Panic and recover

Context

• panic stops normal execution, runs deferred functions, then terminates the program. It is used for unrecoverable errors.
• recover regains control after a panic. It must be called inside a deferred function. If the program is panicking, recover returns the panic value; otherwise it returns nil.

Example

Catch a panic and prevent program termination.

Code example

package main

import "fmt"

func mayPanic() {
    panic("something went wrong")
}

func main() {
    defer func() {
        if r := recover(); r != nil {
            fmt.Println("Recovered from panic:", r)
        }
    }()

    fmt.Println("Before panic")
    mayPanic()
    fmt.Println("This line will not be executed")
}

Output

Before panic
Recovered from panic: something went wrong

Useful links

• Go by Example: Panic and Recover
• Go spec: Handling panics