27.Stacking defers - Programming in GO

Stacking defers

Deferred function calls are pushed onto a stack. When a function returns, its deferred calls are executed in last-in-first-out order.

lets write a program to count numbers from 1 to 9

package main

import "fmt"

func main() {
	fmt.Println("counting")

	for i := 0; i < 10; i++ {
		 fmt.Println(i)
	}

	fmt.Println("done")
}

Go Playground

Stacking defers - use defer defer fmt.Println(i). because of defer its give you output of last result in first thats known as last-in-first out manner

package main

import "fmt"

func main() {
	fmt.Println("counting")

	for i := 0; i < 10; i++ {
		 defer fmt.Println(i)
	}

	fmt.Println("done")
}

Go Playground

Important:

	for i := 0; i < 10; i++ {
		 defer fmt.Println(i)
	}

output:

counting
done
9
8
7
6
5
4
3
2
1
0