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Swift Protocol-Oriented Programming

You're reading from   Swift Protocol-Oriented Programming Increase productivity and build faster applications with Swift 5

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Product type Paperback
Published in Jun 2019
Publisher
ISBN-13 9781789349023
Length 224 pages
Edition 4th Edition
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Author (1):
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Jon Hoffman Jon Hoffman
Author Profile Icon Jon Hoffman
Jon Hoffman
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Toc

Table of Contents (11) Chapters Close

Preface 1. Starting with the Protocol 2. Our Type Choices FREE CHAPTER 3. Extensions 4. Generics 5. Memory Management 6. Object-Oriented Programming 7. Protocol-Oriented Programming 8. Adopting Design Patterns in Swift 9. Case Studies 10. Other Books You May Enjoy

Unowned references

An unowned reference is a non-strong (or weak) reference to an instance. This means that the reference to the instance is not taken into account by ARC. An unowned reference is always expected to contain a value and should never be nil.

We begin by creating two more classes, MyClass1_Unowned and MyClass2_Unowned:

class MyClass1_Unowned {
var name = ""
unowned let class2: MyClass2_Unowned
init(name: String, class2: MyClass2_Unowned) {
self.name = name
self.class2 = class2
print("Initializing class1_Unowned with name \(self.name)")
}
deinit {
print("Releasing class1_Unowned with name \(self.name)")
}
}
class MyClass2_Unowned {
var name = ""
var class1: MyClass1_Unowned?
init(name: String) {
self.name = name
print("Initializing class2_Unowned with name \...
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