如何初始化继承对象的字段

Question

I must be missing something. I cannot initialize an object's inherited fields without directly accessing them.

My goal is trying to keep it simple.

package main

type Page struct {
  Title string
}

type Article struct {
  Page
  Id int
}

func main() {

  // this generates a build error: 
  // "invalid field name Title in struct initializer"
  //
  p := &Article{
    Title: "Welcome!",
    Id:    2,
  }

  // this generates a build error: 
  // "invalid field name Page.Title in struct initializer"
  //
  p := &Article{
    Page.Title: "Welcome!",
    Id:         2,
  }

  // this works, but is verbose...  trying to avoid this
  //
  p := &Article{
    Id:    2,
  }
  p.Title = "Welcome!"

  // as well as this, since the above was just a shortcut
  //
  p := &Article{
    Id:    2,
  }
  p.Page.Title = "Welcome!"

}

Thanks in advance.

Answer 1

In Go, these fields from embedded structs are called promoted fields.

The Go Specification states (my emphasis):

Promoted fields act like ordinary fields of a struct except that they cannot be used as field names in composite literals of the struct.

This is how you can solve it:

p := &Article{
    Page: Page{"Welcome!"},
    Id:   2,
}