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author | 2010-07-21 09:46:51 +0200 | |
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committer | 2010-07-21 09:46:51 +0200 | |
commit | 5b7eafd0f00a16d78f99a27f5c7d5a0de77dc7e6 (patch) | |
tree | 631ad791a7685edafeb1fb2e8faeedc8379318ae /contrib/funind/invfun.ml | |
parent | da178a880e3ace820b41d38b191d3785b82991f5 (diff) |
Imported Upstream snapshot 8.3~beta0+13298
Diffstat (limited to 'contrib/funind/invfun.ml')
-rw-r--r-- | contrib/funind/invfun.ml | 1022 |
1 files changed, 0 insertions, 1022 deletions
diff --git a/contrib/funind/invfun.ml b/contrib/funind/invfun.ml deleted file mode 100644 index 5c8f0871..00000000 --- a/contrib/funind/invfun.ml +++ /dev/null @@ -1,1022 +0,0 @@ -(************************************************************************) -(* v * The Coq Proof Assistant / The Coq Development Team *) -(* <O___,, * CNRS-Ecole Polytechnique-INRIA Futurs-Universite Paris Sud *) -(* \VV/ **************************************************************) -(* // * This file is distributed under the terms of the *) -(* * GNU Lesser General Public License Version 2.1 *) -(************************************************************************) -open Tacexpr -open Declarations -open Util -open Names -open Term -open Pp -open Libnames -open Tacticals -open Tactics -open Indfun_common -open Tacmach -open Termops -open Sign -open Hiddentac - -(* Some pretty printing function for debugging purpose *) - -let pr_binding prc = - function - | loc, Rawterm.NamedHyp id, (_,c) -> hov 1 (Ppconstr.pr_id id ++ str " := " ++ Pp.cut () ++ prc c) - | loc, Rawterm.AnonHyp n, (_,c) -> hov 1 (int n ++ str " := " ++ Pp.cut () ++ prc c) - -let pr_bindings prc prlc = function - | Rawterm.ImplicitBindings l -> - brk (1,1) ++ str "with" ++ brk (1,1) ++ - Util.prlist_with_sep spc (fun (_,c) -> prc c) l - | Rawterm.ExplicitBindings l -> - brk (1,1) ++ str "with" ++ brk (1,1) ++ - Util.prlist_with_sep spc (fun b -> str"(" ++ pr_binding prlc b ++ str")") l - | Rawterm.NoBindings -> mt () - - -let pr_with_bindings prc prlc (c,bl) = - prc c ++ hv 0 (pr_bindings prc prlc bl) - - - -let pr_constr_with_binding prc (c,bl) : Pp.std_ppcmds = - pr_with_bindings prc prc (c,bl) - -(* The local debuging mechanism *) -let msgnl = Pp.msgnl - -let observe strm = - if do_observe () - then Pp.msgnl strm - else () - -let observennl strm = - if do_observe () - then begin Pp.msg strm;Pp.pp_flush () end - else () - - -let do_observe_tac s tac g = - let goal = begin try (Printer.pr_goal (sig_it g)) with _ -> assert false end in - try - let v = tac g in msgnl (goal ++ fnl () ++ s ++(str " ")++(str "finished")); v - with e -> - msgnl (str "observation "++ s++str " raised exception " ++ - Cerrors.explain_exn e ++ str " on goal " ++ goal ); - raise e;; - - -let observe_tac s tac g = - if do_observe () - then do_observe_tac (str s) tac g - else tac g - -(* [nf_zeta] $\zeta$-normalization of a term *) -let nf_zeta = - Reductionops.clos_norm_flags (Closure.RedFlags.mkflags [Closure.RedFlags.fZETA]) - Environ.empty_env - Evd.empty - - -(* [id_to_constr id] finds the term associated to [id] in the global environment *) -let id_to_constr id = - try - Tacinterp.constr_of_id (Global.env ()) id - with Not_found -> - raise (UserError ("",str "Cannot find " ++ Ppconstr.pr_id id)) - -(* [generate_type g_to_f f graph i] build the completeness (resp. correctness) lemma type if [g_to_f = true] - (resp. g_to_f = false) where [graph] is the graph of [f] and is the [i]th function in the block. - - [generate_type true f i] returns - \[\forall (x_1:t_1)\ldots(x_n:t_n), let fv := f x_1\ldots x_n in, forall res, - graph\ x_1\ldots x_n\ res \rightarrow res = fv \] decomposed as the context and the conclusion - - [generate_type false f i] returns - \[\forall (x_1:t_1)\ldots(x_n:t_n), let fv := f x_1\ldots x_n in, forall res, - res = fv \rightarrow graph\ x_1\ldots x_n\ res\] decomposed as the context and the conclusion - *) - -let generate_type g_to_f f graph i = - (*i we deduce the number of arguments of the function and its returned type from the graph i*) - let graph_arity = Inductive.type_of_inductive (Global.env()) (Global.lookup_inductive (destInd graph)) in - let ctxt,_ = decompose_prod_assum graph_arity in - let fun_ctxt,res_type = - match ctxt with - | [] | [_] -> anomaly "Not a valid context" - | (_,_,res_type)::fun_ctxt -> fun_ctxt,res_type - in - let nb_args = List.length fun_ctxt in - let args_from_decl i decl = - match decl with - | (_,Some _,_) -> incr i; failwith "args_from_decl" - | _ -> let j = !i in incr i;mkRel (nb_args - j + 1) - in - (*i We need to name the vars [res] and [fv] i*) - let res_id = - Termops.next_global_ident_away - true - (id_of_string "res") - (map_succeed (function (Name id,_,_) -> id | (Anonymous,_,_) -> failwith "") fun_ctxt) - in - let fv_id = - Termops.next_global_ident_away - true - (id_of_string "fv") - (res_id::(map_succeed (function (Name id,_,_) -> id | (Anonymous,_,_) -> failwith "Anonymous!") fun_ctxt)) - in - (*i we can then type the argument to be applied to the function [f] i*) - let args_as_rels = - let i = ref 0 in - Array.of_list ((map_succeed (args_from_decl i) (List.rev fun_ctxt))) - in - let args_as_rels = Array.map Termops.pop args_as_rels in - (*i - the hypothesis [res = fv] can then be computed - We will need to lift it by one in order to use it as a conclusion - i*) - let res_eq_f_of_args = - mkApp(Coqlib.build_coq_eq (),[|lift 2 res_type;mkRel 1;mkRel 2|]) - in - (*i - The hypothesis [graph\ x_1\ldots x_n\ res] can then be computed - We will need to lift it by one in order to use it as a conclusion - i*) - let graph_applied = - let args_and_res_as_rels = - let i = ref 0 in - Array.of_list ((map_succeed (args_from_decl i) (List.rev ((Name res_id,None,res_type)::fun_ctxt))) ) - in - let args_and_res_as_rels = - Array.mapi (fun i c -> if i <> Array.length args_and_res_as_rels - 1 then lift 1 c else c) args_and_res_as_rels - in - mkApp(graph,args_and_res_as_rels) - in - (*i The [pre_context] is the defined to be the context corresponding to - \[\forall (x_1:t_1)\ldots(x_n:t_n), let fv := f x_1\ldots x_n in, forall res, \] - i*) - let pre_ctxt = - (Name res_id,None,lift 1 res_type)::(Name fv_id,Some (mkApp(mkConst f,args_as_rels)),res_type)::fun_ctxt - in - (*i and we can return the solution depending on which lemma type we are defining i*) - if g_to_f - then (Anonymous,None,graph_applied)::pre_ctxt,(lift 1 res_eq_f_of_args) - else (Anonymous,None,res_eq_f_of_args)::pre_ctxt,(lift 1 graph_applied) - - -(* - [find_induction_principle f] searches and returns the [body] and the [type] of [f_rect] - - WARNING: while convertible, [type_of body] and [type] can be non equal -*) -let find_induction_principle f = - let f_as_constant = match kind_of_term f with - | Const c' -> c' - | _ -> error "Must be used with a function" - in - let infos = find_Function_infos f_as_constant in - match infos.rect_lemma with - | None -> raise Not_found - | Some rect_lemma -> - let rect_lemma = mkConst rect_lemma in - let typ = Typing.type_of (Global.env ()) Evd.empty rect_lemma in - rect_lemma,typ - - - -(* let fname = *) -(* match kind_of_term f with *) -(* | Const c' -> *) -(* id_of_label (con_label c') *) -(* | _ -> error "Must be used with a function" *) -(* in *) - -(* let princ_name = *) -(* ( *) -(* Indrec.make_elimination_ident *) -(* fname *) -(* InType *) -(* ) *) -(* in *) -(* let c = (\* mkConst(mk_from_const (destConst f) princ_name ) in *\) failwith "" in *) -(* c,Typing.type_of (Global.env ()) Evd.empty c *) - - -let rec generate_fresh_id x avoid i = - if i == 0 - then [] - else - let id = Termops.next_global_ident_away true x avoid in - id::(generate_fresh_id x (id::avoid) (pred i)) - - -(* [prove_fun_correct functional_induction funs_constr graphs_constr schemes lemmas_types_infos i ] - is the tactic used to prove correctness lemma. - - [functional_induction] is the tactic defined in [indfun] (dependency problem) - [funs_constr], [graphs_constr] [schemes] [lemmas_types_infos] are the mutually recursive functions - (resp. graphs of the functions and principles and correctness lemma types) to prove correct. - - [i] is the indice of the function to prove correct - - The lemma to prove if suppose to have been generated by [generate_type] (in $\zeta$ normal form that is - it looks like~: - [\forall (x_1:t_1)\ldots(x_n:t_n), forall res, - res = f x_1\ldots x_n in, \rightarrow graph\ x_1\ldots x_n\ res] - - - The sketch of the proof is the following one~: - \begin{enumerate} - \item intros until $x_n$ - \item $functional\ induction\ (f.