title: Subscribe to Rails Exceptions, using ActiveSupport::Notifications.subscribe
body: <p>I am exploring ActiveSupport::Notifications, and would like to subscribe to Rails Exceptions, such as the ActiveRecord::ActiveRecordError exception. Something like:</p>
  
  <pre><code>ActiveSupport::Notifications.subscribe /ActiveRecordError/ do |*args|
  
    # More code here ...
  
  end
  </code></pre>
  
  <p>This subscription would exist in a 3rd party gem, so I don't have the flexibility to wrap my AcitveRecord calls with an "in app" begin/rescue/end. An underlying question, is are Exceptions considered and/or handled as events, that can be subscribed to?</p>