src/Pure/Isar/calculation.ML
author wenzelm
Thu Apr 21 22:02:06 2005 +0200 (2005-04-21)
changeset 15801 d2f5ca3c048d
parent 15570 8d8c70b41bab
child 15973 5fd94d84470f
permissions -rw-r--r--
superceded by Pure.thy and CPure.thy;
wenzelm@6778
     1
(*  Title:      Pure/Isar/calculation.ML
wenzelm@6778
     2
    ID:         $Id$
wenzelm@6778
     3
    Author:     Markus Wenzel, TU Muenchen
wenzelm@6778
     4
wenzelm@6778
     5
Support for calculational proofs.
wenzelm@6778
     6
*)
wenzelm@6778
     7
wenzelm@6778
     8
signature CALCULATION =
wenzelm@6778
     9
sig
wenzelm@6778
    10
  val print_global_rules: theory -> unit
wenzelm@6778
    11
  val print_local_rules: Proof.context -> unit
wenzelm@6778
    12
  val trans_add_global: theory attribute
wenzelm@6778
    13
  val trans_del_global: theory attribute
wenzelm@6778
    14
  val trans_add_local: Proof.context attribute
wenzelm@6778
    15
  val trans_del_local: Proof.context attribute
wenzelm@12379
    16
  val sym_add_global: theory attribute
wenzelm@12379
    17
  val sym_del_global: theory attribute
wenzelm@12379
    18
  val sym_add_local: Proof.context attribute
wenzelm@12379
    19
  val sym_del_local: Proof.context attribute
wenzelm@12379
    20
  val symmetric_global: theory attribute
wenzelm@12379
    21
  val symmetric_local: Proof.context attribute
wenzelm@12055
    22
  val also: thm list option -> (Proof.context -> thm list -> unit)
wenzelm@12055
    23
    -> Proof.state -> Proof.state Seq.seq
wenzelm@12055
    24
  val finally: thm list option -> (Proof.context -> thm list -> unit)
wenzelm@12055
    25
    -> Proof.state -> Proof.state Seq.seq
wenzelm@12055
    26
  val moreover: (Proof.context -> thm list -> unit) -> Proof.state -> Proof.state
wenzelm@12055
    27
  val ultimately: (Proof.context -> thm list -> unit) -> Proof.state -> Proof.state
wenzelm@6778
    28
end;
wenzelm@6778
    29
wenzelm@6778
    30
structure Calculation: CALCULATION =
wenzelm@6778
    31
struct
wenzelm@6778
    32
wenzelm@6778
    33
(** global and local calculation data **)
wenzelm@6778
    34
wenzelm@8300
    35
(* theory data kind 'Isar/calculation' *)
wenzelm@6778
    36
wenzelm@12379
    37
fun print_rules prt x (trans, sym) =
wenzelm@12379
    38
  [Pretty.big_list "transitivity rules:" (map (prt x) (NetRules.rules trans)),
wenzelm@12379
    39
    Pretty.big_list "symmetry rules:" (map (prt x) sym)]
wenzelm@12379
    40
  |> Pretty.chunks |> Pretty.writeln;
wenzelm@6778
    41
wenzelm@6778
    42
structure GlobalCalculationArgs =
wenzelm@6778
    43
struct
wenzelm@6778
    44
  val name = "Isar/calculation";
wenzelm@12379
    45
  type T = thm NetRules.T * thm list
wenzelm@6778
    46
wenzelm@12379
    47
  val empty = (NetRules.elim, []);
wenzelm@6778
    48
  val copy = I;
wenzelm@6778
    49
  val prep_ext = I;
wenzelm@12379
    50
  fun merge ((trans1, sym1), (trans2, sym2)) =
wenzelm@12379
    51
    (NetRules.merge (trans1, trans2), Drule.merge_rules (sym1, sym2));
wenzelm@12055
    52
  val print = print_rules Display.pretty_thm_sg;
wenzelm@6778
    53
end;
wenzelm@6778
    54
wenzelm@6778
    55
structure GlobalCalculation = TheoryDataFun(GlobalCalculationArgs);
wenzelm@15801
    56
val _ = Context.add_setup [GlobalCalculation.init];
wenzelm@6778
    57
val print_global_rules = GlobalCalculation.print;
wenzelm@6778
    58
wenzelm@6778
    59
wenzelm@6778
    60
(* proof data kind 'Isar/calculation' *)
wenzelm@6778
    61
wenzelm@6778
    62
structure LocalCalculationArgs =
wenzelm@6778
    63
struct
wenzelm@6778
    64
  val name = "Isar/calculation";
wenzelm@12379
    65
  type T = (thm NetRules.T * thm list) * (thm list * int) option;
wenzelm@6778
    66
skalberg@15531
    67
  fun init thy = (GlobalCalculation.get thy, NONE);
wenzelm@12055
    68
  fun print ctxt (rs, _) = print_rules ProofContext.pretty_thm ctxt rs;
wenzelm@6778
    69
end;
wenzelm@6778
    70
wenzelm@6778
    71
structure LocalCalculation = ProofDataFun(LocalCalculationArgs);
wenzelm@15801
