Lambdas and Higher-Order Functions

Map and Filter

Use small lambdas to transform and select collection values.

Map and Filter

MapFilter.kt 
fun main() {
    val bonus = 
    val numbers = listOf(1, 2, 3)
    val boosted = numbers.map { value ->
        value + bonus
    }
    val selected = boosted.filter { value ->
        value >= 3
    }
    val summary = selected.joinToString("-")

    println("bonus=$bonus")
    println("summary=$summary")
}

fun main() {
    val bonus = 
    val numbers = listOf(1, 2, 3)
    val boosted = numbers.map { value ->
        value + bonus
    }
    val selected = boosted.filter { value ->
        value >= 3
    }
    val summary = selected.joinToString("-")

    println("bonus=$bonus")
    println("summary=$summary")
}

fun main() {
    val bonus = 
    val numbers = listOf(1, 2, 3)
    val boosted = numbers.map { value ->
        value + bonus
    }
    val selected = boosted.filter { value ->
        value >= 3
    }
    val summary = selected.joinToString("-")

    println("bonus=$bonus")
    println("summary=$summary")
}
map-filter `map` transforms each item, while `filter` keeps only items that match a condition.