src/HOL/Tools/function_package/fundef_package.ML
author krauss
Fri May 05 17:17:21 2006 +0200 (2006-05-05)
changeset 19564 d3e2f532459a
child 19583 c5fa77b03442
permissions -rw-r--r--
First usable version of the new function definition package (HOL/function_packake/...).
Moved Accessible_Part.thy from Library to Main.
     1 (*  Title:      HOL/Tools/function_package/fundef_package.ML
     2     ID:         $Id$
     3     Author:     Alexander Krauss, TU Muenchen
     4 
     5 A package for general recursive function definitions. 
     6 Isar commands.
     7 
     8 *)
     9 
    10 signature FUNDEF_PACKAGE = 
    11 sig
    12     val add_fundef : ((bstring * Attrib.src list) * string) list -> theory -> Proof.state (* Need an _i variant *)
    13 
    14     val cong_add: attribute
    15     val cong_del: attribute
    16 							 
    17     val setup : theory -> theory
    18 end
    19 
    20 
    21 structure FundefPackage : FUNDEF_PACKAGE =
    22 struct
    23 
    24 open FundefCommon
    25 
    26 val True_implies = thm "True_implies"
    27 
    28 
    29 (*#> FundefTermination.setup #> FundefDatatype.setup*)
    30 
    31 fun fundef_afterqed congs curry_info name data natts thmss thy =
    32     let
    33 	val (complete_thm :: compat_thms) = map hd thmss
    34 	val fundef_data = FundefProof.mk_partial_rules_curried thy congs curry_info data (freezeT complete_thm) (map freezeT compat_thms)
    35 	val {psimps, subset_pinduct, simple_pinduct, total_intro, dom_intros, ...} = fundef_data
    36 
    37 	val (names, attsrcs) = split_list natts
    38 	val atts = map (map (Attrib.attribute thy)) attsrcs
    39 
    40 	val accR = (#acc_R(#names(data)))
    41 	val dom_abbrev = Logic.mk_equals (Free ("dom", fastype_of accR), accR)
    42 
    43 	val thy = thy |> Theory.add_path name 
    44 
    45 	val thy = thy |> Theory.add_path "psimps"
    46 	val (_, thy) = PureThy.add_thms ((names ~~ psimps) ~~ atts) thy;
    47 	val thy = thy |> Theory.parent_path
    48 
    49 	val (_, thy) = LocalTheory.mapping NONE (Specification.abbreviation_i ("", false) [(NONE, dom_abbrev)]) thy
    50 	val (_, thy) = PureThy.add_thms [(("cases", complete_thm), [RuleCases.case_names names])] thy
    51 	val (_, thy) = PureThy.add_thmss [(("domintros", dom_intros), [])] thy
    52 	val (_, thy) = PureThy.add_thms [(("termination", total_intro), [])] thy
    53 	val (_,thy) = PureThy.add_thms [(("pinduct", simple_pinduct), [RuleCases.case_names names, InductAttrib.induct_set ""])] thy
    54 	val (_, thy) = PureThy.add_thmss [(("psimps", psimps), [Simplifier.simp_add])] thy
    55 	val thy = thy |> Theory.parent_path
    56     in
    57 	add_fundef_data name fundef_data thy
    58     end
    59 
    60 fun add_fundef eqns_atts thy =
    61     let
    62 	val (natts, eqns) = split_list eqns_atts
    63 
    64 	val congs = get_fundef_congs (Context.Theory thy)
    65 
    66 	val (curry_info, name, (data, thy)) = FundefPrep.prepare_fundef_curried congs (map (Sign.read_prop thy) eqns) thy
    67 	val {complete, compat, ...} = data
    68 
    69 	val props = (complete :: compat) (*(complete :: fst (chop 110 compat))*)
    70     in
    71 	thy |> ProofContext.init
    72 	    |> Proof.theorem_i PureThy.internalK NONE (fundef_afterqed congs curry_info name data natts) NONE ("", [])
    73 	    (map (fn t => (("", []), [(t, ([], []))])) props)
    74     end
    75 
    76 
    77 fun total_termination_afterqed name thmss thy =
    78     let
    79 	val totality = hd (hd thmss)
    80 
    81 	val {psimps, simple_pinduct, ... }
    82 	  = the (get_fundef_data name thy)
    83 
    84 	val remove_domain_condition = full_simplify (HOL_basic_ss addsimps [totality, True_implies])
    85 
    86 	val tsimps = map remove_domain_condition psimps
    87 	val tinduct = remove_domain_condition simple_pinduct
    88 
    89 	val thy = Theory.add_path name thy
    90 		  
    91 		  (* Need the names and attributes. Apply the attributes again? *)
    92 (*	val thy = thy |> Theory.add_path "simps"
    93 	val (_, thy) = PureThy.add_thms ((names ~~ tsimps) ~~ atts) thy;
    94 	val thy = thy |> Theory.parent_path*)
