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iOS Error Handling in Swift Error Handling Cleaning Up With Defer

3 Answers

Matt Skelton
Matt Skelton
4,548 Points

That's a really good spot in my opinion. To my understanding, the guard statement you're referring to should be preceded with the throw keyword.

For reference for anybody interested:

func process(file name: String) throws {
    guard isValidFile(withName: name) else {
        throw ReadError.invalidFile    // <--- throw keyword present
    }

    let file = open(fileName: name)

    guard let line = try file.readLine() else {
        ReadError.unableToReadLine     // <--- throw keyword missing
    }
}

Good vision!

hannah echo
hannah echo
2,872 Points

throw isn't required here because of the use of the try keyword

Olivier Van hamme
Olivier Van hamme
5,418 Points

I agree. It must be a typo. At 2:02 Pasan is talking about the second throw statement. He literary mentions it:

From the video transcript:

" … Or in the case of the second throw statement, when we immediately hid that … "

Copy pasting this from the transcript, I discovered another typo: hid instead of hit ?