Implementing class(OOP style)

gistfile1.go

 package main

 import (
 	"fmt"
 )

 type SayHelloIntFace interface {
 	SayHello()
 }

 type Person struct{}

 // this method is tied to Person class
 func (person Person) SayHello() {
 	fmt.Printf("Hello!")
 }

 type Dog struct{}

 // this method is tied to Dog class
 func (dog Dog) SayHello() {
 	fmt.Printf("woof! woof!")
 }

 func greeting(i SayHelloIntFace) {
 	i.SayHello()
 }

 func main() {
 	// instantiate objects
 	person := Person{}
 	dog := Dog{}

 	var i SayHelloIntFace

 	fmt.Println("\nPerson : ")
 	i = person
 	greeting(i)

 	fmt.Println("\n\nDog : ")
 	i = dog
 	greeting(i)

 }