Instead of checking for a default compound value, you can also catch the access to an undefined variable. E.g.

不用再检查默认的复合值，您也可以捕获对未定义变量的访问。

youdao

In refusing to run to catch trains, I have felt the true value of elegance and aesthetics in behavior, a sense of being in control of my time, my schedule, and my life.

从拒绝追赶列车中，我体会到“优雅”的真正价值和行为中的美学，一种控制我的时间、行程和生活的感觉。

youdao

Pulling high-priority sources out of the full stream and putting them in a special place enables you to catch more of the high-value information those sources publish.

把高优先级的内容源从所有信息流中分离出来，可以让你从这些内容源里获得更多高价值信息。

youdao

Even with less shelf space and low prices, Walmart can still make bank in the volume of transactions as the formats catch on as customers seek value, not volume.

FORBES: Why Walmart Is Betting Big On Small Stores

The value proposition of the cloud is compelling for the first two or three years, then begins to catch up to on-premises IT costs.

FORBES: How Cloud Computing is Fueling the Next Startup Boom

So he describes Grey's visits to Mormon settlements, his identification with the Navajo cause and his fishing expeditions which, to judge from some rather risible photographs, resulted in the occasional enormous catch, though producing little of literary value.

ECONOMIST: The writer of westerns