(i)\ x_1\ldots x_n)$ using schemes.(i) - \item for each generated branch intro [res] and [hres :res = f x_1\ldots x_n], rewrite [hres] and the - apply the corresponding constructor of the corresponding graph inductive. - \end{enumerate} - -*) -let prove_fun_correct functional_induction funs_constr graphs_constr schemes lemmas_types_infos i : tactic = - fun g -> - (* first of all we recreate the lemmas types to be used as predicates of the induction principle - that is~: - \[fun (x_1:t_1)\ldots(x_n:t_n)=> fun fv => fun res => res = fv \rightarrow graph\ x_1\ldots x_n\ res\] - *) - let lemmas = - Array.map - (fun (_,(ctxt,concl)) -> - match ctxt with - | [] | [_] | [_;_] -> anomaly "bad context" - | hres::res::(x,_,t)::ctxt -> - Termops.it_mkLambda_or_LetIn - ~init:(Termops.it_mkProd_or_LetIn ~init:concl [hres;res]) - ((x,None,t)::ctxt) - ) - lemmas_types_infos - in - (* we the get the definition of the graphs block *) - let graph_ind = destInd graphs_constr.(i) in - let kn = fst graph_ind in - let mib,_ = Global.lookup_inductive graph_ind in - (* and the principle to use in this lemma in $\zeta$ normal form *) - let f_principle,princ_type = schemes.(i) in - let princ_type = nf_zeta princ_type in - let princ_infos = Tactics.compute_elim_sig princ_type in - (* The number of args of the function is then easilly computable *) - let nb_fun_args = nb_prod (pf_concl g) - 2 in - let args_names = generate_fresh_id (id_of_string "x") [] nb_fun_args in - let ids = args_names@(pf_ids_of_hyps g) in - (* Since we cannot ensure that the funcitonnal principle is defined in the - environement and due to the bug #1174, we will need to pose the principle - using a name - *) - let principle_id = Termops.next_global_ident_away true (id_of_string "princ") ids in - let ids = principle_id :: ids in - (* We get the branches of the principle *) - let branches = List.rev princ_infos.branches in - (* and built the intro pattern for each of them *) - let intro_pats = - List.map - (fun (_,_,br_type) -> - List.map - (fun id -> dummy_loc, Genarg.IntroIdentifier id) - (generate_fresh_id (id_of_string "y") ids (List.length (fst (decompose_prod_assum br_type)))) - ) - branches - in - (* before building the full intro pattern for the principle *) - let pat = Some (dummy_loc,Genarg.IntroOrAndPattern intro_pats) in - let eq_ind = Coqlib.build_coq_eq () in - let eq_construct = mkConstruct((destInd eq_ind),1) in - (* The next to referencies will be used to find out which constructor to apply in each branch *) - let ind_number = ref 0 - and min_constr_number = ref 0 in - (* The tactic to prove the ith branch of the principle *) - let prove_branche i g = - (* We get the identifiers of this branch *) - let this_branche_ids = - List.fold_right - (fun (_,pat) acc -> - match pat with - | Genarg.IntroIdentifier id -> Idset.add id acc - | _ -> anomaly "Not an identifier" - ) - (List.nth intro_pats (pred i)) - Idset.empty - in - (* and get the real args of the branch by unfolding the defined constant *) - let pre_args,pre_tac = - List.fold_right - (fun (id,b,t) (pre_args,pre_tac) -> - if Idset.mem id this_branche_ids - then - match b with - | None -> (id::pre_args,pre_tac) - | Some b -> - (pre_args, - tclTHEN (h_reduce (Rawterm.Unfold([Rawterm.all_occurrences_expr,EvalVarRef id])) allHyps) pre_tac - ) - - else (pre_args,pre_tac) - ) - (pf_hyps g) - ([],tclIDTAC) - in - (* - We can then recompute the arguments of the constructor. - For each [hid] introduced by this branch, if [hid] has type - $forall res, res=fv -> graph.(j)\ x_1\ x_n res$ the corresponding arguments of the constructor are - [ fv (hid fv (refl_equal fv)) ]. - - If [hid] has another type the corresponding argument of the constructor is [hid] - *) - let constructor_args = - List.fold_right - (fun hid acc -> - let type_of_hid = pf_type_of g (mkVar hid) in - match kind_of_term type_of_hid with - | Prod(_,_,t') -> - begin - match kind_of_term t' with - | Prod(_,t'',t''') -> - begin - match kind_of_term t'',kind_of_term t''' with - | App(eq,args), App(graph',_) - when - (eq_constr eq eq_ind) && - array_exists (eq_constr graph') graphs_constr -> - ((mkApp(mkVar hid,[|args.(2);(mkApp(eq_construct,[|args.(0);args.(2)|]))|])) - ::args.