wenzelm@5824: (*  Title:      Pure/Isar/method.ML
wenzelm@5824:     ID:         $Id$
wenzelm@5824:     Author:     Markus Wenzel, TU Muenchen
wenzelm@5824: 
wenzelm@5824: Proof methods.
wenzelm@5824: *)
wenzelm@5824: 
wenzelm@5824: signature BASIC_METHOD =
wenzelm@5824: sig
wenzelm@5824:   val print_methods: theory -> unit
wenzelm@5824:   val Method: bstring -> (Args.src -> Proof.context -> Proof.method) -> string -> unit
wenzelm@5824: end;
wenzelm@5824: 
wenzelm@5824: signature METHOD =
wenzelm@5824: sig
wenzelm@5824:   include BASIC_METHOD
wenzelm@5824:   val LIFT: tactic -> thm -> (thm * (indexname * term) list * (string * tthm list) list) Seq.seq
wenzelm@5824:   val METHOD: (tthm list -> tactic) -> Proof.method
wenzelm@5824:   val METHOD0: tactic -> Proof.method
wenzelm@5824:   val fail: Proof.method
wenzelm@5824:   val succeed: Proof.method
wenzelm@5824:   val trivial: Proof.method
wenzelm@5824:   val assumption: Proof.method
wenzelm@5824:   val forward_chain: thm list -> thm list -> thm Seq.seq
wenzelm@5824:   val rule_tac: tthm list -> tthm list -> int -> tactic
wenzelm@5824:   val rule: tthm list -> Proof.method
wenzelm@5824:   val method: theory -> Args.src -> Proof.context -> Proof.method
wenzelm@5824:   val add_methods: (bstring * (Args.src -> Proof.context -> Proof.method) * string) list
wenzelm@5824:     -> theory -> theory
wenzelm@5824:   datatype text =
wenzelm@5824:     Basic of (Proof.context -> Proof.method) |
wenzelm@5824:     Source of Args.src |
wenzelm@5824:     Then of text list |
wenzelm@5824:     Orelse of text list |
wenzelm@5824:     Try of text |
wenzelm@5824:     Repeat of text |
wenzelm@5824:     Repeat1 of text
wenzelm@5824:   val dynamic_method: string -> (Proof.context -> Proof.method)
wenzelm@5824:   val refine: text -> Proof.state -> Proof.state Seq.seq
wenzelm@5824:   val tac: text -> Proof.state -> Proof.state Seq.seq
wenzelm@5824:   val etac: text -> Proof.state -> Proof.state Seq.seq
wenzelm@5824:   val proof: text option -> Proof.state -> Proof.state Seq.seq
wenzelm@5824:   val end_block: Proof.state -> Proof.state Seq.seq
wenzelm@5824:   val terminal_proof: text -> Proof.state -> Proof.state Seq.seq
wenzelm@5824:   val trivial_proof: Proof.state -> Proof.state Seq.seq
wenzelm@5824:   val default_proof: Proof.state -> Proof.state Seq.seq
wenzelm@5824:   val qed: bstring option -> theory attribute list option -> Proof.state
wenzelm@5824:     -> theory * (string * string * tthm)
wenzelm@5824:   val syntax: (Args.T list -> 'a * Args.T list) -> ('a -> 'b) -> Args.src -> 'b
wenzelm@5824:   val no_args: 'a -> Args.src -> Proof.context -> 'a
wenzelm@5824:   val thm_args: (tthm list -> 'a) -> Args.src -> Proof.context -> 'a
wenzelm@5824:   val sectioned_args: (Proof.context -> 'a) -> ('a * tthm list -> 'b) ->
wenzelm@5824:     (string * ('b * tthm list -> 'b)) list -> ('b -> 'c) -> Args.src -> Proof.context -> 'c
wenzelm@5824:   val setup: (theory -> theory) list
wenzelm@5824: end;
wenzelm@5824: 
wenzelm@5824: structure Method: METHOD =
wenzelm@5824: struct
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (** proof methods **)
wenzelm@5824: 
wenzelm@5824: (* method from tactic *)
wenzelm@5824: 
wenzelm@5824: fun LIFT tac goal = Seq.map (fn x => (x, [], [])) (tac goal);
wenzelm@5824: fun METHOD tacf = Proof.method (LIFT o tacf);
