public function renameMany(array $map) : Assoc
    {
        $pairs = array_map(function ($a, $b) {
            return [$a, $b];
        }, array_keys($map), array_values($map));

        return array_reduce($pairs, function ($that, $pair) {
            list ($from, $to) = $pair;

            return $that->rename($from, $to);
        }, $this);
    }