magdamiu

var someNumbers = listOf(1, 4, 5, 6, 7, 8, 2323, 5456, 343, 2)
someNumbers
    .filter { it % 2 == 0 } 
    .map { it * 3 } 
    .sum()

someNumbers
    .asSequence()
    .filter { it % 2 == 0 }
    .map { it * 2 }

magdamiu

sealed class Fruit(val name: String) {
    class Apple : Fruit("Apple")
    class Mango : Fruit("Mango")
}

class Pomegranate : Fruit("Pomegranate")

fun display(fruit: Fruit) {
    when (fruit) {
        is Fruit.Apple -> println("${fruit.name} is good for iron")

magdamiu

val displayContentWithTemplate = "Hello $firstName! Please confirm that $email is your email address."

magdamiu

inputStream.use {
    outputStream.use {
        // do something with the streams
        outputStream.write(inputStream.read())
    }
}

// improved option
arrayOf(inputStream, outputStream).use {
   // do something with the streams

magdamiu

interface ValueHolder<V> {
    val value: V
}
class IntHolder : ValueHolder<Int> {
    override val value: Int
        get() = Random().nextInt()
}
fun main() {
    val sample = IntHolder()
    println(sample.value) //260078462

magdamiu

fun main() {
    smallList()
    smallSequence()
}

fun smallList() = (0..5)
    .filter { print("list filter($it) "); it % 2 == 0 }
    .map { print("list map($it) "); it * it }
    .first()

magdamiu

inline fun <reified T> printTypeName() {
    println(T::class.simpleName)
}

fun main() {
    printTypeName<String>() 
    println(String::class.simpleName) 
}

magdamiu

inline fun <T, R : Comparable<R>> Iterable<T>.sortedBy(crossinline selector: (T) -> R?): List<T> {
    return sortedWith(compareBy(selector))
}

magdamiu

inline fun computeValues(
    number: Int, doubleValue: (number: Int) -> Unit,
    noinline tripleValue: (number: Int) -> Unit) {
    
    doubleValue.invoke(number)
    tripleValue.invoke(number)
}

fun main() {
    val number = 7;

magdamiu

var priceBooks = 0.0
val prefixPriceDetails = "The current sum is "
books.forEach {
    priceBooks += it.price
    println("$prefixPriceDetails $priceBooks")
}