wenzelm@5824: fun METHOD0 tac = METHOD (fn [] => tac | _ => error "Method may not be used with facts");
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (* primitive *)
wenzelm@5824: 
wenzelm@5824: val fail = METHOD (K no_tac);
wenzelm@5824: val succeed = METHOD (K all_tac);
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (* trivial, assumption *)
wenzelm@5824: 
wenzelm@5824: fun trivial_tac [] = K all_tac
wenzelm@5824:   | trivial_tac facts =
wenzelm@5824:       let
wenzelm@5824:         val thms = map Attribute.thm_of facts;
wenzelm@5824:         val r = ~ (length facts);
wenzelm@5824:       in metacuts_tac thms THEN' rotate_tac r end;
wenzelm@5824: 
wenzelm@5824: val trivial = METHOD (ALLGOALS o trivial_tac);
wenzelm@5824: val assumption = METHOD (fn facts => FIRSTGOAL (trivial_tac facts THEN' assume_tac));
wenzelm@5824: 
wenzelm@5824: val asm_finish = METHOD (K (TRYALL assume_tac));
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (* rule *)
wenzelm@5824: 
wenzelm@5824: fun res th i rule = Thm.biresolution false [(false, th)] i rule handle THM _ => Seq.empty;
wenzelm@5824: 
wenzelm@5824: fun multi_resolve facts rule =
wenzelm@5824:   let
wenzelm@5824:     fun multi_res i [] = Seq.single rule
wenzelm@5824:       | multi_res i (th :: ths) = Seq.flat (Seq.map (res th i) (multi_res (i + 1) ths))
wenzelm@5824:   in multi_res 1 facts end;
wenzelm@5824: 
wenzelm@5824: fun forward_chain facts rules = Seq.flat (Seq.map (multi_resolve facts) (Seq.of_list rules));
wenzelm@5824: 
wenzelm@5824: fun rule_tac rules [] = resolve_tac (map Attribute.thm_of rules)
wenzelm@5824:   | rule_tac erules facts =
wenzelm@5824:       let
wenzelm@5824:         val rules = forward_chain (map Attribute.thm_of facts) (map Attribute.thm_of erules);
wenzelm@5824:         fun tac i state = Seq.flat (Seq.map (fn rule => Tactic.rtac rule i state) rules);
wenzelm@5824:       in tac end;
wenzelm@5824: 
wenzelm@5824: fun rule rules = METHOD (FIRSTGOAL o rule_tac rules);
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (** methods theory data **)
wenzelm@5824: 
wenzelm@5824: (* data kind 'Isar/methods' *)
wenzelm@5824: 
wenzelm@5824: structure MethodsDataArgs =
wenzelm@5824: struct
wenzelm@5824:   val name = "Isar/methods";
wenzelm@5824:   type T =
wenzelm@5824:     {space: NameSpace.T,
wenzelm@5824:      meths: (((Args.src -> Proof.context -> Proof.method) * string) * stamp) Symtab.table};
wenzelm@5824: 
wenzelm@5824:   val empty = {space = NameSpace.empty, meths = Symtab.empty};
wenzelm@5824:   val prep_ext = I;
wenzelm@5824:   fun merge ({space = space1, meths = meths1}, {space = space2, meths = meths2}) =
wenzelm@5824:     {space = NameSpace.merge (space1, space2),
wenzelm@5824:       meths = Symtab.merge eq_snd (meths1, meths2) handle Symtab.DUPS dups =>
wenzelm@5824:         error ("Attempt to merge different versions of methods " ^ commas_quote dups)};
wenzelm@5824: 
wenzelm@5824:   fun print _ {space, meths} =
wenzelm@5824:     let
wenzelm@5824:       fun prt_meth (name, ((_, comment), _)) = Pretty.block
wenzelm@5824:         [Pretty.str (NameSpace.cond_extern space name ^ ":"), Pretty.brk 2, Pretty.str comment];
wenzelm@5824:     in
wenzelm@5824:       Pretty.writeln (Display.pretty_name_space ("method name space", space));
