krauss@19564: (*  Title:      HOL/Tools/function_package/fundef_package.ML
krauss@19564:     ID:         $Id$
krauss@19564:     Author:     Alexander Krauss, TU Muenchen
krauss@19564: 
krauss@19564: A package for general recursive function definitions. 
krauss@19564: Isar commands.
krauss@19564: 
krauss@19564: *)
krauss@19564: 
krauss@19564: signature FUNDEF_PACKAGE = 
krauss@19564: sig
krauss@19564:     val add_fundef : ((bstring * Attrib.src list) * string) list -> theory -> Proof.state (* Need an _i variant *)
krauss@19564: 
krauss@19564:     val cong_add: attribute
krauss@19564:     val cong_del: attribute
krauss@19564: 							 
krauss@19564:     val setup : theory -> theory
krauss@19564: end
krauss@19564: 
krauss@19564: 
krauss@19564: structure FundefPackage : FUNDEF_PACKAGE =
krauss@19564: struct
krauss@19564: 
krauss@19564: open FundefCommon
krauss@19564: 
krauss@19564: val True_implies = thm "True_implies"
krauss@19564: 
krauss@19564: 
krauss@19564: fun fundef_afterqed congs curry_info name data natts thmss thy =
krauss@19564:     let
krauss@19564: 	val (complete_thm :: compat_thms) = map hd thmss
krauss@19564: 	val fundef_data = FundefProof.mk_partial_rules_curried thy congs curry_info data (freezeT complete_thm) (map freezeT compat_thms)
krauss@19583: 	val FundefResult {psimps, subset_pinduct, simple_pinduct, total_intro, dom_intros, ...} = fundef_data
krauss@19564: 
krauss@19564: 	val (names, attsrcs) = split_list natts
krauss@19564: 	val atts = map (map (Attrib.attribute thy)) attsrcs
krauss@19564: 
krauss@19583: 	val Prep {names = Names {acc_R=accR, ...}, ...} = data
krauss@19583: 	val dom_abbrev = Logic.mk_equals (Free (name ^ "_dom", fastype_of accR), accR)
krauss@19583: 	val (_, thy) = LocalTheory.mapping NONE (Specification.abbreviation_i ("", false) [(NONE, dom_abbrev)]) thy
krauss@19564: 
krauss@19564: 	val thy = thy |> Theory.add_path name 
krauss@19564: 
krauss@19564: 	val thy = thy |> Theory.add_path "psimps"
krauss@19564: 	val (_, thy) = PureThy.add_thms ((names ~~ psimps) ~~ atts) thy;
krauss@19564: 	val thy = thy |> Theory.parent_path
krauss@19564: 
krauss@19564: 	val (_, thy) = PureThy.add_thms [(("cases", complete_thm), [RuleCases.case_names names])] thy
krauss@19564: 	val (_, thy) = PureThy.add_thmss [(("domintros", dom_intros), [])] thy
krauss@19564: 	val (_, thy) = PureThy.add_thms [(("termination", total_intro), [])] thy
krauss@19564: 	val (_,thy) = PureThy.add_thms [(("pinduct", simple_pinduct), [RuleCases.case_names names, InductAttrib.induct_set ""])] thy
krauss@19564: 	val (_, thy) = PureThy.add_thmss [(("psimps", psimps), [Simplifier.simp_add])] thy
krauss@19564: 	val thy = thy |> Theory.parent_path
krauss@19564:     in
krauss@19564: 	add_fundef_data name fundef_data thy
krauss@19564:     end
krauss@19564: 
krauss@19564: fun add_fundef eqns_atts thy =
krauss@19564:     let
krauss@19564: 	val (natts, eqns) = split_list eqns_atts
krauss@19564: 
krauss@19564: 	val congs = get_fundef_congs (Context.Theory thy)
krauss@19564: 
krauss@19564: 	val (curry_info, name, (data, thy)) = FundefPrep.prepare_fundef_curried congs (map (Sign.read_prop thy) eqns) thy
