如何共享嵌入式结构指针

Question

I have following code:

A struct controller, that have anonymous fields.

type controller struct {
    *base.Controller
    store *data
}

As you can see, *base.Controller is anonymous fields pointer. Then a second struct that composed with *base.Controller too.

type expiredError struct {
    *base.Controller
    local string
}

I initialized the controller struct as follow:

c := &controller{base.New(rw, r, false, "controller/account"), nil}
c.Title = "Activate account"
c.serve()

The base.Controller on controller is initialize with base.New() function.

Now I have on controller methods, that initialize the expiredError struct and it should share the pointer of base.Controller to base.Controller of expiredError too.

func (rcv *controller) validate() error {

    ....

    // If time for activating account is expired
    if time.Now().Unix() > rcv.store.Expired {
        // Delete registered user from neo4j
        maccount.Delete(rcv.store.Email, rcv.Local)

        return &expiredError{base.Controller, rcv.Local}
    }

    return nil
}

I've got here a compiler error

type base.Controller is not an expression

Answer 1

You can try referencing the anonymous field by mentioning the instance of the parent class:

rcv.Controller

(since the "name" of an anonymous field is the same as the type of the field)

See a similar example in:

• "Anonymous fields in structs - like object composition",
• "Methods on structs".