我感觉个还好理解，

至少比当初入JAVA时更容易理解，

可能是以前的学习为现在打下了基础吧。

又或许是最近三年的程序编写，长了见识吧~

package main

import (
	"fmt"
)

type notifier interface {
	notify()
}

type user struct {
	name  string
	email string
}

type admin struct {
	user
	level string
}

func (u user) notify() {
	fmt.Printf("Sending User Email To %s<%s>\n",
		u.name,
		u.email)
}

func (u admin) notify() {
	fmt.Printf("Sending Admin Email To %s<%s>\n",
		u.name,
		u.email)
}

func (u *user) changeEmail(email string) {
	u.email = email
}

func main() {
	bill := user{"Bill", "bill@email.com"}
	sendNotification(bill)

	lisa := admin{
		user: user{
			name:  "Lisa",
			email: "lisa@email.com",
		},
		level: "super",
	}
	sendNotification(lisa)

}

func sendNotification(n notifier) {
	n.notify()
}