MathPHP\Functions\Arithmetic::add PHP Метод

    public static function add(callable ...$args)
    {
        $sum = function ($x, ...$args) {
            $function = 0;
            foreach ($args as $arg) {
                $function += $arg($x);
            }
            return $function;
        };
        return function ($x) use($args, $sum) {
            return call_user_func_array($sum, array_merge([$x], $args));
        };
    }