(2)::acc) - | _ -> mkVar hid :: acc - end - | _ -> mkVar hid :: acc - end - | _ -> mkVar hid :: acc - ) pre_args [] - in - (* in fact we must also add the parameters to the constructor args *) - let constructor_args = - let params_id = fst (list_chop princ_infos.nparams args_names) in - (List.map mkVar params_id)@(List.rev constructor_args) - in - (* We then get the constructor corresponding to this branch and - modifies the references has needed i.e. - if the constructor is the last one of the current inductive then - add one the number of the inductive to take and add the number of constructor of the previous - graph to the minimal constructor number - *) - let constructor = - let constructor_num = i - !min_constr_number in - let length = Array.length (mib.Declarations.mind_packets.(!ind_number).Declarations.mind_consnames) in - if constructor_num <= length - then - begin - (kn,!ind_number),constructor_num - end - else - begin - incr ind_number; - min_constr_number := !min_constr_number + length ; - (kn,!ind_number),1 - end - in - (* we can then build the final proof term *) - let app_constructor = applist((mkConstruct(constructor)),constructor_args) in - (* an apply the tactic *) - let res,hres = - match generate_fresh_id (id_of_string "z") (ids(* @this_branche_ids *)) 2 with - | [res;hres] -> res,hres - | _ -> assert false - in - observe (str "constructor := " ++ Printer.pr_lconstr_env (pf_env g) app_constructor); - ( - tclTHENSEQ - [ - (* unfolding of all the defined variables introduced by this branch *) - observe_tac "unfolding" pre_tac; - (* $zeta$ normalizing of the conclusion *) - h_reduce - (Rawterm.Cbv - { Rawterm.all_flags with - Rawterm.rDelta = false ; - Rawterm.rConst = [] - } - ) - onConcl; - (* introducing the the result of the graph and the equality hypothesis *) - observe_tac "introducing" (tclMAP h_intro [res;hres]); - (* replacing [res] with its value *) - observe_tac "rewriting res value" (Equality.rewriteLR (mkVar hres)); - (* Conclusion *) - observe_tac "exact" (h_exact app_constructor) - ] - ) - g - in - (* end of branche proof *) - let param_names = fst (list_chop princ_infos.nparams args_names) in - let params = List.map mkVar param_names in - let lemmas = Array.to_list (Array.map (fun c -> applist(c,params)) lemmas) in - (* The bindings of the principle - that is the params of the principle and the different lemma types - *) - let bindings = - let params_bindings,avoid = - List.fold_left2 - (fun (bindings,avoid) (x,_,_) p -> - let id = Nameops.next_ident_away (Nameops.out_name x) avoid in - (dummy_loc,Rawterm.NamedHyp id,inj_open p)::bindings,id::avoid - ) - ([],pf_ids_of_hyps g) - princ_infos.params - (List.rev params) - in - let lemmas_bindings = - List.rev (fst (List.fold_left2 - (fun (bindings,avoid) (x,_,_) p -> - let id = Nameops.next_ident_away (Nameops.out_name x) avoid in - (dummy_loc,Rawterm.NamedHyp id,inj_open (nf_zeta p))::bindings,id::avoid) - ([],avoid) - princ_infos.predicates - (lemmas))) - in - Rawterm.ExplicitBindings (params_bindings@lemmas_bindings) - in - tclTHENSEQ - [ observe_tac "intro args_names" (tclMAP h_intro args_names); - observe_tac "principle" (assert_by - (Name principle_id) - princ_type - (h_exact f_principle)); - tclTHEN_i - (observe_tac "functional_induction" ( - fun g -> - observe - (pr_constr_with_binding (Printer.pr_lconstr_env (pf_env g)) (mkVar principle_id,bindings)); - functional_induction false (applist(funs_constr.(i),List.map mkVar args_names)) - (Some (mkVar principle_id,bindings)) - pat g - )) - (fun i g -> observe_tac ("proving branche "^string_of_int i) (prove_branche i) g ) - ] - g - -(* [generalize_dependent_of x hyp g] - generalize every hypothesis which depends of [x] but [hyp] -*) -let generalize_dependent_of x hyp g = - tclMAP - (function - | (id,None,t) when not (id = hyp) && - (Termops.occur_var (pf_env g) x t) -> tclTHEN (h_generalize [mkVar id]) (thin [id]) - | _ -> tclIDTAC - ) - (pf_hyps g) - g - - - - - - (* [intros_with_rewrite] do the intros in each branch and treat each new hypothesis - (unfolding, substituting, destructing cases \ldots) - *) -let rec intros_with_rewrite g = - observe_tac "intros_with_rewrite" intros_with_rewrite_aux g -and intros_with_rewrite_aux : tactic = - fun g -> - let eq_ind = Coqlib.build_coq_eq () in - match kind_of_term (pf_concl g) with - | Prod(_,t,t') -> - begin - match kind_of_term t with - | App(eq,args) when (eq_constr eq eq_ind) -> - if Reductionops.is_conv (pf_env g) (project g) args.