The meaning of "equivalent" cannot be precisely defined but the intent is that two objects are
considered equivalent if they can be used interchangeably. Conforming protocols may choose to
more precisely define the meaning of "equivalent���.
Can you provide a reference for your assertion that objects must be of the same class in order to be equivalent?How about other comparisons between objects of different classes? Is 1.9 < 2? Is 2.1 > 2? How about 2.0 = 2? Is #a < ���b���? is #b > ���a���? How about #a = ���a���? It seems strange to suggest that an object can be less than or greater than, but not equal to!