Meta module madness

gistfile1.rb

module Foo
  def bar
    @bar ||= self.snakes
  end

  def bar=(val)
    @bar = val
  end
end


class Baz
  def self.snakes
    [:cobra]
  end
  extend Foo
end

class Boom < Baz
  @bar = [:copperhead]
end

class Bam < Baz
  def self.snakes
    [:mamba]
  end
end


Baz.bar  # [:cobra]                                                                                                                                                                                       
Boom.bar # [:copperhead]                                                                                                                                                                                  
Bam.bar  # [:mamba]