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Diffstat (limited to 'plugins/ssr/ssrview.ml')
| -rw-r--r-- | plugins/ssr/ssrview.ml | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/plugins/ssr/ssrview.ml b/plugins/ssr/ssrview.ml new file mode 100644 index 00000000..aa614fbc --- /dev/null +++ b/plugins/ssr/ssrview.ml @@ -0,0 +1,332 @@ +(************************************************************************) +(* * The Coq Proof Assistant / The Coq Development Team *) +(* v * INRIA, CNRS and contributors - Copyright 1999-2018 *) +(* <O___,, * (see CREDITS file for the list of authors) *) +(* \VV/ **************************************************************) +(* // * This file is distributed under the terms of the *) +(* * GNU Lesser General Public License Version 2.1 *) +(* * (see LICENSE file for the text of the license) *) +(************************************************************************) + +open Util +open Names + +open Ltac_plugin + +open Proofview +open Notations + +open Ssrcommon +open Ssrast + +module AdaptorDb = struct + + type kind = Forward | Backward | Equivalence + + module AdaptorKind = struct + type t = kind + let compare = Pervasives.compare + end + module AdaptorMap = Map.Make(AdaptorKind) + + let term_view_adaptor_db = + Summary.ref ~name:"view_adaptor_db" AdaptorMap.empty + + let get k = + try AdaptorMap.find k !term_view_adaptor_db + with Not_found -> [] + + let cache_adaptor (_, (k, t)) = + let lk = get k in + if not (List.exists (Glob_ops.glob_constr_eq t) lk) then + term_view_adaptor_db := AdaptorMap.add k (t :: lk) !term_view_adaptor_db + + let subst_adaptor ( subst, (k, t as a)) = + let t' = Detyping.subst_glob_constr subst t in + if t' == t then a else k, t' + + let classify_adaptor x = Libobject.Substitute x + + let in_db = + Libobject.declare_object { + (Libobject.default_object "VIEW_ADAPTOR_DB") + with + Libobject.open_function = (fun i o -> if i = 1 then cache_adaptor o); + Libobject.cache_function = cache_adaptor; + Libobject.subst_function = subst_adaptor; + Libobject.classify_function = classify_adaptor } + + let declare kind terms = + List.iter (fun term -> Lib.add_anonymous_leaf (in_db (kind,term))) + (List.rev terms) + +end + +(* Forward View application code *****************************************) + +module State : sig + + (* View storage API *) + val vsINIT : EConstr.t -> unit tactic + val vsPUSH : (EConstr.t -> EConstr.t tactic) -> unit tactic + val vsCONSUME : (Id.t option -> EConstr.t -> unit tactic) -> unit tactic + val vsASSERT_EMPTY : unit tactic + +end = struct (* {{{ *) + +type vstate = { + subject_name : Id.t option; (* top *) + (* None if views are being applied to a term *) + view : EConstr.t; (* v2 (v1 top) *) +} + +include Ssrcommon.MakeState(struct + type state = vstate option + let init = None +end) + +let vsINIT view = tclSET (Some { subject_name = None; view }) + +let vsPUSH k = + tacUPDATE (fun s -> match s with + | Some { subject_name; view } -> + k view >>= fun view -> + tclUNIT (Some { subject_name; view }) + | None -> + Goal.enter_one ~__LOC__ begin fun gl -> + let concl = Goal.concl gl in + let id = (* We keep the orig name for checks in "in" tcl *) + match EConstr.kind_of_type (Goal.sigma gl) concl with + | Term.ProdType(Name.Name id, _, _) + when Ssrcommon.is_discharged_id id -> id + | _ -> mk_anon_id "view_subject" (Tacmach.New.pf_ids_of_hyps gl) in + let view = EConstr.mkVar id in + Ssrcommon.tclINTRO_ID id <*> + k view >>= fun view -> + tclUNIT (Some { subject_name = Some id; view }) + end) + +let vsCONSUME k = + tclGET (fun s -> match s with + | Some { subject_name; view } -> + tclSET None <*> + k subject_name view + | None -> anomaly "vsCONSUME: empty storage") + +let vsASSERT_EMPTY = + tclGET (function + | Some _ -> anomaly ("vsASSERT_EMPTY: not empty") + | _ -> tclUNIT ()) + +end (* }}} *) + +let intern_constr_expr { Genintern.genv; ltacvars = vars } sigma ce = + let ltacvars = { + Constrintern.empty_ltac_sign with Constrintern.ltac_vars = vars } in + Constrintern.intern_gen Pretyping.WithoutTypeConstraint ~ltacvars genv sigma ce + +(* Disambiguation of /t + - t is ltac:(tactic args) + - t is a term + To allow for t being a notation, like "Notation foo x := ltac:(foo x)", we + need to internalize t. +*) +let is_tac_in_term { body; glob_env; interp_env } = + Goal.