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

Macros in Rust and their types


Rust macros do their magic of code generation before the program compiles to a binary object file. They take input, known as token trees, and are expanded at the end of the second pass of parsing during Abstract Syntax Tree (AST) construction. These are pieces of jargon from the compiler world and need some explanation, so let's do that. To understand how macros work, we need to be familiar with how source code is processed by the compiler to understand a program. This will help us in understanding how a macro processes its input and the error messages they emit when we use them incorrectly. We'll only cover parts that are relevant to our understanding of macros.

First, the compiler reads the source code byte by byte and groups characters into meaningful chunks, which are called tokens. This is done by a component of the compiler that's generally referred to as the tokenizer. Therefore, an a + 3 * 6 expression gets converted to "a", "+", "3", "*", "6", which...