1 (* Copyright (C) 2002, HELM Team.
3 * This file is part of HELM, an Hypertextual, Electronic
4 * Library of Mathematics, developed at the Computer Science
5 * Department, University of Bologna, Italy.
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22 * For details, see the HELM World-Wide-Web page,
23 * http://cs.unibo.it/helm/.
26 exception Bad_pattern of string Lazy.t
28 let new_meta_of_proof ~proof:(_, metasenv, _, _) =
29 CicMkImplicit.new_meta metasenv []
31 let subst_meta_in_proof proof meta term newmetasenv =
32 let uri,metasenv,bo,ty = proof in
33 (* empty context is ok for term since it wont be used by apply_subst *)
34 (* hack: since we do not know the context and the type of term, we
35 create a substitution with cc =[] and type = Implicit; they will be
36 in any case dropped by apply_subst, but it would be better to rewrite
37 the code. Cannot we just use apply_subst_metasenv, etc. ?? *)
38 let subst_in = CicMetaSubst.apply_subst [meta,([], term,Cic.Implicit None)] in
40 newmetasenv @ (List.filter (function (m,_,_) -> m <> meta) metasenv)
44 (function i,canonical_context,ty ->
45 let canonical_context' =
48 Some (n,Cic.Decl s) -> Some (n,Cic.Decl (subst_in s))
49 | Some (n,Cic.Def (s,None)) -> Some (n,Cic.Def (subst_in s,None))
51 | Some (n,Cic.Def (bo,Some ty)) ->
52 Some (n,Cic.Def (subst_in bo,Some (subst_in ty)))
55 i,canonical_context',(subst_in ty)
58 let bo' = subst_in bo in
59 (* Metavariables can appear also in the *statement* of the theorem
60 * since the parser does not reject as statements terms with
61 * metavariable therein *)
62 let ty' = subst_in ty in
63 let newproof = uri,metasenv'',bo',ty' in
64 (newproof, metasenv'')
66 (*CSC: commento vecchio *)
67 (* refine_meta_with_brand_new_metasenv meta term subst_in newmetasenv *)
68 (* This (heavy) function must be called when a tactic can instantiate old *)
69 (* metavariables (i.e. existential variables). It substitues the metasenv *)
70 (* of the proof with the result of removing [meta] from the domain of *)
71 (* [newmetasenv]. Then it replaces Cic.Meta [meta] with [term] everywhere *)
72 (* in the current proof. Finally it applies [apply_subst_replacing] to *)
74 (*CSC: A questo punto perche' passare un bo' gia' istantiato, se tanto poi *)
75 (*CSC: ci ripasso sopra apply_subst!!! *)
76 (*CSC: Attenzione! Ora questa funzione applica anche [subst_in] a *)
77 (*CSC: [newmetasenv]. *)
78 let subst_meta_and_metasenv_in_proof proof meta subst_in newmetasenv =
79 let (uri,_,bo,ty) = proof in
80 let bo' = subst_in bo in
81 (* Metavariables can appear also in the *statement* of the theorem
82 * since the parser does not reject as statements terms with
83 * metavariable therein *)
84 let ty' = subst_in ty in
87 (fun metasenv_entry i ->
88 match metasenv_entry with
89 (m,canonical_context,ty) when m <> meta ->
90 let canonical_context' =
94 | Some (i,Cic.Decl t) -> Some (i,Cic.Decl (subst_in t))
95 | Some (i,Cic.Def (t,None)) ->
96 Some (i,Cic.Def (subst_in t,None))
97 | Some (i,Cic.Def (bo,Some ty)) ->
98 Some (i,Cic.Def (subst_in bo,Some (subst_in ty)))
101 (m,canonical_context',subst_in ty)::i
105 let newproof = uri,metasenv',bo',ty' in
106 (newproof, metasenv')
108 let compare_metasenvs ~oldmetasenv ~newmetasenv =
109 List.map (function (i,_,_) -> i)
112 not (List.exists (fun (j,_,_) -> i=j) oldmetasenv)) newmetasenv)
115 (** finds the _pointers_ to subterms that are alpha-equivalent to wanted in t *)
