callback = $callback; } /** * Determine if the validation rule passes. * * @param string $attribute * @param mixed $value * @return bool */ public function passes($attribute, $value) { $this->failed = false; $this->callback->__invoke($attribute, $value, function ($message) { $this->failed = true; $this->message = $message; }); return ! $this->failed; } /** * Get the validation error message. * * @return string */ public function message() { return $this->message; } }