Stream.pull() creates a lazy pipeline. The compress and encrypt transforms don't run until you start iterating output. Each iteration pulls data through the pipeline on demand.
Pakistan now in 'open war' with Afghanistan, defence minister says, after countries trade attacks，这一点在51吃瓜中也有详细论述
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A quadtree reduces this: rebuild the tree each frame, and for each object, query only the nearby region. Objects in distant quadrants are never compared.
Fighting False Positives，这一点在safew官方版本下载中也有详细论述