(1) args.(2) - then - let id = pf_get_new_id (id_of_string "y") g in - tclTHENSEQ [ h_intro id; thin [id]; intros_with_rewrite ] g - - else if isVar args.(1) - then - let id = pf_get_new_id (id_of_string "y") g in - tclTHENSEQ [ h_intro id; - generalize_dependent_of (destVar args.(1)) id; - tclTRY (Equality.rewriteLR (mkVar id)); - intros_with_rewrite - ] - g - else - begin - let id = pf_get_new_id (id_of_string "y") g in - tclTHENSEQ[ - h_intro id; - tclTRY (Equality.rewriteLR (mkVar id)); - intros_with_rewrite - ] g - end - | Ind _ when eq_constr t (Coqlib.build_coq_False ()) -> - Tauto.tauto g - | Case(_,_,v,_) -> - tclTHENSEQ[ - h_case false (v,Rawterm.NoBindings); - intros_with_rewrite - ] g - | LetIn _ -> - tclTHENSEQ[ - h_reduce - (Rawterm.Cbv - {Rawterm.all_flags - with Rawterm.rDelta = false; - }) - onConcl - ; - intros_with_rewrite - ] g - | _ -> - let id = pf_get_new_id (id_of_string "y") g in - tclTHENSEQ [ h_intro id;intros_with_rewrite] g - end - | LetIn _ -> - tclTHENSEQ[ - h_reduce - (Rawterm.Cbv - {Rawterm.all_flags - with Rawterm.rDelta = false; - }) - onConcl - ; - intros_with_rewrite - ] g - | _ -> tclIDTAC g - -let rec reflexivity_with_destruct_cases g = - let destruct_case () = - try - match kind_of_term (snd (destApp (pf_concl g))).(2) with - | Case(_,_,v,_) -> - tclTHENSEQ[ - h_case false (v,Rawterm.NoBindings); - intros; - observe_tac "reflexivity_with_destruct_cases" reflexivity_with_destruct_cases - ] - | _ -> reflexivity - with _ -> reflexivity - in - let eq_ind = Coqlib.build_coq_eq () in - let discr_inject = - Tacticals.onAllClauses ( - fun sc g -> - match sc with - None -> tclIDTAC g - | Some ((_,id),_) -> - match kind_of_term (pf_type_of g (mkVar id)) with - | App(eq,[|_;t1;t2|]) when eq_constr eq eq_ind -> - if Equality.discriminable (pf_env g) (project g) t1 t2 - then Equality.discrHyp id g - else if Equality.injectable (pf_env g) (project g) t1 t2 - then tclTHENSEQ [Equality.injHyp id;thin [id];intros_with_rewrite] g - else tclIDTAC g - | _ -> tclIDTAC g - ) - in - (tclFIRST - [ reflexivity; - tclTHEN (tclPROGRESS discr_inject) (destruct_case ()); - (* We reach this point ONLY if - the same value is matched (at least) two times - along binding path. - In this case, either we have a discriminable hypothesis and we are done, - either at least an injectable one and we do the injection before continuing - *) - tclTHEN (tclPROGRESS discr_inject ) reflexivity_with_destruct_cases - ]) - g - - -(* [prove_fun_complete funs graphs schemes lemmas_types_infos i] - is the tactic used to prove completness lemma. - - [funcs], [graphs] [schemes] [lemmas_types_infos] are the mutually recursive functions - (resp. definitions of the graphs of the functions, principles and correctness lemma types) to prove correct. - - [i] is the indice of the function to prove complete - - The lemma to prove if suppose to have been generated by [generate_type] (in $\zeta$ normal form that is - it looks like~: - [\forall (x_1:t_1)\ldots(x_n:t_n), forall res, - graph\ x_1\ldots x_n\ res, \rightarrow res = f x_1\ldots x_n in] - - - The sketch of the proof is the following one~: - \begin{enumerate} - \item intros until $H:graph\ x_1\ldots x_n\ res$ - \item $elim\ H$ using schemes.(i) - \item for each generated branch, intro the news hyptohesis, for each such hyptohesis [h], if [h] has - type [x=?] with [x] a variable, then subst [x], - if [h] has type [t=?] with [t] not a variable then rewrite [t] in the subterms, else - if [h] is a match then destruct it, else do just introduce it, - after all intros, the conclusion should be a reflexive equality. - \end{enumerate} - -*) - - -let prove_fun_complete funcs graphs schemes lemmas_types_infos i : tactic = - fun g -> - (* We compute the types of the different mutually recursive lemmas - in $\zeta$ normal form - *) - let lemmas = - Array.map - (fun (_,(ctxt,concl)) -> nf_zeta (Termops.it_mkLambda_or_LetIn ~init:concl ctxt)) - lemmas_types_infos - in - (* We get the constant and the principle corresponding to this lemma *) - let f = funcs.(i) in - let graph_principle = nf_zeta schemes.