Eliæ

Another reason to avoid instance variables into Rails controllers? /2

They have an insane implementation:

(still in rails head)

# Define some internal variables that should not be propagated to the view.
self.protected_instance_variables = [
  :@_status, :@_headers, :@_params, :@_env, :@_response, :@_request,
  :@_view_runtime, :@_stream, :@_url_options, :@_action_has_layout
]