Can you share an example of how you implemented error handling using error.Group in your projects?

The errors package with the Group type (for example, from golang.org/x/sync/errgroup) allows convenient collection and handling of multiple errors that occur in parallel goroutines.

Example of using errgroup.Group for parallel task execution with error handling:

import (
    "fmt"
    "golang.org/x/sync/errgroup"
)

func processTasks() error {
    var g errgroup.Group

    tasks := []func() error{
        func() error { /* task 1 */ return nil },
        func() error { /* task 2 */ return fmt.Errorf("error in task 2") },
        func() error { /* task 3 */ return nil },
    }

    for _, task := range tasks {
        t := task
        g.Go(func() error {
            return t()
        })
    }

    if err := g.Wait(); err != nil {
        // handle the first encountered error
        return err
    }
    return nil
}

In my projects, I used errgroup to run several independent operations in parallel and to collect errors neatly, which simplifies code and improves readability.