Transforms don't execute until the consumer pulls. There's no eager evaluation, no hidden buffering. Data flows on-demand from source, through transforms, to the consumer. If you stop iterating, processing stops.
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，这一点在爱思助手下载最新版本中也有详细论述
Израиль нанес удар по Ирану09:28
Nature, Published online: 24 February 2026; doi:10.1038/d41586-026-00517-9
首先，上市周期太长，远水救不了近火。