(i) in - let princ_type = pf_type_of g graph_principle in - let princ_infos = Tactics.compute_elim_sig princ_type in - (* Then we get the number of argument of the function - and compute a fresh name for each of them - *) - let nb_fun_args = nb_prod (pf_concl g) - 2 in - let args_names = generate_fresh_id (id_of_string "x") [] nb_fun_args in - let ids = args_names@(pf_ids_of_hyps g) in - (* and fresh names for res H and the principle (cf bug bug #1174) *) - let res,hres,graph_principle_id = - match generate_fresh_id (id_of_string "z") ids 3 with - | [res;hres;graph_principle_id] -> res,hres,graph_principle_id - | _ -> assert false - in - let ids = res::hres::graph_principle_id::ids in - (* we also compute fresh names for each hyptohesis of each branche of the principle *) - let branches = List.rev princ_infos.branches in - let intro_pats = - List.map - (fun (_,_,br_type) -> - List.map - (fun id -> id) - (generate_fresh_id (id_of_string "y") ids (nb_prod br_type)) - ) - branches - in - (* We will need to change the function by its body - using [f_equation] if it is recursive (that is the graph is infinite - or unfold if the graph is finite - *) - let rewrite_tac j ids : tactic = - let graph_def = graphs.(j) in - let infos = try find_Function_infos (destConst funcs.(j)) with Not_found -> error "No graph found" in - if infos.is_general || Rtree.is_infinite graph_def.mind_recargs - then - let eq_lemma = - try Option.get (infos).equation_lemma - with Option.IsNone -> anomaly "Cannot find equation lemma" - in - tclTHENSEQ[ - tclMAP h_intro ids; - Equality.rewriteLR (mkConst eq_lemma); - (* Don't forget to $\zeta$ normlize the term since the principles have been $\zeta$-normalized *) - h_reduce - (Rawterm.Cbv - {Rawterm.all_flags - with Rawterm.rDelta = false; - }) - onConcl - ; - h_generalize (List.map mkVar ids); - thin ids - ] - else unfold_in_concl [(all_occurrences,Names.EvalConstRef (destConst f))] - in - (* The proof of each branche itself *) - let ind_number = ref 0 in - let min_constr_number = ref 0 in - let prove_branche i g = - (* we fist compute the inductive corresponding to the branch *) - let this_ind_number = - let constructor_num = i - !min_constr_number in - let length = Array.length (graphs.(!ind_number).Declarations.mind_consnames) in - if constructor_num <= length - then !ind_number - else - begin - incr ind_number; - min_constr_number := !min_constr_number + length; - !ind_number - end - in - let this_branche_ids = List.nth intro_pats (pred i) in - tclTHENSEQ[ - (* we expand the definition of the function *) - observe_tac "rewrite_tac" (rewrite_tac this_ind_number this_branche_ids); - (* introduce hypothesis with some rewrite *) - observe_tac "intros_with_rewrite" intros_with_rewrite; - (* The proof is (almost) complete *) - observe_tac "reflexivity" (reflexivity_with_destruct_cases) - ] - g - in - let params_names = fst (list_chop princ_infos.nparams args_names) in - let params = List.map mkVar params_names in - tclTHENSEQ - [ tclMAP h_intro (args_names@[res;hres]); - observe_tac "h_generalize" - (h_generalize [mkApp(applist(graph_principle,params),Array.map (fun c -> applist(c,params)) lemmas)]); - h_intro graph_principle_id; - observe_tac "" (tclTHEN_i - (observe_tac "elim" ((elim false (mkVar hres,Rawterm.NoBindings) (Some (mkVar graph_principle_id,Rawterm.NoBindings))))) - (fun i g -> observe_tac "prove_branche" (prove_branche i) g )) - ] - g - - - - -let do_save () = Command.save_named false - - -(* [derive_correctness make_scheme functional_induction funs graphs] create correctness and completeness - lemmas for each function in [funs] w.r.t. [graphs] - - [make_scheme] is Functional_principle_types.make_scheme (dependency pb) and - [functional_induction] is Indfun.functional_induction (same pb) -*) - -let derive_correctness make_scheme functional_induction (funs: constant list) (graphs:inductive list) = - let funs = Array.of_list funs and graphs = Array.of_list graphs in - let funs_constr = Array.map mkConst funs in - try - let graphs_constr = Array.map mkInd graphs in - let lemmas_types_infos = - Util.array_map2_i - (fun i f_constr graph -> - let const_of_f = destConst f_constr in - let (type_of_lemma_ctxt,type_of_lemma_concl) as type_info = - generate_type false const_of_f graph i - in - let type_of_lemma = Termops.it_mkProd_or_LetIn ~init:type_of_lemma_concl type_of_lemma_ctxt in - let type_of_lemma = nf_zeta type_of_lemma in - observe (str "type_of_lemma := " ++ Printer.pr_lconstr type_of_lemma); - type_of_lemma,type_info - ) - funs_constr - graphs_constr - in - let schemes = - (* The functional induction schemes are computed and not saved if there is more that one function - if the block contains only one function we can safely reuse [f_rect] - *) - try - if Array.length funs_constr <> 1 then raise Not_found; - [| find_induction_principle funs_constr.