What are pointers in Golang?

In Golang, a pointer is a variable that stores the address of an object stored in memory. All the variables that contain data of different types, such as int or string, are stored in memory, and a pointer “points” to these variables. These memory addresses are in the hexadecimal format, for example, 0x11AA3.

Note: In Golang, pointers are known as special variables.

Let’s understand pointers through a diagram:

The illustration above shows two variables of type int and string stored in the memory. The int variable stores a value of 10, while the string variable stores the value “educative”. Two pointers, a and b, point towards the memory location of the respective variables, that is, they store the addresses.

Declaring a pointer

There are two important operators that are associated with pointers:

* Operator: This is also called a dereferencing operator. It is used for the declaration of a pointer, as well as for accessing the value stored at the address that the pointer is pointing to.
& Operator: This is known as an address operator. It is used to get the address of a variable.

The syntax for declaring a pointer in Golang is:

var name *Type

name: This is the name of the pointer variable.
Type: This is the data type of the variable that the pointer points to.

Let’s look at an example of a pointer of type string:

var myPointer *string

Initialization of a pointer

The initialization of a pointer requires the use of the address operator to store the memory address of a variable in the pointer.


// variable whose address the pointer will store 
var intData = 15 

//initialization of a pointer of int type that stores
//the memory address of intData
var intPointer *int = &intData

package main
import "fmt"
/* For exercises uncomment the imports below */
// import "strconv"
// import "encoding/json"
func main() {
    // a normal variable  whose address the pointer will store 
    var intData = 20 
    
    //declaration of a pointer 
    var intPointer *int
    //intPointer now points towards intData    
    intPointer = &intData 
    fmt.Println("what intData stores:", intData)
    fmt.Println("address of intData:", &intData)
    fmt.Println("what intPointer stores:", intPointer)
    //this updates the value of intData using dereferncing operator 
    *intPointer = 30
    fmt.Println("what intData now stores:", intData)
}

What are pointers in Golang?

Declaring a pointer

Initialization of a pointer

Code

Code explanation