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

Terry Li
Terry Li
2,548 Points
Posted by Terry Li
Terry Li
2,548 Points

Optional vs default values?

Why for some of stored properties we set them as optional while for the rest we set default values? Thanks!

1 Answer

Michael Kannard
Michael Kannard
2,555 Points
Michael Kannard
Michael Kannard
2,555 Points

This is a design decision. He has set the UIColor to transparent by default, because he considers that to be the uninitialized color value. He's setting it up so, if you don't set the color, you get a transparent background. It's all about intent of use. The same goes for the artist array. If you don't setup any artist, you get an empty array, not an array set to nil. This is easier for the user of your struct.