Panic & Recover

基本用法

• recover 位置，需要与 panic 在同一个 goroutine 中

package main
import (
    "fmt"
    "time"
)
func main() {
    defer func() {
        if err := recover(); err != nil {
            fmt.Println("Recover in main from error:", err)
        }
        fmt.Println("Execution finished")
    }()
    go func() {
        panic("panic in goroutine")
    }()
    time.Sleep(1 * time.Second)
}

• 可在 recover 中再次抛出 panic

package main
import (
    "fmt"
)
func main() {
    defer func() {
        defer func() {
            if err := recover(); err != nil {
                fmt.Println("Recover from error:", err)
            }
        }()
        if err := recover(); err != nil {
            fmt.Println("Recover from error:", err)
            panic("again")
        }
    }()
    panic("whatever")
}