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.

Preface

What this book covers

What you need for this book

Who this book is for

Reader feedback

Customer support

Free Chapter

Swift Building Blocks

Swift Building Blocks

Your first Swift program

Strings, Ints, Floats, and Bools

Optionals, unwrap, and force unwrap

Building on the Building Blocks

Building on the Building Blocks

Bundling variables into tuples

Ordering your data with arrays

Containing your data with sets

Storing key-value pairs with Dictionaries

Subscripts for custom types

Changing your name with typealias

Getting property changing notifications using property observers

Controlling access with access control

Extending functionality with extensions

Data Wrangling with Swift Control Flow

Data Wrangling with Swift Control Flow

Making decisions with if/else

For the love of loops

Try, throw, do and, catch - Swift error handling

Checking up front with guard

Doing it later with defer

Bailing out with fatalError and precondition

Generics, Operators, and Nested Types

Generics, Operators, and Nested Types

Using generics with types

Using generics with functions

Using generics with protocols

Advanced operators

Create custom operators

Beyond the Standard Library

Beyond the Standard Library

Swift Playgrounds

Swift Playgrounds

Using Swift Playgrounds for UI

Import Resources into Playgrounds

Import Code into Playgrounds

Multi-Page Playgrounds

Server-Side Swift

Server-Side Swift

Swift on Ubuntu

Building a REST API using Vapor

Persistence with Vapor using Postgres

Hosting your Vapor app on Heroku

Performance and Responsiveness in Swift

Performance and Responsiveness in Swift

Value and reference semantics

Dispatch Queues

Concurrent queues and dispatch groups

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For the love of loops

For loops allow you to execute code for each element in a collection or range.

How to do it...

Take a look at the following steps and code:

Let's imagine that we have an array of elements, and we want to do something with every item in the array:

let theBeatles = ["John", "Paul", "George", "Ringo"]

We can use a for loop, which will extract each element of the array in turn, and will execute the given block of code for each element. The syntax of a for loop is as follows:

for <#each element#> in <#collection or range#> { 
    <#code to execute#> 
}

So, to print all the musicians in the Beatles, let's loop through our theBeatles array...