def error(message, url, line, column, key)
      @procs[:html_parser].each { |handler| handler.call(message, url, line, column, key) }
    end
def error(message, url, line, column, key)
      @procs[:html_parser].each { |handler| handler.call(message, url, line, column, key) }
    end
interface HTMLParserListener