src/HOL/Tools/function_package/fundef_package.ML
author krauss
Fri Aug 04 18:01:45 2006 +0200 (2006-08-04)
changeset 20338 ecdfc96cf4d0
parent 20320 a5368278a72c
child 20363 f34c5dbe74d5
permissions -rw-r--r--
Added Keywords: "otherwise" and "sequential", needed for function package's
sequential mode.
krauss@20270
     1
krauss@19564
     2
(*  Title:      HOL/Tools/function_package/fundef_package.ML
krauss@19564
     3
    ID:         $Id$
krauss@19564
     4
    Author:     Alexander Krauss, TU Muenchen
krauss@19564
     5
krauss@19564
     6
A package for general recursive function definitions. 
krauss@19564
     7
Isar commands.
krauss@19564
     8
krauss@19564
     9
*)
krauss@19564
    10
krauss@19564
    11
signature FUNDEF_PACKAGE = 
krauss@19564
    12
sig
krauss@20270
    13
    val add_fundef : ((bstring * (Attrib.src list * bool)) * string) list list -> bool -> theory -> Proof.state (* Need an _i variant *)
krauss@19564
    14
krauss@19564
    15
    val cong_add: attribute
krauss@19564
    16
    val cong_del: attribute
krauss@19564
    17
							 
krauss@19564
    18
    val setup : theory -> theory
krauss@19770
    19
    val get_congs : theory -> thm list
krauss@19564
    20
end
krauss@19564
    21
krauss@19564
    22
krauss@19564
    23
structure FundefPackage : FUNDEF_PACKAGE =
krauss@19564
    24
struct
krauss@19564
    25
krauss@19564
    26
open FundefCommon
krauss@19564
    27
krauss@19564
    28
krauss@20270
    29
fun add_simps label moreatts (MutualPart {f_name, ...}, psimps) spec_part thy =
krauss@19770
    30
    let 
krauss@20270
    31
      val psimpss = Library.unflat (map snd spec_part) psimps
krauss@20270
    32
      val (names, attss) = split_list (map fst spec_part) 
krauss@20270
    33
krauss@19770
    34
      val thy = thy |> Theory.add_path f_name 
krauss@19770
    35
                
krauss@19770
    36
      val thy = thy |> Theory.add_path label
krauss@20270
    37
      val spsimpss = map (map standard) psimpss (* FIXME *)
krauss@20270
    38
      val add_list = (names ~~ spsimpss) ~~ attss
krauss@20270
    39
      val (_, thy) = PureThy.add_thmss add_list thy
krauss@19770
    40
      val thy = thy |> Theory.parent_path
krauss@19770
    41
                
krauss@20270
    42
      val (_, thy) = PureThy.add_thmss [((label, flat spsimpss), Simplifier.simp_add :: moreatts)] thy
krauss@19770
    43
      val thy = thy |> Theory.parent_path
krauss@19770
    44
    in
krauss@19770
    45
      thy
krauss@19770
    46
    end
krauss@19770
    47
    
