Kotlin Tour

Control structures

If

https://kotlinlang.org/docs/reference/control-flow.html#if-expression

The classic if is revised, it is an expression :

When

https://kotlinlang.org/docs/reference/control-flow.html#when-expression

Kotlin doesn't have a switch keyword, it replaces it with a powerful when expression, similar to pattern matching :

For

https://kotlinlang.org/docs/reference/control-flow.html#for-loops

For loops are implemented as foreach loops, using in keyword :

Ranges

https://kotlinlang.org/docs/reference/ranges.html

Using rangeTo functions ranges can be defined for any comparable type. The .. operator is used to define ranges, in and !in to check if a value is included in a range or to iterate over a range (for integral type). downTo, step and until can be used to revert the range, change the progression step or exclude the last value.