The Go code, in its entirety:

    type HasName interface { Name() string }
    
    func Greet(n HasName) { fmt.Printf("Hello %s!\n", n.Name()) }
    
    type Joe struct {}
    
    func (_ *Joe) Name() string { return "Joe" }
    
    type Mike struct {}
    
    func (_ *Mike) Name() string { return "Mike" }
    
    func main() {
            joe := &Joe{}
            mike := &Mike{}
            Greet(mike)
            Greet(joe)
    }

You have no idea how to read this?