2 ||M|| This file is part of HELM, an Hypertextual, Electronic
3 ||A|| Library of Mathematics, developed at the Computer Science
4 ||T|| Department, University of Bologna, Italy.
6 ||T|| HELM is free software; you can redistribute it and/or
7 ||A|| modify it under the terms of the GNU General Public License
8 \ / version 2 or (at your option) any later version.
9 \ / This software is distributed as is, NO WARRANTY.
10 V_______________________________________________________________ *)
12 (* $Id: nCic.ml 9058 2008-10-13 17:42:30Z tassi $ *)
14 exception Error of string lazy_t
15 let fail msg = raise (Error msg)
17 type lowtac_status = {
19 lstatus : LexiconEngine.status
22 type lowtactic = lowtac_status -> int -> lowtac_status
25 gstatus : Continuationals.Stack.t;
26 istatus : lowtac_status;
29 type tactic = tac_status -> tac_status
31 type tactic_term = CicNotationPt.term Disambiguate.disambiguator_input
32 type tactic_pattern = GrafiteAst.npattern Disambiguate.disambiguator_input
34 let pp_tac_status status =
35 prerr_endline (NCicPp.ppobj status.istatus.pstatus)
38 let pp_lowtac_status status =
39 prerr_endline "--------------------------------------------";
40 prerr_endline (NCicPp.ppobj status.pstatus)
43 type cic_term = NCic.conjecture (* name, context, term *)
44 let ctx_of (_,c,_) = c ;;
46 let relocate status destination (name,source,t as orig) =
47 if source == destination then status, orig else
48 let u, d, metasenv, subst, o = status.pstatus in
49 let rec lcp ctx j i = function
50 | (n1, NCic.Decl t1 as e)::cl1, (n2, NCic.Decl t2)::cl2 ->
52 NCicReduction.are_convertible ctx ~subst ~metasenv t1 t2 then
53 NCic.Rel i :: lcp (e::ctx)(j-1) (i-1) (cl1,cl2)
55 HExtlib.mk_list (NCic.Appl
56 [NCic.Sort NCic.Prop; NCic.Sort NCic.Prop]) j
57 | (n1, NCic.Def (b1,t1) as e)::cl1, (n2, NCic.Def (b2,t2))::cl2 ->
59 NCicReduction.are_convertible ctx ~subst ~metasenv t1 t2 &&
60 NCicReduction.are_convertible ctx ~subst ~metasenv b1 b2 then
61 NCic.Rel i :: lcp (e::ctx)(j-1) (i-1) (cl1,cl2)
63 HExtlib.mk_list (NCic.Appl
64 [NCic.Sort NCic.Prop; NCic.Sort NCic.Prop]) j
65 | (n1, NCic.Def (b1,t1) as e)::cl1, (n2, NCic.Decl t2)::cl2 ->
67 NCicReduction.are_convertible ctx ~subst ~metasenv t1 t2 then
68 NCic.Rel i :: lcp (e::ctx)(j-1) (i-1) (cl1,cl2)
70 HExtlib.mk_list (NCic.Appl
71 [NCic.Sort NCic.Prop; NCic.Sort NCic.Prop]) j
72 | (n1, NCic.Decl _)::cl1, (n2, NCic.Def _)::cl2 -> assert false
74 HExtlib.mk_list (NCic.Appl
75 [NCic.Sort NCic.Prop; NCic.Sort NCic.Prop]) j
79 lcp [] (List.length destination) (List.length source)
80 (List.rev destination, List.rev source)
82 let lc = (0,NCic.Ctx (List.rev lc)) in
83 let db = NCicUnifHint.db () in (* XXX fixme *)
84 let (metasenv, subst), t =
86 ~unify:(fun m s c t1 t2 ->
87 try Some (NCicUnification.unify db m s c t1 t2)
89 | NCicUnification.UnificationFailure _
90 | NCicUnification.Uncertain _ -> None)
91 metasenv subst source 0 lc t
93 let status = { status with pstatus = u, d, metasenv, subst, o } in
94 status, (name, destination, t)
97 let term_of_cic_term s t c =
98 let s, (_,_,t) = relocate s c t in
102 let ppterm status t =
103 let uri,height,metasenv,subst,obj = status.pstatus in
104 let _,context,t = t in
105 NCicPp.ppterm ~metasenv ~subst ~context t
108 let disambiguate status t ty context =
111 | None -> status, None
113 let status, (_,_,x) = relocate status context ty in status, Some x
115 let uri,height,metasenv,subst,obj = status.pstatus in
116 let metasenv, subst, lexicon_status, t =
117 GrafiteDisambiguate.disambiguate_nterm expty
118 status.lstatus context metasenv subst t