116 let find_subterms ~subst ~metasenv ~ugraph ~wanted ~context t =
117 let rec find subst metasenv ugraph context w t =
119 let subst,metasenv,ugraph =
120 CicUnification.fo_unif_subst subst context metasenv w t ugraph
122 subst,metasenv,ugraph,[context,t]
124 CicUnification.UnificationFailure _
125 | CicUnification.Uncertain _ ->
128 | Cic.Rel _ -> subst,metasenv,ugraph,[]
129 | Cic.Meta (_, ctx) ->
131 fun (subst,metasenv,ugraph,acc) e ->
133 | None -> subst,metasenv,ugraph,acc
135 let subst,metasenv,ugraph,res =
136 find subst metasenv ugraph context w t
138 subst,metasenv,ugraph, res @ acc
139 ) (subst,metasenv,ugraph,[]) ctx
140 | Cic.Lambda (name, t1, t2)
141 | Cic.Prod (name, t1, t2) ->
142 let subst,metasenv,ugraph,rest1 =
143 find subst metasenv ugraph context w t1 in
144 let subst,metasenv,ugraph,rest2 =
145 find subst metasenv ugraph (Some (name, Cic.Decl t1)::context)
146 (CicSubstitution.lift 1 w) t2
148 subst,metasenv,ugraph,rest1 @ rest2
149 | Cic.LetIn (name, t1, t2) ->
150 let subst,metasenv,ugraph,rest1 =
151 find subst metasenv ugraph context w t1 in
152 let subst,metasenv,ugraph,rest2 =
153 find subst metasenv ugraph (Some (name, Cic.Def (t1,None))::context)
154 (CicSubstitution.lift 1 w) t2
156 subst,metasenv,ugraph,rest1 @ rest2
159 (fun (subst,metasenv,ugraph,acc) t ->
160 let subst,metasenv,ugraph,res =
161 find subst metasenv ugraph context w t
163 subst,metasenv,ugraph,res @ acc)
164 (subst,metasenv,ugraph,[]) l
165 | Cic.Cast (t, ty) ->
166 let subst,metasenv,ugraph,rest =
167 find subst metasenv ugraph context w t in
168 let subst,metasenv,ugraph,resty =
169 find subst metasenv ugraph context w ty
171 subst,metasenv,ugraph,rest @ resty
172 | Cic.Implicit _ -> assert false
173 | Cic.Const (_, esubst)
174 | Cic.Var (_, esubst)
175 | Cic.MutInd (_, _, esubst)
176 | Cic.MutConstruct (_, _, _, esubst) ->
178 (fun (subst,metasenv,ugraph,acc) (_, t) ->
179 let subst,metasenv,ugraph,res =
180 find subst metasenv ugraph context w t
182 subst,metasenv,ugraph,res @ acc)
183 (subst,metasenv,ugraph,[]) esubst
184 | Cic.MutCase (_, _, outty, indterm, patterns) ->
185 let subst,metasenv,ugraph,resoutty =
186 find subst metasenv ugraph context w outty in
187 let subst,metasenv,ugraph,resindterm =
188 find subst metasenv ugraph context w indterm in
189 let subst,metasenv,ugraph,respatterns =
191 (fun (subst,metasenv,ugraph,acc) p ->
192 let subst,metaseng,ugraph,res =
193 find subst metasenv ugraph context w p
195 subst,metasenv,ugraph,res @ acc
196 ) (subst,metasenv,ugraph,[]) patterns
198 subst,metasenv,ugraph,resoutty @ resindterm @ respatterns
199 | Cic.Fix (_, funl) ->
201 List.map (fun (n,_,ty,_) -> Some (Cic.Name n,(Cic.Decl ty))) funl
204 fun (subst,metasenv,ugraph,acc) (_, _, ty, bo) ->
205 let subst,metasenv,ugraph,resty =
206 find subst metasenv ugraph context w ty in
207 let subst,metasenv,ugraph,resbo =
208 find subst metasenv ugraph (tys @ context) w bo
210 subst,metasenv,ugraph, resty @ resbo @ acc
211 ) (subst,metasenv,ugraph,[]) funl
212 | Cic.CoFix (_, funl) ->
214 List.map (fun (n,ty,_) -> Some (Cic.Name n,(Cic.Decl ty))) funl
217 fun (subst,metasenv,ugraph,acc) (_, ty, bo) ->
218 let subst,metasenv,ugraph,resty =
219 find subst metasenv ugraph context w ty in
220 let subst,metasenv,ugraph,resbo =
221 find subst metasenv ugraph (tys @ context) w bo
223 subst,metasenv,ugraph, resty @ resbo @ acc
224 ) (subst,metasenv,ugraph,[]) funl
226 find subst metasenv ugraph context wanted t
