src/Pure/Isar/object_logic.ML
author haftmann
Fri Nov 10 07:44:47 2006 +0100 (2006-11-10)
changeset 21286 b5e7b80caa6a
parent 20912 380663e636a8
child 21687 f689f729afab
permissions -rw-r--r--
introduces canonical AList functions for loop_tacs
     1 (*  Title:      Pure/Isar/object_logic.ML
     2     ID:         $Id$
     3     Author:     Markus Wenzel, TU Muenchen
     4 
     5 Specifics about common object-logics.
     6 *)
     7 
     8 signature OBJECT_LOGIC =
     9 sig
    10   val add_judgment: bstring * string * mixfix -> theory -> theory
    11   val add_judgment_i: bstring * typ * mixfix -> theory -> theory
    12   val judgment_name: theory -> string
    13   val is_judgment: theory -> term -> bool
    14   val drop_judgment: theory -> term -> term
    15   val fixed_judgment: theory -> string -> term
    16   val ensure_propT: theory -> term -> term
    17   val is_elim: thm -> bool
    18   val declare_atomize: attribute
    19   val declare_rulify: attribute
    20   val atomize_term: theory -> term -> term
    21   val atomize_cterm: cterm -> thm
    22   val atomize_thm: thm -> thm
    23   val atomize_tac: int -> tactic
    24   val full_atomize_tac: int -> tactic
    25   val atomize_goal: int -> thm -> thm
    26   val rulify_term: theory -> term -> term
    27   val rulify_tac: int -> tactic
    28   val rulify: thm -> thm
    29   val rulify_no_asm: thm -> thm
    30   val rule_format: attribute
    31   val rule_format_no_asm: attribute
    32 end;
    33 
    34 structure ObjectLogic: OBJECT_LOGIC =
    35 struct
    36 
    37 
    38 (** theory data **)
    39 
    40 structure ObjectLogicData = TheoryDataFun
    41 (struct
    42   val name = "Pure/object_logic";
    43   type T = string option * (thm list * thm list);
    44 
    45   val empty = (NONE, ([], [Drule.norm_hhf_eq]));
    46   val copy = I;
    47   val extend = I;
    48 
    49   fun merge_judgment (SOME x, SOME y) =
    50         if x = y then SOME x else error "Attempt to merge different object-logics"
    51     | merge_judgment (j1, j2) = if is_some j1 then j1 else j2;
    52 
    53   fun merge _ ((judgment1, (atomize1, rulify1)), (judgment2, (atomize2, rulify2))) =
    54     (merge_judgment (judgment1, judgment2),
    55       (Drule.merge_rules (atomize1, atomize2), Drule.merge_rules (rulify1, rulify2)));
    56 
    57   fun print _ _ = ();
    58 end);
    59 
    60 val _ = Context.add_setup ObjectLogicData.init;
    61 
    62 
    63 
    64 (** generic treatment of judgments -- with a single argument only **)
    65 
    66 (* add judgment *)
    67 
    68 local
    69 
    70 fun new_judgment name (NONE, rules) = (SOME name, rules)
    71   | new_judgment _ (SOME _, _) = error "Attempt to redeclare object-logic judgment";
    72 
    73 fun gen_add_judgment add_consts (bname, T, mx) thy =
    74   let val c = Sign.full_name thy (Syntax.const_name bname mx) in
    75     thy
    76     |> add_consts [(bname, T, mx)]
    77     |> (fn thy' => Theory.add_finals_i false [(Const (c, Sign.the_const_type thy' c))] thy')
    78     |> ObjectLogicData.map (new_judgment c)
    79   end;
    80 
    81 in
    82 
    83 val add_judgment = gen_add_judgment Theory.add_consts;
    84 val add_judgment_i = gen_add_judgment Theory.add_consts_i;
    85 
    86 end;
    87 
    88 
    89 (* term operations *)
    90 
    91 fun judgment_name thy =
    92   (case ObjectLogicData.get thy of
    93     (SOME name, _) => name
    94   | _ => raise TERM ("Unknown object-logic judgment", []));
