Book Image

Go Design Patterns

By : Mario Castro Contreras
Book Image

Go Design Patterns

By: Mario Castro Contreras

Overview of this book

Go is a multi-paradigm programming language that has built-in facilities to create concurrent applications. Design patterns allow developers to efficiently address common problems faced during developing applications. Go Design Patterns will provide readers with a reference point to software design patterns and CSP concurrency design patterns to help them build applications in a more idiomatic, robust, and convenient way in Go. The book starts with a brief introduction to Go programming essentials and quickly moves on to explain the idea behind the creation of design patterns and how they appeared in the 90’s as a common "language" between developers to solve common tasks in object-oriented programming languages. You will then learn how to apply the 23 Gang of Four (GoF) design patterns in Go and also learn about CSP concurrency patterns, the "killer feature" in Go that has helped Google develop software to maintain thousands of servers. With all of this the book will enable you to understand and apply design patterns in an idiomatic way that will produce concise, readable, and maintainable software.
Table of Contents (17 chapters)
Go Design Patterns
About the Author
About the Reviewer
Customer Feedback


Visibility is the attribute of a function or a variable to be visible to different parts of the program. So a variable can be used only in the function that is declared, in the entire package or in the entire program.

How can I set the visibility of a variable or function? Well, it can be confusing at the beginning but it cannot be simpler:

  • Uppercase definitions are public (visible in the entire program).

  • Lowercase are private (not seen at the package level) and function definitions (variables within functions) are visible just in the scope of the function.

Here you can see an example of a public function:

package hello 
func Hello_world(){ 
    println("Hello World!") 

Here, Hello_world is a global function (a function that is visible across the entire source code and to third party users of your code). So, if our package is called hello, we could call this function from outside of this package by using hello.Hello_world() method.

package different_package 
import "" 
func myLibraryFunc() { 

As you can see, we are in the different_package package. We have to import the package we want to use with the keyword import. The route then is the path within your $GOPATH/src that contains the package we are looking for. This path conveniently matches the URL of a GitHub account or any other Concurrent Versions System(CVS) repository.