Since it is implemented as an anonymous function within another function, one could do some preliminary checks and calculations before creating the iterator.

由于它是在另外一个函数当中实现了一个匿名函数，人们就能够做一些前置检查和在迭代器创建之后进行计算。

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A: Sure. Let me check the balance. (Mr. Wang picks up a file and checks the Preliminary Sale and Purchase Agreement.) the balance is forty-three thousand HongKong dollars.

好的，让我先查看差额。(王先生拿出文件，查看临时买卖合约。)差额是四万三千港币。

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The cape quake whose preliminary magnitude is measured at 6.6 is reported to have rattled houses and to have caused the partial closure of a nuclear power station for safety checks.

这场地震最初的震级为6.6，造成房屋多处房屋倒塌。为了进行安全检查，核电站部分关闭。

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