Well, in this case I don't really see the advantage of using sets. The 
only difference it makes is that arr_1 | arr_2 becomes 
set_1.merge(set_2).

So unless you plan to actually use the special features of sets, I'd 
stick with standard arrays.

But I don't want this to turn into yet another endless discussion about 
implementation details, so do whatever you think fits best.

-- 
Posted via http://www.ruby-forum.com/.