### 超子集轉換 超集可以轉換為子集,反過來是不可以的. ~~~ type Animal interface { sayhi() } type Humaner interface { Animal sing(lrc string) } type Person struct { name string age int } func (p *Person) sayhi() { fmt.Println(p.name, p.age) } func (p *Person) sing(lrc string) { fmt.Println("聽周杰倫在唱:", lrc) } func main() { var humaner Humaner //超集 var animal Animal //子集 humaner = &Person{"jack",18} fmt.Println(humaner) animal = humaner fmt.Println(animal) } ~~~ ~~~ &{jack 18} &{jack 18} ~~~