CircularQueueIterator.swift

import Cocoa


struct CircularQueueIterator<T>: IteratorProtocol {
    let queue: [T]
    private var position = 0
    
    init(queue: [T]) {
        self.queue = queue
    }
    
    mutating func next() -> T? {
        let item = queue[position]
        self.position = ((position + 1) % queue.count)
        return item
    }
}


var arrFruits : CircularQueueIterator<String> = CircularQueueIterator<String>(queue:["Apple", "Orange", "Banana"])
print(arrColor.next())
print(arrColor.next())
print(arrColor.next())
print(arrColor.next())