You can use an underscore (Scala's standard wild card character) as a placeholder to catch any type of exception (really, to match any case in a pattern matching expression).

你可以使用一个下划线(Scala的标准通配符)作为占位符来捕捉任意类型的异常(不骗你，它可以匹配模式匹配表达式的任何case)。

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What about a sparkly border, or using card stock that has a subtle shimmer? Or, use a wax seal on your envelopes in the shape of a feather, bow or the flower pattern on your wedding dress.

考虑给你的婚礼请柬增加一些补充的细节，比如一条金边或是闪光的卡纸，或是用蜂蜡在请柬上盖一个羽毛状的印章，在婚纱上加一些蝴蝶结、花边。

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You may include a "default" case at the end of a pattern match, either using the underscore wild card character or a meaningfully-named variable.

你可以在模式匹配的最后包含一个“default”默认case，可以使用下划线通配符，或者有含义的变量名。

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