From: Jonah Bloch-Johnson <jsb2142@...>
Date: 2008-08-20T08:16:22+09:00
Subject: Nested Arrays in Method Definitions--a puzzle

Hello there Ruby-minded people!

     I am writing because I am somewhat stumped by why the following  
discrepency occurs; having defined the following:

class Warfare
   def haves
	x = [1]
	y = []
	y << x
	x = [2] # (compare this)
	y
   end
   def havenots
	x = [1]
	y = []
	y << x
	x[0] = 2 # (to this)
	y
   end
end

I get this in irb:

>> load 'snah.rb'
=> true
>> a = Warfare.new
=> #<Warfare:0x33a93c>
>> a.haves
=> [[1]]
>> a.havenots
=> [[2]]

Why does meddling with the innards of the "x" have retroactive  
repercussions, whereas redefining it outright does not?

Any insight would be greatly appreciated.

-Jonah