main.php

<?php
/**
 * This file is part of the php4fun package.
 *
 * (c) Aleh Kashnikau <[email protected]>
 *
 * Created: 22/07/2014 3:31 PM
 */

class YieldTest{
    public static $flag = true;
    public static function generate(){
        $i=0;
        while(self::$flag){
            yield $i++;
        }
    }
}
$generator = YieldTest::generate();
foreach($generator AS $value){
    var_dump($value);
    if($value > 5)
        YieldTest::$flag = false;
}