Search icon CANCEL
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
Android Development with Kotlin

You're reading from   Android Development with Kotlin Enhance your skills for Android development using Kotlin

Arrow left icon
Product type Paperback
Published in Aug 2017
Publisher Packt
ISBN-13 9781787123687
Length 440 pages
Edition 1st Edition
Languages
Tools
Arrow right icon
Authors (2):
Arrow left icon
Marcin Moskala Marcin Moskala
Author Profile Icon Marcin Moskala
Marcin Moskala
Igor Wojda Igor Wojda
Author Profile Icon Igor Wojda
Igor Wojda
Arrow right icon
View More author details
Toc

Table of Contents (10) Chapters Close

Preface 1. Beginning Your Kotlin Adventure FREE CHAPTER 2. Laying a Foundation 3. Playing with Functions 4. Classes and Objects 5. Functions as First-Class Citizens 6. Generics Are Your Friends 7. Extension Functions and Properties 8. Delegates 9. Making Your Marvel Gallery Application

Function types


Kotlin supports functional programming, and functions are first-class citizens in Kotlin. A first-class citizen in a given programming language is a term that describes an entity that supports all the operations generally available to other entities. These operations typically include being passed as an argument, returned from a function, and assigned to a variable. The sentence a function is a first-class citizen in Kotlin should then be understood as: it is possible in Kotlin to pass functions as an argument, return them from functions, and assign them to variables. While Kotlin is a statically typed language, there needs to be a function type defined to allow these operations. In Kotlin, the notation used to define a function type is the following:

    (types of parameters)->return type 

Here are some examples:

  • (Int)->Int: A function that takes Int as an argument and returns Int
  • ()->Int: A function that takes no arguments and returns Int
  • (Int)->Unit: A function that...
lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at €18.99/month. Cancel anytime