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

Go constants

Go supports constants, which are variables that cannot change their values. Constants in Go are defined with the help of the const keyword.

Generally speaking, constants are global variables, so you might rethink your approach if you find yourself defining too many constant variables with a local scope.

The main benefit you get from using constants in your programs is the guarantee that their value will not change during program execution. Strictly speaking, the value of a constant variable is defined at compile time not at run time.

Behind the scenes, Go uses Boolean, string, or number as the type for storing a constant variable because this gives Go more flexibility when dealing with constants.

You can define a new constant as follows:

const HEIGHT = 200 

Please note that in Go we do not use ALL CAPS for constants; this is just a personal preference of mine.