(enter_one ~__LOC__ begin fun goal -> + let genv = env goal in + let sigma = sigma goal in + let ist = Ssrcommon.option_assert_get glob_env (Pp.str"not a term") in + (* We use the env of the goal, not the global one *) + let ist = { ist with Genintern.genv } in + (* We unravel notations *) + let g = intern_constr_expr ist sigma body in + match DAst.get g with + | Glob_term.GHole (_,_, Some x) + when Genarg.has_type x (Genarg.glbwit Tacarg.wit_tactic) + -> tclUNIT (`Tac (Genarg.out_gen (Genarg.glbwit Tacarg.wit_tactic) x)) + | _ -> tclUNIT (`Term (interp_env, g)) +end) + +(* To inject a constr into a glob_constr we use an Ltac variable *) +let tclINJ_CONSTR_IST ist p = + let fresh_id = Ssrcommon.mk_internal_id "ssr_inj_constr_in_glob" in + let ist = { + ist with Geninterp.lfun = + Id.Map.add fresh_id (Taccoerce.Value.of_constr p) ist.Geninterp.lfun} in + tclUNIT (ist,Glob_term.GVar fresh_id) + +let mkGHole = + DAst.make + (Glob_term.GHole(Evar_kinds.InternalHole, Misctypes.IntroAnonymous, None)) +let rec mkGHoles n = if n > 0 then mkGHole :: mkGHoles (n - 1) else [] +let mkGApp f args = + if args = [] then f + else DAst.make (Glob_term.GApp (f, args)) + +(* From glob_constr to open_constr === (env,sigma,constr) *) +let interp_glob ist glob = Goal.enter_one ~__LOC__ begin fun goal -> + let env = Goal.env goal in + let sigma = Goal.sigma goal in + Ssrprinters.ppdebug (lazy + Pp.(str"interp-in: " ++ Printer.pr_glob_constr_env env glob)); + try + let sigma,term = Tacinterp.interp_open_constr ist env sigma (glob,None) in + Ssrprinters.ppdebug (lazy + Pp.(str"interp-out: " ++ Printer.pr_econstr_env env sigma term)); + tclUNIT (env,sigma,term) + with e -> + Ssrprinters.ppdebug (lazy + Pp.(str"interp-err: " ++ Printer.pr_glob_constr_env env glob)); + tclZERO e +end + +(* Commits the term to the monad *) +(* I think we should make the API safe by storing here the original evar map, + * so that one cannot commit it wrongly. + * We could also commit the term automatically, but this makes the code less + * modular, see the 2 functions below that would need to "uncommit" *) +let tclKeepOpenConstr (_env, sigma, t) = Unsafe.tclEVARS sigma <*> tclUNIT t + +(* The ssr heuristic : *) +(* Estimate a bound on the number of arguments of a raw constr. *) +(* This is not perfect, because the unifier may fail to *) +(* typecheck the partial application, so we use a minimum of 5. *) +(* Also, we don't handle delayed or iterated coercions to *) +(* FUNCLASS, which is probably just as well since these can *) +(* lead to infinite arities. *) +let guess_max_implicits ist glob = + Proofview.tclORELSE + (interp_glob ist (mkGApp glob (mkGHoles 6)) >>= fun (env,sigma,term) -> + let term_ty = Retyping.get_type_of env sigma term in + let ctx, _ = Reductionops.splay_prod env sigma term_ty in + tclUNIT (List.length ctx + 6)) + (fun _ -> tclUNIT 5) + +let pad_to_inductive ist glob = Goal.enter_one ~__LOC__ begin fun goal -> + interp_glob ist glob >>= fun (env, sigma, term) -> + let term_ty = Retyping.get_type_of env sigma term in + let ctx, i = Reductionops.splay_prod env sigma term_ty in + let rel_ctx = + List.map (fun (a,b) -> Context.Rel.Declaration.LocalAssum(a,b)) ctx in + if Ssrcommon.isAppInd (EConstr.push_rel_context rel_ctx env) sigma i + then tclUNIT (mkGApp glob (mkGHoles (List.length ctx))) + else Tacticals.New.tclZEROMSG Pp.(str"not an inductive") +end + +(* There are two ways of "applying" a view to term: *) +(* 1- using a view hint if the view is an instance of some *) +(* (reflection) inductive predicate. *) +(* 2- applying the view if it coerces to a function, adding *) +(* implicit arguments. *) +(* They require guessing the view hints and the number of *) +(* implicits, respectively, which we do by brute force. *) +(* Builds v p *) +let interp_view ist v p = + let is_specialize hd = + match DAst.get hd with Glob_term.GHole _ -> true | _ -> false in + (* We cast the pile of views p into a term p_id *) + tclINJ_CONSTR_IST ist p >>= fun (ist, p_id) -> + let p_id = DAst.make p_id in + match DAst.get v with + | Glob_term.GApp (hd, rargs) when is_specialize hd -> + Ssrprinters.ppdebug (lazy Pp.