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_______________________________________________________________ *)
12 (* kernel version: basic, absolute, global *)
13 (* note : experimental *)
20 type bind = Void (* exclusion *)
21 | Abst of term (* abstraction *)
22 | Abbr of term (* abbreviation *)
24 and term = Sort of int (* hierarchy index *)
25 | LRef of int (* location *)
26 | GRef of uri (* reference *)
27 | Cast of term * term (* domain, element *)
28 | Appl of term * term (* argument, function *)
29 | Bind of attrs * int * bind * term (* name, location, binder, scope *)
31 type entity = term E.entity (* attrs, uri, binder *)
33 type lenv = (attrs * int * bind) list (* location, name, binder *)
35 type message = (lenv, term) Log.item list
37 (* Currified constructors ***************************************************)
45 let cast u t = Cast (u, t)
47 let appl u t = Appl (u, t)
49 let bind a l b t = Bind (a, l, b, t)
51 let bind_abst a l u t = Bind (a, l, Abst u, t)
53 let bind_abbr a l v t = Bind (a, l, Abbr v, t)
55 (* local environment handling functions *************************************)
59 let push msg f es a l b =
60 let rec does_not_occur loc = function
62 | (_, l, _) :: _ when l = loc -> false
63 | _ :: es -> does_not_occur l es
65 if not (does_not_occur l es) then failwith msg else
66 let c = (a, l, b) :: es in f c
68 let append f es1 es2 =
69 f (List.append es2 es1)
74 let contents f es = f es
77 let rec aux = function
79 | (a, l, b) :: tl -> if l = i then f a b else aux tl
84 let rec aux n = function
86 | (_, l, _) :: _ when l = loc -> f n
87 | _ :: e -> aux (succ n) e