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

Posted by Michael Psoinos
Michael Psoinos
8,178 Points

How can the dictionaries in the library array have different value types?

"library" is an array of dictionaries. The first 4 key-value pairs in each dictionary (for title, description, icon, and largeIcon) are of type [String: String]. But the key-value pairs for backgroundColor and artists are [String: [String: Int]] and [String: [String]].

Apple says that dictionaries are unordered lists of the same type, such as [String: String]. What is the dictionary type for a library array element? They have different types. Why doesn't Xcode give an error?