228 let select_in_term ~metasenv ~context ~ugraph ~term ~pattern:(wanted,where) =
229 let add_ctx context name entry = (Some (name, entry)) :: context in
230 let map2 error_msg f l1 l2 =
234 | Invalid_argument _ -> raise (Bad_pattern (lazy error_msg))
236 let rec aux context where term =
237 match (where, term) with
238 | Cic.Implicit (Some `Hole), t -> [context,t]
239 | Cic.Implicit (Some `Type), t -> []
240 | Cic.Implicit None,_ -> []
241 | Cic.Meta (_, ctxt1), Cic.Meta (_, ctxt2) ->
243 (map2 "wrong number of argument in explicit substitution"
246 Some t1, Some t2 -> aux context t1 t2
249 | Cic.Cast (te1, ty1), Cic.Cast (te2, ty2) ->
250 aux context te1 te2 @ aux context ty1 ty2
251 | Cic.Prod (Cic.Anonymous, s1, t1), Cic.Prod (name, s2, t2)
252 | Cic.Lambda (Cic.Anonymous, s1, t1), Cic.Lambda (name, s2, t2) ->
253 aux context s1 s2 @ aux (add_ctx context name (Cic.Decl s2)) t1 t2
254 | Cic.Prod (Cic.Name n1, s1, t1),
255 Cic.Prod ((Cic.Name n2) as name , s2, t2)
256 | Cic.Lambda (Cic.Name n1, s1, t1),
257 Cic.Lambda ((Cic.Name n2) as name, s2, t2) when n1 = n2->
258 aux context s1 s2 @ aux (add_ctx context name (Cic.Decl s2)) t1 t2
259 | Cic.Prod (name1, s1, t1), Cic.Prod (name2, s2, t2)
260 | Cic.Lambda (name1, s1, t1), Cic.Lambda (name2, s2, t2) -> []
261 | Cic.LetIn (Cic.Anonymous, s1, t1), Cic.LetIn (name, s2, t2) ->
262 aux context s1 s2 @ aux (add_ctx context name (Cic.Def (s2,None))) t1 t2
263 | Cic.LetIn (Cic.Name n1, s1, t1),
264 Cic.LetIn ((Cic.Name n2) as name, s2, t2) when n1 = n2->
265 aux context s1 s2 @ aux (add_ctx context name (Cic.Def (s2,None))) t1 t2
266 | Cic.LetIn (name1, s1, t1), Cic.LetIn (name2, s2, t2) -> []
267 | Cic.Appl terms1, Cic.Appl terms2 -> auxs context terms1 terms2
268 | Cic.Var (_, subst1), Cic.Var (_, subst2)
269 | Cic.Const (_, subst1), Cic.Const (_, subst2)
270 | Cic.MutInd (_, _, subst1), Cic.MutInd (_, _, subst2)
271 | Cic.MutConstruct (_, _, _, subst1), Cic.MutConstruct (_, _, _, subst2) ->
272 auxs context (List.map snd subst1) (List.map snd subst2)
273 | Cic.MutCase (_, _, out1, t1, pat1), Cic.MutCase (_ , _, out2, t2, pat2) ->
274 aux context out1 out2 @ aux context t1 t2 @ auxs context pat1 pat2
275 | Cic.Fix (_, funs1), Cic.Fix (_, funs2) ->
277 List.map (fun (n,_,ty,_) -> Some (Cic.Name n,(Cic.Decl ty))) funs2
280 (map2 "wrong number of mutually recursive functions"
281 (fun (_, _, ty1, bo1) (_, _, ty2, bo2) ->
282 aux context ty1 ty2 @ aux (tys @ context) bo1 bo2)
284 | Cic.CoFix (_, funs1), Cic.CoFix (_, funs2) ->
286 List.map (fun (n,ty,_) -> Some (Cic.Name n,(Cic.Decl ty))) funs2
289 (map2 "wrong number of mutually co-recursive functions"
290 (fun (_, ty1, bo1) (_, ty2, bo2) ->
291 aux context ty1 ty2 @ aux (tys @ context) bo1 bo2)
295 (lazy (Printf.sprintf "Pattern %s versus term %s"
298 and auxs context terms1 terms2 = (* as aux for list of terms *)
299 List.concat (map2 "wrong number of arguments in application"
300 (fun t1 t2 -> aux context t1 t2) terms1 terms2)
305 | Some where -> aux context where term
308 None -> [],metasenv,ugraph,roots
310 let rec find_in_roots =
312 [] -> [],metasenv,ugraph,[]
313 | (context',where)::tl ->
314 let subst,metasenv,ugraph,tl' = find_in_roots tl in
315 let subst,metasenv,ugraph,found =
316 let wanted, metasenv, ugraph = wanted context' metasenv ugraph in
317 find_subterms ~subst ~metasenv ~ugraph ~wanted ~context:context'
320 subst,metasenv,ugraph,found @ tl'
324 (** create a pattern from a term and a list of subterms.
