internal fun AtomicRef<MutableList<Pair<KClass<*>, KSerializer<*>>>>.getOrWait(): MutableList<Pair<KClass<*>, KSerializer<*>>> {
    while (this.value == emptyList<MutableList<Pair<KClass<*>, KSerializer<*>>>>())
        suspend {
            delay(10)
        }
    return this.value
}

private val routes = mapOf<Regex, (vararg args: String) -> LaunchAction?>(

vararg

CoroutineScope.launch{ }

val scope = CoroutineScope(Dispatchers.Default)
    println(
        measureTimeMillis {
            scope.launch { }
        }
    )
// 40

val version = service.getAllTemplates()
  .find { ... }
  ?.versions // returns a list
  ?.single()
  ?: error("no template found matching the given predicate")

find{}

single()

singleOrNull()

error(…)

fun removeUsedLetters() {
        val boardLetters = readBoardLetters.value!!.toMutableList()
        val newList = boardLetters.remove(letter.value)
        println("remaining = $newList")
    }

remove()

typealias AABB = Rectangle

fun Rectangle(x: Int = 0, y: Int = 0, width: Int = 0, height = 0) = ...

fun Rectangle.invoke(x: Int ...

val someProperty: SomeClass = 50%

open class Animal(val name: String)
class LandAnimal(name: String, val legs: Int) : Animal(name)
class SeaAnimal(name: String, val flippers: Int) : Animal(name)

fun printAppendages(animal: SeaAnimal) {
    print(" has ${animal.flippers} flippers")
}

fun printAppendages(animal: LandAnimal) {
    print(" has ${animal.legs} legs")
}

fun printAppendages(animal: Animal) {
    print(" has no appendages")
}

fun <T : Animal> printAnimal(animal: T) {
    print(animal.name)
    
    printAppendages(animal)
    
    print("\n")
}

fun main() {
    val lassie = LandAnimal("Lassie", 4)
    val nemo = SeaAnimal("Nemo", 2)
    
    printAnimal(lassie)
    printAnimal(nemo)
}

Lassie has no appendages
Nemo has no appendages

letterList.value

boardLetterList

val difference = boardLetterList.filterNot{ letterList.value!!.contains(it) }

tailrec

tailrec fun Context.activity(): Activity? = when {
  this is Activity -> this
  else -> (this as? ContextWrapper)?.baseContext?.activity()
}

and((MutableCollection<out Condition!>..Collection<Condition!>?))

MutableCollection<out Condition!>

import kotlin.reflect.full.*

class Plant{
    fun trim(){}
    fun fertilize(){}
}

fun testAnnotations(){
    val classObj = Plant::class

    for (m in classObj.declaredMemberFunctions){
        println(m.name)
    }
}

declaredMemberFunctions

class SomeThing {
    fun throwAnException(): Nothing { ... }
}

// ...
val s: SomeThing = ...
if (...) 
    s.throwAnException()

class SomeThing {
    fun anException(): Exception { ... }
}

// ...
val s: SomeThing = ...
if (...) 
    throw s.anException()

fun main() {
    var newList1 = listOf(listOf(1, "a", "b"), listOf(1, "a", "b"), listOf(1, "a", "b"))
    var newList = listOf(1, "b", "C" to newList1)
    var defaultList = listOf(1, "a", 'B' to newList)

    var a = defaultList[2]

	print(a::class.java.typeName)  //kotlin.Pair
}
I need to access "newList1" but i cant since "defaultList" is a Pair
how can i access via index or how can i construct to get this behaviour

kotlinx.collections.immutable

sealed interface

sealed class