Use playlist !.[property] instead of playlist?.[property]

! ? are both used in Swift as optionals. Most of the time when you make a API call i.e. get some data from the internet you are taking that data and unwrapping it into a data type.

So for example you get some data back about the weather in a city and you want to display the city name:

{ City : "London" }

We could take this data and create the following variable and pass the value into it:

var city:String! = "London";

-> Here we have a variable which is expecting to be a String, the use of ! in simple terms say the value of this variable will explicitly be a String. However the catch is that in some instance if you didn't get a String this due to a data error and instead you got nothing back, it would stop working because it is expecting a String as this data type. So to fix this and prevent a programme melt down you could do:

var city:String? = "London"

-> The ? is saying I may get a String but if it is nil we can still run the programme.

var Latitude: double? = 55.34;

-> Here we could get a double but hey of I get nothing back we can still run the programme.

Working with Swift what you will find is that we tend to use ? and ! a lot to check so worth spending some time on it.