325 * the pattern is granted to have a ? for every subterm that has no selected
327 * @param equality equality function used while walking the term. Defaults to
328 * physical equality (==) *)
329 let pattern_of ?(equality=(==)) ~term terms =
330 let (===) x y = equality x y in
331 let not_found = false, Cic.Implicit None in
334 | t when List.exists (fun t' -> t === t') terms ->
335 true,Cic.Implicit (Some `Hole)
336 | Cic.Var (uri, subst) ->
337 let b,subst = aux_subst subst in
339 true,Cic.Var (uri, subst)
342 | Cic.Meta (i, ctxt) ->
348 | Some t -> let bt,t = aux t in b||bt ,Some t::ctxt
352 true,Cic.Meta (i, ctxt)
355 | Cic.Cast (te, ty) ->
356 let b1,te = aux te in
357 let b2,ty = aux ty in
358 if b1||b2 then true,Cic.Cast (te, ty)
361 | Cic.Prod (name, s, t) ->
365 true, Cic.Prod (name, s, t)
368 | Cic.Lambda (name, s, t) ->
372 true, Cic.Lambda (name, s, t)
375 | Cic.LetIn (name, s, t) ->
379 true, Cic.LetIn (name, s, t)
394 | Cic.Const (uri, subst) ->
395 let b,subst = aux_subst subst in
397 true, Cic.Const (uri, subst)
400 | Cic.MutInd (uri, tyno, subst) ->
401 let b,subst = aux_subst subst in
403 true, Cic.MutInd (uri, tyno, subst)
406 | Cic.MutConstruct (uri, tyno, consno, subst) ->
407 let b,subst = aux_subst subst in
409 true, Cic.MutConstruct (uri, tyno, consno, subst)
412 | Cic.MutCase (uri, tyno, outty, t, pat) ->
413 let b1,outty = aux outty in
422 if b1 || b2 || b3 then
423 true, Cic.MutCase (uri, tyno, outty, t, pat)
426 | Cic.Fix (funno, funs) ->
429 (fun (name, i, ty, bo) (b,funs) ->
430 let b1,ty = aux ty in
431 let b2,bo = aux bo in
432 b||b1||b2, (name, i, ty, bo)::funs) funs (false,[])
435 true, Cic.Fix (funno, funs)
438 | Cic.CoFix (funno, funs) ->
441 (fun (name, ty, bo) (b,funs) ->
442 let b1,ty = aux ty in
443 let b2,bo = aux bo in
444 b||b1||b2, (name, ty, bo)::funs) funs (false,[])
447 true, Cic.CoFix (funno, funs)
452 | Cic.Implicit _ -> not_found
453 and aux_subst subst =
455 (fun (uri, t) (b,subst) ->
457 b||b1,(uri, t)::subst) subst (false,[])
461 exception Fail of string Lazy.t
463 (** select metasenv conjecture pattern
464 * select all subterms of [conjecture] matching [pattern].
465 * It returns the set of matched terms (that can be compared using physical
466 * equality to the subterms of [conjecture]) together with their contexts.
467 * The representation of the set mimics the ProofEngineTypes.pattern type:
468 * a list of hypothesis (names of) together with the list of its matched
469 * subterms (and their contexts) + the list of matched subterms of the
470 * with their context conclusion. Note: in the result the list of hypothesis
471 * has an entry for each entry in the context and in the same order.
