protected function getInputType($input)
    {
        // Get the formal type
        $type = gettype($input);

        // Check if it's numeric
        if ($type == 'integer' || $type == 'float' || $type == 'double')
            $type = 'numeric';

        // If it's something we don't check, null it
        if ($type == 'NULL' || $type == 'object' || $type == 'resource' || $type == 'undefined type')
            $type = null;

        // Check if it's an file array
        if ($type == 'array' && isset($input['type']) && $input['tmp_name'])
            $type = 'file';

        return $type;
    }