Struct

Go provides a powerful way to define custom data types using structs. A struct is a composite data type that groups together variables (fields) under a single name. This allows you to create complex data structures that can represent real-world entities. Structs are defined using the struct keyword, followed by a list of fields enclosed in curly braces. Each field has a name and a type.

   
   type Person struct {
       Name string
       Age  int
   }

The code above defines a struct named Person with two fields: Name of type string and Age of type int. You can create an instance of a struct by using the struct type as a constructor.

package main

 import "fmt"

 type Person struct {
     Name string
     Age  int
 }

 func main() {
     person := Person{Name: "John", Age: 30}
     fmt.Println(person.Name) // Output: John
     fmt.Println(person.Age)  // Output: 30
 }

Anonymous Structs

Anonymous structs are structs that do not have a name. They are useful when you need a temporary data structure without defining a separate type. You can create an anonymous struct by using the struct keyword directly.

package main

 import "fmt"

 func main() {
     person := struct {
         Name string
         Age  int
     }{
         Name: "Alice",
         Age:  25,
     }

     fmt.Println(person.Name) // Output: Alice
     fmt.Println(person.Age)  // Output: 25
 }

Struct Tags

Struct tags are annotations that can be added to struct fields. They are often used for serialization, validation, and other purposes. Tags are defined as a string literal following the field type.

   type Person struct {
       Name string `json:"name"`
       Age  int    `json:"age"`
   }

In the example above, the struct fields Name and Age have JSON tags that specify how they should be serialized to JSON. The json:"name" tag indicates that the Name field should be represented as "name" in the JSON output.