You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: future_example_test.go
    path of file: ./repos/protoactor-go/actor
    
    the code of the file until where you have to start completion: package actor_test

import (
	"fmt"
	"sync"
	"time"

	"github.com/asynkron/protoactor-go/actor"
)

var system = actor.NewActorSystem()

func ExampleFuture_PipeTo() {
	var wg sync.WaitGroup
	wg.Add(1)

	// test actor that will be the target of the future PipeTo
	pid := system.Root.Spawn(actor.PropsFromFunc(func(ctx actor.Context) {
		// check if the message is a string and there
    
func ExampleFuture_PipeTo() {
	var wg sync.WaitGroup
	wg.Add(1)

	// test actor that will be the target of the future PipeTo
	pid := system.Root.Spawn(actor.PropsFromFunc(func(ctx actor.Context) {
		// check if the message is a string and therefore
		// the "hello world" message piped from the future
		if m, ok := ctx.Message().(string); ok {
			fmt.Println(m)
			wg.Done()
		}
	}))

	f := actor.NewFuture(system, 50*time.Millisecond)
	f.PipeTo(pid)
	// resolve the future and pipe to waiting actor
	system.Root.Send(f.PID(), "hello world")
	wg.Wait()

	// Output: hello world
}