Book Image

Swift 4 Programming Cookbook

Book Image

Swift 4 Programming Cookbook

Overview of this book

Swift 4 is an exciting, multi-platform, general-purpose programming language. Being open source, modern and easy to use has made Swift one of the fastest growing programming languages. If you interested in exploring it, then this book is what you need. The book begins with an introduction to the basic building blocks of Swift 4, its syntax and the functionalities of Swift constructs. Then, introduces you to Apple's Xcode 9 IDE and Swift Playgrounds, which provide an ideal platform to write, execute, and debug the codes thus initiating your development process. Next, you'll learn to bundle variables into tuples, set order to your data with an array, store key-value pairs with dictionaries and you'll learn how to use the property observers. Later, explore the decision-making and control structures in Swift and learn how to handle errors in Swift 4. Then you'll, examine the advanced features of Swift, generics and operators, and then explore the functionalities outside of the standard library, provided by frameworks such as Foundation and UIKit. Also, you'll explore advanced features of Swift Playgrounds. At the end of the book, you'll learn server-side programming aspect of Swift 4 and see how to run Swift on Linux and then investigate Vapor, one of the most popular server-side frameworks for Swift.
Table of Contents (9 chapters)

While loops

For loops are great when you know how many times you intend to loop, but if you want to loop until a certain condition is met, you need a while loop.

A while loop has the following syntax:

while <#boolean expression#> { 
<#code to execute#>

The code block will execute over and over until the Boolean expression returns false. Therefore, it's a common pattern to change the current state in the code block that may cause the Boolean expression to change to false.

If there is no chance that the Boolean expression can become true, the code will loop forever, which can lock up your app.

Getting ready

Let's work out how many times in a row we can flip a coin and get heads.

To flip our coin,...