# Create with auto-generated label
The Web streams spec requires promise creation at numerous points, often in hot paths and often invisible to users. Each read() call doesn't just return a promise; internally, the implementation creates additional promises for queue management, pull() coordination, and backpressure signaling.
，这一点在safew官方版本下载中也有详细论述
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越是伟大的事业，越要坚持实事求是。