Chapter 1
Your First Command-Line Program in Go

Whether you’re looking to automate a task, analyze data, parse logs, talk to network services, or address other requirements, writing your own command-line tool may be the fastest—and perhaps the most fun—way to achieve your goal. Go is a modern programming language that combines the reliability of compiled languages with the ease of use and speed of dynamically typed languages. It makes writing cross-platform command-line applications more approachable while providing the features required to ensure these tools are well designed and tested.

Before you dive into more complex programs that read and write files, parse data files, and communicate over networks, you’ll create a word counter program that will give you an idea of how to build and test a command-line application using Go. You’ll start with a basic implementation, add some features, and explore test-driven development along the way. When you’re done, you’ll have a functional word counter program and a better understanding of how to build more complex apps.

Throughout the book you’ll develop other CLI applications to explore more advanced concepts.