If... (Conditionals)

Use if when you want to ask the computer a question. Kotlin’s style is similar to other languages, but it has a cool bonus.

Ask a question

val score = 85

if (score >= 80) {
    println("You passed!")
}

Translation:

Remember score as 85 (it will not change)

If (score is greater than or equal to 80) {
    print "You passed!"
}

No! (else)

if (score >= 80) {
    println("Pass!")
} else {
    println("Fail...")
}

Ask multiple times (else if)

When questions chain together, you can ask again.

if (score >= 90) {
    println("Excellent")
} else if (score >= 80) {
    println("Good")
} else {
    println("Needs work")
}

Translation:

If (score is 90 or higher) { ... }
Otherwise, if (score is 80 or higher) { ... }
Otherwise { ... }

Kotlin’s secret move: the question box

In Kotlin, you can store the result of an if directly into a variable.

val result = if (score >= 80) "Pass" else "Fail"
println(result)

Translation:

If score is 80 or higher, put "Pass" into result; otherwise put "Fail"

Once you get used to it, your code becomes shorter and cleaner. And remember: the block ends where the braces close.