If we want to handle errors occurring in tasks externally, how could we do it?

In Go, when we run tasks (jobs) in goroutines, errors inside them are not returned directly because goroutines operate asynchronously. To handle errors externally, several approaches can be used:

1. Channels for error transmission: create an error channel, into which the goroutine sends the error, and the caller reads from the channel.

errCh := make(chan error)
go func() {
    err := doTask()
    errCh <- err
}()

err := <-errCh
if err != nil {
    // handle error
}

2. Using sync.WaitGroup and result structures: if multiple goroutines are launched, errors can be collected into a slice or map.

3. Context with cancellation: pass a context and cancel execution upon errors.

4. Wrappers with error return: if a task returns an error, it can be run in a function that returns an error, and handle it after completion.

Thus, for external error handling from tasks, errors need to be explicitly passed via channels or other structures, as Go does not support automatic error return from goroutines.