try, like if and when, can be used as an expression. Whatever is returned by the try block or the executed catch block becomes the value returned by the expression.

So, in this case, since we are trying to get the length of a null String, we fall into the catch block and our expression evaluates to -1.

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Custom Exception Classes Exceptions Exceptions and the Call Stack Jobs Cancel When They Crash Multiple catch Blocks Parent Jobs Cancel When a Child Crashes Throwing Exceptions try and catch try as an Expression
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