Book Image

Mastering Go - Second Edition

By : Mihalis Tsoukalos
Book Image

Mastering Go - Second Edition

By: Mihalis Tsoukalos

Overview of this book

Often referred to (incorrectly) as Golang, Go is the high-performance systems language of the future. Mastering Go, Second Edition helps you become a productive expert Go programmer, building and improving on the groundbreaking first edition. Mastering Go, Second Edition shows how to put Go to work on real production systems. For programmers who already know the Go language basics, this book provides examples, patterns, and clear explanations to help you deeply understand Go’s capabilities and apply them in your programming work. The book covers the nuances of Go, with in-depth guides on types and structures, packages, concurrency, network programming, compiler design, optimization, and more. Each chapter ends with exercises and resources to fully embed your new knowledge. This second edition includes a completely new chapter on machine learning in Go, guiding you from the foundation statistics techniques through simple regression and clustering to classification, neural networks, and anomaly detection. Other chapters are expanded to cover using Go with Docker and Kubernetes, Git, WebAssembly, JSON, and more. If you take the Go programming language seriously, the second edition of this book is an essential guide on expert techniques.
Table of Contents (20 chapters)
Title Page

The defer keyword

The defer keyword postpones the execution of a function until the surrounding function returns, which is widely used in file input and output operations because it saves you from having to remember when to close an opened file. The defer keyword allows you to put the function call that closes an opened file near to the function call that opened it. As you will learn about the use of defer in file-related operations in Chapter 8, Telling a UNIX System What to Do, this section will present two different usages of defer. You will also see defer in action in the section that talks about the panic() and recover() built-in Go functions, as well as in the section that is related to logging.

It is very important to remember that deferred functions are executed in last in, first out (LIFO) order after the return of the surrounding function. Putting it simply, this means...