🚙 · Loops

Read on to take quick look at looping in Kotlin, specifically for, while and do-while.

for

The for statement in Kotlin works the same way as the enhanced for statement in Java.

//sampleStart
fun main(args: Array) {
    val cakes = listOf("carrot", "cheese", "chocolate")
    
    for (cake in cakes) { // 1.
        println("Yummy, it's a $cake cake!") // 2.
    }
}
//sampleEnd

1. Loops through each cake in the list.
2. We’ll get to string templates (i.e. the $cake part) in a bit

You might be wondering how to emulate the classic for loop, e.g. for(int i = 0; i < 10; i++). This can be achieved using the above form in combination with ranges, which we’ll talk about soon.

while and do-while

The while and do-while statements work similarly to most languages as well.

//sampleStart
fun eatACake() = println("Eating a Cake!")
fun bakeACake() = println("Baking a Cake!")

fun main(args: Array) {
    var cakesEaten = 0
    var cakesBaked = 0
    
    while (cakesEaten < 5) { // 1.
        eatACake()
        cakesEaten++
    }
    
    do { // 2.
        bakeACake()
        cakesBaked++
    } while (cakesBaked < cakesEaten)

}
//sampleEnd

1. Executes the block while the condition is true.
2. Executes the block first and then checks the condition.

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