I have this simple program below
package main
import (
"fmt"
"sync"
"time"
)
var wg sync.WaitGroup
func main() {
wg.Add(1)
go func() {
fmt.Println("starting...")
time.Sleep(1 * time.Second)
fmt.Println("done....")
wg.Done()
} ()
wg.Wait()
}
Notice that I use var wg sync.WaitGroup
as a value, not a pointer. But the page for the sync package specifies that the Add
, Done
and Wait
function take a *sync.WaitGroup
.
Why/How does this work?
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