title: Can't get ErrorResponse to work on Django Rest Framework
body: <p>This works:</p>
  
  <pre><code>class Right(ResponseMixin, View):
      """Right"""
      renderers = (JSONRenderer, XMLRenderer)
  
      def get(self, request, right_id):
          if not right_id:
              return self.render(
                  Response(status.HTTP_400_BAD_REQUEST,
                           {"successful": False})
              )
  </code></pre>
  
  <p>This doesn't:</p>
  
  <pre><code>class Right(ResponseMixin, View):
      """Right"""
      renderers = (JSONRenderer, XMLRenderer)
  
      # @default_json
      def get(self, request, right_id):
          if not right_id:
              raise ErrorResponse(status.HTTP_400_BAD_REQUEST,
                                  {"successful": False})
  </code></pre>
  
  <p>I get an error message which says:</p>
  
  <p>ErrorResponse at /v1/right/
  No exception supplied</p>
  
  <p>Or: </p>
  
  <pre><code>Environment:
  Request Method: GET
  Request URL: http://127.0.0.1:8000/v1/right/
  
  Django Version: 1.4.1
  Python Version: 2.7.2
  Installed Applications:
  ('django.contrib.auth',
   'django.contrib.contenttypes',
   'django.contrib.sessions',
   'django.contrib.sites',
   'django.contrib.messages',
   'django.contrib.staticfiles')
  Installed Middleware:
  ('api.disable.DisableCSRF',
   'django.middleware.common.CommonMiddleware',
   'django.contrib.sessions.middleware.SessionMiddleware',
   'django.middleware.csrf.CsrfViewMiddleware',
   'django.contrib.auth.middleware.AuthenticationMiddleware',
   'django.contrib.messages.middleware.MessageMiddleware')
  
  
  Traceback:
  File "/Users/agoodattitude/Envs/locker-proxy/lib/python2.7/site-packages/django/core/handlers/base.py" in get_response
    111.                         response = callback(request, *callback_args, **callback_kwargs)
  File "/Users/agoodattitude/Envs/locker-proxy/lib/python2.7/site-packages/django/views/generic/base.py" in view
    48.             return self.dispatch(request, *args, **kwargs)
  File "/Users/agoodattitude/Envs/locker-proxy/lib/python2.7/site-packages/django/views/generic/base.py" in dispatch
    69.         return handler(request, *args, **kwargs)
  File "/Users/agoodattitude/saff-py/locker-proxy/locker_proxy/api/resources.py" in get
    125.                                                          error_message="right_id was not passed."))
  
  Exception Type: ErrorResponse at /v1/right/
  Exception Value: 
  </code></pre>
  
  <p>Does anybody have any idea what "No Exception supplied" means?</p>
  
  <p>(Note, I changed the code very slightly to reduce complexity but the question holds...)</p>