summaryrefslogtreecommitdiff
path: root/src/reduce.sml
blob: 8691b93afae1616091fad150126bc3539db78d5f (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
(* Copyright (c) 2008-2011, 2013, Adam Chlipala
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
 *   and/or other materials provided with the distribution.
 * - The names of contributors may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *)

(* Simplify a Core program algebraically *)

structure Reduce :> REDUCE = struct

open Core

structure IS = IntBinarySet
structure IM = IntBinaryMap

structure E = CoreEnv

fun multiLiftConInCon n c =
    if n = 0 then
        c
    else
        multiLiftConInCon (n - 1) (E.liftConInCon 0 c)

fun multiLiftExpInExp n e =
    if n = 0 then
        e
    else
        multiLiftExpInExp (n - 1) (E.liftExpInExp 0 e)

val count = CoreUtil.Exp.foldB {kind = fn (_, _, c) => c,
                                con = fn (_, _, c) => c,
                                exp = fn (x, e, c) =>
                                         case e of
                                             ERel x' => if x = x' then c + 1 else c
                                           | _ => c,
                                bind = fn (x, b) =>
                                          case b of
                                              CoreUtil.Exp.RelE _ => x+1
                                            | _ => x} 0 0

val dangling =
    CoreUtil.Exp.existsB {kind = fn _ => false,
                          con = fn _ => false,
                          exp = fn (n, e) =>
                                   case e of
                                       ERel n' => n' >= n
                                     | _ => false,
                          bind = fn (n, b) =>
                                    case b of
                                        CoreUtil.Exp.RelE _ => n + 1
                                      | _ => n}

val cdangling =
    CoreUtil.Exp.existsB {kind = fn _ => false,
                          con = fn (n, c) =>
                                   case c of
                                       CRel n' => n' >= n
                                     | _ => false,
                          exp = fn _ => false,
                          bind = fn (n, b) =>
                                    case b of
                                        CoreUtil.Exp.RelC _ => n + 1
                                      | _ => n}

datatype env_item =
         UnknownK
       | KnownK of kind

       | UnknownC
       | KnownC of con

       | UnknownE
       | KnownE of exp

       | Lift of int * int * int

val edepth = foldl (fn (UnknownE, n) => n + 1
                     | (KnownE _, n) => n + 1
                     | (_, n) => n) 0

val edepth' = foldl (fn (UnknownE, n) => n + 1
                      | (KnownE _, n) => n + 1
                      | (Lift (_, _, n'), n) => n + n'
                      | (_, n) => n) 0

val cdepth = foldl (fn (UnknownC, n) => n + 1
                     | (KnownC _, n) => n + 1
                     | (_, n) => n) 0

val cdepth' = foldl (fn (UnknownC, n) => n + 1
                      | (KnownC _, n) => n + 1
                      | (Lift (_, n', _), n) => n + n'
                      | (_, n) => n) 0

type env = env_item list

fun ei2s ei =
    case ei of
        UnknownK => "UK"
      | KnownK _ => "KK"
      | UnknownC => "UC"
      | KnownC _ => "KC"
      | UnknownE => "UE"
      | KnownE _ => "KE"
      | Lift (_, n1, n2) => "(" ^ Int.toString n1 ^ ", " ^ Int.toString n2 ^ ")"

fun e2s env = String.concatWith " " (map ei2s env)

(*val deKnown = List.filter (fn KnownC _ => false
                            | KnownE _ => false
                            | KnownK _ => false
                            | _ => true)*)

val deKnown = ListUtil.mapConcat (fn KnownC _ => []
                                   | KnownE _ => []
                                   | KnownK _ => []
                                   | Lift (nk, nc, ne) => List.tabulate (nk, fn _ => UnknownK)
                                                          @ List.tabulate (nc, fn _ => UnknownC)
                                                          @ List.tabulate (ne, fn _ => UnknownE)
                                   | x => [x])

datatype result = Yes of env | No | Maybe

fun match (env, p : pat, e : exp) =
    let
        val baseline = length env

        fun match (env, p, e) =
            case (#1 p, #1 e) of
                (PWild, _) => Yes env
              | (PVar (x, t), _) => Yes (KnownE (multiLiftExpInExp (length env - baseline) e) :: env)

              | (PPrim p, EPrim p') =>
                if Prim.equal (p, p') then
                    Yes env
                else
                    No

              | (PCon (_, PConVar n1, _, NONE), ECon (_, PConVar n2, _, NONE)) =>
                if n1 = n2 then
                    Yes env
                else
                    No

