main.go

/*

Basic Golang struct embedding example

Try it here: https://play.golang.org/p/HGfzu4m6AB8

*/

package main

import (
	"fmt"
)


type Printer interface {
	Print()
}

type PrettyPrinter interface {
	PrettyPrint()
}

func PrintAny(x interface{}) {
	switch x2 := x.(type) {
	case PrettyPrinter:
		x2.PrettyPrint()
	case Printer:
		x2.Print()
	default:
		fmt.Printf("fallback: %v\n", x2)
	}
}


type Node interface{}

type BasicNode struct {
	ID string
}

type SpecialNode struct {
	*BasicNode
}

func (n SpecialNode) Print() {
	fmt.Printf("Print: %s\n", n.ID)
}

type PrettyNode struct {
	*SpecialNode
}

func (n PrettyNode) PrettyPrint() {
	fmt.Printf("PrettyPrint: %s\n", n.ID)
}


func printer(n Node) {
	PrintAny(n)
}

func main() {
	n := &BasicNode{"Node-1"}
	PrintAny(n)
	printer(n)

	sn := &SpecialNode{&BasicNode{"SpecialNode-1"}}
	PrintAny(sn)
	printer(sn)
	
	pn := &PrettyNode{&SpecialNode{&BasicNode{"PrettyNode-1"}}}
	PrintAny(pn)
	printer(pn)	
}