Book Image

The Complete Rust Programming Reference Guide

By : Rahul Sharma, Vesa Kaihlavirta, Claus Matzinger
Book Image

The Complete Rust Programming Reference Guide

By: Rahul Sharma, Vesa Kaihlavirta, Claus Matzinger

Overview of this book

Rust is a powerful language with a rare combination of safety, speed, and zero-cost abstractions. This Learning Path is filled with clear and simple explanations of its features along with real-world examples, demonstrating how you can build robust, scalable, and reliable programs. You’ll get started with an introduction to Rust data structures, algorithms, and essential language constructs. Next, you will understand how to store data using linked lists, arrays, stacks, and queues. You’ll also learn to implement sorting and searching algorithms, such as Brute Force algorithms, Greedy algorithms, Dynamic Programming, and Backtracking. As you progress, you’ll pick up on using Rust for systems programming, network programming, and the web. You’ll then move on to discover a variety of techniques, right from writing memory-safe code, to building idiomatic Rust libraries, and even advanced macros. By the end of this Learning Path, you’ll be able to implement Rust for enterprise projects, writing better tests and documentation, designing for performance, and creating idiomatic Rust code. This Learning Path includes content from the following Packt products: • Mastering Rust - Second Edition by Rahul Sharma and Vesa Kaihlavirta • Hands-On Data Structures and Algorithms with Rust by Claus Matzinger
Table of Contents (29 chapters)
Title Page
Copyright
About Packt
Contributors
Preface
Index

Macro use case – writing tests


Macros are used quite a lot when writing test cases for unit tests. Let's say you were writing a HTTP client library and you would like to test your client on various HTTP verbs such as GET or POST and on a variety of different URLs. The usual way you would write your tests is to create functions for each type of request and the URL. However, there's a better way to do this. Using macros, you can cut down your testing time by many folds by building a small DSL to perform the tests, which is readable and can also be type checked at compiled time. To demonstrate this, let's create a new crate by running cargo new http_tester --lib, which contains our macro definition. This macro implements a small language that's designed for describing simple HTTP GET/POST tests to a URL. Here's a sample of what the language looks like:

http://duckduckgo.com GET => 200
http://httpbin.org/post POST => 200, "key" => "value"

 

The first line makes a GET request to duckduckgo...