INSTANCE EVALER!

omg.rb

omg = Class.new do
  attr_accessor :test1
  attr_accessor :test2

  def inspect
    puts "test1", test1.inspect
    puts "test2", test2.inspect
    puts "="*40
  end
end

wow = omg.new
wow.inspect

wow.instance_eval(IO.read("smth.rb"))
wow.inspect

output

test1
nil
test2
nil
========================================
test1
"wow1"
test2
"wow2"
========================================

smth.rb

instance_eval(IO.read("template.rb"))
self.test1 = "wow1"

template.rb

self.test2 = "wow2"