              | (PCon (_, PConVar n1, _, SOME p), ECon (_, PConVar n2, _, SOME e)) =>
                if n1 = n2 then
                    match (env, p, e)
                else
                    No

              | (PCon (_, PConFfi {mod = m1, con = con1, ...}, _, NONE),
                 ECon (_, PConFfi {mod = m2, con = con2, ...}, _, NONE)) =>
                if m1 = m2 andalso con1 = con2 then
                    Yes env
                else
                    No

              | (PCon (_, PConFfi {mod = m1, con = con1, ...}, _, SOME ep),
                 ECon (_, PConFfi {mod = m2, con = con2, ...}, _, SOME e)) =>
                if m1 = m2 andalso con1 = con2 then
                    match (env, p, e)
                else
                    No

              | (PRecord xps, ERecord xes) =>
                if List.exists (fn ((CName _, _), _, _) => false
                                 | _ => true) xes then
                    Maybe
                else
                    let
                        fun consider (xps, env) =
                            case xps of
                                [] => Yes env
                              | (x, p, _) :: rest =>
                                case List.find (fn ((CName x', _), _, _) => x' = x
                                                 | _ => false) xes of
                                    NONE => No
                                  | SOME (_, e, _) =>
                                    case match (env, p, e) of
                                        No => No
                                      | Maybe => Maybe
                                      | Yes env => consider (rest, env)
                    in
                        consider (xps, env)
                    end

              | _ => Maybe
    in
        match (env, p, e)
    end

fun returnType m loc =
    (TCFun ("a", (KType, loc),
            (TFun ((CRel 0, loc),
                   (CApp (multiLiftConInCon 1 m, (CRel 0, loc)), loc)), loc)), loc)

fun bindType m loc =
    (TCFun ("a", (KType, loc),
            (TCFun ("b", (KType, loc),
                    (TFun ((CApp (multiLiftConInCon 2 m, (CRel 1, loc)), loc),
                           (TFun ((TFun ((CRel 1, loc),
                                         (CApp (multiLiftConInCon 2 m, (CRel 0, loc)), loc)),
                                   loc),
                                  (CApp (multiLiftConInCon 2 m, (CRel 0, loc)), loc)), loc)),
                     loc)), loc)), loc)

fun monadRecord m loc =
    (TRecord (CRecord ((KType, loc),
                       [((CName "Return", loc),
                         returnType m loc),
                        ((CName "Bind", loc),
                         bindType m loc)]), loc), loc)

fun passive (e : exp) =
    case #1 e of
        EPrim _ => true
      | ERel _ => true
      | ENamed _ => true
      | ECon (_, _, _, NONE) => true
      | ECon (_, _, _, SOME e) => passive e
      | EFfi _ => true
      | EAbs _ => true
      | ECAbs _ => true
      | EKAbs _ => true
      | ERecord xes => List.all (passive o #2) xes
      | EField (e, _, _) => passive e
      | _ => false

fun notFfi (t : con) =
    case #1 t of
        CFfi _ => false
      | _ => true

fun kindConAndExp (namedC, namedE) =
    let
        fun kind env (all as (k, loc)) =
            case k of
                KType => all
              | KArrow (k1, k2) => (KArrow (kind env k1, kind env k2), loc)
              | KName => all
              | KRecord k => (KRecord (kind env k), loc)
              | KUnit => all
              | KTuple ks => (KTuple (map (kind env) ks), loc)

              | KRel n =>
                let
                    fun find (n', env, nudge, lift) =
                        case env of
                            [] => raise Fail "Reduce.kind: KRel"
                          | UnknownC :: rest => find (n', rest, nudge, lift)
                          | KnownC _ :: rest => find (n', rest, nudge, lift)
                          | UnknownE :: rest => find (n', rest, nudge, lift)
                          | KnownE _ :: rest => find (n', rest, nudge, lift)
                          | Lift (lift', _, _) :: rest => find (n', rest, nudge + lift', lift + lift')
                          | UnknownK :: rest =>
                            if n' = 0 then
                                (KRel (n + nudge), loc)
                            else
                                find (n' - 1, rest, nudge, lift + 1)
                          | KnownK k :: rest =>
                            if n' = 0 then
                                kind (Lift (lift, 0, 0) :: rest) k
                            else
                                find (n' - 1, rest, nudge - 1, lift)
                in
                    find (n, env, 0, 0)
                end
              | KFun (x, k) => (KFun (x, kind (UnknownK :: env) k), loc)

