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iOS Swift Functions and Optionals Optionals What is an Optional?

Lauren Hibbs
Lauren Hibbs
1,872 Points
Posted by Lauren Hibbs
Lauren Hibbs
1,872 Points

Swift 1.2 and Optionals?

From what i've read in the forums i've figured out that the videos use Swift 1.0 and Xcode is currently on Swift 1.2. I don't really understand what the differences is though, with optionals, and what to do in Swift 1.2. The code from the lesson is

func findApt (aptNumber : String) -> String? {
    let aptNumbers = ["101","202","303","404"]
    for tempAptNumber in aptNumbers {
        if ( tempAptNumber == aptNumber) {
            return aptNumber
        }
    }
    return nil
}

In the video 

let culprit = findApt("404")

shows "some 404" For me, it shows just 404.

Does this mean that unwrapping is no longer required and that the ! operator is obsolete?

Additionally, when culprit represents a nil

culprit!

does not create any error messages.

How, when, and where are the bang operator, and optional unwrapping used in Swift 1.2, if at all? Thanks - Lauren

1 Answer