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4 (* ||A|| A project by Andrea Asperti *)
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7 (* ||T|| The HELM team. *)
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15 include "logic/pts.ma".
17 inductive bool: Type[0] ≝ true: bool | false: bool.
19 definition orb ≝ λa,b:bool. match a with [ true ⇒ true | _ ⇒ b ].
21 notation "a || b" left associative with precedence 30 for @{'orb $a $b}.
22 interpretation "orb" 'orb a b = (orb a b).