Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
Save more on your purchases now! discount-offer-chevron-icon
Savings automatically calculated. No voucher code required.
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
Swift 4 Protocol-Oriented Programming

You're reading from   Swift 4 Protocol-Oriented Programming Bring predictability, performance, and productivity to your Swift applications

Arrow left icon
Product type Paperback
Published in Oct 2017
Publisher Packt
ISBN-13 9781788470032
Length 210 pages
Edition 3rd 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 (9) Chapters Close

Preface 1. Starting with the Protocol FREE CHAPTER 2. Our Type Choices 3. Extensions 4. Generics 5. Object-Oriented Programming 6. Protocol-Oriented Programming 7. Adopting Design Patterns in Swift 8. Case Studies

Generic functions

To fully understand generics, we need to understand the problem that they are designed to solve. Let's say that we wanted to create functions that swapped the values of two variables (as described in the first part of this chapter) however, for our application, we have a need to swap the instances of two Integer types, two Double types, and two String types. Without generics, this would require us to write the following three functions:

func swapInts (a: inout Int,b: inout Int) {  
  let tmp = a 
  a = b 
  b = tmp 
} 
 
func swapDoubles(a: inout Double,b: inout Double) {  
  let tmp = a 
  a = b 
  b = tmp 
} 
 
func swapStrings(a: inout String, b: inout String) { 
  let tmp = a 
  a = b 
  b = tmp 
} 

With these three functions, we can swap the instances of two Integer types, two Double types, and two String types. Now, let's say as we develop our...

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 $19.99/month. Cancel anytime