Book Image

Learning Go Programming

Book Image

Learning Go Programming

Overview of this book

The Go programming language has firmly established itself as a favorite for building complex and scalable system applications. Go offers a direct and practical approach to programming that let programmers write correct and predictable code using concurrency idioms and a full-featured standard library. This is a step-by-step, practical guide full of real world examples to help you get started with Go in no time at all. We start off by understanding the fundamentals of Go, followed by a detailed description of the Go data types, program structures and Maps. After this, you learn how to use Go concurrency idioms to avoid pitfalls and create programs that are exact in expected behavior. Next, you will be familiarized with the tools and libraries that are available in Go for writing and exercising tests, benchmarking, and code coverage. Finally, you will be able to utilize some of the most important features of GO such as, Network Programming and OS integration to build efficient applications. All the concepts are explained in a crisp and concise manner and by the end of this book; you would be able to create highly efficient programs that you can deploy over cloud.
Table of Contents (18 chapters)
Learning Go Programming
About the Author
About the Reviewers

Function panic and recovery

Earlier in the chapter, it was stated that Go does not have the traditional exception mechanism offered by other languages. Nevertheless, in Go, there is a way to abruptly exit an executing function known as function panic. Conversely, when a program is panicking, Go provides a way of recovering and regaining control of the execution flow.

Function panic

During execution, a function may panic because of any one of following:

  • Explicitly calling the panic built-in function

  • Using a source code package that panics due to an abnormal state

  • Accessing a nil value or an out-of-bound array element

  • Concurrency deadlock

When a function panics, it aborts and executes its deferred calls. Then its caller panics, causing a chain reaction as illustrated in the following figure:

The panic sequence continues all the way up the call stack until the main function is reached and the program exits (crashes). The following source code snippet shows a version of the anagram program that will...