        fun con env (all as (c, loc)) =
            ((*Print.prefaces "con" [("c", CorePrint.p_con CoreEnv.empty all)];*)
            case c of
                TFun (c1, c2) => (TFun (con env c1, con env c2), loc)
              | TCFun (x, k, c2) => (TCFun (x, kind env k, con (UnknownC :: env) c2), loc)
              | TKFun (x, c2) => (TKFun (x, con (UnknownK :: env) c2), loc)
              | TRecord c => (TRecord (con env c), loc)

              | CRel n =>
                let
                    fun find (n', env, nudge, liftK, liftC) =
                        case env of
                            [] => raise Fail "Reduce.con: CRel"
                          | UnknownK :: rest => find (n', rest, nudge, liftK + 1, liftC)
                          | KnownK _ :: rest => find (n', rest, nudge, liftK, liftC)
                          | UnknownE :: rest => find (n', rest, nudge, liftK, liftC)
                          | KnownE _ :: rest => find (n', rest, nudge, liftK, liftC)
                          | Lift (liftK', liftC', _) :: rest => find (n', rest, nudge + liftC',
                                                                      liftK + liftK', liftC + liftC')
                          | UnknownC :: rest =>
                            if n' = 0 then
                                (CRel (n + nudge), loc)
                            else
                                find (n' - 1, rest, nudge, liftK, liftC + 1)
                          | KnownC c :: rest =>
                            if n' = 0 then
                                con (Lift (liftK, liftC, 0) :: rest) c
                            else
                                find (n' - 1, rest, nudge - 1, liftK, liftC)
                in
                    (*print (Int.toString n ^ ": " ^ e2s env ^ "\n");*)
                    find (n, env, 0, 0, 0)
                end

              | CNamed n =>
                (case IM.find (namedC, n) of
                     NONE => all
                   | SOME c => c)

              | CFfi ("Basis", "monad") => (CAbs ("m", (KArrow ((KType, loc), (KType, loc)), loc), monadRecord (CRel 0, loc) loc), loc)

              | CFfi _ => all
              | CApp (c1, c2) =>
                let
                    val c1 = con env c1
                    val c2 = con env c2
                in
                    case #1 c1 of
                        CAbs (_, _, b) =>
                        con (KnownC c2 :: deKnown env) b

                      | CApp ((CMap (dom, ran), _), f) =>
                        (case #1 c2 of
                             CRecord (_, []) => (CRecord (kind env ran, []), loc)
                           | CRecord (_, (x, c) :: rest) =>
                             con (deKnown env)
                                 (CConcat ((CRecord (ran, [(x, (CApp (f, c), loc))]), loc),
                                           (CApp (c1, (CRecord (kind env dom, rest), loc)), loc)), loc)
                           | _ => (CApp (c1, c2), loc))                           

                      | _ => (CApp (c1, c2), loc)
                end
              | CAbs (x, k, b) => (CAbs (x, kind env k, con (UnknownC :: env) b), loc)

              | CKApp (c1, k) =>
                let
                    val c1 = con env c1
                in
                    case #1 c1 of
                        CKAbs (_, b) =>
                        con (KnownK k :: deKnown env) b

                      | _ => (CKApp (c1, kind env k), loc)
                end
              | CKAbs (x, b) => (CKAbs (x, con (UnknownK :: env) b), loc)

              | CName _ => all

              | CRecord (k, xcs) => (CRecord (kind env k, map (fn (x, c) => (con env x, con env c)) xcs), loc)
              | CConcat (c1, c2) =>
                let
                    val c1 = con env c1
                    val c2 = con env c2
                in
                    case (#1 c1, #1 c2) of
                        (CRecord (k, xcs1), CRecord (_, xcs2)) =>
                        (CRecord (kind env k, xcs1 @ xcs2), loc)
                      | (CRecord (_, []), _) => c2
                      | (_, CRecord (_, [])) => c1
                      | _ => (CConcat (c1, c2), loc)
                end
              | CMap (dom, ran) => (CMap (kind env dom, kind env ran), loc)

              | CUnit => all

              | CTuple cs => (CTuple (map (con env) cs), loc)
              | CProj (c, n) =>
                let
                    val c = con env c
                in
                    case #1 c of
                        CTuple cs => List.nth (cs, n - 1)
                      | _ => (CProj (c, n), loc)
                end)

        fun patCon pc =
            case pc of
                PConVar _ => pc
              | PConFfi {mod = m, datatyp, params, con = c, arg, kind} =>
                PConFfi {mod = m, datatyp = datatyp, params = params, con = c,
                         arg = Option.map (con (map (fn _ => UnknownC) params)) arg,
                         kind = kind}


