def tok!
  loop do
    @line = @port.gets if @line == ''

    return EOF_OBJECT if @line.nil?

    m_data = TOKEN_REGEXP.match @line
    token, @line = m_data[1, 2] if m_data

    return token unless token.nil? or token == '' or token[0] == TOKENS[:sl_comment]
  end
end