Use of undeclared type 'Object'

if you are using Realm then import

import RealmSwift

Complete syntax of class.

import UIKit
import RealmSwift

class User: Object {

}

If you face any difficulty to implement this code. Watch below video Link: https://youtu.be/5Z8tBKwk6-c

Just remove : Object. Pure Swift classes don't need to inherit from a superclass

Pure Swift object doesn't inherit from a superclass:

class Person {}

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