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Karan Keelor
Karan Keelor
3,005 Points

Binary operator += cannot be applied to types '[String]' and 'String'???

struct Playlist {

    var title: String?
    var description: String?
    var icon: UIImage?
    var largeIcon: UIImage?
    var artists: [String] = []
    var backgroundColor: UIColor = UIColor.clearColor()

    init (index:Int) {                               // Whats going on here
        let musicLibrary = MusicLibrary().library   // import the entire array to this constant
        let playlistDictionary = musicLibrary[index]  //selecting the dictionary that is in the array

        title = playlistDictionary["title"] as! String!
        description = playlistDictionary["description"] as! String!

        let iconName = playlistDictionary["icon"] as! String!
        icon  = UIImage(named: iconName)

        let largeIconName = playlistDictionary["largeIcon"] as! String!
        largeIcon = UIImage(named: largeIconName)

        artists += playlistDictionary["artists"] as! String!  
//this is where I'm getting the error.
//Binary operator += cannot be applied to types '[String]' and 'String'???


1 Answer

Michael Bates
Michael Bates
13,344 Points

Hi there Karan! It looks like your issue is the lack of brackets that is needed to surround 'String' as such:

        artists += playlistDictionary["artists"] as! [String]

This will allow you to declare the binary operator in relation to the 'artists variable' that is declared at the beginning when you assigned the 'artist variable' as such:

var artists: [String] = []

Hope that helps!