title: Whenever a User object is created, create UserInfo object too
body: <p>Whenever a <code>User</code> object is created, I want a <code>UserInfo</code> object to be created too, and linked to it.</p>
  
  <p>Unfortunately this does not create any <code>UserInfo</code>:</p>
  
  <pre><code>class User &lt; ActiveRecord::Base
    has_one :user_info
    ...
  
    def init
      self.user_info = user_info
      self.save!
    end
  </code></pre>
  
  <p>Why is the <code>init</code> method not called? How to reach my goal?</p>