go 空接口和结构体类型判断,

package main

import (
"fmt"
)

type Animal interface {
Talk()
Eat()
Name() string
}

type Dog struct {
}

func (d Dog) Talk() {
fmt.Println("汪汪汪")
}

func (d Dog) Eat() {
fmt.Println("我在吃骨头")
}

func (d Dog) Name() string {
fmt.Println("我的名字叫旺财")
return "旺财"
}

type Pig struct {
}

func (d Pig) Talk() {
fmt.Println("坑坑坑")
}

func (d Pig) Eat() {
fmt.Println("我在吃草")
}

func (d Pig) Name() string {
fmt.Println("我的名字叫猪八戒")
return "猪八戒"
}

func testInterface1() {
var d Dog
var a Animal
a = &d

a.Eat()
a.Talk()
a.Name()

var pig Pig
a = &pig
a.Eat()
a.Talk()
a.Name()

fmt.Printf("%T %v\n", a, a)

}

func just(a Animal) {
//d, ok := a.(Dog)
//p, ok := a.(Pig)
switch v := a.(type) {
case Dog:
fmt.Printf("v is dog, %v\n", v)
case Pig:
fmt.Printf("v is dog, %v\n", v)
default:
fmt.Printf("not support")
}
}

func testInterface2() {
var d Dog
just(&d)
}

func main() {
testInterface1()

//testInterface2()

}