Iterators

                  val numbers = listOf("one", "two", "three", "four")
val numbersIterator = numbers.iterator()
while (numbersIterator.hasNext()) {
    println(numbersIterator.next())
}
                

                    let numbers = listOf("one", "two", "three", "four")
let numbersIterator = numbers.iterator()
while (numbersIterator.hasNext()) {
    print(numbersIterator.next())
}
                  

                  val numbers = listOf("one", "two", "three", "four")
for (item in numbers) {
    println(item)
}
                

                    let numbers = listOf("one", "two", "three", "four")
for (item in numbers) {
    print(item)
}
                  

                  val numbers = listOf("one", "two", "three", "four")
numbers.forEach {
    println(it)
}
                

                    let numbers = listOf("one", "two", "three", "four")
numbers.forEach {
    print(it)
}
                  

List iterators

                  val numbers = listOf("one", "two", "three", "four")
val listIterator = numbers.listIterator()
while (listIterator.hasNext()) listIterator.next()
println("Iterating backwards:")
while (listIterator.hasPrevious()) {
    print("Index: ${listIterator.previousIndex()}")
    println(", value: ${listIterator.previous()}")
}
                

                    let numbers = listOf("one", "two", "three", "four")
let listIterator = numbers.listIterator()
while (listIterator.hasNext()) listIterator.next()
print("Iterating backwards:")
while (listIterator.hasPrevious()) {
    print("Index: ${listIterator.previousIndex()}")
    print(", value: ${listIterator.previous()}")
}
                  

Mutable iterators

                  val numbers = mutableListOf("one", "two", "three", "four") 
val mutableIterator = numbers.iterator()
​
mutableIterator.next()
mutableIterator.remove()    
println("After removal: $numbers")
                

                    let numbers = mutableListOf("one", "two", "three", "four") 
let mutableIterator = numbers.iterator()
​
mutableIterator.next()
mutableIterator.remove()    
print("After removal: $numbers")
                  

                  val numbers = mutableListOf("one", "four", "four") 
val mutableListIterator = numbers.listIterator()
​
mutableListIterator.next()
mutableListIterator.add("two")
mutableListIterator.next()
mutableListIterator.set("three")   
println(numbers)
                

                    let numbers = mutableListOf("one", "four", "four") 
let mutableListIterator = numbers.listIterator()
​
mutableListIterator.next()
mutableListIterator.add("two")
mutableListIterator.next()
mutableListIterator.set("three")   
print(numbers)