Structures in GoLang

In Go, a struct is a composite data type that groups together variables (fields) under a single name. Each field in a struct can have a different data type. Structs are used to represent real-world entities with multiple properties.

Key Features of Structures in Go:

• Defined with the struct keyword.
• Fields can have different types.
• No inheritance, but you can embed structs in other structs (composition).
• Pass by value: When you pass a struct to a function, a copy of the struct is made.

Defining a Struct

A struct is defined using the struct keyword, followed by the fields of the struct.

import "fmt"// Defining a structtype Person struct {    Name    string    Age     int    Address string}func main() {    var person1 Person
fmt.Println(person1) // Output: {"" 0 ""}

person1 := &Person{Name: "John", Age: 30, Address: "1234 Elm Street"}
fmt.Println(person1.Name) // Accessing the field through the pointer

Accessing and Modifying Fields

Fields in a struct can be accessed and modified using the dot (.) notation.

package main
import "fmt"type Person struct {    Name    string    Age     int    Address string}func main() {    person1 := Person{Name: package main
import "fmt"type Person struct {    Name  string    Age   int}func (p Person) Greet() {    fmt.Println(func main() {    person1 := Person{Name: package main
import "fmt"type Person struct {    Name  string    Age   int}func (p *Person) HaveBirthday() {    p.Age += func main() {    person1 := &Person{Name: package main
import "fmt"// Defining the inner structtype Address struct {    Street string    City   string    State  string}// Defining the outer struct with a nested structtype Person struct {    Name    string    Age     int    Address Address}func main() {    person1 := Person{        Name: package main
import "fmt"func main() {    package main
import "fmt"type Person struct {    Name  string    Age   int}func main() {    package main
import "fmt"import "encoding/json"// Defining struct with tagstype Person struct {    Name   string `json:"name"`    Age    int    `json:"age"`    Gender string `json:"gender"`}func main() {    person := Person{Name: "John", Age: 30, Gender: "Male"}    // Convert struct to JSON    jsonData, _ := json.Marshal(person)    fmt.Println(string(jsonData)) // Output: {"name":"John","age":30,"gender":"Male"}}

Summary

• Structs in Go are used to represent objects or entities with multiple properties.
• Fields in structs can have different data types.
• Structs can be passed by value or by reference (using pointers).
• Methods can be defined on structs to encapsulate behavior.
• Go does not support inheritance, but structs can be composed by embedding other structs.
• Struct tags are used for metadata purposes, particularly with libraries like encoding/json.

Structs are one of the most important data structures in Go, helping to model complex real-world entities. They allow you to group related data together and apply methods for manipulating this data.