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_______________________________________________________________ *)
19 module E = BagEnvironment
20 module R = BagReduction
22 exception TypeError of B.message
24 (* Internal functions *******************************************************)
29 let sc, st = s ^ " in the context", "the term" in
30 L.log O.specs level (L.ct_items1 sc c st t)
33 let sc = "In the context" in
34 raise (TypeError (L.ct_items1 sc c st t))
36 let error3 c t1 t2 t3 =
37 let sc, st1, st2, st3 =
38 "In the context", "the term", "is of type", "but must be of type"
40 raise (TypeError (L.ct_items3 sc c st1 t1 st2 t2 st3 t3))
43 let map t v = B.Appl (v, t) in
44 List.fold_left map (B.GRef u) l
46 (* Interface functions ******************************************************)
48 let rec b_type_of f g c x =
49 (* L.warn "Entering T.b_type_of"; *)
50 log1 "Now checking" c x;
53 let f h = f x (B.Sort h) in H.apply f g h
56 | Some (_, B.Abst w) -> f x w
57 | Some (_, B.Abbr (B.Cast (w, v))) -> f x w
58 | Some (_, B.Abbr _) -> assert false
60 error1 "reference to excluded variable" c x
62 error1 "variable not found" c x
67 | _, _, B.Abst w -> f x w
68 | _, _, B.Abbr (B.Cast (w, v)) -> f x w
69 | _, _, B.Abbr _ -> assert false
71 error1 "reference to excluded object" c x
74 | B.Bind (l, id, B.Abbr v, t) ->
76 f (S.sh2 v xv t xt x (B.bind_abbr l id)) (B.bind_abbr l id xv tt)
78 let f xv cc = b_type_of (f xv) g cc t in
79 let f xv = B.push "type abbr" (f xv) c l id (B.Abbr xv) in
80 let f xv vv = match xv with
82 | _ -> f (B.Cast (vv, xv))
85 | B.Bind (l, id, B.Abst u, t) ->
87 f (S.sh2 u xu t xt x (B.bind_abst l id)) (B.bind_abst l id xu tt)
89 let f xu cc = b_type_of (f xu) g cc t in
90 let f xu _ = B.push "type abst" (f xu) c l id (B.Abst xu) in
92 | B.Bind (l, id, B.Void, t) ->
94 f (S.sh1 t xt x (B.bind l id B.Void)) (B.bind l id B.Void tt)
96 let f cc = b_type_of f g cc t in
97 B.push "type void" f c l id B.Void
99 let f xv vv xt tt = function
102 L.log O.specs (succ level) (L.t_items1 "Just scanned" c w);
103 L.unbox (succ level);
105 (* L.warn (Printf.sprintf "Convertible: %b" a); *)
106 if a then f (S.sh2 v xv t xt x B.appl) (B.appl xv tt)
107 else error3 c xv vv w
109 R.are_convertible f c w vv
111 error1 "not a function" c xt
113 let f xv vv xt tt = R.ho_whd (f xv vv xt tt) c tt in
114 let f xv vv = b_type_of (f xv vv) g c t in
118 (* L.warn (Printf.sprintf "Convertible: %b" a); *)
119 if a then f (S.sh2 u xu t xt x B.cast) xu else error3 c xt tt xu
121 let f xu xt tt = R.are_convertible (f xu xt tt) c xu tt in
122 let f xu _ = b_type_of (f xu) g c t in
125 and type_of f g c x =
126 let f t u = L.unbox level; f t u in
127 L.box level; b_type_of f g c x