Closures in Swift

//

Main.swift

//  Closed Package

//

//Created by Zhu Min On 15/6/15.

//Copyright (c) years Helinyu. All rights reserved.

//

Import Foundation

Let names = ["Lily","Anna","Duty","Poly" ,"Gray"]

func comparename (S1:string , s2:string) Bool {return s1 < s2}

var sortedarray = names.sorted (comparename)

//println (" changes after permutation:\ (sortedarray)");

var Sortedarray = names.sorted ({(S1:string, s2:string),Bool In return s1 < s2})

println (" changes after permutation:\(sortedarray)" );

Let A = 5

Let A = 4

println (a)

// The following function implements the addition of two string variables

func SayHello (S1:string , s2:string) {

var str = s1 +"" + s2

println ("The values is:\(str)")

}

SayHello ("Nihao","Helinyu")

/*

1:func is a function keyword

2:say is the function name, which represents the address of the function

3:say function parameter is an integer return value of Boolean type

*/

func Say (num:Int) Bool {

return num >ten

}

var by : ( Int ),Bool = Say

/*

1 : Say is the address of the function name, and the function type, parameter is shaping, return value Boolean type

2 : ( Int)->bool represents the function type, the parameter is shaped , and the return value is a Boolean type.

namely: by is a function variable (the parameter is shaped and the return value is a Boolean type) point to function name (Say)

*/

var B = by (ten) //by (a) calling functions directly

println (b)

/*

function Getlist Description

Parameters:

1 : The first parameter Shaping set variables

2 : Second argument, function type variable parameter is an integer return value Boolean type

return value

Shaping a Collection

*/

Func GetList (arr:int[], pre: (Int)->bool)->int[]{

//    // defines an empty variable-shaping collection

var Temparr = int[] ()

//

For temp in arr {

If pre (temp) {

Temparr + = temp;

//        }

//    }

return Temparr;

//}

//

///*

// called Getlist Description

// first parameter Shaping an array [1,2,3,4]

// a second parameter The closure to point to the function type.

//{(s) in return s>2} closure type description, parameter is shaping , The return value is a Boolean type

//*/

Let Arr=getlist ([1,2,3,4],{(S:int) in return s>2})

println (arr)

// in class " Instance Properties " when there is no initialization, the compilation is not over.

// Solution: 1) Initialize when defining variables 2 Initialized using the initialization method

class Rect

{

var width:int = 0;

var height:int = 0;

// or

var width:int;

var height:int;

//

//    // Initialize Method

Init ()

//    {

width = 0;

Height = 0;

//    }

//3) or

var width:Int;

var height:Int;

init(w:int, h:int)

{

width = w;

Height = h;

}

func setSize (w:int, height:int)

{

width = w;

self. height = height;

}

Func Getarea ()-int{

return self.width * height;

//    }

}

var rect = rect ();

Rect.setsize (ten, height:20);

var rect = rect (w:ten, H:)

println ("The area obtained is:\(rect)")

println ("The area obtained is:\(rect)")

Copyright NOTICE: This article for Bo Master original article, without Bo Master permission not reproduced.

Closures in Swift