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_______________________________________________________________ *)
22 module BE = BrgEnvironment
25 e: B.lenv; (* environment *)
26 s: (B.lenv * B.term) list; (* stack *)
28 d: int; (* inferred type iterations *)
29 n: int option; (* expected type iterations *)
32 type message = (rtm, B.term) L.message
34 (* Internal functions *******************************************************)
38 let sublevel = succ level
41 let s1, s2 = s ^ " in the environment", "the term" in
42 L.log st BO.specs (pred level) (L.et_items1 s1 c s2 t)
44 let log2 st s cu u ct t =
45 let s1, s2, s3 = s ^ " in the environment (expected)", "the term", "and in the environment (inferred)" in
46 L.log st BO.specs (pred level) (L.et_items2 s1 cu s2 u ~sc2:s3 ~c2:ct s2 t)
48 let rec list_and map = function
49 | hd1 :: tl1, hd2 :: tl2 ->
50 if map hd1 hd2 then list_and map (tl1, tl2) else false
56 let are_alpha_convertible err f t1 t2 =
57 let rec aux f = function
58 | B.Sort (_, p1), B.Sort (_, p2)
59 | B.LRef (_, p1), B.LRef (_, p2) ->
60 if p1 = p2 then f () else err ()
61 | B.GRef (_, u1), B.GRef (_, u2) ->
62 if U.eq u1 u2 then f () else err ()
63 | B.Cast (_, v1, t1), B.Cast (_, v2, t2)
64 | B.Appl (_, v1, t1), B.Appl (_, v2, t2) ->
65 let f _ = aux f (t1, t2) in
67 | B.Bind (_, b1, t1), B.Bind (_, b2, t2) ->
68 let f _ = aux f (t1, t2) in
71 and aux_bind f = function
72 | B.Abbr v1, B.Abbr v2 -> aux f (v1, v2)
73 | B.Abst (n1, v1), B.Abst (n2, v2) when n1 = n2 -> aux f (v1, v2)
74 | B.Void, B.Void -> f ()
77 if S.eq t1 t2 then f () else aux f (t1, t2)
79 let assert_tstep m vo = match m.n with
83 let tstep m = {m with d = succ m.d}
85 let tsteps m = match m.n with
86 | Some n when n > m.d -> n - m.d
90 let _, c, a, b = B.get m.e i in c, a, b
94 if !G.trace >= sublevel then
95 log1 st (Printf.sprintf "entering R.step: l:%u d:%i n:%s" m.l m.d (match m.n with Some n -> string_of_int n | None -> "infinite")) m.e x;
98 if assert_tstep m false then
99 step st (tstep m) (B.Sort (a, H.apply h))
102 begin match BE.get_entity uri with
103 | _, _, _, E.Abbr v ->
104 if m.n = None || !G.expand then begin
105 if !G.summary then O.add ~gdelta:1 ();
109 | _, _, _, E.Abst w ->
110 if assert_tstep m true then begin
111 if !G.summary then O.add ~grt:1 ();
119 begin match get m i with
121 if !G.summary then O.add ~ldelta:1 ();
122 step st {m with e = c} v
123 | c, a, B.Abst (_, w) ->
124 if assert_tstep m true then begin
125 if !G.summary then O.add ~lrt:1 ();
126 step st {(tstep m) with e = c} w
128 m, B.LRef (a, i), None
132 | B.Cast (_, u, t) ->
133 if assert_tstep m false then begin
134 if !G.summary then O.add ~e:1 ();
137 if !G.summary then O.add ~epsilon:1 ();
140 | B.Appl (_, v, t) ->
141 step st {m with s = (m.e, v) :: m.s} t
142 | B.Bind (a, B.Abst (n, w), t) ->
144 let n = if i = 0 then n else N.minus st n i in
145 if !G.si || N.is_not_zero st n then begin match m.s with
147 if i = 0 then m, x, None else
148 m, B.Bind (a, B.Abst (n, w), t), None
150 if !G.cc && not (N.assert_not_zero st n) then assert false;
151 if !G.summary then O.add ~beta:1 ~theta:(List.length s) ();
152 let v = if assert_tstep m false then B.Cast (E.empty_node, w, v) else v in
153 let e = B.push m.e c a (B.abbr v) in
154 step st {m with e = e; s = s} t
156 if !G.summary then O.add ~upsilon:1 ();