    72
val _ = Context.add_setup [LocalCalculation.init];
wenzelm@13371
    73
val get_local_rules = #1 o LocalCalculation.get o Proof.context_of;
wenzelm@6778
    74
val print_local_rules = LocalCalculation.print;
wenzelm@6778
    75
wenzelm@6778
    76
wenzelm@6778
    77
(* access calculation *)
wenzelm@6778
    78
wenzelm@6778
    79
fun get_calculation state =
wenzelm@13371
    80
  (case #2 (LocalCalculation.get (Proof.context_of state)) of
skalberg@15531
    81
    NONE => NONE
skalberg@15531
    82
  | SOME (thms, lev) => if lev = Proof.level state then SOME thms else NONE);
wenzelm@6778
    83
wenzelm@7414
    84
fun put_calculation thms state =
wenzelm@13371
    85
  Proof.map_context
skalberg@15531
    86
    (LocalCalculation.put (get_local_rules state, SOME (thms, Proof.level state))) state;
wenzelm@6778
    87
wenzelm@6787
    88
fun reset_calculation state =
skalberg@15531
    89
  Proof.map_context (LocalCalculation.put (get_local_rules state, NONE)) state;
wenzelm@6787
    90
wenzelm@6778
    91
wenzelm@6778
    92
wenzelm@6778
    93
(** attributes **)
wenzelm@6778
    94
wenzelm@12379
    95
(* add/del rules *)
wenzelm@12379
    96
wenzelm@12379
    97
fun global_att f (x, thm) = (GlobalCalculation.map (f thm) x, thm);
wenzelm@12379
    98
fun local_att f (x, thm) = (LocalCalculation.map (apfst (f thm)) x, thm);
wenzelm@6778
    99
wenzelm@12379
   100
val trans_add_global = global_att (apfst o NetRules.insert);
wenzelm@12379
   101
val trans_del_global = global_att (apfst o NetRules.delete);
wenzelm@12379
   102
val trans_add_local = local_att (apfst o NetRules.insert);
wenzelm@12379
   103
val trans_del_local = local_att (apfst o NetRules.delete);
wenzelm@6778
   104
skalberg@15531
   105
val sym_add_global = global_att (apsnd o Drule.add_rule) o ContextRules.elim_query_global NONE;
wenzelm@12402
   106
val sym_del_global = global_att (apsnd o Drule.del_rule) o ContextRules.rule_del_global;
skalberg@15531
   107
val sym_add_local = local_att (apsnd o Drule.add_rule) o ContextRules.elim_query_local NONE;
wenzelm@12402
   108
val sym_del_local = local_att (apsnd o Drule.del_rule) o ContextRules.rule_del_local;
wenzelm@12379
   109
wenzelm@12379
   110
wenzelm@12379
   111
(* symmetry *)
wenzelm@12379
   112
wenzelm@12379
   113
fun gen_symmetric get_sym = Drule.rule_attribute (fn x => fn th =>
wenzelm@12379
   114
  (case Seq.chop (2, Method.multi_resolves [th] (get_sym x)) of
wenzelm@12379
   115
    ([th'], _) => th'
wenzelm@12379
   116
  | ([], _) => raise THM ("symmetric: no unifiers", 1, [th])
wenzelm@12379
   117
  | _ => raise THM ("symmetric: multiple unifiers", 1, [th])));
wenzelm@12379
   118
wenzelm@12379
   119
val symmetric_global = gen_symmetric (#2 o GlobalCalculation.get);
wenzelm@12379
   120
val symmetric_local = gen_symmetric (#2 o #1 o LocalCalculation.get);
wenzelm@6778
   121
wenzelm@6778
   122
wenzelm@6778
   123
(* concrete syntax *)
wenzelm@6778
   124
wenzelm@6778
   125
val trans_attr =
wenzelm@8634
   126
 (Attrib.add_del_args trans_add_global trans_del_global,
wenzelm@8634
   127
  Attrib.add_del_args trans_add_local trans_del_local);
wenzelm@6778
   128
wenzelm@12379
   129
val sym_attr =
wenzelm@12379
   130
 (Attrib.add_del_args sym_add_global sym_del_global,
wenzelm@12379
   131
  Attrib.add_del_args sym_add_local sym_del_local);
wenzelm@12379
   132
wenzelm@15801
   133
val _ = Context.add_setup
wenzelm@15801
   134
 [Attrib.add_attributes
wenzelm@15801
   135
   [("trans", trans_attr, "declaration of transitivity rule"),
wenzelm@15801
   136
    ("sym", sym_attr, "declaration of symmetry rule"),
wenzelm@15801
   137
    ("symmetric", (Attrib.no_args symmetric_global, Attrib.no_args symmetric_local),
wenzelm@15801
   138
      "resolution with symmetry rule")],
wenzelm@15801
   139
  #1 o PureThy.add_thms
wenzelm@15801
   140
   [(("", transitive_thm), [trans_add_global]),
wenzelm@15801
   141
    (("", symmetric_thm), [sym_add_global])]];
wenzelm@15801
   142
wenzelm@6778
   143
