this topic is about Go – Passing pointers to functions. Go programming language allows you to pass a pointer to a function. To do so, simply declare the function parameter as a pointer type.
In the following example, we pass two pointers to a function and change the value inside the function which reflects back in the calling function −
package main
import "fmt"
func main() {
/* local variable definition */
var a int = 100
var b int = 200
fmt.Printf("Before swap, value of a : %d\n", a )
fmt.Printf("Before swap, value of b : %d\n", b )
/* calling a function to swap the values.
* &a indicates pointer to a ie. address of variable a and
* &b indicates pointer to b ie. address of variable b.
*/
swap(&a, &b);
fmt.Printf("After swap, value of a : %d\n", a )
fmt.Printf("After swap, value of b : %d\n", b )
}
func swap(x *int, y *int) {
var temp int
temp = *x /* save the value at address x */
*x = *y /* put y into x */
*y = temp /* put temp into y */
}
When the above code is compiled and executed, it produces the following result −
Before swap, value of a :100 Before swap, value of b :200 After swap, value of a :200 After swap, value of b :100
To know more, Click Here.
Pingback: Go - Pointer to pointer - Adglob Infosystem Pvt Ltd
Pingback: Go - Pointers - Adglob Infosystem Pvt Ltd