Dunno what I want to show

a.rb

class Post
  after_create do
    Twitter.add_to_stream(self.title)
  end
end

b.rb

class Blog
  def post(post_attributes)
    post = posts.create!(post_attributes)
    Twitter.add_to_stream(post.title)
  end
end

c.rb

class Blog
  def post(post_attributes, twitter_client)
    post = posts.create!(post_attributes)
    twitter_client.add_to_stream(post.title)
  end
end

d.rb

class Blogging
  def initialize(blog, twitter_client)
  end

  def post(post_attributes)
    post = @blog.add_post(post_attributes)
    @twitter_client.add_to_stream(post.title)
  end
end