patrickcousins

sealed class Yarn {
   class Cotton : Yarn()
   class Silk : Yarn()
   sealed class Wool : Yarn() {
       class Merino : Wool()
       class Alpaca : Wool()
   }
}

patrickcousins

val yarn = when(spool) {
   is Yarn.Wool -> knit()
   is Yarn.Cotton -> knit()
}

patrickcousins

class Merino : Yarn.Wool()

patrickcousins

sealed class Yarn() {
   class Cotton : Yarn()
   class Wool : Yarn()
}

patrickcousins

val done = when (result) {
   is Result.Success -> showList(result.items)
   is Result.Failure -> result.error.printStackTrace()
}

patrickcousins

sealed class Result {
 class Success(val items: List<String>): Result()
 class Failure(val error: Throwable): Result()
 class Cancelled(): Result()
}

patrickcousins

when (result) {
  is Result.Success -> showItems(result.items)
  is Result.Failure -> result.error.printStackTrace()
}

patrickcousins

sealed class Result {
 class Success(val items: List<String>): Result()
 class Failure(val error: Throwable): Result()
}

patrickcousins

<?php

class Bottles {

    function verse($num_bottles):string {

        if ($num_bottles == 2) {
            return "2 bottles of beer on the wall, 2 bottles of beer.\nTake one down and pass it around, 1 bottle of beer on the wall.";
        }

patrickcousins

Resources for learning Kotlin

##Main

• Kotlin
• Try Kotlin online: http://try.kotlinlang.org/
• Reference: https://kotlinlang.org/docs/reference/
• Blog: https://blog.jetbrains.com/kotlin/
• Community: https://kotlinlang.org/community.html
• Twitter: https://twitter.com/kotlin