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iOS

Posted by Sean Krause
Sean Krause
2,155 Points

Using a key from a class call dictionary value in a control flow statement.

Hello all!

Let me start by saying i am a beginner, i have been coding for about 2 months now and am completely new to swift.

Sorry about the wordy title but i couldnt figure out any other way to word it haha, maybe you can help me on that too!

I have been trying to do this for a couple days and cant seem to find an answer. I have exhausted all the tools in my toolbox on this one. I need to take the title from the book call in the catalogue dictionary and add it into a control flow statement so if someone checks out a book, it will show checkedOutBooks dictionary that it is either checked out or available. I have attempted to do this in a for loop but i cant figure out how to pull out just the title from the catalogue dictionary.

I get this error, not sure why.

--> Expression pattern of type 'String' cannot match values of type 'Book' <--

All the code also wont go in the code snippet for some reason.

Please let me know if i could help you help me.

class Book {  
    var title: String!
    var author: String!

    init(_ bookTitle:String, _ bookAuthor:String) {
        title = bookTitle
        author = bookAuthor
    }  
}
class Library 
{
    var catalogue = ["ORW":Book("1985", "George Orwell"),
                     "RAY":Book("Fahrenheit 451", "Ray Bradbury")]

    var checkedOutBooks = [String:Person]()

    func searchByTitle(_ title:String) -> String {

        // TODO: This function searches the catalogue dictionary for a title
        //
        // Returns "Available" if the book exists and isn't checked out
        //
        // Returns "Checked out by name" if the book exists and is checked out
        //
        // Returns "Not in catalogue" if the book doesn't exist

        for (_, value) in catalogue {
            switch value {
            case "1985": return"Available"
            case "Fahrenheit 451": return"Available"
            default: return("Not in catalogue")
            }
        }