From: "Peña, Botp" <botp@...>
Date: 2007-08-21T17:16:52+09:00
Subject: Re: Detecting duplicates in an array, anything in the standa

From: Jimmy Kofler [mailto:koflerjim@mailinator.com] 
#     uniq.map {|v| (self - [v]).size < (self.size - 1) ? v : nil}.compact

cool.
could we simplify it like,

irb(main):014:0> a
=> [1, 1, 2, 2, 2, 4, 3]
irb(main):015:0> a.select{|e| (a-[e]).size < a.size - 1}.uniq
=> [1, 2]

kind regards -botp