# File lib/webrobots/robotstxt.rb, line 596
    def allow?(request_uri, user_agent = nil)
      record = find_record(user_agent) or return true
      allow = record.allow?(request_uri)
      if @last_checked and delay = record.delay
        delay -= Time.now - @last_checked
        sleep delay if delay > 0
      end
      @last_checked = Time.now
      return allow
    end