Zend Framework 2 EventManager

Code
<?php

use Zend\EventManager\EventManager;
use 
Zend\EventManager\Event;

$eventListener1 = function (Event $event) {
    echo 
'Call me' PHP_EOL;
};

$eventListener2 = function (Event $event) {
    echo 
'Call me too' PHP_EOL;
};

$eventListener3 = function (Event $event) {
    echo 
'Call me three' PHP_EOL;
};

$eventManager = new EventManager();
$eventManager->attach('callme'$eventListener1);
$eventManager->attach('callmetoo'$eventListener2);
$eventManager->attach('callme'$eventListener3);

$eventManager->trigger('callme');
Result
Call me
Call me three
Used Versions
PHP 7.1, Zend 3.0, Symfony 3.2, Laravel 5.2, PHPUnit 5.6, Doctrine 2.6