    95 
    96 fun is_judgment thy (Const (c, _) $ _) = c = judgment_name thy
    97   | is_judgment _ _ = false;
    98 
    99 fun drop_judgment thy (Abs (x, T, t)) = Abs (x, T, drop_judgment thy t)
   100   | drop_judgment thy (tm as (Const (c, _) $ t)) =
   101       if (c = judgment_name thy handle TERM _ => false) then t else tm
   102   | drop_judgment _ tm = tm;
   103 
   104 fun fixed_judgment thy x =
   105   let  (*be robust wrt. low-level errors*)
   106     val c = judgment_name thy;
   107     val aT = TFree ("'a", []);
   108     val T =
   109       the_default (aT --> propT) (Sign.const_type thy c)
   110       |> Term.map_type_tvar (fn ((x, _), S) => TFree (x, S));
   111     val U = Term.domain_type T handle Match => aT;
   112   in Const (c, T) $ Free (x, U) end;
   113 
   114 fun ensure_propT thy t =
   115   let val T = Term.fastype_of t
   116   in if T = propT then t else Const (judgment_name thy, T --> propT) $ t end;
   117 
   118 
   119 (* elimination rules *)
   120 
   121 fun is_elim rule =
   122   let
   123     val thy = Thm.theory_of_thm rule;
   124     val concl = Thm.concl_of rule;
   125   in
   126     Term.is_Var (drop_judgment thy concl) andalso
   127       exists (fn prem => concl aconv Logic.strip_assums_concl prem) (Thm.prems_of rule)
   128   end;
   129 
   130 
   131 
   132 (** treatment of meta-level connectives **)
   133 
   134 (* maintain rules *)
   135 
   136 val get_atomize = #1 o #2 o ObjectLogicData.get;
   137 val get_rulify = #2 o #2 o ObjectLogicData.get;
   138 
   139 val declare_atomize = Thm.declaration_attribute (fn th =>
   140   Context.mapping (ObjectLogicData.map (apsnd (apfst (Drule.add_rule th)))) I);
   141 
   142 val declare_rulify = Thm.declaration_attribute (fn th =>
   143   Context.mapping (ObjectLogicData.map (apsnd (apsnd (Drule.add_rule th)))) I);
   144 
   145 
   146 (* atomize *)
   147 
   148 fun rewrite_prems_tac rews i = PRIMITIVE (Drule.fconv_rule
   149   (Drule.goals_conv (Library.equal i)
   150     (Drule.forall_conv ~1
   151       (Drule.goals_conv (K true) (Tactic.rewrite true rews)))));
   152 
   153 fun atomize_term thy =
   154   drop_judgment thy o MetaSimplifier.rewrite_term thy (get_atomize thy) [];
   155 
   156 fun atomize_cterm ct = Tactic.rewrite true (get_atomize (Thm.theory_of_cterm ct)) ct;
   157 fun atomize_thm th = rewrite_rule (get_atomize (Thm.theory_of_thm th)) th;
   158 
   159 fun atomize_tac i st =
   160   if Logic.has_meta_prems (Thm.prop_of st) i then
   161     (rewrite_prems_tac (get_atomize (Thm.theory_of_thm st)) i) st
   162   else all_tac st;
   163 
   164 fun full_atomize_tac i st =
   165   rewrite_goal_tac (get_atomize (Thm.theory_of_thm st)) i st;
   166 
   167 fun atomize_goal i st =
   168   (case Seq.pull (atomize_tac i st) of NONE => st | SOME (st', _) => st');
   169 
   170 
   171 (* rulify *)
   172 
   173 fun rulify_term thy = MetaSimplifier.rewrite_term thy (get_rulify thy) [];
   174 fun rulify_tac i st = rewrite_goal_tac (get_rulify (Thm.theory_of_thm st)) i st;
   175 
   176 fun gen_rulify full thm =
   177   Tactic.simplify full (get_rulify (Thm.theory_of_thm thm)) thm
   178   |> Drule.gen_all |> Thm.strip_shyps |> Drule.zero_var_indexes;
   179 
   180 val rulify = gen_rulify true;
   181 val rulify_no_asm = gen_rulify false;
   182 
   183 fun rule_format x = Thm.rule_attribute (fn _ => rulify) x;
   184 fun rule_format_no_asm x = Thm.rule_attribute (fn _ => rulify_no_asm) x;
   185 
   186 end;