Swift访问多嵌套结构中的结构

struct Person {
    var name: String
    var age: Int
}

struct Address {
    var street: String
    var city: String
}

struct Contact {
    var person: Person
    var address: Address
}

let john = Person(name: "John", age: 30)
let address = Address(street: "123 Main St", city: "New York")
let contact = Contact(person: john, address: address)

// 访问多嵌套结构中的结构
let contactName = contact.person.name
let contactAge = contact.person.age
let contactStreet = contact.address.street
let contactCity = contact.address.city

print(contactName) // 输出: John
print(contactAge) // 输出: 30
print(contactStreet) // 输出: 123 Main St
print(contactCity) // 输出: New York