Order Order Order type Order = {#less; #equal; #greater} A type to represent an order. isLess func isLess(order : Order) : Bool Check if an order is #less. isEqual func isEqual(order : Order) : Bool Check if an order is #equal. isGreater func isGreater(order : Order) : Bool Check if an order is #greater. equal func equal(o1 : Order, o2 : Order) : Bool Returns true if only if o1 and o2 are the same ordering.