wenzelm@5824:       Pretty.writeln (Pretty.big_list "methods:" (map prt_meth (Symtab.dest meths)))
wenzelm@5824:     end;
wenzelm@5824: end;
wenzelm@5824: 
wenzelm@5824: structure MethodsData = TheoryDataFun(MethodsDataArgs);
wenzelm@5824: val print_methods = MethodsData.print;
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (* get methods *)
wenzelm@5824: 
wenzelm@5824: fun method thy =
wenzelm@5824:   let
wenzelm@5824:     val {space, meths} = MethodsData.get thy;
wenzelm@5824: 
wenzelm@5824:     fun meth ((raw_name, args), pos) =
wenzelm@5824:       let val name = NameSpace.intern space raw_name in
wenzelm@5824:         (case Symtab.lookup (meths, name) of
wenzelm@5824:           None => error ("Unknown proof method: " ^ quote name ^ Position.str_of pos)
wenzelm@5824:         | Some ((mth, _), _) => mth ((name, args), pos))
wenzelm@5824:       end;
wenzelm@5824:   in meth end;
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (* add_methods *)
wenzelm@5824: 
wenzelm@5824: fun add_methods raw_meths thy =
wenzelm@5824:   let
wenzelm@5824:     val full = Sign.full_name (Theory.sign_of thy);
wenzelm@5824:     val new_meths =
wenzelm@5824:       map (fn (name, f, comment) => (full name, ((f, comment), stamp ()))) raw_meths;
wenzelm@5824: 
wenzelm@5824:     val {space, meths} = MethodsData.get thy;
wenzelm@5824:     val space' = NameSpace.extend (space, map fst new_meths);
wenzelm@5824:     val meths' = Symtab.extend (meths, new_meths) handle Symtab.DUPS dups =>
wenzelm@5824:       error ("Duplicate declaration of method(s) " ^ commas_quote dups);
wenzelm@5824:   in
wenzelm@5824:     thy |> MethodsData.put {space = space', meths = meths'}
wenzelm@5824:   end;
wenzelm@5824: 
wenzelm@5824: (*implicit version*)
wenzelm@5824: fun Method name meth cmt = Context.>> (add_methods [(name, meth, cmt)]);
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (* argument syntax *)
wenzelm@5824: 
wenzelm@5824: val methodN = "method";
wenzelm@5824: fun syntax scan = Args.syntax methodN scan;
wenzelm@5824: 
wenzelm@5824: fun no_args x = syntax (Scan.succeed (fn (_: Proof.context) => x)) I;
wenzelm@5824: 
wenzelm@5824: (* FIXME move? *)
wenzelm@5824: fun thm_args f = syntax (Scan.repeat Args.name)
wenzelm@5824:   (fn names => fn ctxt => f (ProofContext.get_tthmss ctxt names));
wenzelm@5824: 
wenzelm@5824: fun sectioned_args get_data def_sect sects f =
wenzelm@5824:   syntax (Args.sectioned (map fst sects))
wenzelm@5824:     (fn (names, sect_names) => fn ctxt =>
wenzelm@5824:       let
wenzelm@5824:         val get_thms = ProofContext.get_tthmss ctxt;
wenzelm@5824:         val thms = get_thms names;
wenzelm@5824:         val sect_thms = map (apsnd get_thms) sect_names;
wenzelm@5824: 
wenzelm@5824:         fun apply_sect (data, (s, ths)) =
wenzelm@5824:           (case assoc (sects, s) of
wenzelm@5824:             Some add => add (data, ths)
wenzelm@5824:           | None => error ("Unknown argument section " ^ quote s));
wenzelm@5824:        in f (foldl apply_sect (def_sect (get_data ctxt, thms), sect_thms)) end);
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (** method text **)
wenzelm@5824: 
wenzelm@5824: (* datatype text *)
wenzelm@5824: 
wenzelm@5824: datatype text =
wenzelm@5824:   Basic of (Proof.context -> Proof.method) |