(0) |] - with Not_found -> - Array.of_list - (List.map - (fun entry -> - (entry.Entries.const_entry_body, Option.get entry.Entries.const_entry_type ) - ) - (make_scheme (array_map_to_list (fun const -> const,Rawterm.RType None) funs)) - ) - in - let proving_tac = - prove_fun_correct functional_induction funs_constr graphs_constr schemes lemmas_types_infos - in - Array.iteri - (fun i f_as_constant -> - let f_id = id_of_label (con_label f_as_constant) in - Command.start_proof - (*i The next call to mk_correct_id is valid since we are constructing the lemma - Ensures by: obvious - i*) - (mk_correct_id f_id) - (Decl_kinds.Global,(Decl_kinds.Proof Decl_kinds.Theorem)) - (fst lemmas_types_infos.(i)) - (fun _ _ -> ()); - Pfedit.by (observe_tac ("prove correctness ("^(string_of_id f_id)^")") (proving_tac i)); - do_save (); - let finfo = find_Function_infos f_as_constant in - update_Function - {finfo with - correctness_lemma = Some (destConst (Tacinterp.constr_of_id (Global.env ())(mk_correct_id f_id))) - } - - ) - funs; - let lemmas_types_infos = - Util.array_map2_i - (fun i f_constr graph -> - let const_of_f = destConst f_constr in - let (type_of_lemma_ctxt,type_of_lemma_concl) as type_info = - generate_type true const_of_f graph i - in - let type_of_lemma = Termops.it_mkProd_or_LetIn ~init:type_of_lemma_concl type_of_lemma_ctxt in - let type_of_lemma = nf_zeta type_of_lemma in - observe (str "type_of_lemma := " ++ Printer.pr_lconstr type_of_lemma); - type_of_lemma,type_info - ) - funs_constr - graphs_constr - in - let kn,_ as graph_ind = destInd graphs_constr.(0) in - let mib,mip = Global.lookup_inductive graph_ind in - let schemes = - Array.of_list - (Indrec.build_mutual_indrec (Global.env ()) Evd.empty - (Array.to_list - (Array.mapi - (fun i mip -> (kn,i),mib,mip,true,InType) - mib.Declarations.mind_packets - ) - ) - ) - in - let proving_tac = - prove_fun_complete funs_constr mib.Declarations.mind_packets schemes lemmas_types_infos - in - Array.iteri - (fun i f_as_constant -> - let f_id = id_of_label (con_label f_as_constant) in - Command.start_proof - (*i The next call to mk_complete_id is valid since we are constructing the lemma - Ensures by: obvious - i*) - (mk_complete_id f_id) - (Decl_kinds.Global,(Decl_kinds.Proof Decl_kinds.Theorem)) - (fst lemmas_types_infos.(i)) - (fun _ _ -> ()); - Pfedit.by (observe_tac ("prove completeness ("^(string_of_id f_id)^")") (proving_tac i)); - do_save (); - let finfo = find_Function_infos f_as_constant in - update_Function - {finfo with - completeness_lemma = Some (destConst (Tacinterp.constr_of_id (Global.env ())(mk_complete_id f_id))) - } - ) - funs; - with e -> - (* In case of problem, we reset all the lemmas *) - (*i The next call to mk_correct_id is valid since we are erasing the lemmas - Ensures by: obvious - i*) - let first_lemma_id = - let f_id = id_of_label (con_label funs.(0)) in - - mk_correct_id f_id - in - ignore(try Vernacentries.vernac_reset_name (Util.dummy_loc,first_lemma_id) with _ -> ()); - raise e - - - - - -(***********************************************) - -(* [revert_graph kn post_tac hid] transforme an hypothesis [hid] having type Ind(kn,num) t1 ... tn res - when [kn] denotes a graph block into - f_num t1... tn = res (by applying [f_complete] to the first type) before apply post_tac on the result - - if the type of hypothesis has not this form or if we cannot find the completeness lemma then we do nothing -*) -let revert_graph kn post_tac hid g = - let typ = pf_type_of g (mkVar hid) in - match kind_of_term typ with - | App(i,args) when isInd i -> - let ((kn',num) as ind') = destInd i in - if kn = kn' - then (* We have generated a graph hypothesis so that we must change it if we can *) - let info = - try find_Function_of_graph ind' - with Not_found -> (* The graphs are mutually recursive but we cannot find one of them !