Structify

struct User {
    let address: String
    let company: String
    let email: String
    let name: String
    let phone: String
    let uid: String
    let username: String
    let website: String
    let birthday: Date
}

class RLMUser: Object {

    @objc dynamic var address: String = ""
    @objc dynamic var company: String = ""
    @objc dynamic var email: String = ""
    @objc dynamic var name: String = ""
    @objc dynamic var phone: String = ""
    @objc dynamic var uid: String = ""
    @objc dynamic var username: String = ""
    @objc dynamic var website: String = ""
    @objc dynamic var birthday: Date = Date()
    
    override class func primaryKey() -> String? {
        return "uid"
    }
}

extension RLMUser {
    func toStruct() -> User {
        return User(address: address,
                    company: company,
                    email: email,
                    name: name,
                    phone: phone,
                    uid: uid,
                    username: username,
                    website: website,
                    birthday: birthday)
    }
}

extension User {
    func toObject() -> RLMUser {
        return RLMUser.build { object in
            object.uid = uid
            object.address = address
            object.company = company
            object.email = email
            object.name = name
            object.phone = phone
            object.username = username
            object.website = website
            object.birthday = birthday
        }
    }
}

struct User {
    var address: String = ""
    var company: String = ""
    var email: String = ""
    var name: String = ""
    var phone: String = ""
    var uid: String = ""
    var username: String = ""
    var website: String = ""
    var birthday: Date = Date()
}

class RLMUser: Object {
    //you only set the primaryKey as usual 
    override class func primaryKey() -> String? {
        return "uid"
    }
}

extension RLMUser: StructConvertible {
    typealias StructType = User
}

extension User: ObjectConvertible {
    typealias ClassType = RLMUser
}