## STRUCTS
Structs（结构体） 是一种复杂数据类型，包含了多个值，通过 struct 关键字定义一个结构体：
~~~
struct Person {
var clothes: String
var shoes: String
}
~~~
Swift 让你非常简单地创建一个结构体变量，只需要将初始值传入即可：
~~~
let taylor = Person(clothes: "T-shirt", shoes: "sneakers")
let other = Person(clothes: "short skirts, shoes: "high heels")
~~~
通过结构体变量名以及属性名来访问属性的值：
~~~
print(taylor.clothes)
print(other.shoes)
~~~
Swift 有一个名为"copy on write"的机制，当你将一个结构体变量赋给另一个变量时，会独立拷贝一份：
~~~
struct Person {
var clothes: String
var shoes: String
}
let taylor = Person(clothes: "T-shirts", shoes: "sneakers")
let other = Person(clothes: "short skirts", shoes: "high heels")
var taylorCopy = taylor
taylorCopy.shoes = "flip flops"
taylor //(clothes: "short skirts", shoes: "high heels")
taylorCopy //(clothes: "short skirts", shoes: "flip flops")
~~~
