swift5.0 -- 函数

func test()
{
    print("222")
}

test()

func test1() -> Int{
    return 100
}
print(test1())

func test2(name: String) -> String{
    return name
}

print(test2(name: "hello world"))

func test3(name:String...){
//    print(type(of: name))
    for item in name {
        print(item)
    }
}

test3(name: "a","b")

func test5(name:(n1:String,n2:Int)) -> (String,Int){
    var value:(a:String, b:Int)
    value.a = name.n1 + " hello"
    value.b = name.n2 + 100
    
    return value
}

var value = test5(name: (n1:"world",n2:20))
print(value)

func test1() -> Void
{
    print("test1()")
}

var a:() -> Void = test1

a()

//匿名函数
var b:() -> Void = {() -> Void in
    print("匿名函数")
}
b()

print("---------------------")

func test2(param:String, param1:Int) -> String
{
    return param + String(param1)
}

var c:(String, Int) -> String = test2

let dc = c("hello", 10)
print(dc)

var d:(String, Int) -> String = {(param1: String, param2: Int) -> String in
    return param1 + String(param2)
}

let dd = d("王敏",22)
print(dd)

print("---------------------")

func test3(param:[Int]) -> String
{
    var temp: String = ""
    
    for item in param {
        temp = temp + String(item)
    }
    return temp
}

var e:([Int]) -> String = test3

var value = e([1,2,3])
print(value)

var f:([Int]) -> String = {(a:[Int]) -> String in
    
    var temp: String = "--"
    
    for item in a {
        
        temp = temp + String(item)
    }
    return temp
}

//print(f([4,5,6]))

var g:([Int]) -> String = e
print(g([10,11,12]))

func test()
{
    print("test()函数，没有参数，没有返回值")
}

var a:() -> Void = test
//a()

func test1(param:()->Void)
{
    param()
}

//test1(param: test)

test1(param: {() -> Void in
    print("test()函数，没有参数，没有返回值")
})
print("-------------------")

func sum(param:(Int,Int) -> Int) -> Int
{
    var value = param(1,2)
    print("value=\(value)")
    return value
}
func add(a:Int, b: Int) -> Int
{
    return a + b
}
//sum(param: add)

var value1 = sum(param: {(a, b) -> Int in
    return a + b
})

print("323:\(value1)")

var array = [1,3,5,0,2,8]

func paly2(a:Int, b:Int) -> Bool
{
    if a < b {
        return true
    }else{
        return false
    }
}
//array.sort(by: {(a, b) -> Bool in
//    if a < b {
//        return true
//    }else{
//        return false
//    }
//})
array.sort(by: paly2)
print(array)


func paly1(value:Int) -> Int
{
    return value * value
}

func play2(value: Int) -> Int
{
    return value + value
}

func test(param:Bool) -> (Int) -> Int
{
    return param ? paly1 : play2
}

var a = test(param: true)

print(a(3))

print("-----------------------")

func test1(param:Bool) -> (Int) -> Int
{
    func play1(value:Int) -> Int
    {
        return value * value
    }
    func paly2(value: Int) -> Int
    {
        return value + value
    }
    
    return param ? play1 : paly2
}
var b = test1(param: true)

print(b(4))

var a:() -> Void = {() -> Void in
    print("a")
}

print(type(of: a))

var b:() -> Void = {
    print("b")
}

b()

print("====================")

//不带参数，不带返回值
func test(parm:() -> Void)
{
    parm()
}
test(parm: {print("不带参数不带返回值")})

print("====================")

func test2(param:(Int) -> Void)
{
    param(10)
}
test2(param: {(value: Int) -> Void in
    print(value)
})

test2(param: {(value) in
    print(value)
})

print("--------------")

func test3(param: (Int, Int) -> Int)
{
    print(param(10,20))
}

//test3(param: {(item1: Int, item2: Int) -> Int in
//    return item1 + item2
//})

test3(param: {$0 + $1})