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cicNotationUtil: in fresh_name_generator, "\eta" replaced with "eta", which is an...
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1 (**************************************************************************)
2 (*       ___                                                              *)
3 (*      ||M||                                                             *)
4 (*      ||A||       A project by Andrea Asperti                           *)
5 (*      ||T||                                                             *)
6 (*      ||I||       Developers:                                           *)
7 (*      ||T||         The HELM team.                                      *)
8 (*      ||A||         http://helm.cs.unibo.it                             *)
9 (*      \   /                                                             *)
10 (*       \ /        This file is distributed under the terms of the       *)
11 (*        v         GNU General Public License Version 2                  *)
12 (*                                                                        *)
13 (**************************************************************************)
14
15 include "nat/nat.ma".
16 include "logic/cprop_connectives.ma".
17
18 definition hide ≝ λT:Type.λx:T.x.
19
20 notation < "\blacksquare" non associative with precedence 50 for @{'hide}.
21 interpretation "hide" 'hide = (hide _ _).
22 interpretation "hide2" 'hide = (hide _ _ _).
23
24 definition inject ≝ λP.λa:nat.λp:P a. ex_introT ? P ? p.
25 coercion inject 0 1.
26 definition eject ≝ λP.λc: ∃n:nat.P n. match c with [ ex_introT w _ ⇒ w].
27 coercion eject.