如何使用 gob 對介面進行編碼

package main

import (
    "encoding/gob"
    "fmt"
    "os"
)

type User struct {
    Username string
    Password string
}

type Admin struct {
    Username string
    Password string
    IsAdmin  bool
}

type Deleter interface {
    Delete()
}

func (u User) Delete() {
    fmt.Println("User ==> Delete()")
}

func (a Admin) Delete() {
    fmt.Println("Admin ==> Delete()")
}

func main() {

    user := User{
        "zola",
        "supersecretpassword",
    }

    admin := Admin{
        "john",
        "supersecretpassword",
        true,
    }

    file, _ := os.Create("user.gob")

    adminFile, _ := os.Create("admin.gob")

    defer file.Close()

    defer adminFile.Close()

    gob.Register(User{}) // registering the type allows us to encode it

    gob.Register(Admin{}) // registering the type allows us to encode it

    encoder := gob.NewEncoder(file)

    adminEncoder := gob.NewEncoder(adminFile)

    InterfaceEncode(encoder, user)

    InterfaceEncode(adminEncoder, admin)

}

func InterfaceEncode(encoder *gob.Encoder, d Deleter) {

    if err := encoder.Encode(&d); err != nil {
        fmt.Println(err)
    }

}