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_______________________________________________________________ *)
14 exception RefineFailure of (Stdpp.location * string) Lazy.t;;
15 exception Uncertain of (Stdpp.location * string) Lazy.t;;
16 exception AssertFailure of string Lazy.t;;
19 module Ref = NReference
21 let wrap_exc msg = function
22 | NCicUnification.Uncertain _ -> Uncertain msg
23 | NCicUnification.UnificationFailure _ -> RefineFailure msg
24 | NCicTypeChecker.TypeCheckerFailure _ -> RefineFailure msg
28 let exp_implicit metasenv context expty =
29 let foo x = match expty with Some t -> `WithType t | None -> x in
31 | `Closed -> NCicMetaSubst.mk_meta metasenv [] (foo `Type)
32 | `Type -> NCicMetaSubst.mk_meta metasenv context (foo `Type)
33 | `Term -> NCicMetaSubst.mk_meta metasenv context (foo `Term)
37 let force_to_sort metasenv subst context t =
38 match NCicReduction.whd ~subst context t with
39 | C.Meta (_,(_,(C.Irl 0 | C.Ctx []))) as t ->
41 | C.Meta (i,(_,lc)) as t ->
42 let len = match lc with C.Irl len->len | C.Ctx l->List.length l in
43 prerr_endline "RESTRICT";
44 let metasenv, subst, _ =
45 NCicMetaSubst.restrict metasenv subst i (HExtlib.list_seq 1 len)
48 | C.Sort _ -> metasenv, subst, t
53 localise metasenv subst context orig_s orig_t (name,s) t (t1, t2)
55 let metasenv, subst, t1 = force_to_sort metasenv subst context t1 in
56 let metasenv, subst, t2 =
57 force_to_sort metasenv subst ((name,C.Decl s)::context) t2 in
58 prerr_endline ("S1:"^NCicPp.ppterm ~metasenv ~subst ~context t1);
59 prerr_endline ("S2:"^NCicPp.ppterm ~metasenv ~subst ~context:((name,C.Decl s)::context) t2);
61 | C.Sort _, C.Sort C.Prop -> metasenv, subst, t2
62 | C.Sort (C.Type u1), C.Sort (C.Type u2) ->
63 metasenv, subst, C.Sort (C.Type (u1@u2))
64 | C.Sort C.Prop,C.Sort (C.Type _) -> metasenv, subst, t2
67 | C.Sort _, C.Meta _ -> metasenv, subst, t2
68 | x, (C.Sort _ | C.Meta _) | _, x ->
69 let y, context, orig =
70 if x == t1 then s, context, orig_s
71 else t, ((name,C.Decl s)::context), orig_t
73 raise (RefineFailure (lazy (localise orig,Printf.sprintf
74 "%s is expected to be a type, but its type is %s that is not a sort"
75 (NCicPp.ppterm ~subst ~metasenv ~context y)
76 (NCicPp.ppterm ~subst ~metasenv ~context x))))
79 let check_allowed_sort_elimination localise r orig =
82 | C.Appl l -> C.Appl (l @ [arg])
83 | t -> C.Appl [t;arg] in
84 (* ctx, ind_type @ lefts, sort_of_ind_ty@lefts, outsort *)
85 let rec aux metasenv subst context ind arity1 arity2 =
86 let arity1 = NCicReduction.whd ~subst context arity1 in
88 | C.Prod (name,so1,de1) (* , t ==?== C.Prod _ *) ->
89 let metasenv, meta, _ =
90 NCicMetaSubst.mk_meta metasenv ((name,C.Decl so1)::context) `Typeless
93 try NCicUnification.unify metasenv subst context
94 (C.Prod (name, so1, meta)) arity2
95 with exc -> raise (wrap_exc (lazy (localise orig, Printf.sprintf
96 "expected %s, found %s" (* XXX localizzare meglio *)
97 (NCicPp.ppterm ~subst ~metasenv ~context arity1)
98 (NCicPp.ppterm ~subst ~metasenv ~context arity2))) exc)
100 aux metasenv subst ((name, C.Decl so1)::context)
101 (mkapp (NCicSubstitution.lift 1 ind) (C.Rel 1)) de1 meta
102 | C.Sort _ (* , t ==?== C.Prod _ *) ->
103 let metasenv, meta, _ = NCicMetaSubst.mk_meta metasenv [] `Typeless in
105 (NCicPp.ppterm ~subst ~metasenv ~context (C.Prod ("_", ind, meta))) ^ " ==== " ^
106 (NCicPp.ppterm ~subst ~metasenv ~context arity2) ^ "\nMENV:\n"
107 ^ NCicPp.ppmetasenv ~subst metasenv);
108 let metasenv, subst =
109 try NCicUnification.unify metasenv subst context
110 (C.Prod ("_", ind, meta)) arity2
111 with exc -> raise (wrap_exc (lazy (localise orig, Printf.sprintf
112 "expected %s, found %s" (* XXX localizzare meglio *)
113 (NCicPp.ppterm ~subst ~metasenv ~context arity1)
114 (NCicPp.ppterm ~subst ~metasenv ~context arity2))) exc)
116 (try NCicTypeChecker.check_allowed_sort_elimination
117 ~metasenv ~subst r context ind arity1 arity2;
119 with exc -> raise (wrap_exc (lazy (localise orig,
