PEAR_Downloader::_sortInstall PHP Метод

    function _sortInstall($a, $b)
    {
        if (!$a->getDeps() && !$b->getDeps()) {
            return 0;
            // neither package has dependencies, order is insignificant
        }
        if ($a->getDeps() && !$b->getDeps()) {
            return 1;
            // $a must be installed after $b because $a has dependencies
        }
        if (!$a->getDeps() && $b->getDeps()) {
            return -1;
            // $b must be installed after $a because $b has dependencies
        }
        // both packages have dependencies
        if ($this->_dependsOn($a, $b)) {
            return 1;
        }
        if ($this->_dependsOn($b, $a)) {
            return -1;
        }
        return 0;
    }