当某个协程出现错误时，通过recover捕获panic，使得主线程中的其他协程能继续运行 ``` package main import ( "fmt" "time" ) func sayHello() { for i := 0; i < 10; i++ {         time.Sleep(time.Second)         fmt.Printf("hello world\\n")     } } func test() { defer func() { //捕获test抛出的panic if err := recover(); err != nil {             fmt.Println("test()发生错误", err) }     }() var myMap map[int]string     myMap[0] = "GOLANG" } func main() { go sayHello() go test() for i := 0; i < 10; i++ {         fmt.Println("main() ok=", i)         time.Sleep(time.Second)     } } ```