title: Ruby comparing dates
body: <p>I would like to do is to know if a user has been created in the system in the last 10 second.
  so i would  do:</p>
  
  <pre><code>  def new_user
      if(DateTime.now - User.created_at &lt; 10)
        return true
      else 
        return false 
      end
    end
  </code></pre>
  
  <p>IT is just an idea , how can i do it correctly?
  thank you</p>