krauss@19770
    48
krauss@19770
    49
krauss@19770
    50
krauss@19770
    51
krauss@19770
    52
krauss@20270
    53
fun fundef_afterqed congs mutual_info name data spec [[result]] thy =
krauss@19564
    54
    let
krauss@19922
    55
	val fundef_data = FundefMutual.mk_partial_rules_mutual thy mutual_info data result
krauss@19922
    56
	val FundefMResult {psimps, subset_pinducts, simple_pinducts, termination, domintros, cases, ...} = fundef_data
krauss@19922
    57
        val Mutual {parts, ...} = mutual_info
krauss@19564
    58
krauss@19583
    59
	val Prep {names = Names {acc_R=accR, ...}, ...} = data
krauss@19583
    60
	val dom_abbrev = Logic.mk_equals (Free (name ^ "_dom", fastype_of accR), accR)
krauss@19583
    61
	val (_, thy) = LocalTheory.mapping NONE (Specification.abbreviation_i ("", false) [(NONE, dom_abbrev)]) thy
krauss@19564
    62
krauss@20270
    63
        val thy = fold2 (add_simps "psimps" []) (parts ~~ psimps) spec thy
krauss@20270
    64
krauss@20270
    65
        val casenames = flat (map (map (fst o fst)) spec)
krauss@19564
    66
krauss@19770
    67
	val thy = thy |> Theory.add_path name
krauss@20270
    68
	val (_, thy) = PureThy.add_thms [(("cases", cases), [RuleCases.case_names casenames])] thy
krauss@19770
    69
	val (_, thy) = PureThy.add_thmss [(("domintros", domintros), [])] thy
krauss@19922
    70
	val (_, thy) = PureThy.add_thms [(("termination", standard termination), [])] thy
krauss@20270
    71
	val (_,thy) = PureThy.add_thmss [(("pinduct", map standard simple_pinducts), [RuleCases.case_names casenames, InductAttrib.induct_set ""])] thy
krauss@19564
    72
	val thy = thy |> Theory.parent_path
krauss@19564
    73
    in
krauss@20270
    74
      add_fundef_data name (fundef_data, mutual_info, spec) thy
krauss@19564
    75
    end
krauss@19564
    76
krauss@20285
    77
fun gen_add_fundef prep_att eqns_attss (preprocess : bool) thy =
krauss@19564
    78
    let
krauss@20270
    79
      fun prep_eqns neqs =
krauss@20270
    80
          neqs
krauss@20270
    81
            |> map (apsnd (Sign.read_prop thy))    
krauss@20270
    82
            |> map (apfst (apsnd (apfst (map (prep_att thy)))))
krauss@20270
    83
            |> FundefSplit.split_some_equations (ProofContext.init thy)
krauss@20270
    84
      
krauss@20270
    85
      val spec = map prep_eqns eqns_attss
krauss@20270
    86
      val t_eqnss = map (flat o map snd) spec
krauss@19770
    87
krauss@20270
    88
      val congs = get_fundef_congs (Context.Theory thy)
krauss@19564
    89
krauss@20270
    90
      val (mutual_info, name, (data, thy)) = FundefMutual.prepare_fundef_mutual congs t_eqnss thy
krauss@20270
    91
      val Prep {goal, goalI, ...} = data
krauss@19564
    92
    in
krauss@19564
    93
	thy |> ProofContext.init
krauss@20270
    94
	    |> Proof.theorem_i PureThy.internalK NONE (fundef_afterqed congs mutual_info name data spec) NONE ("", [])
krauss@19922
    95
	    [(("", []), [(goal, [])])]
krauss@19922
    96
            |> Proof.refine (Method.primitive_text (fn _ => goalI))
krauss@19922
    97
            |> Seq.hd
krauss@19564
    98
    end
krauss@19564
    99
krauss@19564
   100
krauss@19770
   101
fun total_termination_afterqed name (Mutual {parts, ...}) thmss thy =
krauss@19564
   102
    let
krauss@19564
   103
	val totality = hd (hd thmss)
krauss@19564
   104
krauss@20270
   105
	val (FundefMResult {psimps, simple_pinducts, ... }, Mutual {parts, ...}, spec)
krauss@19564
   106
	  = the (get_fundef_data name thy)
krauss@19564
   107
wenzelm@20320
   108
	val remove_domain_condition = full_simplify (HOL_basic_ss addsimps [totality, True_implies_equals])
krauss@19564
   109
krauss@19770
   110
	val tsimps = map (map remove_domain_condition) psimps
krauss@19770
   111
	val tinduct = map remove_domain_condition simple_pinducts
krauss@19770
   112
krauss@19784
   113
        val has_guards = exists ((fn (Const ("Trueprop", _) $ _) => false | _ => true) o prop_of) (flat tsimps)
krauss@19784
   114
        val allatts = if has_guards then [] else [RecfunCodegen.add NONE]
krauss@19784
   115
krauss@20270
   116
        val thy = fold2 (add_simps "simps" allatts) (parts ~~ tsimps) spec thy
krauss@19564
   117
krauss@19564
   118
	val thy = Theory.add_path name thy
krauss@19564
   119
		  
