[== PHP ==]
        /**
         * sort an array
         *
         * @access public
         * @param  array   $array          - array to sort
         * @param  mixed   $index          - key to sort by
         * @param  string  $order          - 'asc' (default) || 'desc'
         * @param  boolean $natsort        - default: false
         * @param  boolean $case_sensitive - sort case sensitive; default: false
         *
         **/
        function sort($array, $index, $order='asc', $natsort=false, $case_sensitive=false)
        {
            if (is_array($array) && count($array)) {
                foreach (array_keys($array) as $key) {
                    $temp[$key] = $array[$key][$index];
                }
                if (!$natsort) {
                    ($order=='asc') ? asort($temp) : arsort($temp);
                } else {
                    ($case_sensitive) ? natsort($temp) : natcasesort($temp);
                    if ($order != 'asc') {
                        $temp = array_reverse($temp, true);
                    }
                }
                foreach (array_keys($temp) as $key) {
                    (is_numeric($key)) ? $sorted[]=$array[$key] : $sorted[$key]=$array[$key];
                }
                return $sorted;
            }
            return $array;
        }   // end function sort()

...

        $sorted_tags = sort($tags, 'tag', 'asc', true);