclREPEAT t))

(* Repeat on the first subgoal (no failure if no more subgoal) *)
let rec tclREPEAT_MAIN t g =
  (tclORELSE (tclTHEN_i t (fun i -> if Int.equal i 1 then (tclREPEAT_MAIN t) else
    tclIDTAC)) tclIDTAC) g

(* Change evars *)
let tclEVARS sigma gls = tclIDTAC {gls with sigma=sigma}

let tclEVARUNIVCONTEXT ctx gls = tclIDTAC {gls with sigma= Evd.set_universe_context gls.sigma ctx}

(* Push universe context *)
let tclPUSHCONTEXT rigid ctx tac gl = 
  tclTHEN (tclEVARS (Evd.merge_context_set rigid (project gl) ctx)) tac gl

let tclPUSHEVARUNIVCONTEXT ctx gl = 
  tclEVARS (Evd.merge_universe_context (project gl) ctx) gl

let tclPUSHCONSTRAINTS cst gl = 
  tclEVARS (Evd.add_constraints (project gl) cst) gl