public function validate() {
        // Deny if rules array is empty
        if (empty($this->rules))
            return true;
        // If rules are invalid
        if (!is_array($this->rules))
            throw new \Exception("The rules must be an array of the validator|sanitize rules", 1);
        // Loop the rules
        foreach ($this->rules as $rule) {
            // Run rule
            $rule instanceof \Closure
                ? $rule($this)
                : call_user_func($rule, $this);
        }
        // Check the field is valid
        return !$this->hasError();
    }