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iOS Build a Playlist Browser with Swift Building the Music Library and Playlist Models Passing the Playlist Object

Joseph Kandi
Joseph Kandi
2,640 Points
Posted by Joseph Kandi
Joseph Kandi
2,640 Points

Why are we not checking the value of the title since its been declared as an optional String

We are checking for the optional playlist stored property but we did also declare the title of the playlist to have an optional title, why are we not checking for a nil value in the title of the playlist?

3 Answers

Marie Nipper
Marie Nipper
22,638 Points
Marie Nipper
Marie Nipper
22,638 Points

A few videos back he explains why he set it as an optional value. It would be good to check to see if it is an optional if it was data from the web that could return nil. However, it shouldn't return nil as the data is hard coded in the MusicLibrary struct. So that's my guess as to why he's not worried about checking for a nil value.

kjvswift93
kjvswift93
13,515 Points
kjvswift93
kjvswift93
13,515 Points

Could you maybe rephrase your question? I don't quite understand what you are asking.

Joseph Kandi
Joseph Kandi
2,640 Points
Joseph Kandi
Joseph Kandi
2,640 Points

On the video "Passing the Playlist Object", Parsan creates an optional playlist stored property, and later on he checks for a nil value but does not also check for nil on the playlist title property, my question is , why is that? Why check only for the playlist property and also not for its title since its been declared as an optional string in the struct?

Rafael Schwemmer
Rafael Schwemmer
6,109 Points
Rafael Schwemmer
Rafael Schwemmer
6,109 Points

I think it is because we are already unwrapping the title in the init method of the Playlist struct:

title = playListDictionary["title"] as! String!

So when we create an instance of the Playlist struct, the title is automatically unwrapped.