$_cycles = array();
function cycle() {
        global $_cycles;
        $args = func_get_args();
        $last_arg = count($args) - 1;
        $name = 'default';
        if (is_array($args[$last_arg])) {
                $name = $args[$last_arg]['name'];
                unset($args[$last_arg]);
        }
        @$_cycles[$name] = (null === $_cycles[$name] || $_cycles[$name] + 1 >= count($args)) ? 0 : $_cycles[$name] + 1;
        return $args[$_cycles[$name]];
}
       
function reset_cycle($name = 'default') {
        global $_cycles;
        @$_cycles[$name] = null;
}

echo cycle('foo', 'bar', 'baz', array('name' => 'vars'));
echo cycle('4', '8', '15', '16', '23', '42', array('name' => 'numbers'));
echo cycle('row', 'row_alt');
reset_cycle('numbers');