addHelperFunction('format', function () {
    return Format::getInstance();
});
$this->addHelperFunction('timeSince', function ($timestamp) {
    return ''
        . Format::timeSince($timestamp)
        . '';
});
$this->addHelperFunction('prefixedTimeSince', function ($timestamp, $ucfirst = false) {
    return ''
        . Format::prefixedTimeSince($timestamp, $ucfirst)
        . '';
});
$this->addHelperFunction('timeUntil', function ($timestamp) {
    if (! $timestamp) return '';
    return ''
        . Format::timeUntil($timestamp)
        . '';
});
$this->addHelperFunction('prefixedTimeUntil', function ($timestamp, $ucfirst = false) {
    if (! $timestamp) return '';
    return ''
        . Format::prefixedTimeUntil($timestamp, $ucfirst)
        . '';
});