:)

<?php
final class Present
{
    protected $_is;
    static protected $_now;
    static protected $_time;

    public function __construct()
    {
        self::$_now = $this;
        return $this;
    }

    protected function _is()
    {
        return $this->_is;
    }

    public function getInstant()
    {
        if ($this->_is) {
            $this->_is = false;
            return time();
        }
        $this->_is = true;
        $date = self::$_now->getInstant();
        return $date;
    }
}

$time = new Present();
echo $time->getInstant();