On Fri, 27 Jun 2003 10:48:56 +0900, Krishna Dole wrote: > Hi, > I'm having trouble using the & (intersection) method on two arrays of > objects. I know that if the objects don't have comparison methods, & won't > work because it is looking at the object IDs rather than values stored in > the objects, but I can't seem to get & to use the comparison methods I want. > [snip code] > p (foo & bar) # returns an empty array! NOOOOO!!!!! There is no intersection(&) method. I guess you have to do def &(anOther) @n & anOther.n end Have you looked at 'set.rb' which is distributed with ruby ? -- Simon Strandgaard