Go panic() recover() and defer()
Go panic() recover() and defer()
```go package main
import ( “fmt” // “strconv” // “math” // “reflect” “net/http” “log”
)
func simplePanic() { a, b := 1, 0 ans := a/b fmt.Printf(“ans: %v\n”, ans) }
func usePanic() { fmt.Printf(“start\n”) panic(“something bad happened”) fmt.Printf(“end\n”) }
func panicInWebAPP() { http.HandleFunc(“/”, func (w http.ResponseWriter, r *http.Request) { w.Write([]byte(“Hello Go!”)) })
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err := http.ListenAndServe(":8000", nil)
if err != nil {
panic(err.Error())
}
}
func deferIsExecutedBeforePanic() { fmt.Printf(“start\n”) defer fmt.Printf(“this was defered\n”) panic(“something bad happened”) fmt.Printf(“end\n”) }
func xdeferIsExecutedBeforePanic() { fmt.Printf(“start\n”) defer func() { if err := recover(); err != nil { log.Printf(“Something bad happended error: %v\n”, err) // if the error is so bad // simply use: // panic(“I cannot handle it anymore :)”) }
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}()
panic("Panic something bad happened\n")
fmt.Printf("end\n") }
func main() { // simplePanic() // usePanic() // panicInWebAPP() xdeferIsExecutedBeforePanic() fmt.Printf(“end\n”) } ``