Multi tool use

Recover and continue for loop if panic occur Golang

so my case is quite complex but for asking question in clean and clear context I am using simple for loop that initiate from 0 and goes upto 10. Now what I am trying to do is when i becomes equal to 2 program will consider this as panic. It will go to recover state using defer and then after recovery loop will resume.

i becomes equal to 2

So desired output should be something like that:

0
1
panic occured: got 2
3
4
.
.
.
.
.
10


Actual output I am getting

0
1
panic occured got: got 2


Code block:

package main

import "fmt"

func main() {
goFrom1To10()
}

func goFrom1To10() {
defer recovery()
for i := 0; i <= 10; i++ {

if i == 2 {
panic("got 2")

}
fmt.Println(i)
}

}

func recovery() {
if r := recover(); r != nil {
fmt.Println("panic occured: ", r)
}

}


Can this be achievable in go like when panic occur somehow we can recover and complete our loop?

1 Answer
1

You can do that if the body of the loop is executed as a function, either anonymous or a named one, and in that function you use a deferred function to recover.

Here's how it looks like with anonymous functions:

func goFrom1To10() {
for i := 0; i <= 10; i++ {
func() {
defer func() {
if r := recover(); r != nil {
fmt.Println("panic occured: ", r)
}
}()

if i == 2 {
panic("got 2")
}
fmt.Println(i)
}()
}
}


Output (try it on the Go Playground):

0
1
panic occured: got 2
3
4
5
6
7
8
9
10


It's nicer and easier to understand if you move it to a named function:

func goFrom1To10() {
for i := 0; i <= 10; i++ {
task(i)
}
}

func task(i int) {
defer func() {
if r := recover(); r != nil {
fmt.Println("panic occured: ", r)
}
}()

if i == 2 {
panic("got 2")
}
fmt.Println(i)
}


Output is the same. Try this one on the Go Playground.

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