Sometimes you want to handle errors from a group of operations in one place rather than propagating them up. try-catch catches errors from ? propagation inside the try block:
That's roughly 10x cheaper.
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但它好就好在这是一个高度集成的软硬件结合功能，你可以把它设置成按条件触发，不用像防窥膜那样偶尔撕掉一次还得重新买。