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iOS Generics in Swift Generic Types Creating a Generic Type

Raphael Varquez
Raphael Varquez
4,758 Points

Creating a Generic Type Challenge 4/5

Need help trying to make an instance method that appends a number to the end of the array.

struct Queue<Element>{
  var array: [Element] = []

  var isEmpty: Bool {
        if array.count == 0 {
            return true
        } else {
            return false

  var count: Int {
    let index = array.count
    return index

  func enqueue(_ number: Element) {


1 Answer

2,128 Points

You have to put the keyword mutating in front of your instance method

mutating func enqueue(_ element: Element) {