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1 (**************************************************************************)
2 (*       ___                                                              *)
3 (*      ||M||                                                             *)
4 (*      ||A||       A project by Andrea Asperti                           *)
5 (*      ||T||                                                             *)
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9 (*      \   /                                                             *)
10 (*       \ /        This file is distributed under the terms of the       *)
11 (*        v         GNU General Public License Version 2                  *)
12 (*                                                                        *)
13 (**************************************************************************)
14
15 include "hints_declaration.ma".
16 include "logic/equality.ma".
17 include "sets/setoids.ma".
18
19 ninductive nat: Type[0] ≝
20    O: nat
21  | S: nat → nat.
22
23 ndefinition NAT: setoid.
24  napply mk_setoid [ napply nat | napply EQ]
25 nqed.
26
27 alias symbol "hint_decl" = "hint_decl_Type1".
28 unification hint 0 ≔ ⊢ carr NAT ≡ nat.