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 ZE = BagEnvironment
23 module ZR = BagReduction
25 (* Internal functions *******************************************************)
30 let s1, s2 = s ^ " in the envireonment", "the term" in
31 L.log st ZO.specs level (L.et_items1 s1 c s2 t)
33 let error1 err st c t =
34 let sc = "In the envireonment" in
35 err (L.et_items1 sc c st t)
37 let error3 err c t1 t2 t3 =
38 let sc, st1, st2, st3 =
39 "In the envireonment", "the term", "is of type", "but must be of type"
41 err (L.et_items3 sc c st1 t1 st2 t2 st3 t3)
44 let map t v = Z.Appl (v, t) in
45 List.fold_left map (Z.GRef u) l
47 let rec b_type_of err f st c x =
48 (* L.warn "Entering T.b_type_of"; *)
49 if !G.trace >= level then log1 st.S.lenv "Now checking" c x;
52 let h = H.apply h in f x (Z.Sort h)
54 let err0 () = error1 err "variable not found" c x in
57 | Z.Abbr (Z.Cast (w, v)) -> f x w
58 | Z.Abbr _ -> assert false
59 | Z.Void -> error1 err "reference to excluded variable" c x
64 | _, _, _, E.Abst w -> f x w
65 | _, _, _, E.Abbr (Z.Cast (w, v)) -> f x w
66 | _, _, _, E.Abbr _ -> assert false
67 | _, _, _, E.Void -> assert false
70 | Z.Bind (a, l, Z.Abbr v, t) ->
72 f (W.sh2 v xv t xt x (Z.bind_abbr a l)) (Z.bind_abbr a l xv tt)
74 let f xv cc = b_type_of err (f xv) st cc t in
75 let f xv = Z.push "type abbr" (f xv) c a l (Z.Abbr xv) in
76 let f xv vv = match xv with
78 | _ -> f (Z.Cast (vv, xv))
81 | Z.Bind (a, l, Z.Abst u, t) ->
83 f (W.sh2 u xu t xt x (Z.bind_abst a l)) (Z.bind_abst a l xu tt)
85 let f xu cc = b_type_of err (f xu) st cc t in
86 let f xu _ = Z.push "type abst" (f xu) c a l (Z.Abst xu) in
88 | Z.Bind (a, l, Z.Void, t) ->
90 f (W.sh1 t xt x (Z.bind a l Z.Void)) (Z.bind a l Z.Void tt)
92 let f cc = b_type_of err f st cc t in
93 Z.push "type void" f c a l Z.Void
95 let f xv vv xt tt = function
97 if !G.trace > level then L.log st.S.lenv ZO.specs (succ level) (L.t_items1 "Just scanned" c w);
99 (* L.warn (Printf.sprintf "Convertible: %b" a); *)
100 if a then f (W.sh2 v xv t xt x Z.appl) (Z.appl xv tt)
101 else error3 err c xv vv w
103 ZR.are_convertible f st c w vv
105 error1 err "not a function" c xt
107 let f xv vv xt tt = ZR.ho_whd (f xv vv xt tt) st c tt in
108 let f xv vv = b_type_of err (f xv vv) st c t in
112 (* L.warn (Printf.sprintf "Convertible: %b" a); *)
113 if a then f (W.sh2 u xu t xt x Z.cast) xu else error3 err c xt tt xu
115 let f xu xt tt = ZR.are_convertible (f xu xt tt) st c xu tt in
116 let f xu _ = b_type_of err (f xu) st c t in
119 (* Interface functions ******************************************************)
121 and type_of err f st c x = b_type_of err f st c x