Mastering Go - Second Edition

How not to use goroutines

In this section, you are going to see a naive way to sort natural numbers using goroutines. The name of the program is sillySort.go and it will be presented in two parts. The first part of sillySort.go is the following:

package main 
 
import ( 
    "fmt" 
    "os" 
    "strconv" 
    "sync" 
    "time" 
) 
 
func main() { 
    arguments := os.Args 
 
    if len(arguments) == 1 { 
        fmt.Println(os.Args[0], "n1, n2, [n]") 
        return 
    } 
 
    var wg sync.WaitGroup 
    for _, arg := range arguments[1:] { 
        n, err := strconv.Atoi(arg) 
        if err != nil || n < 0 { 
            fmt.Print(". ") 
            continue 
        } 

The second part of sillySort.go contains the following Go code:

 wg.Add(1) go func(n int) { defer wg.Done() time.Sleep(time.Duration(n) * time.Second) fmt.Print(n, " ") }(n) } wg.Wait() fmt.Println() ...