What are Pointers to a Function in Go Programming? | Go Language Tutorial
What are Pointers to a Function in Go Programming? | Go Language Tutorial
In this article, you will learn about what are pointers to a function in Go Programming.
Pointers in GoLang is a variable that is used to store the memory address of another variable. The user can also pass the pointers to the function like the variables. There are two ways to pass the pointers to the function.
- Create a pointer and simply pass it to the Function:
In the program written below, we are taking a function abc which has an integer-type pointer parameter. It gives the instructions to the function to accept only the pointer-type argument. Fundamentally, the function changed the value of the variable x. Initially, x has a value of 220. But after the function call, the value changed to 680, as visible in the output:
Example:
package main import "fmt" // type pointer as an parameterfunc abc(val *int) { // dereferencing *val = 680} // Main functionfunc main() { // normal variable var y = 250 fmt.Printf("The value of y before function call is: %d\n", y) //assigning the addressof y to it var b *int = &y // passing pointer to function abc(pa) fmt.Printf("The value of y after function call is: %d\n", y)}Output:
The value of y before function call is: 250
The value of y after function call is: 680
- Passing an address of the variable to the function call:
We are not creating pointers to store the address of the variable i.e, similar to the y variable in the above program. We are passing the address of a to the function call which works as it is discussed above.
Example:
package main import "fmt" // pointer type as an parameterfunc abc(val *int) { // dereferencing *val = 680} // Main functionfunc main() { // normal variable var y = 220 fmt.Printf("The value of y before function call is: %d\n", y) // passing the address ofthe variable y ptf(&y) fmt.Printf("The value of y after function call is: %d\n", y) }
