include "higher_order_defs/functions.ma".
-theorem esempio: \forall A,B,C:Prop.(A \to B \to C) \to (A \to B)
-\to A \to C.
-
-
-
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