Book Image

Rust Standard Library Cookbook

By : Jan Hohenheim, Daniel Durante
Book Image

Rust Standard Library Cookbook

By: Jan Hohenheim, Daniel Durante

Overview of this book

Mozilla’s Rust is gaining much attention with amazing features and a powerful library. This book will take you through varied recipes to teach you how to leverage the Standard library to implement efficient solutions. The book begins with a brief look at the basic modules of the Standard library and collections. From here, the recipes will cover packages that support file/directory handling and interaction through parsing. You will learn about packages related to advanced data structures, error handling, and networking. You will also learn to work with futures and experimental nightly features. The book also covers the most relevant external crates in Rust. By the end of the book, you will be proficient at using the Rust Standard library.
Table of Contents (12 chapters)

How it works...

This example, adapted with slight changes from the second edition of the Rust book (https://doc.rust-lang.org/book/second-edition/), shows you how to start the implementation of a custom smart pointer. In our case, all it does is print the Debug information of the data stored when its dropped [26]. We do this by implementing the Drop trait with its single drop function [25], which the compiler automatically calls whenever a variable is dropped. All smart pointers are implemented this way.

The moment of a variable drop will nearly always be when it leaves its scope. For this reason, we cannot call the drop function directly[38]. The compiler will still call it when it exits its scope, so the cleanup will happen twice, resulting in undefined behavior. If you need to drop a variable early, you can tell the compiler to do so for you by calling std::mem:drop on it [41].

Variables that exit their scope are dropped in a LIFO way: Last In, First Out. That means that the last variable...