120 "Sort elimination not allowed ")) exc))
127 ?(localise=fun _ -> Stdpp.dummy_loc) metasenv subst context term expty
129 let force_ty metasenv subst context orig t infty = function
133 | C.Lambda _ -> metasenv, subst, t, expty
135 prerr_endline ("F:" ^
136 (NCicPp.ppterm ~metasenv ~subst ~context infty) ^ " === " ^
137 (NCicPp.ppterm ~metasenv ~subst ~context expty) ^ "\nMENV:\n" ^
138 NCicPp.ppmetasenv ~subst metasenv);
139 let metasenv, subst =
140 try NCicUnification.unify metasenv subst context infty expty
141 with exc -> raise (wrap_exc (lazy (localise orig, Printf.sprintf
142 "The term %s has type %s but is here used with type %s"
143 (NCicPp.ppterm ~metasenv ~subst ~context t)
144 (NCicPp.ppterm ~metasenv ~subst ~context infty)
145 (NCicPp.ppterm ~metasenv ~subst ~context expty))) exc)
147 metasenv, subst, t, expty)
148 | None -> metasenv, subst, t, infty
150 let rec typeof_aux metasenv subst context expty =
152 prerr_endline ("R:"^NCicPp.ppterm ~metasenv ~subst ~context t);
153 let metasenv, subst, t, infty =
158 match List.nth context (n - 1) with
159 | (_,C.Decl ty) -> NCicSubstitution.lift n ty
160 | (_,C.Def (_,ty)) -> NCicSubstitution.lift n ty
162 raise (RefineFailure (lazy (localise t,"unbound variable"))))
164 metasenv, subst, t, infty
165 | C.Sort (C.Type [false,u]) -> metasenv,subst,t,(C.Sort (C.Type [true, u]))
166 | C.Sort (C.Type _) ->
167 raise (AssertFailure (lazy ("Cannot type an inferred type: "^
168 NCicPp.ppterm ~subst ~metasenv ~context t)))
169 | C.Sort _ -> metasenv,subst,t,(C.Sort (C.Type NCicEnvironment.type0))
170 | C.Implicit infos ->
171 let metasenv,t,ty = exp_implicit metasenv context expty infos in
172 metasenv, subst, t, ty
173 | C.Meta (n,l) as t ->
176 let _,_,_,ty = NCicUtils.lookup_subst n subst in ty
177 with NCicUtils.Subst_not_found _ -> try
178 let _,_,ty = NCicUtils.lookup_meta n metasenv in
179 match ty with C.Implicit _ -> assert false | _ -> ty
180 with NCicUtils.Meta_not_found _ ->
181 raise (AssertFailure (lazy (Printf.sprintf
182 "%s not found" (NCicPp.ppterm ~subst ~metasenv ~context t))))
184 metasenv, subst, t, NCicSubstitution.subst_meta l ty
186 metasenv, subst, t, NCicTypeChecker.typeof ~subst ~metasenv context t
187 | C.Prod (name,(s as orig_s),(t as orig_t)) as orig ->
188 let metasenv, subst, s, s1 = typeof_aux metasenv subst context None s in
189 let context = (name,(C.Decl s))::context in
190 let metasenv, subst, t, s2 = typeof_aux metasenv subst context None t in
191 let metasenv, subst, ty =
192 sort_of_prod localise metasenv subst
193 context orig_s orig_t (name,s) t (s1,s2)
195 metasenv, subst, orig, ty
196 | C.Lambda (n,(s as orig_s),t) ->
197 let exp_s, exp_ty_t =
201 match NCicReduction.whd ~subst context expty with
202 | C.Prod (_,s,t) -> Some s, Some t
205 let metasenv, subst, s, ty_s =
206 typeof_aux metasenv subst context None s in
207 let metasenv, subst, _ = force_to_sort metasenv subst context ty_s in
208 let (metasenv,subst), exp_ty_t =
211 (try NCicUnification.unify metasenv subst context s exp_s,exp_ty_t
212 with exc -> raise (wrap_exc (lazy (localise orig_s, Printf.sprintf
213 "Source type %s was expected to be %s" (NCicPp.ppterm ~metasenv
214 ~subst ~context s) (NCicPp.ppterm ~metasenv ~subst ~context
216 | None -> (metasenv, subst), None
218 (* XXX coerce_to_sort s *)
219 let context = (n,C.Decl s) :: context in
220 let metasenv, subst, t, ty_t =
221 typeof_aux metasenv subst context exp_ty_t t
223 metasenv, subst, C.Lambda(n,s,t), C.Prod (n,s,ty_t)
224 | C.LetIn (n,ty,t,bo) ->
225 let metasenv, subst, ty, ty_ty =
226 typeof_aux metasenv subst context None ty in
227 let metasenv, subst, _ = force_to_sort metasenv subst context ty_ty in
228 let metasenv, subst, t, _ =
229 typeof_aux metasenv subst context (Some ty) t in
230 let context = (n, C.Def (t,ty)) :: context in
231 let metasenv, subst, bo, bo_ty =
232 typeof_aux metasenv subst context expty bo
234 metasenv, subst, C.LetIn (n, ty, t, bo),
