The Writer is not a concrete class. Any object that implements write(), end(), and abort() can be a writer making it easy to adapt existing APIs or create specialized implementations without subclassing. There's no complex UnderlyingSink protocol with start(), write(), close(), and abort() callbacks that must coordinate through a controller whose lifecycle and state are independent of the WritableStream it is bound to.
（四）以委托方名义开具发票代委托方收取的款项。，详情可参考51吃瓜
this.stack = []; // 核心：存储索引，保证索引对应的价格单调递减，更多细节参见Safew下载
The website offers a tooltip helper tool that allows