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_______________________________________________________________ *)
21 module ZE = BagEnvironment
22 module ZR = BagReduction
24 (* Internal functions *******************************************************)
29 let s1, s2 = s ^ " in the envireonment", "the term" in
30 L.log st ZO.specs (pred level) (L.et_items1 s1 c s2 t)
32 let error1 err st c t =
33 let sc = "In the envireonment" in
34 err (L.et_items1 sc c st t)
36 let error3 err c t1 t2 t3 =
37 let sc, st1, st2, st3 =
38 "In the envireonment", "the term", "is of type", "but must be of type"
40 err (L.et_items3 sc c st1 t1 st2 t2 st3 t3)
43 let map t v = Z.Appl (v, t) in
44 List.fold_left map (Z.GRef u) l
46 let rec b_type_of err f st c x =
47 (* L.warn "Entering T.b_type_of"; *)
48 if !G.ct >= level then log1 st "Now checking" c x;
51 let h = H.apply h in f x (Z.Sort h)
53 let err0 () = error1 err "variable not found" c x in
56 | Z.Abbr (Z.Cast (w, v)) -> f x w
57 | Z.Abbr _ -> assert false
58 | Z.Void -> error1 err "reference to excluded variable" c x
63 | _, _, _, E.Abst w -> f x w
64 | _, _, _, E.Abbr (Z.Cast (w, v)) -> f x w
65 | _, _, _, E.Abbr _ -> assert false
66 | _, _, _, E.Void -> assert false
69 | Z.Bind (a, l, Z.Abbr v, t) ->
71 f (S.sh2 v xv t xt x (Z.bind_abbr a l)) (Z.bind_abbr a l xv tt)
73 let f xv cc = b_type_of err (f xv) st cc t in
74 let f xv = Z.push "type abbr" (f xv) c a l (Z.Abbr xv) in
75 let f xv vv = match xv with
77 | _ -> f (Z.Cast (vv, xv))
80 | Z.Bind (a, l, Z.Abst u, t) ->
82 f (S.sh2 u xu t xt x (Z.bind_abst a l)) (Z.bind_abst a l xu tt)
84 let f xu cc = b_type_of err (f xu) st cc t in
85 let f xu _ = Z.push "type abst" (f xu) c a l (Z.Abst xu) in
87 | Z.Bind (a, l, Z.Void, t) ->
89 f (S.sh1 t xt x (Z.bind a l Z.Void)) (Z.bind a l Z.Void tt)
91 let f cc = b_type_of err f st cc t in
92 Z.push "type void" f c a l Z.Void
94 let f xv vv xt tt = function
96 if !G.ct > level then L.log st ZO.specs level (L.t_items1 "Just scanned" c w);
98 (* L.warn (Printf.sprintf "Convertible: %b" a); *)
99 if a then f (S.sh2 v xv t xt x Z.appl) (Z.appl xv tt)
100 else error3 err c xv vv w
102 ZR.are_convertible f st c w vv
104 error1 err "not a function" c xt
106 let f xv vv xt tt = ZR.ho_whd (f xv vv xt tt) st c tt in
107 let f xv vv = b_type_of err (f xv vv) st c t in
111 (* L.warn (Printf.sprintf "Convertible: %b" a); *)
112 if a then f (S.sh2 u xu t xt x Z.cast) xu else error3 err c xt tt xu
114 let f xu xt tt = ZR.are_convertible (f xu xt tt) st c xu tt in
115 let f xu _ = b_type_of err (f xu) st c t in
118 (* Interface functions ******************************************************)
120 and type_of err f st c x = b_type_of err f st c x