        val k = (KType, ErrorMsg.dummySpan)
        fun doPart e (this as (x, t), rest) =
            ((x, (EField (e, x, {field = t, rest = (CRecord (k, rest), #2 t)}), #2 t), t),
             this :: rest)

        fun exp env (all as (e, loc)) =
            let
                (*val () = Print.prefaces "exp" [("e", CorePrint.p_exp CoreEnv.empty all),
                                               ("env", Print.PD.string (e2s env))]*)
                (*val () = if dangling (edepth env) all then
                             (Print.prefaces "exp" [("e", CorePrint.p_exp CoreEnv.empty all),
                                                    ("env", Print.PD.string (e2s env))];
                              raise Fail "!")
                         else
                             ()*)
                (*val () = if cdangling (cdepth env) all then
                             Print.prefaces "Bad exp" [("e", CorePrint.p_exp CoreEnv.empty all),
                                                       ("env", Print.PD.string (e2s env))]
                         else
                             ()*)

                fun patBinds (p, _) =
                    case p of
                        PWild => 0
                      | PVar _ => 1
                      | PPrim _ => 0
                      | PCon (_, _, _, NONE) => 0
                      | PCon (_, _, _, SOME p) => patBinds p
                      | PRecord xpts => foldl (fn ((_, p, _), n) => n + patBinds p) 0 xpts

                val r = case e of
                            EPrim _ => all
                          | ERel n =>
                            let
                                fun find (n', env, nudge, liftK, liftC, liftE) =
                                    case env of
                                        [] => raise Fail ("Reduce.exp: ERel (" ^ ErrorMsg.spanToString loc ^ ")")
                                      | UnknownK :: rest => find (n', rest, nudge, liftK + 1, liftC, liftE)
                                      | KnownK _ :: rest => find (n', rest, nudge, liftK, liftC, liftE)
                                      | UnknownC :: rest => find (n', rest, nudge, liftK, liftC + 1, liftE)
                                      | KnownC _ :: rest => find (n', rest, nudge, liftK, liftC, liftE)
                                      | Lift (liftK', liftC', liftE') :: rest =>
                                        find (n', rest, nudge + liftE',
                                              liftK + liftK', liftC + liftC', liftE + liftE')
                                      | UnknownE :: rest =>
                                        if n' = 0 then
                                            (ERel (n + nudge), loc)
                                        else
                                            find (n' - 1, rest, nudge, liftK, liftC, liftE + 1)
                                      | KnownE e :: rest =>
                                        if n' = 0 then
                                            ((*print "SUBSTITUTING\n";*)
                                             exp (Lift (liftK, liftC, liftE) :: rest) e)
                                        else
                                            find (n' - 1, rest, nudge - 1, liftK, liftC, liftE)
                            in
                                (*print (Int.toString n ^ ": " ^ e2s env ^ "\n");*)
                                find (n, env, 0, 0, 0, 0)
                            end
                          | ENamed n =>
                            (case IM.find (namedE, n) of
                                 NONE => all
                               | SOME e => e)
                          | ECon (dk, pc, cs, eo) => (ECon (dk, patCon pc,
                                                            map (con env) cs, Option.map (exp env) eo), loc)

                          | EFfi ("Basis", "return") =>
                            (ECAbs ("m", (KArrow ((KType, loc), (KType, loc)), loc),
                                    (ECAbs ("a", (KType, loc),
                                            (EAbs ("m", monadRecord (CRel 1, loc) loc, returnType (CRel 1, loc) loc,
                                                   (ECApp ((EField ((ERel 0, loc), (CName "Return", loc),
                                                                    {field = returnType (CRel 1, loc) loc,
                                                                     rest = (CRecord ((KType, loc),
                                                                                      [((CName "Bind", loc), bindType (CRel 1, loc) loc)]),
                                                                             loc)}), loc), (CRel 0, loc)), loc)), loc)), loc)), loc)

                          | EFfi ("Basis", "bind") =>
                            (ECAbs ("m", (KArrow ((KType, loc), (KType, loc)), loc),
                                    (ECAbs ("a", (KType, loc),
                                            (ECAbs ("b", (KType, loc),
                                                    (EAbs ("m", monadRecord (CRel 2, loc) loc, bindType (CRel 2, loc) loc,
                                                           (ECApp ((ECApp ((EField ((ERel 0, loc), (CName "Bind", loc),
                                                                                    {field = bindType (CRel 2, loc) loc,
                                                                                     rest = (CRecord ((KType, loc),
                                                                                                      [((CName "Return", loc),
                                                                                                        returnType (CRel 2, loc) loc)]),
                                                                                             loc)}), loc), (CRel 1, loc)), loc),
                                                                  (CRel 0, loc)), loc)), loc)), loc)), loc)), loc)

