Swift Functional Programming - Second Edition

Size

We can implement a computed size property to calculate the size of a linked list as follows:

var size: Int {     switch self {     case .node(_, let next):         return 1 + next.size     case .end:         return 0     } } 

This method recursively goes through LinkedList and counts the number of nodes:

print(functionalLinkedList.size) 

The result is going to be 3 in this example.