Book Image

Mastering Rust - Second Edition

By : Rahul Sharma, Vesa Kaihlavirta
Book Image

Mastering Rust - Second Edition

By: Rahul Sharma, Vesa Kaihlavirta

Overview of this book

Rust is an empowering language that provides a rare combination of safety, speed, and zero-cost abstractions. Mastering Rust – Second Edition is filled with clear and simple explanations of the language features along with real-world examples, showing you how you can build robust, scalable, and reliable programs. This second edition of the book improves upon the previous one and touches on all aspects that make Rust a great language. We have included the features from latest Rust 2018 edition such as the new module system, the smarter compiler, helpful error messages, and the stable procedural macros. You’ll learn how Rust can be used for systems programming, network programming, and even on the web. You’ll also learn techniques such as writing memory-safe code, building idiomatic Rust libraries, writing efficient asynchronous networking code, and advanced macros. The book contains a mix of theory and hands-on tasks so you acquire the skills as well as the knowledge, and it also provides exercises to hammer the concepts in. After reading this book, you will be able to implement Rust for your enterprise projects, write better tests and documentation, design for performance, and write idiomatic Rust code.
Table of Contents (19 chapters)

Consts in structs, enums, and traits

Structs, enums, and traits definitions can also be provided with constant field members. They can be used in cases where you need to share a constant among them. Take, for example, a scenario where we have a Circle trait that's is meant to be implemented by different circular shape types. We can add a PI constant to the Circle trait, which can be shared by any type that has an area property and relies on value of PI for calculating the area:


trait Circular {
const PI: f64 = 3.14;
fn area(&self) -> f64;

struct Circle {
rad: f64

impl Circular for Circle {
fn area(&self) -> f64 {
Circle::PI * self.rad * self.rad

fn main() {
let c_one = Circle { rad: 4.2 };
let c_two = Circle { rad: 75.2 };
println!("Area of circle one: {}", c_one.area());