                          | EFfi ("Basis", "mkMonad") =>
                            (ECAbs ("m", (KArrow ((KType, loc), (KType, loc)), loc),
                                    (EAbs ("m", monadRecord (CRel 0, loc) loc, monadRecord (CRel 0, loc) loc,
                                           (ERel 0, loc)), loc)), loc)

                          | EFfi ("Basis", "transaction_monad") =>
                            (ERecord [((CName "Return", loc),
                                       (EFfi ("Basis", "transaction_return"), loc),
                                       returnType (CFfi ("Basis", "transaction"), loc) loc),
                                      ((CName "Bind", loc),
                                       (EFfi ("Basis", "transaction_bind"), loc),
                                       bindType (CFfi ("Basis", "transaction"), loc) loc)], loc)

                          | EFfi ("Basis", "signal_monad") =>
                            (ERecord [((CName "Return", loc),
                                       (EFfi ("Basis", "signal_return"), loc),
                                       returnType (CFfi ("Basis", "signal"), loc) loc),
                                      ((CName "Bind", loc),
                                       (EFfi ("Basis", "signal_bind"), loc),
                                       bindType (CFfi ("Basis", "signal"), loc) loc)], loc)

                          | EFfi _ => all
                          | EFfiApp (m, f, es) => (EFfiApp (m, f, map (fn (e, t) => (exp env e, con env t)) es), loc)

                          (*| EApp (
                           (EApp
                                ((EApp ((ECApp ((ECApp ((ECApp ((EFfi ("Basis", "bind"), loc), _), _), t1), _), t2), _),
                                        (EFfi ("Basis", "transaction_monad"), _)), _),
                                 (ECase (ed, pes, {disc, ...}), _)), _),
                           trans2) =>
                           let
                               val e' = (EFfi ("Basis", "bind"), loc)
                               val e' = (ECApp (e', (CFfi ("Basis", "transaction"), loc)), loc)
                               val e' = (ECApp (e', t1), loc)
                               val e' = (ECApp (e', t2), loc)
                               val e' = (EApp (e', (EFfi ("Basis", "transaction_monad"), loc)), loc)

                               val pes = map (fn (p, e) =>
                                                 let
                                                     val e' = (EApp (e', e), loc)
                                                     val e' = (EApp (e',
                                                                     multiLiftExpInExp (E.patBindsN p)
                                                                                       trans2), loc)
                                                     val e' = exp env e'
                                                 in
                                                     (p, e')
                                                 end) pes
                           in
                               (ECase (exp env ed,
                                       pes,
                                       {disc = con env disc,
                                        result = (CApp ((CFfi ("Basis", "transaction"), loc), con env t2), loc)}),
                                loc)
                           end*)

                          | EApp (e1, e2) =>
                            let
                                val env' = deKnown env

                                val e1 = exp env e1
                                val e2 = exp env e2
                            in
                                case #1 e1 of
                                    ELet (x, t, e1', e2') =>
                                    (ELet (x, t, e1', exp (UnknownE :: env') (EApp (e2', E.liftExpInExp 0 e2), loc)), loc)

                                  | EAbs (x, dom, _, b) =>
                                    if count b <= 1 orelse passive e2 orelse ESpecialize.functionInside IS.empty dom then
                                        let
                                            val r = exp (KnownE e2 :: env') b
                                        in
                                            (*Print.prefaces "eapp" [("b", CorePrint.p_exp CoreEnv.empty b),
                                                                     ("env", Print.PD.string (e2s env')),
                                                                     ("e2", CorePrint.p_exp CoreEnv.empty e2),
                                                                     ("r", CorePrint.p_exp CoreEnv.empty r)];*)
                                            r
                                        end
                                    else
                                        let
                                            val dom = con env' dom
                                            val r = exp (UnknownE :: env') b
                                        in
                                            (*Print.prefaces "El skippo" [("x", Print.PD.string x),
                                                                        ("e2", CorePrint.p_exp CoreEnv.empty e2)];*)
                                            (ELet (x, dom, e2, r), loc)
                                        end

                                  | ECase (e, pes, cc as {disc, result = res as (TFun (_, c2), _)}) =>
                                    let
                                        val pes' = map (fn (p, body) =>
                                                           let
                                                               val env' = List.tabulate (patBinds p, fn _ => UnknownE) @ deKnown env
                                                               val body' = exp env' (EApp (body, multiLiftExpInExp (patBinds p) e2), #2 body)
                                                           in
                                                               (p, body')
                                                           end) pes

