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)

Using don't care in patterns

Sometimes, the trick that variable's names have of matching any value in a pattern would be useful, but we don't actually need the information that would be stored in the variable. For example, we might not care about the error value when matching Result, just the fact that there was an error. In that situation, we can use an _ symbol to indicate I don't care what this value is:

match might_fail(39) {
Ok(x) => { println!("Odd succeeded, name is {}", }
Err(_) => { println!("Odd failed! Woe is me.") }

That's the reason why _ by itself can not be used as a variable name: it has a special meaning of its own. We can match _ against any data value of any data type, even multiple times in the same expression, and the matched values will simply be ignored.

Matching a value to _ does not even...