472 * Of course the list of terms (with their context) associated to the
473 * hypothesis name may be empty.
477 let select ~metasenv ~ugraph ~conjecture:(_,context,ty)
478 ~(pattern: (Cic.term, Cic.lazy_term) ProofEngineTypes.pattern)
480 let what, hyp_patterns, goal_pattern = pattern in
481 let find_pattern_for name =
482 try Some (snd (List.find (fun (n, pat) -> Cic.Name n = name) hyp_patterns))
483 with Not_found -> None in
484 let subst,metasenv,ugraph,ty_terms =
485 select_in_term ~metasenv ~context ~ugraph ~term:ty
486 ~pattern:(what,goal_pattern) in
487 let subst,metasenv,ugraph,context_terms =
488 let subst,metasenv,ugraph,res,_ =
490 (fun entry (subst,metasenv,ugraph,res,context) ->
492 None -> subst,metasenv,ugraph,(None::res),(None::context)
493 | Some (name,Cic.Decl term) ->
494 (match find_pattern_for name with
496 subst,metasenv,ugraph,((Some (`Decl []))::res),(entry::context)
498 let subst,metasenv,ugraph,terms =
499 select_in_term ~metasenv ~context ~ugraph ~term
500 ~pattern:(what, Some pat)
502 subst,metasenv,ugraph,((Some (`Decl terms))::res),
504 | Some (name,Cic.Def (bo, ty)) ->
505 (match find_pattern_for name with
507 let selected_ty=match ty with None -> None | Some _ -> Some [] in
508 subst,metasenv,ugraph,((Some (`Def ([],selected_ty)))::res),
511 let subst,metasenv,ugraph,terms_bo =
512 select_in_term ~metasenv ~context ~ugraph ~term:bo
513 ~pattern:(what, Some pat) in
514 let subst,metasenv,ugraph,terms_ty =
516 None -> subst,metasenv,ugraph,None
518 let subst,metasenv,ugraph,res =
519 select_in_term ~metasenv ~context ~ugraph ~term:ty
520 ~pattern:(what, Some pat)
522 subst,metasenv,ugraph,Some res
524 subst,metasenv,ugraph,((Some (`Def (terms_bo,terms_ty)))::res),
526 ) context (subst,metasenv,ugraph,[],[]))
528 subst,metasenv,ugraph,res
530 subst,metasenv,ugraph,context_terms, ty_terms
532 (** locate_in_term equality what where context
533 * [what] must match a subterm of [where] according to [equality]
534 * It returns the matched terms together with their contexts in [where]
535 * [equality] defaults to physical equality
536 * [context] must be the context of [where]
538 let locate_in_term ?(equality=(fun _ -> (==))) what ~where context =
539 let add_ctx context name entry =
540 (Some (name, entry)) :: context in
541 let rec aux context where =
542 if equality context what where then [context,where]
552 | Cic.MutConstruct _ -> []
553 | Cic.Cast (te, ty) -> aux context te @ aux context ty
554 | Cic.Prod (name, s, t)
555 | Cic.Lambda (name, s, t) ->
556 aux context s @ aux (add_ctx context name (Cic.Decl s)) t
557 | Cic.LetIn (name, s, t) ->
558 aux context s @ aux (add_ctx context name (Cic.Def (s,None))) t
559 | Cic.Appl tl -> auxs context tl
560 | Cic.MutCase (_, _, out, t, pat) ->
561 aux context out @ aux context t @ auxs context pat
562 | Cic.Fix (_, funs) ->
564 List.map (fun (n,_,ty,_) -> Some (Cic.Name n,(Cic.Decl ty))) funs
568 (fun (_, _, ty, bo) ->
569 aux context ty @ aux (tys @ context) bo)
571 | Cic.CoFix (_, funs) ->
573 List.map (fun (n,ty,_) -> Some (Cic.Name n,(Cic.Decl ty))) funs
578 aux context ty @ aux (tys @ context) bo)
580 and auxs context tl = (* as aux for list of terms *)
581 List.concat (List.map (fun t -> aux context t) tl)
585 (** locate_in_conjecture equality what where context
586 * [what] must match a subterm of [where] according to [equality]
587 * It returns the matched terms together with their contexts in [where]
588 * [equality] defaults to physical equality
589 * [context] must be the context of [where]
591 let locate_in_conjecture ?(equality=fun _ -> (==)) what (_,context,ty) =