                                        val cc' = {disc = disc, result = c2}
                                    in
                                        (ECase (e, pes', cc'), loc)
                                    end
                                  | _ => (EApp (e1, e2), loc)
                            end

                          | EAbs (x, dom, ran, e) => (EAbs (x, con env dom, con env ran, exp (UnknownE :: env) e), loc)

                          | ECApp (e, c) =>
                            let
                                val e = exp env e
                                val c = con env c
                            in
                                case #1 e of
                                    ECAbs (_, _, b) =>
                                    let
                                        val r = exp (KnownC c :: deKnown env) b
                                    in
                                        (*Print.prefaces "csub" [("l", Print.PD.string (ErrorMsg.spanToString loc)),
                                                               ("env", Print.PD.string (e2s (deKnown env))),
                                                               ("b", CorePrint.p_exp CoreEnv.empty b),
                                                               ("c", CorePrint.p_con CoreEnv.empty c),
                                                               ("r", CorePrint.p_exp CoreEnv.empty r)];*)
                                        r
                                    end
                                  | ECase (e, pes, cc as {disc, result = res as (TCFun (_, _, c'), _)}) =>
                                    let
                                        val pes' = map (fn (p, body) =>
                                                        let
                                                            val env' = List.tabulate (patBinds p, fn _ => UnknownE) @ deKnown env

                                                            val body' = exp env' (ECApp (body, c), #2 body)
                                                        in
                                                            (p, body')
                                                        end) pes

                                        val c' = E.subConInCon (0, c) c'
                                        val cc' = {disc = disc, result = c'}
                                    in
                                        (ECase (e, pes', cc'), loc)
                                    end
                                  | _ => (ECApp (e, c), loc)
                            end

                          | ECAbs (x, k, e) => (ECAbs (x, kind env k, exp (UnknownC :: env) e), loc)

                          | EKApp (e, k) =>
                            let
                                val e = exp env e
                            in
                                case #1 e of
                                    EKAbs (_, b) =>
                                    let
                                        val r = exp (KnownK k :: deKnown env) b
                                    in
                                        (*Print.prefaces "ksub" [("l", Print.PD.string (ErrorMsg.spanToString loc)),
                                                               ("b", CorePrint.p_exp CoreEnv.empty b),
                                                               ("k", CorePrint.p_kind CoreEnv.empty k),
                                                               ("r", CorePrint.p_exp CoreEnv.empty r)];*)
                                        r
                                    end
                                  | _ => (EKApp (e, kind env k), loc)
                            end

                          | EKAbs (x, e) => (EKAbs (x, exp (UnknownK :: env) e), loc)

                          | ERecord xcs => (ERecord (map (fn (x, e, t) => (con env x, exp env e, con env t)) xcs), loc)
                          | EField (e, c, {field, rest}) =>
                            let
                                val e = exp env e
                                val c = con env c

                                fun default () = (EField (e, c, {field = con env field, rest = con env rest}), loc)
                            in
                                case (#1 e, #1 c) of
                                    (ERecord xcs, CName x) =>
                                    (case List.find (fn ((CName x', _), _, _) => x' = x | _ => false) xcs of
                                         NONE => default ()
                                       | SOME (_, e, _) => e)
                                  | _ => default ()
                            end

                          | EConcat (e1, c1, e2, c2) =>
                            let
                                val e1 = exp env e1
                                val e2 = exp env e2
                            in
                                case (#1 e1, #1 e2) of
                                    (ERecord xes1, ERecord xes2) => (ERecord (xes1 @ xes2), loc)
                                  | _ =>
                                    let
                                        val c1 = con env c1
                                        val c2 = con env c2
                                    in
                                        case (#1 c1, #1 c2) of
                                            (CRecord (k, xcs1), CRecord (_, xcs2)) =>
                                            let
                                                val (xes1, rest) = ListUtil.foldlMap (doPart e1) [] xcs1
                                                val (xes2, _) = ListUtil.foldlMap (doPart e2) rest xcs2
                                            in
                                                exp (deKnown env) (ERecord (xes1 @ xes2), loc)
                                            end
                                          | _ => (EConcat (e1, c1, e2, c2), loc)
                                    end
                            end

                          | ECut (e, c, {field, rest}) =>
                            let
                                val e = exp env e
                                val c = con env c