wenzelm@5824:   Source of Args.src |
wenzelm@5824:   Then of text list |
wenzelm@5824:   Orelse of text list |
wenzelm@5824:   Try of text |
wenzelm@5824:   Repeat of text |
wenzelm@5824:   Repeat1 of text;
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (* dynamic methods *)
wenzelm@5824: 
wenzelm@5824: fun dynamic_method name = (fn ctxt =>
wenzelm@5824:   method (ProofContext.theory_of ctxt) ((name, []), Position.none) ctxt);
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (* refine *)
wenzelm@5824: 
wenzelm@5824: fun refine text state =
wenzelm@5824:   let
wenzelm@5824:     val thy = Proof.theory_of state;
wenzelm@5824: 
wenzelm@5824:     fun eval (Basic mth) = Proof.refine mth
wenzelm@5824:       | eval (Source src) = Proof.refine (method thy src)
wenzelm@5824:       | eval (Then txts) = Seq.EVERY (map eval txts)
wenzelm@5824:       | eval (Orelse txts) = Seq.FIRST (map eval txts)
wenzelm@5824:       | eval (Try txt) = Seq.TRY (eval txt)
wenzelm@5824:       | eval (Repeat txt) = Seq.REPEAT (eval txt)
wenzelm@5824:       | eval (Repeat1 txt) = Seq.REPEAT1 (eval txt);
wenzelm@5824:   in eval text state end;
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (* unstructured steps *)
wenzelm@5824: 
wenzelm@5824: fun tac text state =
wenzelm@5824:   state
wenzelm@5824:   |> Proof.goal_facts (K [])
wenzelm@5824:   |> refine text;
wenzelm@5824: 
wenzelm@5824: fun etac text state =
wenzelm@5824:   state
wenzelm@5824:   |> Proof.goal_facts Proof.the_facts
wenzelm@5824:   |> refine text;
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (* proof steps *)
wenzelm@5824: 
wenzelm@5824: val default_txt = Source (("default", []), Position.none);
wenzelm@5824: val finishN = "finish";
wenzelm@5824: 
wenzelm@5824: fun proof opt_text state =
wenzelm@5824:   state
wenzelm@5824:   |> Proof.assert_backward
wenzelm@5824:   |> refine (if_none opt_text default_txt)
wenzelm@5824:   |> Seq.map Proof.enter_forward;
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (* conclusions *)
wenzelm@5824: 
wenzelm@5824: val end_block = Proof.end_block (dynamic_method finishN);
wenzelm@5824: 
wenzelm@5824: fun terminal_proof text = Seq.THEN (proof (Some text), end_block);
wenzelm@5824: val trivial_proof = terminal_proof (Basic (K trivial));
wenzelm@5824: val default_proof = terminal_proof default_txt;
wenzelm@5824: 
wenzelm@5824: val qed = Proof.qed (dynamic_method finishN);
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (** theory setup **)
wenzelm@5824: 
wenzelm@5824: (* pure_methods *)
wenzelm@5824: 
wenzelm@5824: val pure_methods =
wenzelm@5824:  [("fail", no_args fail, "force failure"),
wenzelm@5824:   ("succeed", no_args succeed, "succeed"),
wenzelm@5824:   ("trivial", no_args trivial, "proof all goals trivially"),
wenzelm@5824:   ("assumption", no_args assumption, "proof by assumption"),
wenzelm@5824:   ("finish", no_args asm_finish, "finish proof by assumption"),
wenzelm@5824:   ("rule", thm_args rule, "apply primitive rule")];
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: (* setup *)
wenzelm@5824: 
wenzelm@5824: val setup = [MethodsData.init, add_methods pure_methods];
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: end;
wenzelm@5824: 
wenzelm@5824: 
wenzelm@5824: structure BasicMethod: BASIC_METHOD = Method;
wenzelm@5824: open BasicMethod;