wenzelm@6787
   144
wenzelm@6778
   145
(** proof commands **)
wenzelm@6778
   146
wenzelm@14555
   147
fun assert_sane final =
wenzelm@14555
   148
  if final then Proof.assert_forward else Proof.assert_forward_or_chain;
wenzelm@14555
   149
wenzelm@14555
   150
wenzelm@8588
   151
(* maintain calculation register *)
wenzelm@8562
   152
wenzelm@6778
   153
val calculationN = "calculation";
wenzelm@6778
   154
wenzelm@8588
   155
fun maintain_calculation false calc state =
wenzelm@8588
   156
      state
wenzelm@8588
   157
      |> put_calculation calc
wenzelm@14555
   158
      |> Proof.put_thms (calculationN, calc)
wenzelm@8588
   159
  | maintain_calculation true calc state =
wenzelm@8588
   160
      state
wenzelm@8588
   161
      |> reset_calculation
wenzelm@8588
   162
      |> Proof.reset_thms calculationN
wenzelm@14564
   163
      |> Proof.simple_note_thms "" calc
wenzelm@8588
   164
      |> Proof.chain;
wenzelm@8562
   165
wenzelm@8562
   166
wenzelm@8562
   167
(* 'also' and 'finally' *)
wenzelm@8562
   168
wenzelm@8588
   169
fun err_if state b msg = if b then raise Proof.STATE (msg, state) else ();
wenzelm@8588
   170
wenzelm@6877
   171
fun calculate final opt_rules print state =
wenzelm@6778
   172
  let
wenzelm@12805
   173
    val strip_assums_concl = Logic.strip_assums_concl o Thm.prop_of;
wenzelm@9322
   174
    val eq_prop = op aconv o pairself (Pattern.eta_contract o strip_assums_concl);
wenzelm@11097
   175
    fun projection ths th = Library.exists (Library.curry eq_prop th) ths;
wenzelm@8300
   176
wenzelm@11097
   177
    fun combine ths =
skalberg@15531
   178
      (case opt_rules of SOME rules => rules
skalberg@15531
   179
      | NONE =>
wenzelm@12379
   180
          (case ths of [] => NetRules.rules (#1 (get_local_rules state))
wenzelm@12379
   181
          | th :: _ => NetRules.retrieve (#1 (get_local_rules state)) (strip_assums_concl th)))
wenzelm@11097
   182
      |> Seq.of_list |> Seq.map (Method.multi_resolve ths) |> Seq.flat
wenzelm@11097
   183
      |> Seq.filter (not o projection ths);
wenzelm@7414
   184
wenzelm@14555
   185
    val facts = Proof.the_facts (assert_sane final state);
wenzelm@6903
   186
    val (initial, calculations) =
wenzelm@6778
   187
      (case get_calculation state of
skalberg@15531
   188
        NONE => (true, Seq.single facts)
skalberg@15531
   189
      | SOME calc => (false, Seq.map single (combine (calc @ facts))));
wenzelm@6778
   190
  in
wenzelm@8588
   191
    err_if state (initial andalso final) "No calculation yet";
skalberg@15570
   192
    err_if state (initial andalso isSome opt_rules) "Initial calculation -- no rules to be given";
wenzelm@12055
   193
    calculations |> Seq.map (fn calc => (print (Proof.context_of state) calc;
wenzelm@12055
   194
        state |> maintain_calculation final calc))
wenzelm@6778
   195
  end;
wenzelm@6778
   196
wenzelm@6782
   197
fun also print = calculate false print;
wenzelm@6782
   198
fun finally print = calculate true print;
wenzelm@6778
   199
wenzelm@6778
   200
wenzelm@8588
   201
(* 'moreover' and 'ultimately' *)
wenzelm@8562
   202
wenzelm@8588
   203
fun collect final print state =
wenzelm@8588
   204
  let
wenzelm@14555
   205
    val facts = Proof.the_facts (assert_sane final state);
wenzelm@8588
   206
    val (initial, thms) =
wenzelm@8588
   207
      (case get_calculation state of
skalberg@15531
   208
        NONE => (true, [])
skalberg@15531
   209
      | SOME thms => (false, thms));
wenzelm@8588
   210
    val calc = thms @ facts;
wenzelm@8588
   211
  in
wenzelm@8588
   212
    err_if state (initial andalso final) "No calculation yet";
wenzelm@12055
   213
    print (Proof.context_of state) calc;
wenzelm@8588
   214
    state |> maintain_calculation final calc
wenzelm@8588
   215
  end;
wenzelm@8588
   216
wenzelm@8588
   217
fun moreover print = collect false print;
wenzelm@8588
   218
fun ultimately print = collect true print;
wenzelm@8562
   219
wenzelm@8562
   220
wenzelm@6778
   221
end;