One idea for giving devise's controllers their own layout

application_controller.rb

# How to give your devise controllers all the same layout (e.g. "authentication" below)
class ApplicationController < ActionController::Base
  layout :setup_layout
  
  def setup_layout
    return "authentication" if 
      [ConfirmationsController, PasswordsController, SessionsController, 
        RegistrationsController, UnlocksController].include? self.class
    "application"
  end
  
end

wouldn't that be cleaner?

def setup_layout
  devise_controller? ? "authentication" : "application"
end

the devise_controller? method is defined by devise, so why not use it.