594 (fun entry (context,res) ->
596 None -> entry::context, res
597 | Some (_, Cic.Decl ty) ->
598 let res = res @ locate_in_term what ~where:ty context in
599 let context' = entry::context in
601 | Some (_, Cic.Def (bo,ty)) ->
602 let res = res @ locate_in_term what ~where:bo context in
607 res @ locate_in_term what ~where:ty context in
608 let context' = entry::context in
612 res @ locate_in_term what ~where:ty context
614 (* saturate_term newmeta metasenv context ty goal_arity *)
615 (* Given a type [ty] (a backbone), it returns its suffix of length *)
616 (* [goal_arity] head and a new metasenv in which there is new a META for each *)
617 (* hypothesis, a list of arguments for the new applications and the index of *)
618 (* the last new META introduced. The nth argument in the list of arguments is *)
619 (* just the nth new META. *)
620 let saturate_term newmeta metasenv context ty goal_arity =
621 let module C = Cic in
622 let module S = CicSubstitution in
623 assert (goal_arity >= 0);
624 let rec aux newmeta ty =
626 C.Cast (he,_) -> aux newmeta he
627 (* CSC: patch to generate ?1 : ?2 : Type in place of ?1 : Type to simulate ?1 :< Type
628 (* If the expected type is a Type, then also Set is OK ==>
629 * we accept any term of type Type *)
630 (*CSC: BUG HERE: in this way it is possible for the term of
631 * type Type to be different from a Sort!!! *)
632 | C.Prod (name,(C.Sort (C.Type _) as s),t) ->
633 (* TASSI: ask CSC if BUG HERE refers to the C.Cast or C.Propd case *)
635 CicMkImplicit.identity_relocation_list_for_metavariable context
637 let newargument = C.Meta (newmeta+1,irl) in
638 let (res,newmetasenv,arguments,lastmeta) =
639 aux (newmeta + 2) (S.subst newargument t)
642 (newmeta,[],s)::(newmeta+1,context,C.Meta (newmeta,[]))::newmetasenv,
643 newargument::arguments,lastmeta
645 | C.Prod (name,s,t) ->
647 CicMkImplicit.identity_relocation_list_for_metavariable context
649 let newargument = C.Meta (newmeta,irl) in
650 let res,newmetasenv,arguments,lastmeta,prod_no =
651 aux (newmeta + 1) (S.subst newargument t)
653 if prod_no + 1 = goal_arity then
654 let head = CicReduction.normalize ~delta:false context ty in
655 head,[],[],lastmeta,goal_arity + 1
657 (** NORMALIZE RATIONALE
658 * we normalize the target only NOW since we may be in this case:
659 * A1 -> A2 -> T where T = (\lambda x.A3 -> P) k
660 * and we want a mesasenv with ?1:A1 and ?2:A2 and not
661 * ?1, ?2, ?3 (that is the one we whould get if we start from the
662 * beta-normalized A1 -> A2 -> A3 -> P **)
663 let s' = CicReduction.normalize ~delta:false context s in
664 res,(newmeta,context,s')::newmetasenv,newargument::arguments,
667 let head = CicReduction.normalize ~delta:false context t in
668 match CicReduction.whd context head with
669 C.Prod _ as head' -> aux newmeta head'
670 | _ -> head,[],[],newmeta,0
672 (* WARNING: here we are using the invariant that above the most *)
673 (* recente new_meta() there are no used metas. *)
674 let res,newmetasenv,arguments,lastmeta,_ = aux newmeta ty in
675 res,metasenv @ newmetasenv,arguments,lastmeta
677 let lookup_type metasenv context hyp =
678 let rec aux p = function
679 | Some (Cic.Name name, Cic.Decl t) :: _ when name = hyp -> p, t
680 | Some (Cic.Name name, Cic.Def (_, Some t)) :: _ when name = hyp -> p, t
681 | Some (Cic.Name name, Cic.Def (u, _)) :: tail when name = hyp ->
682 p, fst (CicTypeChecker.type_of_aux' metasenv tail u CicUniv.empty_ugraph)
683 | _ :: tail -> aux (succ p) tail
684 | [] -> raise (ProofEngineTypes.Fail (lazy "lookup_type: not premise in the current goal"))