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iOS Intermediate Swift 2 Extensions and Protocols Extending a Native Type

Calvin Liem
Calvin Liem
3,599 Points

checking int from given String

how to check an Int from given String and how to return nil from expected return Int

types.swift
// Enter your code below
extension String {
 func add(tambah: Int) -> Int {
    if self == self.toInt() {
        return self + tambah
    } else { return nil }
 }

}

"1".add(2)

2 Answers

Ivan Kazakov
PLUS
Ivan Kazakov
Courses Plus Student 43,317 Points
extension String {

    func add(value: Int) -> Int? {

        guard let intVal = Int(self) else {
            return nil
        }

        return intVal + value
    }
}
Calvin Liem
Calvin Liem
3,599 Points

omg im totally forget about optional thanks