Go struct embedding

In Go, embedding refers to the ability to embed one type into another, allowing us to achieve:

Code reusability: Embedding is useful for sharing common behaviors between types without explicitly inheriting from a base class.
Composition: It enables the composition of types, meaning that a type can include other types and, therefore, inherit their behaviors.
Functionality extension: It is used to extend the functionality of an existing type by incorporating other types that provide additional features.
Simplicity and clarity: It can simplify and make the design of types clearer by allowing a more modular and easy-to-understand structure.

If you are new to the world of Go, I recommend the following previous articles:

In this simple example, we have three structures:

person: Common structure.
student: Inherits from person and additionally adds the string grade.
teacher: Inherits from person and additionally adds the int teaching_years.

vi university.go

package main

import "fmt"

type person struct {
    name string
    age int
}

func (p person) introduction() {
    fmt.Printf("Hello, I'm %s and I'm %d years old.\n", p.name, p.age)
}

type student struct {
    person
    grade string
}

func (s student) study() {
    fmt.Printf("%s is studying in %s.\n", s.name, s.grade)
}

type teacher struct {
    person
    teaching_years int
}

func (t teacher) teaching() {
    fmt.Printf("%s has been teaching %d years.\n", t.name, t.teaching_years)
}

func main() {
    student := student{
        person: person{
            name: "Ana",
            age:   20,
        },
        grade: "engineering",
    }
    teacher := teacher{
        person: person{
            name: "Joe",
            age:   30,
        },
        teaching_years: 10,
    }

    student.introduction()
    student.study()
    fmt.Println("-----")
    teacher.introduction()
    teacher.teaching()
}

Let’s execute the code:

go run university.go

We can see how each object shares the fields defined in the person structure (name/age) and also has their respective specific additional fields (grade/teaching_years), besides person, student and teacher structures have a common function introduction and one own function study and teaching respectively due to the Go methods :

Hello, I'm Ana and I'm 20 years old.
Ana is studying in engineering.
-----
Hello, I'm Joe and I'm 30 years old.
Joe has been teaching 10 years.