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_______________________________________________________________ *)
23 module BE = BrgEnvironment
26 e: B.lenv; (* environment *)
27 s: (B.lenv * B.term) list; (* stack *)
29 d: int; (* inferred type iterations *)
30 n: int option; (* expected type iterations *)
33 type message = (kam, B.term) L.message
35 (* Internal functions *******************************************************)
39 let sublevel = succ level
42 let s1, s2 = s ^ " in the environment", "the term" in
43 L.log st BO.specs level (L.et_items1 s1 c s2 t)
45 let log2 st s cu u ct t =
46 let s1, s2, s3 = s ^ " in the environment (expected)", "the term", "and in the environment (inferred)" in
47 L.log st BO.specs level (L.et_items2 s1 cu s2 u ~sc2:s3 ~c2:ct s2 t)
49 let rec list_and map = function
50 | hd1 :: tl1, hd2 :: tl2 ->
51 if map hd1 hd2 then list_and map (tl1, tl2) else false
57 let are_alpha_convertible err f t1 t2 =
58 let rec aux f = function
59 | B.Sort (_, p1), B.Sort (_, p2)
60 | B.LRef (_, p1), B.LRef (_, p2) ->
61 if p1 = p2 then f () else err ()
62 | B.GRef (_, u1), B.GRef (_, u2) ->
63 if U.eq u1 u2 then f () else err ()
64 | B.Cast (_, v1, t1), B.Cast (_, v2, t2)
65 | B.Appl (_, v1, t1), B.Appl (_, v2, t2) ->
66 let f _ = aux f (t1, t2) in
68 | B.Bind (_, b1, t1), B.Bind (_, b2, t2) ->
69 let f _ = aux f (t1, t2) in
72 and aux_bind f = function
73 | B.Abbr v1, B.Abbr v2 -> aux f (v1, v2)
74 | B.Abst (n1, v1), B.Abst (n2, v2) when n1 = n2 -> aux f (v1, v2)
75 | B.Void, B.Void -> f ()
78 if W.eq t1 t2 then f () else aux f (t1, t2)
80 let assert_tstep m vo = match m.n with
84 let tstep m = {m with d = succ m.d}
86 let tsteps m = match m.n with
87 | Some n when n > m.d -> n - m.d
91 let _, c, a, b = B.get m.e i in c, a, b
95 if !G.trace >= sublevel then
96 log1 st.S.lenv (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;
99 if assert_tstep m false then
100 step st (tstep m) (B.Sort (a, H.apply h))
103 begin match BE.get_entity uri with
104 | _, _, _, E.Abbr v ->
105 if st.S.delta then begin
106 if !G.summary then O.add ~gdelta:1 ();
110 | _, _, _, E.Abst w ->
111 if assert_tstep m true then begin
112 if !G.summary then O.add ~grt:1 ();
120 begin match get m i with
122 if !G.summary then O.add ~ldelta:1 ();
123 step st {m with e = c} v
124 | c, a, B.Abst (_, w) ->
125 if assert_tstep m true then begin
126 if !G.summary then O.add ~lrt:1 ();
127 step st {(tstep m) with e = c} w
129 m, B.LRef (a, i), None
133 | B.Cast (_, u, t) ->
134 if assert_tstep m false then begin
135 if !G.summary then O.add ~e:1 ();
138 if !G.summary then O.add ~epsilon:1 ();
141 | B.Appl (_, v, t) ->
142 step st {m with s = (m.e, v) :: m.s} t
143 | B.Bind (a, B.Abst (n, w), t) ->
147 if i = 0 then m, x, None else
148 let n = N.minus st.S.lenv n i in
149 m, B.Bind (a, B.Abst (n, w), t), None
151 if !G.cc && not (N.assert_not_zero st.S.lenv n) then assert false;
152 if !G.summary then O.add ~beta:1 ~theta:(List.length s) ();
153 let v = if assert_tstep m false then B.Cast (E.empty_node, w, v) else v in
154 let e = B.push m.e c a (B.abbr v) in
155 step st {m with e = e; s = s} t
157 | B.Bind (a, b, t) ->
158 if !G.summary then O.add ~theta:(List.length m.s) ();
159 let e = B.push m.e m.e a b in
160 step st {m with e = e} t
