A builder pattern in swift which follow Head First Design Pattern

ContactBuilder.swift

class Contact {
    private(set) lazy var name: String
    private(set) lazy var phoneNumber: String
    private(set) lazy var address: String
    private(set) lazy var gender: String
    
    private init(
        name: String,
        phoneNumber: String,
        address: String,
        gender: String
    ) {
        self.name = name
        self.phoneNumber = phoneNumber
        self.address = address
        self.gender = gender
    }
    
    class Builder {
        private(set) lazy var name: String = ""
        private(set) lazy var phoneNumber: String = ""
        private(set) lazy var address: String = ""
        private(set) lazy var gender: String = ""
        
        func setName(name: String) -> Builder {
            self.name = name
            return self
        }
        
        func setPhoneNumber(phoneNumber: String) -> Builder {
            self.phoneNumber = phoneNumber
            return self
        }
        
        func setAddress(address: String) -> Builder {
            self.address = address
            return self
        }
        
        func setGender(gender: String) -> Builder {
            self.gender = gender
            return self
        }
        
        func build() -> Contact {
            return Contact(
                name: name,
                phoneNumber: phoneNumber,
                address: address,
                gender: gender
            )
        }
    }
}

let c = Contact.Builder()
    .setName(name: "raditya")
    .setAddress(address: "jakarta")
    .setPhoneNumber(phoneNumber : "+62")
    .setGender(gender : "male")
    .build()

print(c.name)
print(c.address)
print(c.phoneNumber)
print(c.gender)