Mastering Kotlin

Conventions used

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "Demonstrations of null and non-null types."

A block of code is set as follows:

data class Language(val name: String)fun main(args: Array<String>) {  val language = Language("Kotlin")  println(language.name)}

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

fun main(args: Array<String>) {    var language: String = "Kotlin"    language = null // Error: Null can not be a value of a non-null type String}

Any command-line ...