class ActionView::LookupContext

def self.register_detail(name, &block)
  self.registered_details << name
  initialize = registered_details.map { |n| "@details[:#{n}] = details[:#{n}] || default_#{n}" }
  Accessors.send :define_method, :"default_#{name}", &block
  Accessors.module_eval <<-METHOD, __FILE__, __LINE__ + 1
    def #{name}
      @details.fetch(:#{name}, [])
    end
    def #{name}=(value)
      value = value.present? ? Array(value) : default_#{name}
      _set_detail(:#{name}, value) if value != @details[:#{name}]
    end
    remove_possible_method :initialize_details
    def initialize_details(details)
      #{initialize.join("\n")}
    end
  METHOD
end