                                fun default () =
                                    let
                                        val rest = con env rest
                                    in
                                        case #1 rest of
                                            CRecord (k, xcs) =>
                                            let
                                                val (xes, _) = ListUtil.foldlMap (doPart e) [] xcs
                                            in
                                                exp (deKnown env) (ERecord xes, loc)
                                            end
                                          | _ => (ECut (e, c, {field = con env field, rest = rest}), loc)
                                    end
                            in
                                case (#1 e, #1 c) of
                                    (ERecord xes, CName x) =>
                                    if List.all (fn ((CName _, _), _, _) => true | _ => false) xes then
                                        (ERecord (List.filter (fn ((CName x', _), _, _) => x' <> x
                                                                | _ => raise Fail "Reduce: ECut") xes), loc)
                                    else
                                        default ()
                                  | _ => default ()
                            end

                          | ECutMulti (e, c, {rest}) =>
                            let
                                val e = exp env e
                                val c = con env c

                                fun default () =
                                    let
                                        val rest = con env rest
                                    in
                                        case #1 rest of
                                            CRecord (k, xcs) =>
                                            let
                                                val (xes, _) = ListUtil.foldlMap (doPart e) [] xcs
                                            in
                                                exp (deKnown env) (ERecord xes, loc)
                                            end
                                          | _ => (ECutMulti (e, c, {rest = rest}), loc)
                                    end
                            in
                                case (#1 e, #1 c) of
                                    (ERecord xes, CRecord (_, xcs)) =>
                                    if List.all (fn ((CName _, _), _, _) => true | _ => false) xes
                                       andalso List.all (fn ((CName _, _), _) => true | _ => false) xcs then
                                        (ERecord (List.filter (fn ((CName x', _), _, _) =>
                                                                  List.all (fn ((CName x, _), _) => x' <> x
                                                                             | _ => raise Fail "Reduce: ECutMulti [1]") xcs
                                                                | _ => raise Fail "Reduce: ECutMulti [2]") xes), loc)
                                    else
                                        default ()
                                  | _ => default ()
                            end

                          | ECase (_, [((PRecord [], _), e)], _) => exp env e
                          | ECase (_, [((PWild, _), e)], _) => exp env e

                          | ECase (e, pes, {disc, result}) =>
                            let
                                fun pat (all as (p, loc)) =
                                    case p of
                                        PWild => all
                                      | PVar (x, t) => (PVar (x, con env t), loc)
                                      | PPrim _ => all
                                      | PCon (dk, pc, cs, po) =>
                                        (PCon (dk, patCon pc, map (con env) cs, Option.map pat po), loc)
                                      | PRecord xpts => (PRecord (map (fn (x, p, t) => (x, pat p, con env t)) xpts), loc)

                                fun push () =
                                    (ECase (exp env e,
                                            map (fn (p, e) => (pat p,
                                                               exp (List.tabulate (patBinds p,
                                                                                fn _ => UnknownE) @ env) e))
                                                pes, {disc = con env disc, result = con env result}), loc)

                                fun search pes =
                                    case pes of
                                        [] => push ()
                                      | (p, body) :: pes =>
                                        case match (env, p, e) of
                                            No => search pes
                                          | Maybe => push ()
                                          | Yes env' => exp env' body
                            in
                                search pes
                            end

                          | EWrite e => (EWrite (exp env e), loc)
                          | EClosure (n, es) => (EClosure (n, map (exp env) es), loc)

                          | ELet (x, t, e1, e2) =>
                            let
                                val e1' = exp env e1

                                val t = con env t
                            in
                                if notFfi t andalso (passive e1' orelse count e2 <= 1 orelse ESpecialize.functionInside IS.empty t) then
                                    exp (KnownE e1 :: env) e2
                                else
                                    (ELet (x, t, e1', exp (UnknownE :: env) e2), loc)
                            end

                          | EServerCall (n, es, t, fm) => (EServerCall (n, map (exp env) es, con env t, fm), loc)
            in
                (*if dangling (edepth' (deKnown env)) r then
                    (Print.prefaces "exp" [("e", CorePrint.p_exp CoreEnv.empty all),
                                           ("r", CorePrint.p_exp CoreEnv.empty r)];
                     raise Fail "!!")
                else
                    ();*)
                (*if cdangling (cdepth' (deKnown env)) r then
                    (Print.prefaces "exp" [("e", CorePrint.p_exp CoreEnv.empty all),
                                           ("r", CorePrint.p_exp CoreEnv.empty r)];
                     raise Fail "!!")
                else
                    ();*)
                r
            end
    in
        {kind = kind, con = con, exp = exp}
    end

fun kind namedC env k = #kind (kindConAndExp (namedC, IM.empty)) env k
fun con namedC env c = #con (kindConAndExp (namedC, IM.empty)) env c
fun exp (namedC, namedE) env e = #exp (kindConAndExp (namedC, namedE)) env e