*) - anomaly "Cannot retrieve infos about a mutual block" - in - (* if we can find a completeness lemma for this function - then we can come back to the functional form. If not, we do nothing - *) - match info.completeness_lemma with - | None -> tclIDTAC g - | Some f_complete -> - let f_args,res = array_chop (Array.length args - 1) args in - tclTHENSEQ - [ - h_generalize [applist(mkConst f_complete,(Array.to_list f_args)@[res.(0);mkVar hid])]; - thin [hid]; - h_intro hid; - post_tac hid - ] - g - - else tclIDTAC g - | _ -> tclIDTAC g - - -(* - [functional_inversion hid fconst f_correct ] is the functional version of [inversion] - - [hid] is the hypothesis to invert, [fconst] is the function to invert and [f_correct] - is the correctness lemma for [fconst]. - - The sketch is the follwing~: - \begin{enumerate} - \item Transforms the hypothesis [hid] such that its type is now $res\ =\ f\ t_1 \ldots t_n$ - (fails if it is not possible) - \item replace [hid] with $R\_f t_1 \ldots t_n res$ using [f_correct] - \item apply [inversion] on [hid] - \item finally in each branch, replace each hypothesis [R\_f ..] by [f ...] using [f_complete] (whenever - such a lemma exists) - \end{enumerate} -*) - -let functional_inversion kn hid fconst f_correct : tactic = - fun g -> - let old_ids = List.fold_right Idset.add (pf_ids_of_hyps g) Idset.empty in - let type_of_h = pf_type_of g (mkVar hid) in - match kind_of_term type_of_h with - | App(eq,args) when eq_constr eq (Coqlib.build_coq_eq ()) -> - let pre_tac,f_args,res = - match kind_of_term args.(1),kind_of_term args.(2) with - | App(f,f_args),_ when eq_constr f fconst -> - ((fun hid -> h_symmetry (onHyp hid)),f_args,args.(2)) - |_,App(f,f_args) when eq_constr f fconst -> - ((fun hid -> tclIDTAC),f_args,args.(1)) - | _ -> (fun hid -> tclFAIL 1 (mt ())),[||],args.(2) - in - tclTHENSEQ[ - pre_tac hid; - h_generalize [applist(f_correct,(Array.to_list f_args)@[res;mkVar hid])]; - thin [hid]; - h_intro hid; - Inv.inv FullInversion None (Rawterm.NamedHyp hid); - (fun g -> - let new_ids = List.filter (fun id -> not (Idset.mem id old_ids)) (pf_ids_of_hyps g) in - tclMAP (revert_graph kn pre_tac) (hid::new_ids) g - ); - ] g - | _ -> tclFAIL 1 (mt ()) g - - - -let invfun qhyp f = - let f = - match f with - | ConstRef f -> f - | _ -> raise (Util.UserError("",str "Not a function")) - in - try - let finfos = find_Function_infos f in - let f_correct = mkConst(Option.get finfos.correctness_lemma) - and kn = fst finfos.graph_ind - in - Tactics.try_intros_until (fun hid -> functional_inversion kn hid (mkConst f) f_correct) qhyp - with - | Not_found -> error "No graph found" - | Option.IsNone -> error "Cannot use equivalence with graph!" - - -let invfun qhyp f g = - match f with - | Some f -> invfun qhyp f g - | None -> - Tactics.try_intros_until - (fun hid g -> - let hyp_typ = pf_type_of g (mkVar hid) in - match kind_of_term hyp_typ with - | App(eq,args) when eq_constr eq (Coqlib.build_coq_eq ()) -> - begin - let f1,_ = decompose_app args.(1) in - try - if not (isConst f1) then failwith ""; - let finfos = find_Function_infos (destConst f1) in - let f_correct = mkConst(Option.get finfos.correctness_lemma) - and kn = fst finfos.graph_ind - in - functional_inversion kn hid f1 f_correct g - with | Failure "" | Option.IsNone | Not_found -> - try - let f2,_ = decompose_app args.(2) in - if not (isConst f2) then failwith ""; - let finfos = find_Function_infos (destConst f2) in - let f_correct = mkConst(Option.get finfos.correctness_lemma) - and kn = fst finfos.graph_ind - in - functional_inversion kn hid f2 f_correct g - with - | Failure "" -> - errorlabstrm "" (str "Hypothesis" ++ Ppconstr.pr_id hid ++ str " must contain at leat one Function") - | Option.IsNone -> - if do_observe () - then - error "Cannot use equivalence with graph for any side of the equality" - else errorlabstrm "" (str "Cannot find inversion information for hypothesis " ++ Ppconstr.pr_id hid) - | Not_found -> - if do_observe () - then - error "No graph found for any side of equality" - else errorlabstrm "" (str "Cannot find inversion information for hypothesis " ++ Ppconstr.pr_id hid) - end - | _ -> errorlabstrm "" (Ppconstr.pr_id hid ++ str " must be an equality ") - ) - qhyp - g |