Swift 4.0 废弃的柯里化

// 柯里化

// http://www.jianshu.com/p/6eaacadafa1a                               Swift 2.0 柯里化方法 (废弃)

// http://www.swifthumb.com/thread-16079-1-1.html                      Swift 3.0 柯里化常用方法推荐

// http://www.ruanyifeng.com/blog/2012/04/functional_programming.html  函数式编程

/*

Curried function declaration syntax func foo(x: Int)(y: Int) is of limited usefulness and creates a lot of language and implementation complexity. We should remove it.

(函数的 currying 特性的使用场景并不大，但他会增加很多语言的复杂性，所以需要删除它)

*/

 class Currying

 {

     // uncurried:普通函数

     // 接收多个参数的函数（与类相关的函数，统称为方法，但是这里就直接说函数了，方便理解）

     func add(a: Int, b: Int, c: Int) -> Int{

         print("\(a) + \(b) + \(c)")

         return a + b + c

     }

     // curried:柯里化函数 --> 本质函数式编程思想

     func addCur(_ a: Int) -> (Int) -> (Int) -> Int{

         return {

             b in

             return {

                 c in

                     a + b + c

             }

         }

     }

 }

 let curry = Currying()

 var number = Currying.addCur(curry)()()()

 print(number)

 // NO.2

 let datePrint:(Int)->(Int)->(String)->Void =

 {

     month in

     print("\(month)月")

     return{

         day in

         print("\(day)日")

         return{

             action in

             print("\(action)")

         }

     }

 }

 let actionPrint = datePrint()()

 actionPrint("写详细")