Why = and hash go hand-in-hand:

If you want two things to be considered equal, and you want to put
them in a collection, and that collection uses hashing, then you have
to ensure they will hash to the same key.

-- 
Patrick Logan                 mailto:patrickl at gemstone.com
Voice 503-533-3365            Fax   503-629-8556
Gemstone Systems, Inc         http://www.gemstone.com