In Javascript, is it expensive to use try-catch blocks even if an exception is never thrown?-JavaScript中文网-JavaScript教程资源分享门户

Communitycprcrack提出了一个问题：In Javascript, is it expensive to use try-catch blocks even if an exception is never thrown?，或许与您遇到的问题类似。

回答者K48Esailija给出了该问题的处理方式：

Are you doing typical CRUD UI code? Use try catches, use loops that go to 10000 for no reason sprinkled in your code, hell, use angular/ember - you will not notice any performance issue.

If you are doing low level library, physics simulations, games, server-side etc then the never throwing try-catch block wouldn't normally matter at all but the problem is that V8 didn't support it in their optimizing compiler until version 6 of the engine, so the entire containing function that syntactically contains a try catch will not be optimized. You can easily work around this though, by creating a helper function like tryCatch:

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After V8 version 6 (shipped with Node 8.3 and latest Chrome), the performance of code inside try-catch is the same as that of normal code.

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