improve README example

README.md

@@ -7,28 +7,39 @@ cycle-scheduler is a simple scheduler lib, handling tasks and executes them at r
 ## Examples
 * Init a new scheduler with 4 workers
 ```go
+package main
+
 import (
 	"context"
+	"time"
 
 	scheduler "gitea.thegux.fr/rmanach/cycle-scheduler.git"
 )
 
-ctx := context.Background()
-s := scheduler.NewSchedulerCycle(ctx, 4)
+func main() {
+	ctx, fnCancel := context.WithCancel(context.Background())
+	s := scheduler.NewSchedulerCycle(ctx, 4)
 
-// add a task with an execution interval of 2 ms (executed every 2 ms)
-// and a maximum duration of 30 second.
-taskID := s.Delay(
-	func(ctx context.Context) (any, error) {
-		// ...
-		return any, nil
-	}, 
-	scheduler.WithExecInterval(2*time.Millisecond),
-	scheduler.WithMaxDuration(30*time.Second)
-)
+	// add a task with an execution interval of 2 ms (executed every 2 ms)
+	// and a maximum duration of 30 second.
+	s.Delay(
+		func(ctx context.Context) (any, error) {
+			// ...
+			return nil, nil
+		},
+		scheduler.WithExecInterval(2*time.Millisecond),
+		scheduler.WithMaxDuration(30*time.Second),
+	)
 
-<-ctx.Done()
-<-s.Done()
+	// stop the program after 5 seconds
+	go func() {
+		time.Sleep(5 * time.Second)
+		fnCancel()
+	}()
+
+	<-ctx.Done()
+	<-s.Done()
+}
 ```
 
 **NOTE**: for `Delay` optionals arguments, check the `NewTask` method documentation for more details.