Android Development with Kotlin

Loops

A loop is a control structure that repeats the same set of instructions until a termination condition is met. In Kotlin, loops can iterate through anything that provides an iterator. An iterator is an interface that has two methods: hasNext and next. It knows how to iterate over a collection, range, string, or any entity that can be represented as a sequence of elements.

To iterate through something, we have to supply an iterator() method. As String doesn't have one, in Kotlin it is defined as an extension function. Extensions will be covered in Chapter 7, Extension Functions and Properties.

Kotlin provides three kinds of loops for, while, and do... while. All of them work the same as in other programming languages, so we will discuss ...