Panic Stack

What will be printed when the code below is executed? 

  1. package main
  3. func f1() {
  4.     defer println("f1-begin")
  5.     f2()
  6.     defer println("f1-end")
  7. }
  9. func f2() {
  10.     defer println("f2-begin")
  11.     f3()
  12.     defer println("f2-end")
  13. }
  15. func f3() {
  16.     defer println("f3-begin")
  17.     panic(0)
  18.     defer println("f3-end")
  19. }
  21. func main() {
  22.     f1()
  23. }

Answer

  1. f3-begin
  2. f2-begin
  3. f1-begin
  4. panic: 0
  6. goroutine 1 [running]:
  7. main.f3()
  8. /tmp/sandbox423933384/main.go:17 +0x80
  9. main.f2()
  10. /tmp/sandbox423933384/main.go:11 +0x80
  11. main.f1()
  12. /tmp/sandbox423933384/main.go:5 +0x80
  13. main.main()
  14. /tmp/sandbox423933384/main.go:22 +0x20