1 (* Copyright (C) 2004-2005, HELM Team.
3 * This file is part of HELM, an Hypertextual, Electronic
4 * Library of Mathematics, developed at the Computer Science
5 * Department, University of Bologna, Italy.
7 * HELM is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
12 * HELM is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with HELM; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
22 * For details, see the HELM World-Wide-Web page,
23 * http://helm.cs.unibo.it/
28 exception Value_not_found of string
32 | StringValue of string
34 | OptValue of value option
35 | ListValue of value list
41 | OptType of value_type
42 | ListType of value_type
44 type declaration = string * value_type
45 type binding = string * (value_type * value)
46 type t = (string * (value_type * value)) list
48 let lookup_value env name =
50 snd (List.assoc name env)
51 with Not_found -> raise (Value_not_found name)
53 let remove env name = List.remove_assoc name env
55 let lookup_term env name =
56 match lookup_value env name with
58 | _ -> raise (Value_not_found name)
60 let lookup_num env name =
61 match lookup_value env name with
63 | _ -> raise (Value_not_found name)
65 let lookup_string env name =
66 match lookup_value env name with
68 | _ -> raise (Value_not_found name)
70 let opt_binding_some (n, (ty, v)) = (n, (OptType ty, OptValue (Some v)))
71 let opt_binding_none (n, (ty, v)) = (n, (OptType ty, OptValue None))
72 let opt_binding_of_name (n, ty) = (n, (OptType ty, OptValue None))
73 let list_binding_of_name (n, ty) = (n, (ListType ty, ListValue []))
74 let opt_declaration (n, ty) = (n, OptType ty)
75 let list_declaration (n, ty) = (n, ListType ty)
77 let declaration_of_var = function
78 | NumVar s -> s, NumType
79 | IdentVar s -> s, StringType
80 | TermVar s -> s, TermType
83 let value_of_term = function
84 | Num (s, _) -> NumValue s
85 | Ident (s, None) -> StringValue s
88 let term_of_value = function
89 | NumValue s -> Num (s, 0)
90 | StringValue s -> Ident (s, None)
92 | _ -> assert false (* TO BE UNDERSTOOD *)
94 let rec well_typed ty value =
96 | TermType, TermValue _
97 | StringType, StringValue _
98 | OptType _, OptValue None
99 | NumType, NumValue _ -> true
100 | OptType ty', OptValue (Some value') -> well_typed ty' value'
101 | ListType ty', ListValue vl ->
102 List.for_all (fun value' -> well_typed ty' value') vl
105 let declarations_of_env = List.map (fun (name, (ty, _)) -> (name, ty))
107 let coalesce_env declarations env_list =
108 let env0 = List.map list_binding_of_name declarations in
109 let grow_env_entry env n v =
112 | (n', (ty, ListValue vl)) as entry ->
113 if n' = n then n', (ty, ListValue (v :: vl)) else entry
117 let grow_env env_i env =
119 (fun env (n, (_, v)) -> grow_env_entry env n v)
122 List.fold_right grow_env env_list env0