krauss@19770
   120
	val (_, thy) = PureThy.add_thmss [(("induct", map standard tinduct), [])] thy 
krauss@19564
   121
	val thy = Theory.parent_path thy
krauss@19564
   122
    in
krauss@19564
   123
	thy
krauss@19564
   124
    end
krauss@19564
   125
krauss@19564
   126
(*
krauss@19564
   127
fun mk_partial_rules name D_name D domT idomT thmss thy =
krauss@19564
   128
    let
krauss@19564
   129
	val [subs, dcl] = (hd thmss)
krauss@19564
   130
krauss@19564
   131
	val {f_const, f_curried_const, G_const, R_const, G_elims, completeness, f_simps, names_attrs, subset_induct, ... }
krauss@19564
   132
	  = the (Symtab.lookup (FundefData.get thy) name)
krauss@19564
   133
krauss@19564
   134
	val D_implies_dom = subs COMP (instantiate' [SOME (ctyp_of thy idomT)] 
krauss@19564
   135
						    [SOME (cterm_of thy D)]
krauss@19564
   136
						    subsetD)
krauss@19564
   137
krauss@19564
   138
	val D_simps = map (curry op RS D_implies_dom) f_simps
krauss@19564
   139
krauss@19564
   140
	val D_induct = subset_induct
krauss@19564
   141
			   |> cterm_instantiate [(cterm_of thy (Var (("D",0), fastype_of D)) ,cterm_of thy D)]
krauss@19564
   142
			   |> curry op COMP subs
krauss@19564
   143
			   |> curry op COMP (dcl |> forall_intr (cterm_of thy (Var (("z",0), idomT)))
krauss@19564
   144
						 |> forall_intr (cterm_of thy (Var (("x",0), idomT))))
krauss@19564
   145
krauss@19564
   146
	val ([tinduct'], thy2) = PureThy.add_thms [((name ^ "_" ^ D_name ^ "_induct", D_induct), [])] thy
krauss@19564
   147
	val ([tsimps'], thy3) = PureThy.add_thmss [((name ^ "_" ^ D_name ^ "_simps", D_simps), [])] thy2
krauss@19564
   148
    in
krauss@19564
   149
	thy3
krauss@19564
   150
    end
krauss@19564
   151
*)
krauss@19564
   152
 
