title: How to capture user submitted attribute values when ActiveRecord validation fails?
body: <p>Is there an elegant way to call a method when a <strong>specific</strong> ActiveRecord validation fails?  I'm envisioning something like...</p>
  
  <p>validates :email_address, :uniqueness => true, <strong>:when_fail => :call_method</strong></p>
  
  <p>I have a roundabout way of calling the method when the validation fails involving code in my controller, but I'm looking for something more straight-forward within the model.  I can't find any relevant examples online.</p>
  
  <p>EDITED out other details to focus on the question.</p>