Go Standard Library Cookbook

How to do it...

1. Open the console and create the folder chapter10/recipe07.
2. Navigate to the directory.
3. Create the file lines.go with the following content:

        package main        import (          "bufio"          "context"          "fmt"          "log"          "strings"          "golang.org/x/sync/errgroup"        )        const data = `line one        line two with more words        error: This is erroneous line`        func main() {          log.Printf("Application %s starting.", "Error Detection")          scanner := bufio.NewScanner(strings.NewReader(data))          scanner.Split(bufio.ScanLines)          // For each line fire a goroutine          g, _ := errgroup.WithContext(context.Background())          for scanner.Scan() {            row := scanner.Text()            g.Go(func() error {              return func(s string) error {                if strings.Contains(s, "error:") {                  return fmt.Errorf(s)                }                return nil              }(row)            })          } // ...