--- /dev/null
+(*
+ ||M|| This file is part of HELM, an Hypertextual, Electronic
+ ||A|| Library of Mathematics, developed at the Computer Science
+ ||T|| Department, University of Bologna, Italy.
+ ||I||
+ ||T|| HELM is free software; you can redistribute it and/or
+ ||A|| modify it under the terms of the GNU General Public License
+ \ / version 2 or (at your option) any later version.
+ \ / This software is distributed as is, NO WARRANTY.
+ V_______________________________________________________________ *)
+
+module U = NUri
+module C = Cps
+module W = Share
+module L = Log
+module H = Hierarchy
+module E = Entity
+module N = Level
+module B = Brg
+module BE = BrgEnvironment
+module BS = BrgSubstitution
+module BR = BrgReduction
+
+type message = (BR.kam, B.term) Log.message
+
+(* Internal functions *******************************************************)
+
+let level = 4
+
+let message1 st1 m t1 =
+ L.et_items1 "In the environment" m st1 t1
+
+let log1 s m t =
+ let s = s ^ " the term" in
+ L.log BR.specs level (message1 s m t)
+
+let error1 err s m t =
+ err (message1 s m t)
+
+let message3 m t1 t2 ?mu t3 =
+ let sm, st1, st2 = "In the environment", "the term", "is of type" in
+ match mu with
+ | Some mu ->
+ let smu, st3 = "but in the environment", "it must be of type" in
+ L.et_items3 sm m st1 t1 st2 t2 ~sc3:smu ~c3:mu st3 t3
+ | None ->
+ let st3 = "but it must be of type" in
+ L.et_items3 sm m st1 t1 st2 t2 st3 t3
+
+let error3 err m t1 t2 ?mu t3 =
+ err (message3 m t1 t2 ?mu t3)
+
+let assert_convertibility err f st m u w v =
+ if BR.are_convertible st m u m w then f () else
+ error3 err m v w u
+
+let assert_applicability err f st m u w v =
+ match BR.xwhd st m u with
+ | _, B.Sort _ ->
+ error1 err "not a function type" m u
+ | mu, B.Bind (_, B.Abst (_, u), _) ->
+ if BR.are_convertible st mu u m w then f () else
+ error3 err m v w ~mu u
+ | _ -> assert false (**)
+
+let rec b_type_of err f st m x =
+ log1 "Now checking" m x;
+ match x with
+ | B.Sort (a, h) ->
+ let h = H.apply h in f x (B.Sort (a, h))
+ | B.LRef (_, i) ->
+ begin match BR.get m i with
+ | B.Abst (_, w) ->
+ f x (BS.lift (succ i) (0) w)
+ | B.Abbr (B.Cast (_, w, _)) ->
+ f x (BS.lift (succ i) (0) w)
+ | B.Abbr _ -> assert false
+ | B.Void ->
+ error1 err "reference to excluded variable" m x
+ end
+ | B.GRef (_, uri) ->
+ begin match BE.get_entity uri with
+ | _, _, E.Abst (_, w) -> f x w
+ | _, _, E.Abbr (B.Cast (_, w, _)) -> f x w
+ | _, _, E.Abbr _ -> assert false
+ | _, _, E.Void ->
+ error1 err "reference to unknown entry" m x
+ end
+ | B.Bind (a, B.Abbr v, t) ->
+ let f xv xt tt =
+ f (W.sh2 v xv t xt x (B.bind_abbr a)) (B.bind_abbr a xv tt)
+ in
+ let f xv m = b_type_of err (f xv) st m t in
+ let f xv = f xv (BR.push m a (B.abbr xv)) in
+ let f xv vv = match xv with
+ | B.Cast _ -> f xv
+ | _ -> f (B.Cast ([], vv, xv))
+ in
+ type_of err f st m v
+ | B.Bind (a, B.Abst (n, u), t) ->
+ let f xu xt tt =
+ f (W.sh2 u xu t xt x (B.bind_abst n a)) (B.bind_abst (N.pred n) a xu tt)
+ in
+ let f xu m = b_type_of err (f xu) st m t in
+ let f xu _ = f xu (BR.push m a (B.abst n xu)) in
+ type_of err f st m u
+ | B.Bind (a, B.Void, t) ->
+ let f xt tt =
+ f (W.sh1 t xt x (B.bind_void a)) (B.bind_void a tt)
+ in
+ b_type_of err f st (BR.push m a B.Void) t
+
+ | B.Appl (a, v, t) ->
+ let f xv vv xt tt =
+ let f _ = f (W.sh2 v xv t xt x (B.appl a)) (B.appl a xv tt) in
+ assert_applicability err f st m tt vv xv
+ in
+ let f xv vv = b_type_of err (f xv vv) st m t in
+ type_of err f st m v
+ | B.Cast (a, u, t) ->
+ let f xu xt tt =
+ let f _ = f (W.sh2 u xu t xt x (B.cast a)) xu in
+ assert_convertibility err f st m xu tt xt
+ in
+ let f xu _ = b_type_of err (f xu) st m t in
+ type_of err f st m u
+
+(* Interface functions ******************************************************)
+
+and type_of err f st m x =
+ let f t u = L.unbox level; f t u in
+ L.box level; b_type_of err f st m x
projects / helm.git / blobdiff