复制
1const person = {
2	firstName: "Lydia",
3	lastName: "Hallie",
4	pet: {
5		name: "Mara",
6		breed: "Dutch Tulip Hound"
7	},
8	getFullName() {
9		return `${this.firstName} ${this.lastName}`;
10	}
11};
12
13console.log(person.pet?.name);
14console.log(person.pet?.family?.name);
15console.log(person.getFullName?.());
16console.log(person.getLastName?.());