From: Belorion <belorion@...>
Date: 2005-01-27T00:33:54+09:00
Subject: Array::uniq { block } ?

I have an array of arrays.  I want to be able to do a uniq operation
on my array, and have it accept a block so I can specify what to
examine for uniqueness.  For example, in IRB

a = [ [1,2], [3,4], [1,3] ]
a.sort { |x,y| x[0] <=> y[0] }

returns => [ [1,2], [1,3], [3,4] ]

However, it does not appear uniq accepts blocks:

a = [ [1,2], [3,4], [1,3] ]
a.uniq { |x,y| x[0] == y[0] }

returns => [ [1,2], [3,4], [1,3] ]
and a.uniq! with the above block returns nil.  

Am I stuck writing my own deep_uniq?  Granted, it would be hard, but
certainly not as clean as the above.