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iOS Intermediate Swift 2 Extensions and Protocols Extending a Native Type

Connor Crawford
Connor Crawford
6,405 Points

Keep getting an error saying "use of unresolved identifier NSNumberFormat()." Any other solution suggestions?

Xcode accepts my solution but workspaces does not. I would also like to try and find a solution that is more flexible than the one I came up with here. The goal is to add an integer to a string if the string contains an integer otherwise return nil. This have to be within an extension of the class String aka no stored properties. Thanks for the help!

types.swift
// Enter your code below
extension String {

    func add(int: Int) -> Int? {
        var myString: String = "1"

        if let myNumber = NSNumberFormatter().numberFromString(myString) {
            var myInt = myNumber.integerValue
            return myInt + int
        } else {
            return nil
        }

      }

}

1 Answer

Connor Crawford
Connor Crawford
6,405 Points

Figured out wayyyyy easier solution.

extension String { func add(intA: Int) -> Int? { if let intB = Int(self) { return intB + intA } else { return nil }

}

}