use React\EventLoop\Factory as Loop;
use React\Async;
use React\Promise\Deferred;
$loop = Loop::create();
$deferred = new Deferred;
$promise = $deferred->promise();
$loop->addTimer(0.02, function() use($deferred) {
 $deferred->resolve();
});
$foo = function() use($promise) {
 Async\await($promise);
 echo 'All good' . PHP_EOL; 
};
$loop->addTimer(0.01, $foo);
$loop->run();