Go/Structs

Lesson 4 of 8

Embedded Structs

Go does not have classes or classical inheritance. Instead, it uses embedded structs to provide a similar benefit of sharing fields between types.

Promotion

When you include a struct type within another struct without a field name, it is “embedded.” All the fields of the embedded struct are “promoted” to the top level of the parent struct.

type car struct {
    brand string
    model string
}

type truck struct {
    car     // Embedded!
    bedSize int
}

myTruck := truck{
    bedSize: 10,
    car: car{brand: "Ford", model: "F150"},
}

// Access promoted fields directly
fmt.Println(myTruck.brand) // Ford

Embedded vs. Nested

  • Nested: You must access fields through the property name (truck.car.brand).
  • Embedded: You access fields as if they were on the parent struct (truck.brand).

This is often used to compose larger structs out of smaller, reusable pieces without creating deep hierarchies.