ios - Catch "IndexOutOfBoundsException" in Swift 2

Question

I got this code in my Playground:

func throwsError() throws{
    var x = [1,2]
    print(x[3])
}

func start(){

    do{
        try throwsError()

    }
    catch let unknown{
        "unknown: (unknown)"
    }
}

start()

So obviously the'throwsError function throws an error:

Execution was interrupted, reason: EXC_BAD_INSTRUCTION

Is there a way to catch this? I read online to write a subscript for the Array class that always checks for range but the issue is bigger: Am I not capable to just catch anything?

Answer 1

In Swift, you can't catch anything. You can only catch errors thrown with the throw statement in other Swift code or errors, of type NSError set by called Objective C code.

The default array subscript raises an exception, but does not throw a Swift error, so you cannot use try/catch with it.

See also this article by Erica Sadun.