157 let e = B.push m.e m.e a B.Void in
158 step st {m with e = e} t
160 | B.Bind (a, b, t) ->
161 if !G.summary then O.add ~theta:(List.length m.s) ();
162 let e = B.push m.e m.e a b in
163 step st {m with e = e} t
165 let reset m ?(e=m.e) n =
166 {m with e = e; n = n; s = []; d = 0}
168 let assert_iterations m1 m2 = match m1.n, m2.n with
169 | Some n1, Some n2 -> n1 - m1.d = n2 - m2.d
173 let a, l = match b with
174 | B.Abst _ -> {a with E.n_apix = m.l}, succ m.l
177 let e = B.push m.e m.e a b in
178 {m with e = e; l = l}
180 let rec ac_nfs st (m1, t1, r1) (m2, t2, r2) =
181 if !G.trace >= level then log2 st "Now converting nfs" m1.e t1 m2.e t2;
182 match t1, r1, t2, r2 with
183 | B.Sort (_, h1), _, B.Sort (_, h2), _ ->
185 | B.LRef ({E.n_apix = e1}, _), _,
186 B.LRef ({E.n_apix = e2}, _), _ ->
187 if e1 = e2 then ac_stacks st m1 m2 else false
188 | B.GRef (_, u1), None, B.GRef (_, u2), None ->
189 if U.eq u1 u2 && assert_iterations m1 m2 then ac_stacks st m1 m2 else false
190 | B.GRef ({E.n_apix = e1}, u1), Some v1,
191 B.GRef ({E.n_apix = e2}, u2), Some v2 ->
192 if e1 < e2 then begin
193 if !G.summary then O.add ~gdelta:1 ();
194 ac_nfs st (m1, t1, r1) (step st m2 v2)
195 end else if e2 < e1 then begin
196 if !G.summary then O.add ~gdelta:1 ();
197 ac_nfs st (step st m1 v1) (m2, t2, r2)
198 end else if U.eq u1 u2 && assert_iterations m1 m2 && ac_stacks st m1 m2 then true
200 if !G.summary then O.add ~gdelta:2 ();
203 | _, _, B.GRef _, Some v2 ->
204 if !G.summary then O.add ~gdelta:1 ();
205 ac_nfs st (m1, t1, r1) (step st m2 v2)
206 | B.GRef _, Some v1, _, _ ->
207 if !G.summary then O.add ~gdelta:1 ();
208 ac_nfs st (step st m1 v1) (m2, t2, r2)
209 | B.Bind (a1, (B.Abst (n1, w1) as b1), t1), _,
210 B.Bind (a2, (B.Abst (n2, w2) as b2), t2), _ ->
211 if ((!G.cc && N.assert_equal st n1 n2) || N.are_equal st n1 n2) &&
212 ac st (reset m1 zero) w1 (reset m2 zero) w2
213 then ac st (push m1 a1 b1) t1 (push m2 a2 b2) t2
215 | B.Sort _, _, B.Bind (a, B.Abst (n, _), t), _ ->
217 if !G.cc && not (N.assert_zero st n) then false else begin
218 if !G.summary then O.add ~upsilon:1 ();
219 ac st (push m1 a B.Void) t1 (push m2 a B.Void) t end
223 and ac st m1 t1 m2 t2 =
224 (* L.warn "entering R.are_convertible"; *)
225 ac_nfs st (step st m1 t1) (step st m2 t2)
227 and ac_stacks st m1 m2 =
228 (* L.warn "entering R.are_convertible_stacks"; *)
229 if List.length m1.s <> List.length m2.s then false else
230 let map (c1, v1) (c2, v2) =
231 let m1, m2 = reset m1 ~e:c1 zero, reset m2 ~e:c2 zero in
234 list_and map (m1.s, m2.s)
236 (* Interface functions ******************************************************)
239 e = B.empty; s = []; l = 0; d = 0; n = None
244 let _, _, _, b = B.get m.e i in b
247 if !G.trace >= level then log1 st "Now scanning" m.e t;
248 let m, t, _ = step st (reset m n) t in
251 let are_convertible st m1 n1 t1 m2 n2 t2 =
252 if !G.trace >= level then log2 st "Now converting" m1.e t1 m2.e t2;
253 let r = ac st (reset m1 n1) t1 (reset m2 n2) t2 in
256 if S.eq mu mw then are_alpha_convertible err f u w else err () *)
258 (* error reporting **********************************************************)
260 let pp_term st m och t = BO.specs.L.pp_term st m.e och t
262 let pp_lenv st och m = BO.specs.L.pp_lenv st och m.e
265 L.pp_term = pp_term; L.pp_lenv = pp_lenv