fun reduce file =
    let
        val uses = CoreUtil.File.fold {kind = fn (_, m) => m,
                                       con = fn (_, m) => m,
                                       exp = fn (e, m) =>
                                                case e of
                                                    ENamed n => IM.insert (m, n, 1 + Option.getOpt (IM.find (m, n), 0))
                                                  | _ => m,
                                       decl = fn (_, m) => m}
                                      IM.empty file

        fun isPoly names = CoreUtil.Con.exists {kind = fn _ => false,
                                                con = fn TCFun _ => true
                                                       | TKFun _ => true
                                                       | CNamed n => IS.member (names, n)
                                                       | _ => false}

        val size = CoreUtil.Exp.fold {kind = fn (_, n) => n,
                                      con = fn (_, n) => n,
                                      exp = fn (_, n) => n + 1} 0

        fun mayInline (polyC, n, t, e, s) =
            let
                fun isPolicy t =
                    case #1 t of
                        CFfi ("Basis", "sql_policy") => true
                      | TFun (_, t) => isPolicy t
                      | _ => false
            in
                not (Settings.checkNeverInline s) andalso
                case IM.find (uses, n) of
                    NONE => false
                  | SOME count => count <= 1
                                  orelse (case #1 e of
                                              ERecord _ => true
                                            | _ => false)
                                  orelse isPolicy t
                                  orelse isPoly polyC t
                                  orelse size e <= Settings.getCoreInline ()
            end

        fun doDecl (d as (_, loc), st as (polyC, namedC, namedE)) =
            case #1 d of
                DCon (x, n, k, c) =>
                let
                    val k = kind namedC [] k
                    val c = con namedC [] c
                in
                    ((DCon (x, n, k, c), loc),
                     (if isPoly polyC c then
                          IS.add (polyC, n)
                      else
                          polyC,
                      IM.insert (namedC, n, c),
                      namedE))
                end
              | DDatatype dts =>
                ((DDatatype (map (fn (x, n, ps, cs) =>
                                     let
                                         val env = map (fn _ => UnknownC) ps
                                     in
                                         (x, n, ps, map (fn (x, n, co) => (x, n, Option.map (con namedC env) co)) cs)
                                     end) dts), loc),
                 (if List.exists (fn (_, _, _, cs) => List.exists (fn (_, _, co) => case co of
                                                                                        NONE => false
                                                                                      | SOME c => isPoly polyC c) cs)
                                 dts then
                      foldl (fn ((_, n, _, _), polyC) => IS.add (polyC, n)) polyC dts
                  else
                      polyC,
                  namedC,
                  namedE))
              | DVal (x, n, t, e, s) =>
                let
                    val t = con namedC [] t
                    val e = exp (namedC, namedE) [] e
                in
                    ((DVal (x, n, t, e, s), loc),
                     (polyC,
                      namedC,
                      if mayInline (polyC, n, t, e, s) then
                          IM.insert (namedE, n, e)
                      else
                          namedE))
                end
              | DValRec vis =>
                ((DValRec (map (fn (x, n, t, e, s) => (x, n, con namedC [] t,
                                                       exp (namedC, namedE) [] e, s)) vis), loc),
                 st)
              | DExport _ => (d, st)
              | DTable (s, n, c, s', pe, pc, ce, cc) => ((DTable (s, n, con namedC [] c, s',
                                                                  exp (namedC, namedE) [] pe,
                                                                  con namedC [] pc,
                                                                  exp (namedC, namedE) [] ce,
                                                                  con namedC [] cc), loc), st)
              | DSequence _ => (d, st)
              | DView (s, n, s', e, c) => ((DView (s, n, s', exp (namedC, namedE) [] e, con namedC [] c), loc), st)
              | DDatabase _ => (d, st)
              | DCookie (s, n, c, s') => ((DCookie (s, n, con namedC [] c, s'), loc), st)
              | DStyle (s, n, s') => ((DStyle (s, n, s'), loc), st)
              | DTask (e1, e2) =>
                let
                    val e1 = exp (namedC, namedE) [] e1
                    val e2 = exp (namedC, namedE) [] e2
                in
                    ((DTask (e1, e2), loc),
                     (polyC,
                      namedC,
                      namedE))
                end
              | DPolicy e1 =>
                let
                    val e1 = exp (namedC, namedE) [] e1
                in
                    ((DPolicy e1, loc),
                     (polyC,
                      namedC,
                      namedE))
                end
              | DOnError _ => (d, st)

        val (file, _) = ListUtil.foldlMap doDecl (IS.empty, IM.empty, IM.empty) file
    in
        file
    end

end