goroutine error: too many arguments to return

Question

I have a function works before using goroutine:

res, err := example(a , b)
if err != nil {
 return Response{
   ErrCode: 1,
   ErrMsg:"error",
 }
}

Response is a struct defined error info. When I use goroutine:

var wg sync.WaitGroup()
wg.Add(1)
go func(){
   defer wg.Done()
   res, err := example(a , b)
   if err != nil {
      return Response{
         ErrCode: 1,
         ErrMsg:"error",
    }
}()
wg.Wait()

Then I got

too many arguments to return
    have (Response)
    want ()

Answer 1

You need to use channel to achieve what you want:

func main() {
    c := make(chan Response)
    go func() {
        res, err := example(a , b)
        if err != nil {
            c <- Response{
                ErrCode: 1,
                ErrMsg:"error",
            }
        }
    }()
    value := <-c
}