Book Image

Rust Quick Start Guide

By : Daniel Arbuckle
Book Image

Rust Quick Start Guide

By: Daniel Arbuckle

Overview of this book

Rust is an emerging programming language applicable to areas such as embedded programming, network programming, system programming, and web development. This book will take you from the basics of Rust to a point where your code compiles and does what you intend it to do! This book starts with an introduction to Rust and how to get set for programming, including the rustup and cargo tools for managing a Rust installation and development work?ow. Then you'll learn about the fundamentals of structuring a Rust program, such as functions, mutability, data structures, implementing behavior for types, and many more. You will also learn about concepts that Rust handles differently from most other languages. After understanding the Basics of Rust programming, you will learn about the core ideas, such as variable ownership, scope, lifetime, and borrowing. After these key ideas, you will explore making decisions in Rust based on data types by learning about match and if let expressions. After that, you'll work with different data types in Rust, and learn about memory management and smart pointers.
Table of Contents (10 chapters)

Moving and borrowing in pattern matches

When we match a pattern that contains variables, the matching data values are moved into the variables (unless their data type has the Copy trait). For example, this will cause the compiler to report an error, even though at first glance it seems reasonable, especially for people who are used to other programming languages:

let source5 = DemoStruct { id: 40, name: String::from("A Surprising Thing"), probability: 0.93 };

if let DemoStruct {id: 41, name: x, probability: _} = source5 {
println!("Extracted name: {}", x);

println!(" is {}",;

The problem is that, after the if let, does not (or at least might not) contain a value anymore, because that value was moved to the x variable. The compiler can't be sure that the final println! command will always be valid, which...