LinkedList in Swift

LinkedList.swift

indirect enum LinkedListNode<T> {
    case value(element: T, next: LinkedListNode<T>)
    case end
}

extension LinkedListNode: Sequence {
    func makeIterator() -> LinkedListIterator<T> {
        return LinkedListIterator(self)
    }
}

struct LinkedListIterator<T>: IteratorProtocol {
    var current: LinkedListNode<T>
    
    init(_ current: LinkedListNode<T>) {
        self.current = current
    }
    
    mutating func next() -> T? {
        switch current {
        case .value(let element , let next):
            self.current = next
            return element
        case .end:
            return nil
        }
    }
}

// =============

let list = LinkedListNode.value(element: 10, next: .value(element: 20, next: .value(element: 30, next: .end)))

list.forEach { number in
    print(number)
}