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
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface

Higher-order functions


We have already established that Go functions are values bound to a type. So, it should not be a surprise that a Go function can take another function as a parameter and also return a function as a result value. This describes the notion known as a higher-order function, which is a concept adopted from mathematics. While types such as struct let programmers abstract data, higher-order functions provide a mechanism to encapsulate and abstract behaviors that can be composed together to form more complex behaviors.

To make this concept clearer, let us examine the following program, which uses a higher-order function, apply, to do three things. It accepts a slice of integers and a function as parameters. It applies the specified function to each element in the slice. Lastly, the apply function also returns a function as its result:

package main 
import "fmt" 
 
func apply(nums []int, f func(int) int) func() { 
   for i, v := range nums { 
      ...