方法重载时，Golang结构调用嵌入式类型方法

Question

I am trying to learn Go, and I found a good resource here.

The example given on method overloading is reproduced below:

package main
import "fmt"

type Human struct {
    name string
    age int
    phone string
}


type Employee struct {
    Human 
    company string
}

func (h *Human) SayHi() {
    fmt.Printf("Hi, I am %s you can call me on %s
", h.name, h.phone)
}

func (e *Employee) SayHi() {
    fmt.Printf("Hi, I am %s, I work at %s. Call me on %s
", e.name,
        e.company, e.phone) //Yes you can split into 2 lines here.
}

func main() {
    sam := Employee{Human{"Sam", 45, "111-888-XXXX"}, "Golang Inc"}
    sam.SayHi()
}

Is it possible to call the "base" struct's (Human's) methods, eg. sam.Human.SayHi() Downcasting doesn't work (because there is no type hierarchy right?)

Answer 1

You can access the embedded struct of a parent struct by calling the member of the parent with the name of the embedded type's name. That's a mouthful, so it's probably easier to demonstrate it.

 sam := Employee{Human{"Sam", 45, "111-888-XXXX"}, "Golang Inc"}
 sam.SayHi() // calls Employee.SayHi
 sam.Human.SayHi() // calls Human.SayHi

Outputs

 Hi, I am Sam, I work at Golang Inc. Call me on 111-888-XXXX
 Hi, I am Sam you can call me on 111-888-XXXX