Showing an alternate way to support OO in go (original reference http://www.goinggo.net/2013/07/object-oriented-programming-in-go.html)

gistfile1.go

package main

import (
  "fmt"
)

type Animal struct {
	Name string
	mean bool
}

type AnimalSound interface {
	MakeNoise()
}

type Dog struct {
	Animal
	BarkStrength int
}

type Cat struct {
	Basics       Animal
	MeowStrength int
}

func main() {

	myDog := &Dog{Animal{"rover", false}, 2}
	// you can now reference myDog.Name and myDog.mean alongside myDog.BarkStrength

	myCat := &Cat{
		Basics: Animal{
			Name: "Julius",
			mean: true,
		},
		MeowStrength: 3,
	}

	MakeSomeNoise(myDog)
	MakeSomeNoise(myCat)
}

func (animal *Animal) MakeNoise(strength int, sound string) {

	if animal.mean == true {

		strength = strength * 5
	}

	for voice := 0; voice < strength; voice++ {

		fmt.Printf("%s ", sound)
	}

	fmt.Printf("\n")
}

func (dog *Dog) MakeNoise() {

	dog.Animal.MakeNoise(dog.BarkStrength, "BARK")
}

func (cat *Cat) MakeNoise() {

	cat.Basics.MakeNoise(cat.MeowStrength, "MEOW")
}

func MakeSomeNoise(animal AnimalSound) {

	animal.MakeNoise()
}