Relationship method must return an object of type
请大神支招: 问题:在laravel 5.2.45下使用本视频中_form.blade.php页面性别处理 {{ isset($student->sex) && $student->sex == $ind ? 'checked' : '' }},会报LogicException in Model.php line 2723: Relationship method must return an object of type Illuminate\Database\Eloquent\Relations\Relation错误。 菜鸟一枚,请多指教。不胜感谢!(视频laravel版本5.2.22)