    95 
    96 	val (_, thy) = PureThy.add_thms [(("induct", tinduct), [])] thy 
    97 	val (_, thy) = PureThy.add_thmss [(("simps", tsimps), [Simplifier.simp_add, RecfunCodegen.add NONE])] thy
    98 	val thy = Theory.parent_path thy
    99     in
   100 	thy
   101     end
   102 
   103 (*
   104 fun mk_partial_rules name D_name D domT idomT thmss thy =
   105     let
   106 	val [subs, dcl] = (hd thmss)
   107 
   108 	val {f_const, f_curried_const, G_const, R_const, G_elims, completeness, f_simps, names_attrs, subset_induct, ... }
   109 	  = the (Symtab.lookup (FundefData.get thy) name)
   110 
   111 	val D_implies_dom = subs COMP (instantiate' [SOME (ctyp_of thy idomT)] 
   112 						    [SOME (cterm_of thy D)]
   113 						    subsetD)
   114 
   115 	val D_simps = map (curry op RS D_implies_dom) f_simps
   116 
   117 	val D_induct = subset_induct
   118 			   |> cterm_instantiate [(cterm_of thy (Var (("D",0), fastype_of D)) ,cterm_of thy D)]
   119 			   |> curry op COMP subs
   120 			   |> curry op COMP (dcl |> forall_intr (cterm_of thy (Var (("z",0), idomT)))
   121 						 |> forall_intr (cterm_of thy (Var (("x",0), idomT))))
   122 
   123 	val ([tinduct'], thy2) = PureThy.add_thms [((name ^ "_" ^ D_name ^ "_induct", D_induct), [])] thy
   124 	val ([tsimps'], thy3) = PureThy.add_thmss [((name ^ "_" ^ D_name ^ "_simps", D_simps), [])] thy2
   125     in
   126 	thy3
   127     end
   128 *)
   129  
   130 
   131 fun fundef_setup_termination_proof name NONE thy = 
   132     let
   133 	val name = if name = "" then get_last_fundef thy else name
   134 	val data = the (get_fundef_data name thy)
   135 
   136 	val {total_intro, ...} = data
   137 	val goal = FundefTermination.mk_total_termination_goal data
   138     in
   139 	thy |> ProofContext.init
   140 	    |> ProofContext.note_thmss_i [(("termination_intro", 
   141 					    [ContextRules.intro_query NONE]), [([total_intro], [])])] |> snd
   142 	    |> Proof.theorem_i PureThy.internalK NONE (total_termination_afterqed name) NONE ("", [])
   143 	    [(("", []), [(goal, ([], []))])]
   144     end	
   145   | fundef_setup_termination_proof name (SOME (dom_name, dom)) thy =
   146     let
   147 	val name = if name = "" then get_last_fundef thy else name
   148 	val data = the (get_fundef_data name thy)
   149 	val (subs, dcl) = FundefTermination.mk_partial_termination_goal thy data dom
   150     in
   151 	thy |> ProofContext.init
   152 	    |> Proof.theorem_i PureThy.internalK NONE (K I) NONE ("", [])
   153 	    [(("", []), [(subs, ([], [])), (dcl, ([], []))])]
   154     end	
   155 
   156 
   157 
   158 
   159 (* congruence rules *)
   160 
   161 val cong_add = Thm.declaration_attribute (map_fundef_congs o cons o safe_mk_meta_eq);
   162 val cong_del = Thm.declaration_attribute (map_fundef_congs o remove (op =) o safe_mk_meta_eq);
   163 
   164 
   165 (* setup *)
   166 
   167 val setup = FundefData.init #> FundefCongs.init 
   168 	#>  Attrib.add_attributes
   169 		[("fundef_cong", Attrib.add_del_args cong_add cong_del, "declaration of congruence rule for function definitions")]
   170 
   171 
   172 (* outer syntax *)
   173 
   174 local structure P = OuterParse and K = OuterKeyword in
   175 
   176 val function_decl =
   177     Scan.repeat1 (P.opt_thm_name ":" -- P.prop);
   178 
   179 val functionP =
   180   OuterSyntax.command "function" "define general recursive functions" K.thy_goal
   181     (function_decl >> (fn eqns =>
   182       Toplevel.print o Toplevel.theory_to_proof (add_fundef eqns)));
   183 
   184 val terminationP =
   185   OuterSyntax.command "termination" "prove termination of a recursive function" K.thy_goal
   186   ((Scan.optional P.name "" -- Scan.option (P.$$$ "(" |-- Scan.optional (P.name --| P.$$$ ":") "dom" -- P.term --| P.$$$ ")"))
   187        >> (fn (name,dom) =>
   188 	      Toplevel.print o Toplevel.theory_to_proof (fundef_setup_termination_proof name dom)));
   189 
   190 val _ = OuterSyntax.add_parsers [functionP];
   191 val _ = OuterSyntax.add_parsers [terminationP];
   192 
   193 
   194 end;
   195 
   196 
   197 end