Understanding Go: Exploring Structs and Methods

Introduction:

Go is a statically typed, compiled programming language that offers a unique approach to object-oriented programming. Unlike languages such as C++ or Java, Go doesn’t have traditional classes. Instead, it utilizes structs and methods to achieve similar functionality. In this blog post, we’ll delve into a code snippet written in Go and explain how it works, step by step.

Code Explanation:

Let’s dissect the provided Go code snippet and understand its various components.

type Person struct {
	Name    string
	Surname string
	Hobbies []string
	id      string
}

func (person *Person) GetFullName() string {
	return fmt.Sprintf("%s %s", person.Name, person.Surname)
}
func main() {
	p := Person{
		Name:    "Mario",
		Surname: "Castro",
		Hobbies: []string{"cycling", "electronics", "planes"},
		id:      "sa3-223-asd",
	}

	fmt.Printf("%s likes %s, %s and %s\n", p.GetFullName(), p.Hobbies[0],
		p.Hobbies[1], p.Hobbies[2])
}

The above example is taken from book : Go Design Patterns

Defining the Person Struct:

The code begins with the declaration of a struct named Person. A struct is a composite data type that allows you to group together values of different types. In this case, the Person struct has four fields:

Name (string): Represents the person’s first name. Surname (string): Represents the person’s last name. Hobbies ([]string): Represents a list of hobbies the person has. It is a slice of strings, allowing multiple hobbies to be stored. id (string): Represents a unique identifier for the person.

Creating a Method on the Person Struct:

Next, we define a method named GetFullName() on the Person struct. In Go, a method is associated with a struct by declaring the method with a receiver type. In this case, the receiver type is a pointer to the Person struct (*Person). The purpose of this method is to concatenate the Name and Surname fields of a Person instance and return the full name as a string.

The main() Function:

Moving on to the main() function, we see the following steps:

Creating a Person Instance: We create a new instance of the Person struct named p using a struct literal. The values for the Name, Surname, Hobbies, and id fields are provided.

Calling the GetFullName() Method: Using the instance p, we call the GetFullName() method defined on the Person struct. This is achieved by using the dot notation (p.GetFullName()).

Printing the Result: The fmt.Printf() function is used to print a formatted string. The string includes the full name obtained from p.GetFullName() and the first three hobbies from the Hobbies field.

Output:

The final output of the program is the following string: “Mario Castro likes cycling, electronics, and planes”. This demonstrates that the code successfully retrieves the full name and prints it alongside the person’s hobbies.

Conclusion:

In conclusion, Go provides an alternative approach to object-oriented programming by utilizing structs and methods. Although Go doesn’t have classes like other languages, it allows you to associate methods with structs by defining a receiver type. This code snippet showcases the usage of structs and methods in Go, demonstrating how methods can be called on instances of a struct to perform specific operations. By understanding these concepts, developers can leverage Go’s unique approach to build efficient and concise code.