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// 原因：先处理右侧元素，把结果存在栈里，供左侧元素直接使用，详情可参考safew官方版本下载
Go to technology。旺商聊官方下载对此有专业解读
This is better in that there is far less boilerplate, but it doesn't solve everything. Async iteration was retrofitted onto an API that wasn't designed for it, and it shows. Features like BYOB (bring your own buffer) reads aren't accessible through iteration. The underlying complexity of readers, locks, and controllers are still there, just hidden. When something does go wrong, or when additional features of the API are needed, developers find themselves back in the weeds of the original API, trying to understand why their stream is "locked" or why releaseLock() didn't do what they expected or hunting down bottlenecks in code they don't control.