In Go, a defer statement will execute a function call just before the function it is called from returns.

I found that most of the examples of a Go defer call online seemed to do complicated things with numbers. So here is a nice simple example with just text output.

Example

You can run this code yourself in The Go Playground! You can also find a similar example in the Go Tour.

package main import ( "fmt" ) func main() { // This will output first (in order) fmt.Println("One") // This will output last (before this function finishes) defer fmt.Println("Two") // This will be called before the above defer call "Two" secondary() } func secondary() { // This will output after Four (before this function finishes) defer fmt.Println("Three") // This will output (in order) fmt.Println("Four") }
Code language: JavaScript (javascript)

Output:

One Four Three Two

If you get something else, you’re doing something wrong ;)