As progression is Iterable type it can be used in for-loop and function such as filter, map etc. Progression refers to subtype of Iterable, where N is Char, Int or Long. The first element is first, sub-sequent elements represent previous element plus step and the last element is the last element unless progression is completed. Progressions represent the first element, the last element and the step which is non-zero. This is done by using in or !in operators.Īn arithmetic progression is represented by integral type progressions such as CharProgression, IntProgression, Long Progression. The operation performed in range is to check whether the element is contained in it or not. It contains two endpoints as start and end (endInclusive)points. It represents a closed mathematical interval defined for comparable types. Println('This developer with number $i rocks: $')įor ((index, value) in names.Ranges implement ClosedRange a common interface in the library. The in keyword can also be used to check if a value is in a given range!Īnd if you need an index inside your loop, Kotlin allows you to do this in several ways:

This syntax can be found in many recent languages, like Swift, for example… The for loop is now used in the form of in. ('This developer rocks: ' + name) Įn Kotlin, celle-ci est d’ailleurs devenue beaucoup plus lisible : val names = listOf('Jake Wharton', 'Joe Birch', 'Robert Martin') Anyone? Well, that’s to be expected! We have all used this type of loop at least once: List names = Arrays.asList('Jake Wharton', 'Joe Birch', 'Robert Martin') For Once…Īnyone who has never used the for loop in Java, please stand up. Since Kotlin doesn’t bring any special improvement to this way of looping, we’ll skip it. In Kotlin, we have exactly the same thing: // While You probably know the while loop in Java, used to go through a list as long as the condition remains unmet. So this chapter shouldn’t confuse you too much! As Far As Possible If there’s something that hasn’t really changed in Kotlin, it’s the way we loop.

Kotlin loop range