public static function processValue($value, $allowServices = false)
    {
        if (\is_array($value)) {
            foreach ($value as $k => $v) {
                $value[$k] = static::processValue($v, $allowServices);
            }

            return $value;
        }

        if ($value instanceof ReferenceConfigurator) {
            return new Reference($value->id, $value->invalidBehavior);
        }

        if ($value instanceof InlineServiceConfigurator) {
            $def = $value->definition;
            $value->definition = null;

            return $def;
        }

        if ($value instanceof self) {
            throw new InvalidArgumentException(sprintf('"%s()" can be used only at the root of service configuration files.', $value::FACTORY));
        }

        switch (true) {
            case null === $value:
            case is_scalar($value):
                return $value;

            case $value instanceof ArgumentInterface:
            case $value instanceof Definition:
            case $value instanceof Expression:
            case $value instanceof Parameter:
            case $value instanceof Reference:
                if ($allowServices) {
                    return $value;
                }
        }

        throw new InvalidArgumentException(sprintf('Cannot use values of type "%s" in service configuration files.', \is_object($value) ? \get_class($value) : \gettype($value)));
    }