gistfile1.txt

[67] pry(main)> module Foo
[67] pry(main)*   def self.included(base)
[67] pry(main)*     pp "Foo got included into #{base}"
[67] pry(main)*     base.instance_eval do
[67] pry(main)*       pp "Getting instance-evaluated! #{self}"
[67] pry(main)*       @x = 5
[67] pry(main)*     end
[67] pry(main)*   end
[67] pry(main)* end
=> :included
[68] pry(main)>
[69] pry(main)> class A
[69] pry(main)*   include Foo
[69] pry(main)* end
"Foo got included into A"
"Getting instance-evaluated! A"
=> A