圖像來源，BBC News Chinese
纳税人以委托方式出口货物的，应当按照国务院税务主管部门的规定办理委托代理出口手续，由委托方按规定申报办理出口退（免）税、免征增值税或者缴纳增值税；未办理委托代理出口手续的，由出口货物的发货人按规定申报缴纳增值税。
，更多细节参见heLLoword翻译官方下载
if (chunks === null) {
You might assume this pattern is inherent to streaming. It isn't. The reader acquisition, the lock management, and the { value, done } protocol are all just design choices, not requirements. They are artifacts of how and when the Web streams spec was written. Async iteration exists precisely to handle sequences that arrive over time, but async iteration did not yet exist when the streams specification was written. The complexity here is pure API overhead, not fundamental necessity.