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
Mastering Swift 5

You're reading from   Mastering Swift 5 Deep dive into the latest edition of the Swift programming language

Arrow left icon
Product type Paperback
Published in Apr 2019
Publisher Packt
ISBN-13 9781789139860
Length 370 pages
Edition 5th Edition
Languages
Tools
Arrow right icon
Author (1):
Arrow left icon
Jon Hoffman Jon Hoffman
Author Profile Icon Jon Hoffman
Jon Hoffman
Arrow right icon
View More author details
Toc

Table of Contents (20) Chapters Close

Preface 1. Taking the First Steps with Swift FREE CHAPTER 2. Learning about Variables, Constants, Strings, and Operators 3. Optional Types 4. Using Swift Collections 5. Control Flow 6. Functions 7. Classes, Structures, and Protocols 8. Using Protocols and Protocol Extensions 9. Protocol Oriented Design 10. Generics 11. Availability and Error Handling 12. Custom Subscripting 13. Working with Closures 14. Concurrency and Parallelism in Swift 15. Custom Types 16. Memory Management 17. Swift Formatting and Style Guider 18. Adopting Design Patterns in Swift 19. Other Books You May Enjoy

Strong reference cycles

A strong reference cycle is where the instances of two classes holds a strong reference to each other, preventing ARC from releasing either instance. Once again, we are not able to use a playground for this example, so we need to create an Xcode project. In this project, we start off by creating two classes named MyClass1_Strong and MyClass2_Strong with the following code:

class MyClass1_Strong {  
    var name = "" 
    var class2: MyClass2_Strong?  
    init(name: String) { 
        self.name = name 
        print("Initializing class1_Strong with name \(self.name)") 
    } 
    deinit { 
        print("Releasing class1_Strong with name \(self.name)") 
    } 
} 
 
class MyClass2_Strong {  
    var name = "" 
    var class1: MyClass1_Strong?  
    init(name: String) { 
        self.name = name 
        print(&quot...
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