krauss@19583: 	val Prep {complete, compat, ...} = data
krauss@19564: 
krauss@19564: 	val props = (complete :: compat) (*(complete :: fst (chop 110 compat))*)
krauss@19564:     in
krauss@19564: 	thy |> ProofContext.init
krauss@19564: 	    |> Proof.theorem_i PureThy.internalK NONE (fundef_afterqed congs curry_info name data natts) NONE ("", [])
wenzelm@19585: 	    (map (fn t => (("", []), [(t, [])])) props)
krauss@19564:     end
krauss@19564: 
krauss@19564: 
krauss@19564: fun total_termination_afterqed name thmss thy =
krauss@19564:     let
krauss@19564: 	val totality = hd (hd thmss)
krauss@19564: 
krauss@19583: 	val FundefResult {psimps, simple_pinduct, ... }
krauss@19564: 	  = the (get_fundef_data name thy)
krauss@19564: 
krauss@19564: 	val remove_domain_condition = full_simplify (HOL_basic_ss addsimps [totality, True_implies])
krauss@19564: 
krauss@19564: 	val tsimps = map remove_domain_condition psimps
krauss@19564: 	val tinduct = remove_domain_condition simple_pinduct
krauss@19564: 
krauss@19564: 	val thy = Theory.add_path name thy
krauss@19564: 		  
krauss@19564: 		  (* Need the names and attributes. Apply the attributes again? *)
krauss@19564: (*	val thy = thy |> Theory.add_path "simps"
krauss@19564: 	val (_, thy) = PureThy.add_thms ((names ~~ tsimps) ~~ atts) thy;
krauss@19564: 	val thy = thy |> Theory.parent_path*)
krauss@19564: 
krauss@19564: 	val (_, thy) = PureThy.add_thms [(("induct", tinduct), [])] thy 
krauss@19564: 	val (_, thy) = PureThy.add_thmss [(("simps", tsimps), [Simplifier.simp_add, RecfunCodegen.add NONE])] thy
krauss@19564: 	val thy = Theory.parent_path thy
krauss@19564:     in
krauss@19564: 	thy
krauss@19564:     end
krauss@19564: 
krauss@19564: (*
krauss@19564: fun mk_partial_rules name D_name D domT idomT thmss thy =
krauss@19564:     let
krauss@19564: 	val [subs, dcl] = (hd thmss)
krauss@19564: 
krauss@19564: 	val {f_const, f_curried_const, G_const, R_const, G_elims, completeness, f_simps, names_attrs, subset_induct, ... }
krauss@19564: 	  = the (Symtab.lookup (FundefData.get thy) name)
krauss@19564: 
krauss@19564: 	val D_implies_dom = subs COMP (instantiate' [SOME (ctyp_of thy idomT)] 
krauss@19564: 						    [SOME (cterm_of thy D)]
krauss@19564: 						    subsetD)
krauss@19564: 
krauss@19564: 	val D_simps = map (curry op RS D_implies_dom) f_simps
krauss@19564: 
krauss@19564: 	val D_induct = subset_induct
krauss@19564: 			   |> cterm_instantiate [(cterm_of thy (Var (("D",0), fastype_of D)) ,cterm_of thy D)]
krauss@19564: 			   |> curry op COMP subs
krauss@19564: 			   |> curry op COMP (dcl |> forall_intr (cterm_of thy (Var (("z",0), idomT)))
krauss@19564: 						 |> forall_intr (cterm_of thy (Var (("x",0), idomT))))
krauss@19564: 
krauss@19564: 	val ([tinduct'], thy2) = PureThy.add_thms [((name ^ "_" ^ D_name ^ "_induct", D_induct), [])] thy
krauss@19564: 	val ([tsimps'], thy3) = PureThy.add_thmss [((name ^ "_" ^ D_name ^ "_simps", D_simps), [])] thy2
krauss@19564:     in
krauss@19564: 	thy3
krauss@19564:     end
krauss@19564: *)
krauss@19564:  
krauss@19564: 
krauss@19564: fun fundef_setup_termination_proof name NONE thy = 
