Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
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

You're reading from   Mastering Swift

Arrow left icon
Product type Paperback
Published in Jun 2015
Publisher Packt
ISBN-13 9781784392154
Length 358 pages
Edition 1st 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 (17) Chapters Close

Preface 1. Taking the First Steps with Swift FREE CHAPTER 2. Learning about Variables, Constants, Strings, and Operators 3. Using Collections and Cocoa Data Types 4. Control Flow and Functions 5. Classes and Structures 6. Working with XML and JSON Data 7. Custom Subscripting 8. Using Optional Type and Optional Chaining 9. Working with Generics 10. Working with Closures 11. Using Mix and Match 12. Concurrency and Parallelism in Swift 13. Swift Formatting and Style Guide 14. Network Development with Swift 15. Adopting Design Patterns in Swift Index

Generic functions


Let's begin by examining the problem that generics try to solve, and then we will see how generics solve this problem. Let's say that we wanted to create functions that swapped the values of two variables (as described in the introduction); however, for our application, we have a need to swap two ints, two doubles, and two strings. Without generics, this would require us to write three separate functions. The following code shows what these functions would look like:

func swapInts (inout a: Int, inout b: Int) {
    let tmp = a
    a = b
    b = tmp
}

func swapDoubles(inout a: Double, inout b: Double) {
    let tmp = a
    a = b
    b = tmp
}

func swapStrings(inout a: String, inout b: String) {
    let tmp = a
    a = b
    b = tmp
}

With these three functions, we can swap the original values of two ints, two doubles, and two strings. Now, let's say, as we develop our application further, we find out that we also need to swap the values of two UInt32, two floats, or even...

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
Banner background image