swift5.0 尾随闭包

func play1(param1:String,param2:(String) ->Void)
{
    param2(param1 + "---swift")
}

//play1(param1: "hello", param2: {(data:String) -> Void in
//    print(data)
//})

play1(param1: "world") { (data) in
    print(data)
}

func play2(param:(String) -> String)
{
    var value = param("swift")
    
    print("返回值:\(value)")
    
}

//play2(param: {(data) -> String in
//
//    return data + "--ios"
//})
play2 { (data) -> String in
    return data+"---ios1"
}

func play3(parm:() -> Void)
{
    parm()
}

play3(parm:{
    print("play3")
})

play3(){
    print("play3")
}

play3 {
    print("play3")
}

func play4(param:() -> String)
{
    var value = param()
    print("value =\(value)")
}

play4(param: {()->String in
    return " hello"
})

play4(){() -> String in
    return "hello world"
}

play4 { () -> String in
    return " play4 ---"
}

play4{
    return " dsds"
}

func play5(param1:(Int) -> Void, param2:Int)
{
    param1(param2 * 2)
}

play5(param1: {(data:Int) -> Void in
    print(data)
}, param2: 100)

play5(param1: {(data) in
    print(data)
}, param2: 100)