# File lib/merb-cache/merb-cache.rb, line 81
  def expire_key_for(options, controller, controller_based = false)
    key = ""
    if options.is_a? Hash
      case
      when key = options[:key]
      when action = options[:action]
        controller = options[:controller] || controller
        key = "/#{controller}/#{action}"
      when match = options[:match]
        key = match
      end
      if _params = options[:params]
        key += "/" + _params.join("/")
      end
      yield key, !options[:match].nil?
    else
      yield controller_based ? "/#{controller}/#{options}" : options, false
    end
  end