Book Image

The Go Workshop

By : Delio D'Anna, Andrew Hayes, Sam Hennessy, Jeremy Leasor, Gobin Sougrakpam, Dániel Szabó
Book Image

The Go Workshop

By: Delio D'Anna, Andrew Hayes, Sam Hennessy, Jeremy Leasor, Gobin Sougrakpam, Dániel Szabó

Overview of this book

The Go Workshop will take the pain out of learning the Go programming language (also known as Golang). It is designed to teach you to be productive in building real-world software. Presented in an engaging, hands-on way, this book focuses on the features of Go that are used by professionals in their everyday work. Each concept is broken down, clearly explained, and followed up with activities to test your knowledge and build your practical skills. Your first steps will involve mastering Go syntax, working with variables and operators, and using core and complex types to hold data. Moving ahead, you will build your understanding of programming logic and implement Go algorithms to construct useful functions. As you progress, you'll discover how to handle errors, debug code to troubleshoot your applications, and implement polymorphism using interfaces. The later chapters will then teach you how to manage files, connect to a database, work with HTTP servers and REST APIs, and make use of concurrent programming. Throughout this Workshop, you'll work on a series of mini projects, including a shopping cart, a loan calculator, a working hours tracker, a web page counter, a code checker, and a user authentication system. By the end of this book, you'll have the knowledge and confidence to tackle your own ambitious projects with Go.
Table of Contents (21 chapters)
Free Chapter
1. Variables and Operators
2. Logic and Loops

Build Constraints

Go programs can run on different OSes and different CPU architectures. When you build a Go program, the compilation of your program is done for your current machine's OS and architecture. By using the build constraints, you can set conditions on which a file will be considered for compilation. If you have a function that needs to be overridden for different OSes, you can use build constraints to have multiple definitions of the same function.

You can see lots of examples of this happening in the Go standard library.

The following links are implementations of the same function in darwin and on Linux from the os package in the standard library:

If you happen to come across a similar requirement, the Go language provides build constraints that can be used to define build conditions.

Build Tags

There are two ways to use build constraints. The first method is to define build tags...