(str "specialize")); + interp_glob ist (mkGApp p_id rargs) >>= tclKeepOpenConstr + | _ -> + Ssrprinters.ppdebug (lazy Pp.(str "view")); + (* We find out how to build (v p) eventually using an adaptor *) + let adaptors = AdaptorDb.(get Forward) in + Proofview.tclORELSE + (pad_to_inductive ist v >>= fun vpad -> + Ssrcommon.tclFIRSTa (List.map + (fun a -> interp_glob ist (mkGApp a [vpad; p_id])) adaptors)) + (fun _ -> + guess_max_implicits ist v >>= fun n -> + Ssrcommon.tclFIRSTi (fun n -> + interp_glob ist (mkGApp v (mkGHoles n @ [p_id]))) n) + >>= tclKeepOpenConstr + +(* we store in the state (v top), then (v1 (v2 top))... *) +let pile_up_view (ist, v) = + let ist = Ssrcommon.option_assert_get ist (Pp.str"not a term") in + State.vsPUSH (fun p -> interp_view ist v p) + +let finalize_view s0 ?(simple_types=true) p = +Goal.enter_one ~__LOC__ begin fun g -> + let env = Goal.env g in + let sigma = Goal.sigma g in + let evars_of_p = Evd.evars_of_term (EConstr.to_constr sigma p) in + let filter x _ = Evar.Set.mem x evars_of_p in + let sigma = Typeclasses.resolve_typeclasses ~fail:false ~filter env sigma in + let p = Reductionops.nf_evar sigma p in + let get_body = function Evd.Evar_defined x -> x | _ -> assert false in + let evars_of_econstr sigma t = + Evd.evars_of_term (EConstr.to_constr sigma (EConstr.of_constr t)) in + let rigid_of s = + List.fold_left (fun l k -> + if Evd.is_defined sigma k then + let bo = get_body Evd.(evar_body (find sigma k)) in + k :: l @ Evar.Set.elements (evars_of_econstr sigma bo) + else l + ) [] s in + let und0 = (* Unassigned evars in the initial goal *) + let sigma0 = Tacmach.project s0 in + let g0info = Evd.find sigma0 (Tacmach.sig_it s0) in + let g0 = Evd.evars_of_filtered_evar_info g0info in + List.filter (fun k -> Evar.Set.mem k g0) + (List.map fst (Evar.Map.bindings (Evd.undefined_map sigma0))) in + let rigid = rigid_of und0 in + let n, p, to_prune, _ucst = pf_abs_evars2 s0 rigid (sigma, p) in + let p = if simple_types then pf_abs_cterm s0 n p else p in + Ssrprinters.ppdebug (lazy Pp.(str"view@finalized: " ++ + Printer.pr_econstr_env env sigma p)); + let sigma = List.fold_left Evd.remove sigma to_prune in + Unsafe.tclEVARS sigma <*> + tclUNIT p +end + +let pose_proof subject_name p = + Tactics.generalize [p] <*> + Option.cata + (fun id -> Ssrcommon.tclRENAME_HD_PROD (Name.Name id)) (tclUNIT()) + subject_name + <*> + Tactics.New.reduce_after_refine + +let rec apply_all_views ending vs s0 = + match vs with + | [] -> ending s0 + | v :: vs -> + Ssrprinters.ppdebug (lazy Pp.(str"piling...")); + is_tac_in_term v >>= function + | `Tac tac -> + Ssrprinters.ppdebug (lazy Pp.(str"..a tactic")); + ending s0 <*> Tacinterp.eval_tactic tac <*> + Ssrcommon.tacSIGMA >>= apply_all_views ending vs + | `Term v -> + Ssrprinters.ppdebug (lazy Pp.(str"..a term")); + pile_up_view v <*> apply_all_views ending vs s0 + +(* Entry points *********************************************************) + +let tclIPAT_VIEWS ~views:vs ~conclusion:tac = + let end_view_application s0 = + State.vsCONSUME (fun name t -> + finalize_view s0 t >>= pose_proof name <*> + tac ~to_clear:(Option.cata (fun x -> [x]) [] name)) in + tclINDEPENDENT begin + State.vsASSERT_EMPTY <*> + Ssrcommon.tacSIGMA >>= apply_all_views end_view_application vs <*> + State.vsASSERT_EMPTY + end + +let tclWITH_FWD_VIEWS ~simple_types ~subject ~views:vs ~conclusion:tac = + let ending_tac s0 = + State.vsCONSUME (fun _ t -> finalize_view s0 ~simple_types t >>= tac) in + tclINDEPENDENT begin + State.vsASSERT_EMPTY <*> + State.vsINIT subject <*> + Ssrcommon.tacSIGMA >>= apply_all_views ending_tac vs <*> + State.vsASSERT_EMPTY + end + +(* vim: set filetype=ocaml foldmethod=marker: *) |