235 NCicSubstitution.subst ~avoid_beta_redexes:true t bo_ty
236 | C.Appl ((he as orig_he)::(_::_ as args)) ->
237 let metasenv, subst, he, ty_he =
238 typeof_aux metasenv subst context None he in
239 eat_prods localise metasenv subst context orig_he he ty_he args
240 | C.Appl _ -> raise (AssertFailure (lazy "Appl of length < 2"))
241 | C.Match (Ref.Ref (_,Ref.Ind (_,tyno,_)) as r,
242 outtype,(term as orig_term),pl) as orig ->
243 let _, leftno, itl, _, _ = NCicEnvironment.get_checked_indtys r in
244 let _, _, arity, cl = List.nth itl tyno in
245 let constructorsno = List.length cl in
246 let _, metasenv, args =
247 NCicMetaSubst.saturate metasenv context arity 0 in
248 let ind = if args = [] then C.Const r else C.Appl (C.Const r::args) in
249 let metasenv, subst, term, _ =
250 typeof_aux metasenv subst context (Some ind) term in
251 let metasenv, subst, outtype, outsort =
252 typeof_aux metasenv subst context None outtype in
253 let parameters, arguments = HExtlib.split_nth leftno args in
254 (* let's control if the sort elimination is allowed: [(I q1 ... qr)|B] *)
256 if parameters = [] then C.Const r
257 else C.Appl ((C.Const r)::parameters) in
258 let metasenv, subst, ind, ind_ty =
259 typeof_aux metasenv subst context None ind in
260 let metasenv, subst =
261 check_allowed_sort_elimination localise r orig_term metasenv subst
262 context ind ind_ty outsort
264 (* let's check if the type of branches are right *)
265 if List.length pl <> constructorsno then
266 raise (RefineFailure (lazy (localise orig,
267 "Wrong number of cases in a match")));
268 let _, metasenv, subst, pl_rev =
270 (fun (j, metasenv, subst, branches) p ->
272 let cons = Ref.mk_constructor j r in
273 if parameters = [] then C.Const cons
274 else C.Appl (C.Const cons::parameters)
276 let metasenv, subst, cons, ty_cons =
277 typeof_aux metasenv subst context None cons in
279 NCicTypeChecker.type_of_branch
280 ~subst context leftno outtype cons ty_cons in
281 let metasenv, subst, p, _ =
282 typeof_aux metasenv subst context (Some ty_branch) p in
283 j+1, metasenv, subst, p :: branches)
284 (1, metasenv, subst, []) pl
287 C.Match (r, outtype, term, List.rev pl_rev),
288 NCicReduction.head_beta_reduce (C.Appl (outtype::arguments@[term]))
289 | C.Match _ -> assert false
291 force_ty metasenv subst context orig t infty expty
293 typeof_aux metasenv subst context expty term
295 and eat_prods localise metasenv subst context orig_he he ty_he args =
296 let rec aux metasenv subst args_so_far ty_he = function
297 | [] -> metasenv, subst, NCic.Appl (he :: List.rev args_so_far), ty_he
299 match NCicReduction.whd ~subst context ty_he with
301 let metasenv, subst, arg, _ =
302 typeof ~localise metasenv subst context arg (Some s) in
303 let t = NCicSubstitution.subst ~avoid_beta_redexes:true arg t in
304 aux metasenv subst (arg :: args_so_far) t tl
306 let metasenv, subst, arg, ty_arg =
307 typeof ~localise metasenv subst context arg None in
308 let metasenv, meta, _ =
309 NCicMetaSubst.mk_meta metasenv
310 (("_",C.Decl ty_arg) :: context) `Type
312 let flex_prod = C.Prod ("_", ty_arg, meta) in
313 prerr_endline ("F:" ^
314 (NCicPp.ppterm ~metasenv ~subst ~context t) ^ " === " ^
315 (NCicPp.ppterm ~metasenv ~subst ~context flex_prod) ^ "\nMENV:\n" ^
316 NCicPp.ppmetasenv ~subst metasenv ^ "\nCTX:\n" ^
317 NCicPp.ppcontext ~metasenv ~subst context);
318 let metasenv, subst =
319 try NCicUnification.unify metasenv subst context t flex_prod
320 with exc -> raise (wrap_exc (lazy (localise orig_he, Printf.sprintf
321 ("The term %s is here applied to %d arguments but expects " ^^
322 "only %d arguments") (NCicPp.ppterm ~metasenv ~subst ~context he)
323 (List.length args) (List.length args_so_far))) exc)
324 (* XXX coerce to funclass *)
326 let meta = NCicSubstitution.subst ~avoid_beta_redexes:true arg meta in
327 aux metasenv subst (arg :: args_so_far) meta tl
329 aux metasenv subst [] ty_he args
331 (* vim:set foldmethod=marker: *)