120 let new_pstatus = uri,height,metasenv,subst,obj in
121 { lstatus = lexicon_status; pstatus = new_pstatus }, (None, context, t)
124 let typeof status ctx t =
125 let status, (_,_,t) = relocate status ctx t in
126 let _,_,metasenv,subst,_ = status.pstatus in
127 let ty = NCicTypeChecker.typeof ~subst ~metasenv ctx t in
128 status, (None, ctx, ty)
131 let whd status ?delta ctx t =
132 let status, (name,_,t) = relocate status ctx t in
133 let _,_,_,subst,_ = status.pstatus in
134 let t = NCicReduction.whd ~subst ?delta ctx t in
135 status, (name, ctx, t)
138 let normalize status ?delta ctx t =
139 let status, (name,_,t) = relocate status ctx t in
140 let _,_,_,subst,_ = status.pstatus in
141 let t = NCicTacReduction.normalize ~subst ?delta ctx t in
142 status, (name, ctx, t)
145 let unify status ctx a b =
146 let status, (_,_,a) = relocate status ctx a in
147 let status, (_,_,b) = relocate status ctx b in
148 let n,h,metasenv,subst,o = status.pstatus in
149 let metasenv, subst =
150 NCicUnification.unify (NCicUnifHint.db ()) metasenv subst ctx a b
152 { status with pstatus = n,h,metasenv,subst,o }
155 let refine status ctx term expty =
156 let status, (nt,_,term) = relocate status ctx term in
157 let status, ne, expty =
158 match expty with None -> status, None, None
160 let status, (n,_, e) = relocate status ctx e in status, n, Some e
162 let name,height,metasenv,subst,obj = status.pstatus in
163 let db = NCicUnifHint.db () in (* XXX fixme *)
164 let coercion_db = NCicCoercion.db () in
165 let look_for_coercion = NCicCoercion.look_for_coercion coercion_db in
166 let metasenv, subst, t, ty =
167 NCicRefiner.typeof db ~look_for_coercion metasenv subst ctx term expty
169 { status with pstatus = name,height,metasenv,subst,obj },
170 (nt,ctx,t), (ne,ctx,ty)
173 let get_goalty (status : lowtac_status) (g : int) =
174 let _,_,metasenv,_,_ = status.pstatus in
175 List.assoc g metasenv
178 let instantiate status i t =
179 let (gname, context, _ as gty) = get_goalty status i in
180 let status, (_,_,t), (_,_,ty) =
181 refine status (ctx_of gty) t (Some gty)
184 let name,height,metasenv,subst,obj = status.pstatus in
185 let metasenv = List.filter (fun j,_ -> j <> i) metasenv in
186 let subst = (i, (gname, context, t, ty)) :: subst in
187 { status with pstatus = (name,height,metasenv,subst,obj) }
190 let mk_meta status ?name ctx bo_or_ty =
193 let status, (_,_,ty) = relocate status ctx ty in
194 let n,h,metasenv,subst,o = status.pstatus in
195 let metasenv, _, instance, _ =
196 NCicMetaSubst.mk_meta ?name metasenv ctx (`WithType ty)
198 let status = { status with pstatus = n,h,metasenv,subst,o } in
199 status, (None,ctx,instance)
201 let status, (_,_,bo_ as bo) = relocate status ctx bo in
202 let status, (_,_,ty) = typeof status ctx bo in
203 let n,h,metasenv,subst,o = status.pstatus in
204 let metasenv, metano, instance, _ =
205 NCicMetaSubst.mk_meta ?name metasenv ctx (`WithType ty) in
206 let metasenv = List.filter (fun j,_ -> j <> metano) metasenv in
207 let subst = (metano, (name, ctx, bo_, ty)) :: subst in
208 let status = { status with pstatus = n,h,metasenv,subst,o } in
209 status, (None,ctx,instance)
212 let mk_in_scope status t =
213 mk_meta status ~name:NCicMetaSubst.in_scope_tag (ctx_of t) (`Def t)
216 let mk_out_scope n status t =
217 mk_meta status ~name:(NCicMetaSubst.out_scope_tag n) (ctx_of t) (`Def t)
220 (* the following unification problem will be driven by
221 * select s ~found:mk_in_scope ~postprocess:(mk_out_scope argsno) t pattern
225 * where argsn = length args and the pattern matches t
227 * found is called on every selected term to map them
