import (
	"encoding/json"
	"fmt"
)

type Bar interface {
	IsBar()
}

type Barred struct {
	Str string
}

func (Barred) IsBar() {

}

type Foo1 struct {
	Bar
	I int
}

type Foo2 struct {
	Barred
	I int
}

func main() {
	var b Barred = Barred{Str: "abc"}
	var f1 Foo1 = Foo1{Bar: b, I: 123}
	var f2 Foo2 = Foo2{Barred: b, I: 123}
	e1, _ := json.Marshal(f1)
	e2, _ := json.Marshal(f2)
	if string(e1) != string(e2) {
		fmt.Println("Interface and Structure marshalled differently")
	}
}