gob.Register（）按类型还是每个变量？

Question

I am doing something like this in my code

test1 = make(map[string]interface{})
test2 = make(map[string]interface{})
test3 = make(map[string]interface{})
test4 = make(map[string]interface{})

gob.Register(test1)
gob.Register(test2)
gob.Register(test3)
gob.Register(test4)

It compiles but am I suppose to be doing it that way? Or do I just need to register one of them because they have the same type?

gob.Register(test1)

Answer 1

As per https://golang.org/pkg/encoding/gob/#Register -

Register records a type, identified by a value for that type, under its internal type name.

Register the empty type - e.g.

gob.Register(map[string]interface{}{})

Full example:

func main() {
    gob.Register(map[string]interface{}{})
    a := map[string]interface{}{
        "X":        1,
        "Greeting": "hello",
    }
    buf := new(bytes.Buffer)
    err := gob.NewEncoder(buf).Encode(a)
    if err != nil {
        log.Fatal(err)
    }

    fmt.Println(buf.Bytes())

    val := make(map[string]interface{})
    err = gob.NewDecoder(buf).Decode(&val)
    if err != nil {
        log.Fatal(err)
    }

    fmt.Printf("%+v
", val)
}

Run it here: http://play.golang.org/p/e5vXER_dz-