228 * postprocess is called on the entire term after selection
231 low_status ~found ~postprocess (name,context,term) (wanted,path)
233 let is_found status ctx t wanted =
234 (* we could lift wanted step-by-step *)
235 try true, unify status ctx (None, ctx, t) wanted
237 | NCicUnification.UnificationFailure _
238 | NCicUnification.Uncertain _ -> false, status
240 let match_term status ctx (wanted : cic_term) t =
241 let rec aux ctx (status,already_found) t =
242 let b, status = is_found status ctx t wanted in
244 let status , (_,_,t) = found status (None, ctx, t) in
247 let _,_,_,subst,_ = status.pstatus in
249 | NCic.Meta (i,lc) when List.mem_assoc i subst ->
250 let _,_,t,_ = NCicUtils.lookup_subst i subst in
251 aux ctx (status,already_found) t
252 | NCic.Meta _ -> (status,already_found),t
254 NCicUntrusted.map_term_fold_a (fun e c -> e::c) ctx aux
255 (status,already_found) t
257 aux ctx (status,false) t
259 let _,_,_,subst,_ = low_status.pstatus in
260 let rec select status ctx pat cic =
262 | _, NCic.Meta (i,lc) when List.mem_assoc i subst ->
264 let _,_,t,_ = NCicUtils.lookup_subst i subst in
265 NCicSubstitution.subst_meta lc t
267 select status ctx pat cic
268 | NCic.LetIn (_,t1,s1,b1), NCic.LetIn (n,t2,s2,b2) ->
269 let status, t = select status ctx t1 t2 in
270 let status, s = select status ctx s1 s2 in
271 let ctx = (n, NCic.Def (s2,t2)) :: ctx in
272 let status, b = select status ctx b1 b2 in
273 status, NCic.LetIn (n,t,s,b)
274 | NCic.Lambda (_,s1,t1), NCic.Lambda (n,s2,t2) ->
275 let status, s = select status ctx s1 s2 in
276 let ctx = (n, NCic.Decl s2) :: ctx in
277 let status, t = select status ctx t1 t2 in
278 status, NCic.Lambda (n,s,t)
279 | NCic.Prod (_,s1,t1), NCic.Prod (n,s2,t2) ->
280 let status, s = select status ctx s1 s2 in
281 let ctx = (n, NCic.Decl s2) :: ctx in
282 let status, t = select status ctx t1 t2 in
283 status, NCic.Prod (n,s,t)
284 | NCic.Appl l1, NCic.Appl l2 ->
287 (fun (status,l) x y ->
288 let status, x = select status ctx x y in
292 status, NCic.Appl (List.rev l)
293 | NCic.Match (_,ot1,t1,pl1), NCic.Match (u,ot2,t2,pl2) ->
294 let status, t = select status ctx t1 t2 in
295 let status, ot = select status ctx ot1 ot2 in
298 (fun (status,l) x y ->
299 let status, x = select status ctx x y in
303 status, NCic.Match (u,ot,t,List.rev pl)
304 | NCic.Implicit `Hole, t ->
307 let status', wanted = disambiguate status wanted None ctx in
308 let (status',found), t' = match_term status' ctx wanted t in
309 if found then status',t' else status,t
311 let (status,_),t = match_term status ctx (None,ctx,t) t in
313 | NCic.Implicit _, t -> status, t
315 fail (lazy ("malformed pattern: " ^ NCicPp.ppterm ~metasenv:[]
316 ~context:[] ~subst:[] pat ^ " against " ^
317 NCicPp.ppterm ~metasenv:[] ~subst:[] ~context:[] t))
319 let status, term = select low_status context path term in
320 let term = (name, context, term) in
321 postprocess status term
324 let analyse_indty status ty =
325 let status, reduct = whd status (ctx_of ty) ty in
328 | _,_,NCic.Const ref -> ref, []
329 | _,_,NCic.Appl (NCic.Const ref :: args) -> ref, args
330 | _,_,_ -> fail (lazy ("not an inductive type")) in
331 let _,lno,tl,_,i = NCicEnvironment.get_checked_indtys ref in
332 let _,_,_,cl = List.nth tl i in
333 let consno = List.length cl in
334 let left, right = HExtlib.split_nth lno args in
335 status, (ref, consno, left, right)
338 let mk_cic_term c t = None,c,t ;;
340 let apply_subst status ctx t =
341 let status, (name,_,t) = relocate status ctx t in
342 let _,_,_,subst,_ = status.pstatus in
343 status, (name, ctx, NCicUntrusted.apply_subst subst ctx t)