Book Image

Mastering Go – Third Edition - Third Edition

By : Mihalis Tsoukalos
5 (2)
Book Image

Mastering Go – Third Edition - Third Edition

5 (2)
By: Mihalis Tsoukalos

Overview of this book

Mastering Go is the essential guide to putting Go to work on real production systems. This freshly updated third edition includes topics like creating RESTful servers and clients, understanding Go generics, and developing gRPC servers and clients. Mastering Go was written for programmers who want to explore the capabilities of Go in practice. As you work your way through the chapters, you’ll gain confidence and a deep understanding of advanced Go concepts, including concurrency and the operation of the Go Garbage Collector, using Go with Docker, writing powerful command-line utilities, working with JavaScript Object Notation (JSON) data, and interacting with databases. You’ll also improve your understanding of Go internals to optimize Go code and use data types and data structures in new and unexpected ways. This essential Go programming book will also take you through the nuances and idioms of Go with exercises and resources to fully embed your newly acquired knowledge. With the help of Mastering Go, you’ll become an expert Go programmer by building Go systems and implementing advanced Go techniques in your projects.
Table of Contents (17 chapters)
14
Other Books You May Enjoy
15
Index

Interfaces versus generics

This section presents a program that increments a numeric value by one using interfaces and generics so that you can compare the implementation details.

The code of interfaces.go illustrates the two techniques and contains the next code:

package main
import (
    "fmt"
)
type Numeric interface {
    type int, int8, int16, int32, int64, float64
}

This is where we define a constraint named Numeric for limiting the permitted data types.

func Print(s interface{}) {
    // type switch
    switch s.(type) {

The Print() function uses the empty interface for getting input and a type switch to work with that input parameter.

Put simply, we are using a type switch to differentiate between the supported data types—in this case, the supported data types are just int and float64, which has to do with the implementation of the type switch. However, adding more data types requires code changes, which is not the most efficient...