# concurrent [](https://sourcegraph.com/github.com/modern-go/concurrent?badge) [](http://godoc.org/github.com/modern-go/concurrent) [](https://travis-ci.org/modern-go/concurrent) [](https://codecov.io/gh/modern-go/concurrent) [](https://goreportcard.com/report/github.com/modern-go/concurrent) [](https://raw.githubusercontent.com/modern-go/concurrent/master/LICENSE) * concurrent.Map: backport sync.Map for go below 1.9 * concurrent.Executor: goroutine with explicit ownership and cancellable # concurrent.Map because sync.Map is only available in go 1.9, we can use concurrent.Map to make code portable ```go m := concurrent.NewMap() m.Store("hello", "world") elem, found := m.Load("hello") // elem will be "world" // found will be true ``` # concurrent.Executor ```go executor := concurrent.NewUnboundedExecutor() executor.Go(func(ctx context.Context) { everyMillisecond := time.NewTicker(time.Millisecond) for { select { case <-ctx.Done(): fmt.Println("goroutine exited") return case <-everyMillisecond.C: // do something } } }) time.Sleep(time.Second) executor.StopAndWaitForever() fmt.Println("executor stopped") ``` attach goroutine to executor instance, so that we can * cancel it by stop the executor with Stop/StopAndWait/StopAndWaitForever * handle panic by callback: the default behavior will no longer crash your application