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...

In this example, the user can enter any number of key-value pairs until they decide to stop, at which point they receive their input back in the form of JSON. Some example input you could enter could include:

name abraham
age 49
fav_colour red
hello world
(press 'Ctrl Z' on Windows or 'Ctrl D' on Unix)
Use #[cfg(target_os = "some_operating_system")] to handle operating system specific circumstances. In this recipe, we use this to conditionally compile the END_OF_TRANSMISSION constant differently on Windows than on Unix. This key combination tells the OS to stop the current input stream.

This program begins with the idea that a JSON object without a clearly defined schema is nothing but a HashMap<String, String>[9]. Now, serde_json doesn't accept a String as a value, as that would not be general enough. Instead, it wants a serde_json::Value, which you can easily construct by calling the json! macro on pretty much any type [20].