krauss@19564:     let
krauss@19564: 	val name = if name = "" then get_last_fundef thy else name
krauss@19564: 	val data = the (get_fundef_data name thy)
krauss@19564: 
krauss@19583: 	val FundefResult {total_intro, ...} = data
krauss@19564: 	val goal = FundefTermination.mk_total_termination_goal data
krauss@19564:     in
krauss@19564: 	thy |> ProofContext.init
krauss@19564: 	    |> ProofContext.note_thmss_i [(("termination_intro", 
krauss@19564: 					    [ContextRules.intro_query NONE]), [([total_intro], [])])] |> snd
krauss@19564: 	    |> Proof.theorem_i PureThy.internalK NONE (total_termination_afterqed name) NONE ("", [])
wenzelm@19585: 	    [(("", []), [(goal, [])])]
krauss@19564:     end	
krauss@19564:   | fundef_setup_termination_proof name (SOME (dom_name, dom)) thy =
krauss@19564:     let
krauss@19564: 	val name = if name = "" then get_last_fundef thy else name
krauss@19564: 	val data = the (get_fundef_data name thy)
krauss@19564: 	val (subs, dcl) = FundefTermination.mk_partial_termination_goal thy data dom
krauss@19564:     in
krauss@19564: 	thy |> ProofContext.init
krauss@19564: 	    |> Proof.theorem_i PureThy.internalK NONE (K I) NONE ("", [])
wenzelm@19585: 	    [(("", []), [(subs, []), (dcl, [])])]
krauss@19564:     end	
krauss@19564: 
krauss@19564: 
krauss@19564: 
krauss@19564: 
krauss@19564: (* congruence rules *)
krauss@19564: 
krauss@19564: val cong_add = Thm.declaration_attribute (map_fundef_congs o cons o safe_mk_meta_eq);
krauss@19564: val cong_del = Thm.declaration_attribute (map_fundef_congs o remove (op =) o safe_mk_meta_eq);
krauss@19564: 
krauss@19564: 
krauss@19564: (* setup *)
krauss@19564: 
krauss@19564: val setup = FundefData.init #> FundefCongs.init 
krauss@19564: 	#>  Attrib.add_attributes
krauss@19564: 		[("fundef_cong", Attrib.add_del_args cong_add cong_del, "declaration of congruence rule for function definitions")]
krauss@19564: 
krauss@19564: 
krauss@19564: (* outer syntax *)
krauss@19564: 
krauss@19564: local structure P = OuterParse and K = OuterKeyword in
krauss@19564: 
krauss@19564: val function_decl =
krauss@19564:     Scan.repeat1 (P.opt_thm_name ":" -- P.prop);
krauss@19564: 
krauss@19564: val functionP =
krauss@19564:   OuterSyntax.command "function" "define general recursive functions" K.thy_goal
krauss@19564:     (function_decl >> (fn eqns =>
krauss@19564:       Toplevel.print o Toplevel.theory_to_proof (add_fundef eqns)));
krauss@19564: 
krauss@19564: val terminationP =
krauss@19564:   OuterSyntax.command "termination" "prove termination of a recursive function" K.thy_goal
krauss@19564:   ((Scan.optional P.name "" -- Scan.option (P.$$$ "(" |-- Scan.optional (P.name --| P.$$$ ":") "dom" -- P.term --| P.$$$ ")"))
krauss@19564:        >> (fn (name,dom) =>
krauss@19564: 	      Toplevel.print o Toplevel.theory_to_proof (fundef_setup_termination_proof name dom)));
krauss@19564: 
krauss@19564: val _ = OuterSyntax.add_parsers [functionP];
krauss@19564: val _ = OuterSyntax.add_parsers [terminationP];
krauss@19564: 
krauss@19564: 
krauss@19564: end;
krauss@19564: 
krauss@19564: 
wenzelm@19585: end