162 let reset m ?(e=m.e) n =
163 {m with e = e; n = n; s = []; d = 0}
165 let assert_iterations m1 m2 = match m1.n, m2.n with
166 | Some n1, Some n2 -> n1 - m1.d = n2 - m2.d
170 let a, l = match b with
171 | B.Abst _ -> {a with E.n_apix = Some m.l}, succ m.l
174 let e = B.push m.e m.e a b in
175 {m with e = e; l = l}
177 let rec ac_nfs st (m1, t1, r1) (m2, t2, r2) =
178 if !G.trace >= level then log2 st.S.lenv "Now converting nfs" m1.e t1 m2.e t2;
179 match t1, r1, t2, r2 with
180 | B.Sort (_, h1), _, B.Sort (_, h2), _ ->
182 | B.LRef ({E.n_apix = Some e1}, _), _,
183 B.LRef ({E.n_apix = Some e2}, _), _ ->
184 if e1 = e2 then ac_stacks st m1 m2 else false
185 | B.GRef (_, u1), None, B.GRef (_, u2), None ->
186 if U.eq u1 u2 && assert_iterations m1 m2 then ac_stacks st m1 m2 else false
187 | B.GRef ({E.n_apix = Some e1}, u1), Some v1,
188 B.GRef ({E.n_apix = Some e2}, u2), Some v2 ->
189 if e1 < e2 then begin
190 if !G.summary then O.add ~gdelta:1 ();
191 ac_nfs st (m1, t1, r1) (step st m2 v2)
192 end else if e2 < e1 then begin
193 if !G.summary then O.add ~gdelta:1 ();
194 ac_nfs st (step st m1 v1) (m2, t2, r2)
195 end else if U.eq u1 u2 && assert_iterations m1 m2 && ac_stacks st m1 m2 then true
197 if !G.summary then O.add ~gdelta:2 ();
200 | _, _, B.GRef _, Some v2 ->
201 if !G.summary then O.add ~gdelta:1 ();
202 ac_nfs st (m1, t1, r1) (step st m2 v2)
203 | B.GRef _, Some v1, _, _ ->
204 if !G.summary then O.add ~gdelta:1 ();
205 ac_nfs st (step st m1 v1) (m2, t2, r2)
206 | B.Bind (a1, (B.Abst (n1, w1) as b1), t1), _,
207 B.Bind (a2, (B.Abst (n2, w2) as b2), t2), _ ->
208 if !G.cc && not (N.assert_equal st.S.lenv n1 n2) then false else
209 if ac {st with S.si = false} (reset m1 zero) w1 (reset m2 zero) w2 then
210 ac st (push m1 a1 b1) t1 (push m2 a2 b2) t2
212 | B.Sort _, _, B.Bind (a, (B.Abst (n, _) as b), t), _ ->
214 if !G.cc && not (N.assert_zero st.S.lenv n) then false else begin
215 if !G.summary then O.add ~si:1 ();
216 ac st (push m1 a b) t1 (push m2 a b) t end
220 and ac st m1 t1 m2 t2 =
221 (* L.warn "entering R.are_convertible"; *)
222 ac_nfs st (step st m1 t1) (step st m2 t2)
224 and ac_stacks st m1 m2 =
225 (* L.warn "entering R.are_convertible_stacks"; *)
226 if List.length m1.s <> List.length m2.s then false else
227 let map (c1, v1) (c2, v2) =
228 let m1, m2 = reset m1 ~e:c1 zero, reset m2 ~e:c2 zero in
229 ac {st with S.si = false} m1 v1 m2 v2
231 list_and map (m1.s, m2.s)
233 (* Interface functions ******************************************************)
236 e = B.empty; s = []; l = 0; d = 0; n = None
241 let _, _, _, b = B.get m.e i in b
244 if !G.trace >= level then log1 st.S.lenv "Now scanning" m.e t;
245 let m, t, _ = step {st with S.delta = true} (reset m n) t in
248 let are_convertible st m1 n1 t1 m2 n2 t2 =
249 if !G.trace >= level then log2 st.S.lenv "Now converting" m1.e t1 m2.e t2;
250 let r = ac {st with S.delta = !G.expand} (reset m1 n1) t1 (reset m2 n2) t2 in
253 if W.eq mu mw then are_alpha_convertible err f u w else err () *)
255 (* error reporting **********************************************************)
257 let pp_term st m och t = BO.specs.L.pp_term st m.e och t
259 let pp_lenv st och m = BO.specs.L.pp_lenv st och m.e
262 L.pp_term = pp_term; L.pp_lenv = pp_lenv