gistfile1.txt

class Foo
  attr_accessor :x, :y, :z

  def initialize(x,y,z)
    self.x = x
    self.y = y
    self.z = z
  end
end

class Bar
  attr_accessor :a, :b, :c
  def initialize(a,b,c)
    self.a = a
    self.b = b
    self.c = c
  end
end

module FooComparitor
  def eql?(other)
    # self.hash == other.hash
    if other.kind_of?(Bar)
      other.a == self.x && other.b == self.y
    else
      super
    end
  end

  def hash
    [self.x, self.y].hash
  end
end

module BarComparitor
  def eql?(other)
    # self.hash == other.hash
    puts "Comparign #{self} to #{other}"
    if other.kind_of?(Foo)
      self.a == other.x && self.b == other.y
    else
      super
    end
  end

  def hash
    [self.a, self.b].hash
  end
end


foos = [Foo.new(1,2,3),Foo.new(4,5,6),Foo.new(9,9,9)]
bars = [Bar.new(1,2,3),Bar.new(4,5,6),Bar.new(1,1,1)]

foos.each { |foo| foo.extend(FooComparitor) }
bars.each { |bar| bar.extend(BarComparitor) }

puts (foos - bars).inspect