krauss@19564
   153
krauss@19564
   154
fun fundef_setup_termination_proof name NONE thy = 
krauss@19564
   155
    let
krauss@19564
   156
	val name = if name = "" then get_last_fundef thy else name
krauss@19564
   157
	val data = the (get_fundef_data name thy)
krauss@19938
   158
                   handle Option.Option => raise ERROR ("No such function definition: " ^ name)
krauss@19564
   159
krauss@20270
   160
	val (res as FundefMResult {termination, ...}, mutual, _) = data
krauss@19564
   161
	val goal = FundefTermination.mk_total_termination_goal data
krauss@19564
   162
    in
krauss@19564
   163
	thy |> ProofContext.init
krauss@19770
   164
	    |> ProofContext.note_thmss_i [(("termination", 
krauss@19922
   165
					    [ContextRules.intro_query NONE]), [([standard termination], [])])] |> snd
krauss@19770
   166
	    |> Proof.theorem_i PureThy.internalK NONE (total_termination_afterqed name mutual) NONE ("", [])
wenzelm@19585
   167
	    [(("", []), [(goal, [])])]
krauss@19564
   168
    end	
krauss@19564
   169
  | fundef_setup_termination_proof name (SOME (dom_name, dom)) thy =
krauss@19564
   170
    let
krauss@19564
   171
	val name = if name = "" then get_last_fundef thy else name
krauss@19564
   172
	val data = the (get_fundef_data name thy)
krauss@19564
   173
	val (subs, dcl) = FundefTermination.mk_partial_termination_goal thy data dom
krauss@19564
   174
    in
krauss@19564
   175
	thy |> ProofContext.init
krauss@19564
   176
	    |> Proof.theorem_i PureThy.internalK NONE (K I) NONE ("", [])
wenzelm@19585
   177
	    [(("", []), [(subs, []), (dcl, [])])]
krauss@19564
   178
    end	
krauss@19564
   179
krauss@19564
   180
krauss@19611
   181
val add_fundef = gen_add_fundef Attrib.attribute
krauss@19611
   182
krauss@19564
   183
krauss@19564
   184
krauss@19564
   185
(* congruence rules *)
krauss@19564
   186
wenzelm@19617
   187
val cong_add = Thm.declaration_attribute (map_fundef_congs o Drule.add_rule o safe_mk_meta_eq);
wenzelm@19617
   188
val cong_del = Thm.declaration_attribute (map_fundef_congs o Drule.del_rule o safe_mk_meta_eq);
krauss@19564
   189
krauss@19564
   190
krauss@19564
   191
(* setup *)
krauss@19564
   192
krauss@19564
   193
val setup = FundefData.init #> FundefCongs.init 
krauss@19564
   194
	#>  Attrib.add_attributes
krauss@19564
   195
		[("fundef_cong", Attrib.add_del_args cong_add cong_del, "declaration of congruence rule for function definitions")]
krauss@19564
   196
krauss@19564
   197
krauss@19770
   198
val get_congs = FundefCommon.get_fundef_congs o Context.Theory
krauss@19770
   199
krauss@19770
   200
krauss@19564
   201
(* outer syntax *)
krauss@19564
   202
krauss@19564
   203
local structure P = OuterParse and K = OuterKeyword in
krauss@19564
   204
krauss@20270
   205
krauss@20270
   206
krauss@20270
   207
val star = Scan.one (fn t => (OuterLex.val_of t = "*"));
krauss@20270
   208
krauss@20270
   209
krauss@20270
   210
val attribs_with_star = P.$$$ "[" |-- P.!!! ((P.list (star >> K NONE || P.attrib >> SOME)) 
krauss@20270
   211
                                               >> (fn x => (map_filter I x, exists is_none x)))
krauss@20270
   212
                              --| P.$$$ "]";
krauss@20270
   213
krauss@20270
   214
val opt_attribs_with_star = Scan.optional attribs_with_star ([], false);
krauss@20270
   215
krauss@20338
   216
val opt_thm_name_star =
krauss@20338
   217
  Scan.optional ((P.name -- opt_attribs_with_star || (attribs_with_star >> pair "")) --| P.$$$ ":") ("", ([], false));
krauss@20270
   218
krauss@20270
   219
krauss@19564
   220
val function_decl =
krauss@20338
   221
    Scan.repeat1 (opt_thm_name_star -- P.prop);
krauss@19564
   222
krauss@19564
   223
val functionP =
krauss@19564
   224
  OuterSyntax.command "function" "define general recursive functions" K.thy_goal
krauss@20338
   225
  (((Scan.optional (P.$$$ "(" -- P.!!! (P.$$$ "sequential" -- P.$$$ ")") >> K true) false) --    
krauss@20270
   226
  P.and_list1 function_decl) >> (fn (prepr, eqnss) =>
krauss@20270
   227
                                    Toplevel.print o Toplevel.theory_to_proof (add_fundef eqnss prepr)));
krauss@19564
   228
krauss@19564
   229
val terminationP =
krauss@19564
   230
  OuterSyntax.command "termination" "prove termination of a recursive function" K.thy_goal
krauss@19564
   231
  ((Scan.optional P.name "" -- Scan.option (P.$$$ "(" |-- Scan.optional (P.name --| P.$$$ ":") "dom" -- P.term --| P.$$$ ")"))
krauss@19564
   232
       >> (fn (name,dom) =>
krauss@19564
   233
	      Toplevel.print o Toplevel.theory_to_proof (fundef_setup_termination_proof name dom)));
krauss@19564
   234
krauss@20338
   235
val _ = OuterSyntax.add_keywords ["sequential", "otherwise"];
krauss@20338
   236
krauss@19564
   237
val _ = OuterSyntax.add_parsers [functionP];
krauss@19564
   238
val _ = OuterSyntax.add_parsers [terminationP];
krauss@19564
   239
krauss@19564
   240
krauss@19564
   241
end;
krauss@19564
   242
krauss@19564
   243
wenzelm@19585
   244
end