Book Image

Rust Essentials - Second Edition

By : Ivo Balbaert
Book Image

Rust Essentials - Second Edition

By: Ivo Balbaert

Overview of this book

Rust is the new, open source, fast, and safe systems programming language for the 21st century, developed at Mozilla Research, and with a steadily growing community. It was created to solve the dilemma between high-level, slow code with minimal control over the system, and low-level, fast code with maximum system control. It is no longer necessary to learn C/C++ to develop resource intensive and low-level systems applications. This book will give you a head start to solve systems programming and application tasks with Rust. We start off with an argumentation of Rust's unique place in today's landscape of programming languages. You'll install Rust and learn how to work with its package manager Cargo. The various concepts are introduced step by step: variables, types, functions, and control structures to lay the groundwork. Then we explore more structured data such as strings, arrays, and enums, and you’ll see how pattern matching works. Throughout all this, we stress the unique ways of reasoning that the Rust compiler uses to produce safe code. Next we look at Rust's specific way of error handling, and the overall importance of traits in Rust code. The pillar of memory safety is treated in depth as we explore the various pointer kinds. Next, you’ll see how macros can simplify code generation, and how to compose bigger projects with modules and crates. Finally, you’ll discover how we can write safe concurrent code in Rust and interface with C programs, get a view of the Rust ecosystem, and explore the use of the standard library.
Table of Contents (13 chapters)

Structs


Often you need to keep several values of possibly different types together in your program, for example, the scores of the players. Let us say that the score contains numbers indicating the health of the players and the level at which they are playing. The first thing you can do to clarify your code is to give these tuples a common name, like:

struct Score; 

Or better still, indicate the types of the values:

struct Score(i32, u8); 

And we can make a score like this:

// from Chapter 4/code/structs.rs 
let score1 = Score(73, 2); 

These are called tuple structs because they resemble tuples very much.The values contained in them can be extracted like this:

let Score(h, l) = score1; // destructure the tuple 
println!("Health {} - Level {}", h, l); 

This prints the following output:

Health 73 - Level 2

A tuple struct with only one field (called a newtype) gives us the possibility to create a new type based on an old one, so that both have the same memory representation. Here is an example:

struct...