更新到Swift3.0后有些差异是需要我们重新了解的。

Swift 3改变可以分为两个大的部分

1. 移除在Swift 2.2中弃用的方法
2. 语言更加安全，优雅

1、Range
Range在Swift3.0的初始化方式有所不同

var range:Range<Int> = Range(uncheckedBounds: (0,5))
//结果通[0..<5]一致

Range初始化方法需要我们传入一个元祖，一个最小值和一个最大值

public init(uncheckedBounds bounds: (lower: Bound,upper: Bound))

2、ClosedRange

var range:ClosedRange<Int> = ClosedRange(uncheckedBounds: (0,5))
//结果通[0...5]一致

3、replaceSubrange

//闭区间
//method1
var array2 = [2,1,2]
array2.replaceSubrange(ClosedRange(uncheckedBounds:(0,1)),with: [1])

//method2
array2.replaceSubrange(CountableClosedRange(uncheckedBounds:(0,with: [1])


//开区间
//method3
array2.replaceSubrange(Range(uncheckedBounds:(0,2)),with: [1])

//method4
array2.replaceSubrange(CountableRange(uncheckedBounds:(0,with: [1])

通过对比了解到method1和method2结果一致，method3和method4结果一致。

4、inout

//数据交换
func swap( a:inout Int,b:inout Int){
    let c = a
    a = b
    b = c
}

var x = 2,y = 3
swap(&x,&y)

5、indices

//创建所有能够用来访问字符串中独立字符的索引范围 Range
for index in greeting.characters.indices{
     print("\(greeting[index]) ",terminator: "")
}

6 、do while 改为 repeat while

repeat {
    statements
} while condition