(* *)
(**************************************************************************)
-set "baseuri" "cic:/matita/nat/nat".
-
include "higher_order_defs/functions.ma".
inductive nat : Set \def
| O : nat
| S : nat \to nat.
+interpretation "Natural numbers" 'N = nat.
+
definition pred: nat \to nat \def
\lambda n:nat. match n with
[ O \Rightarrow O